ss / te NORMANDIE starting
from cold
BUILDERS: PENHÖET, St. Nazaire, France
This document is
almost exclusively about the engineering aspects of NORMANDIE, mainly on
how to start her up from cold. If you are looking for photos of the passenger
spaces, there is a plethora of them on the web, in Facebook groups - Admirers of the ss Normandie, ss Normandie photographic file, The French Ocean Liners / Les Paquebots Français, ss Normandie, GREAT LINERS OF THE PAST & PRESENT, and others, Pinterest
and in articles about NORMANDIE here in the blog, please see at the end of the article.
Using "ss" for NORMANDIE is quite incorrect, as NORMANDIE was a Turbo Electric vessel and not a steamship, therefore NORMANDIE should be adressed as "te".
by Earl of Cruise
te / ss NORMANDIE berthed in Le Havre, Gare Maritime May 29th, 1935 - colouring courtesy Daryl LeBlanc
NORMANDIE was, from her inauguration till the end, "the Peak of
Chic".
It was a "must do" for international high society to make a crossing on "Le Vaisseau de Lumière", the Ship of Light, in order to make their mark in Society. During the inaugural crossing of NORMANDIE, "la Deesse de la Mer" was the headquarter of Parisien society ... On board NORMANDIE in the so-called "flirty thirties" could be seen the cream of mid 30s society, and NORMANDIE was the perfect stage on which to be presented and to be seen; even the arrangement and number of staircases on board gave each passenger the possibility for their own grand entrance. NORMANDIE was designed down to the last detail, with every part of that phenomenal vessel built to endure: The hull of the NORMANDIE was designed by Vladimir Yourkevitch, the brilliant Russian emigre. The design was so advanced, that NORMANDIE was able to snatch the Blue Riband with her 160,000hp and maximum speeds over 30 kts, with an average speed of nearly 30 kts. The exterior gave the lines for the future to come, as well as the interior with the lay out concept in the public rooms, cabins and suites. As a first on any Transatlantic liner, NORMANDIE offered a huge number of veranda suites on the promenade deck, where the well-heeled passengers could open their windows to enjoy the bracing Atlantic sea air.
Despite her disastrous ending by fire, NORMANDIE had the
most advanced fire fighting system installed, still innovative today, and if only the incompetent organisation of the refit company had not shut down the vessel systems completely - especially this fire prevention and extinguishing system - the outcome would no doubt have been different.
The vast fire doors on the promenade deck could have withstood the original fire caused by a careless worker; in fact the closed theater was unharmed in the event, to the surprise of the officials. The enthusiasm of the fire brigade sealed her fate by capsize in much the same way as the Empress of Canada in Gladstone Dock, Liverpool.
The dining room was at least the first large air conditioned room on the Atlantic and bigger than the Hall of Mirrors at Versailles. No room since NORMANDIE on any ship was ever that grand and spacious. No restaurant afloat ever offered such such fine food in the best traditions of French Cuisine.
te / ss NORMANDIE, Grand Salle á Manger 1ère Classe - colouring courtesy Daryl LeBlanc
NORMANDIE was the benchmark of luxury in the 30s and
thereafter, as no vessel was ever designed that grand again.
NORMANDIE had a long list of firsts offered on board on the North Atlantic, such as a full blown theatre and cinema, the above mentioned veranda suites, a permanent outdoor pool as well an indoor pool, the air conditioned dining room, and for all classes the egalitarian view of the wake of the ship when underway - no class restrictions there ... After having a tour on board NORMANDIE which included the machinery rooms, Fred Astaire was so impressed that he recreated it as a film set in the film "SHALL WE DANCE". He was so impressed that his machine room film set was made all in white, as were all the machinery rooms of NORMANDIE - spotlessly clean. 
te / ss NORMANDIE, dance scene inspired by NORMANDIE´s clean machine room Slap That Bass, SHALL WE DANCE
te / ss NORMANDIE, dance scene inspired by NORMANDIE´s clean machine room SHALL WE DANCE
te / ss NORMANDIE, dance scene inspired by NORMANDIE´s clean machine room SHALL WE DANCE
Not only for the aficionados, NORMANDIE was and is the
perfect ocean liner which has never been equaled. Alongside NORMANDIE, other vessels tended to look old-fashioned and only to be pitied as they tried to emulate the impossible!
te / ss NORMANDIE, dance scene inspired by NORMANDIE´s clean machine room Slap That Bass, SHALL WE DANCE
by Earl of Cruise
|
STARTING te NORMANDIE from Cold
1 Overview of propulsion machinery systems
1.1 General Characteristics (from Engineer & Shipbuilder)
From reasons of stability of working,
efficiency and general robustness as well as absence of vibration and noise,
steam turbines with synchronous electrical transmission were chosen for
propulsion. The propelling machinery is arranged over four lines of shafting,
each driven by a three-phase synchronous motor.
Each propulsion motor normally derives its
energy from one of the four main alternating current turbo-generator sets.
Under conditions of maximum economy and at the normal service speed, the
machinery has been designed for a total output of 130,000shp (96,980kW) i.e.
32,500 shp per shaft, with a propeller speed of 225 rev/min.
Under maximum overload conditions, the
machinery is capable of developing 160,000 shp, i. e. 40,000 shp per shaft at
243 rev/min.
The turbines are supplied with steam at
23.5 kg/cm2 (335lb/in2) pressure and at a temperature of about 325C (617F).
Electrical connection between alternators
and propulsion motors is synchronous except during starting or stopping, when
the propulsion motors function asynchronously. During normal connection in
synchronism, the ratio of speed reduction between the turbo-alternator and the
propulsion motor or motors, which it feeds, is fixed and equivalent to 10:1.
The propeller revolutions are thus regulated in accordance with the speed of
the generator, i.e. in accordance with the speed regulation of the turbine.
During normal running at high speeds each
turbo-generator feeds one propulsion motor only. It is, however, at all times
possible by means of mechanically interlocked isolating switches to feed the
motors of the two line shafts on one side by either of the turbo-generators on
that side, thus giving greatly improved efficiency at reduced powers. In no
case is coupling between the turbo-generator sets provided.
Reversing is very easily carried out with
the aid of throw-over switches, the operation of which modifies the connections
between the current generators (turning always in the same direction) and the
propulsion motors fed by these generators.
The fact that the relative positions of the
generators and the motors are not strictly fixed gives considerable latitude
for instalment. The turbo-generator sets are therefore placed close to the
boilers and the turbines are mounted directly above their individual
condensers, resulting in an important saving in the length of steam piping
required. The propulsion motors are placed in a compartment aft, thus
eliminating long lines of shafting and facilitating also the arrangement of the
watertight subdivision of the ship. This separation of the primary and
secondary machines enables the ship to proceed with all its screws running in
the event of the breakdown of a generator.
The simple operation of two-way switches
suffices to isolate the generator that has failed.
1.2 Methods of propulsion generator operation:
1.2.1 Normal Operation:
Four turbo-alternator sets in use providing
an output of 130,000 shp with the speed of rotation of alternators and
propellers respectively being 2,250 and 225 rev/min, a reduction ration of
10:1. One turbo-alternator per shaft.
1.2.2 Maximum power:
Four sets in operation at 160,000 shp, with
corresponding revolutions of 2,430 and 243rev/min respectively. One
turbo-alternator per shaft.
1.2.3. Cruising:
For lower intermediate speeds the following three seperate combinations have been provided:
(a) The four turbo-alternator sets runninig at reduced speed, each feeding its own line shaft.
(b) Two turbo-alternator sets running at reduced speed, each feeding the propulsion motors on two line-shafts with the normal propellers fitted (see c below). The power obtainable is about 60,000 shp normal output at 1,750 rev/min, and 70,000 shp continuous overload at 1,840 rev/min.
(c) Two turbo-alternators running at reduced speed, each feeding the two line shafts. Under this condition special propellers are fitted to give 80,000 shp at about 2,360 rev/min for economical running and about 88,000 shp at 2,400 rev/min under continuous overload.
During the night from June 1st to 2nd NORMANDIE averaged 30,2 kts using only 128,000 hp of indicated 160,000 hp and made up time for a sea water intake in the condensers.
Despite NORMANDIE averaged at 29,98 kts for the 2,907 sm trip from Bishop Rock to Ambrose lightship and reduced the travelling time to 4 days, 3 hours, 2 min.
by
Earl of Cruise
|
The above being an extract from the builder´s information sheet, we will now go on board the NORMANDIE and start her up from cold. For this we need a handful of firemen to start up the requisite boilers, and possible a few junior engineers to help us with the auxilliary machinery. Let´s take a taxi to the ship and have a look around ...
We arrive at the quay and the ship is towering
above us, dark and quiet - no lights or smoke from the funnels as there is no
power on. She looks good though, a true Queen of the North Atlantic - it seems
there is already someone on board waiting for us to get her going.
"Dark and Quiet" te / ss Normandie 29 May 1935 in Le havre Gare Maritime - editors collection
We walk up the gangway and into the First
Class entrance, starboard side on A Deck. Normally we would use the crew
gangway to avoid mixing with the passengers, but today we can have a quick look
at the opulence of this magnificent liner as we pass through to our first task -
starting the emergency diesel generators - so we will use the imposing main
staircase to get from A deck to the Upper Deck.
I hope our engine room boots are clean ...
I hope our engine room boots are clean ...
te / ss NORMANDIE, the Entry Port on A Deck - copy from The Shipbuilder, editing by Stephen Carey, complete deckplan
te / ss NORMANDIE, the Entry Port on A Deck - copy from The Shipbuilder, editing by Stephen Carey
We pass in through the main doors, past the
lifts (we can’t use them as there is no electricity) and walk forward to the
staircase and take the starboard side stairway to the Upper Deck.
We pause to admire this area, which is the main entrance for the more wealthy amongst us to access their cabins and de-luxe apartments, before carrying on up the starboard side of the Grand Stairway to the Promenade Deck - before we get found out loitering in places where we shouldn’t really be -
Take a look around, behind us ...
We pause to admire this area, which is the main entrance for the more wealthy amongst us to access their cabins and de-luxe apartments, before carrying on up the starboard side of the Grand Stairway to the Promenade Deck - before we get found out loitering in places where we shouldn’t really be -
Take a look around, behind us ...
te / ss NORMANDIE, Grand Halle 1ère Classe, Promenade Deck - colouring courtesy Daryl LeBlanc
That´s rather nice, Icould live here under the "vestibule dome" ...
te / ss NORMANDIE to get a glimpse of the dimensions of the Grand Halle 1ère Classe, Promenade Deck - editors collection
te / ss NORMANDIE, WOW! Le Grand Escale, Hollywood and Las Vegas copied this staircase for the grand entrance - colouring courtesy Daryl LeBlanc
te / ss NORMANDIE, Le Grand Salon - colouring courtesy Daryl LeBlanc
Let’s press on ...
te / ss NORMANDIE, Promenade Deck and Emergency Generator Room - copy from The Shipbuilder, editing by Stephen Carey
Exiting out of the starboard side forward
Promenade Deck door, we walk forward past the huge theatre and open the doors
to the emergency generator room for which we have a key, which unauthorised
persons don’t. You can look over the side from here at the people on the
quayside waiting for the lights to come on, so look important and be well
dressed …
te / ss NORMANDIE in Le Havre, Gare Maritime 1935 - colouring courtesy Steve Walker
3 Getting started
3.1 The Emergency Diesel Generators
The Emergency Generator Room houses two MAN diesel generator sets of 150 kW each at 220 Vdc. These engines are compressed air started, with all auxilliary pumps such as cooling water, cooling fan, fuel, lubrication oil, etc. driven by the engine to make them completely self-contained, pretty much like your car. They are also situated high up in the ship to ensure they are not in an area susceptible to damage.
The generators are automatically started when the electrical system senses no voltage on the main bus (the "main bus" means main busbars, which are in effect the live and return cabling similar to that on a car, though the return is not attached to the ship´s side like a car system). However, the switch which would normally start the engines is not in the auto position, so by switching it across, we could allow the engine to start automatically, but this is a bit risky as it is supplied for "warm start" when the main generators fail for whatever reason. We are cold starting, so have to be careful not to damage anything.
Before we start, we have to check the engines over for a sump level, water tank level, battery voltage (for control system) in the same way as you would a car, followed by barring the engine over on the turning gear to make sure there is no water in the cylinders. Having done all that, we can open the fuel valve on the diesel tank within the room and check that the starting air recievers have enough air in them to start an engine. We assume here that they do, otherwise we have a bit of a problem ... Before starting, we need to manually prime the lube oil system, as the engine probably hasn´t run recently. We work the hand pump on the engine until a pressure is shown on the oil pressure gauge.OK,
OK, make sure your earmuffs are on
(probably not available in 1935, but we can do our bit to save our ears - these
things are noisy!) and press the start button. This will energise the starting
air valve solenoid and admit high-pressure air from the air receivers into the
cylinders to rotate the engine.
te / ss NORMANDIE, Figure 7, one of the two MAN 150 kW Emergency Diesel Generators - copy from The Shipbuilder
The engine turns on compressed air and
fires on fuel, running up to speed on the governor. It’s certainly noisy, which
is why it is as far as possible from the cabin accommodation and has insulated
bulkheads. We let the engine settle down and run up to working temperature
before we close the breaker onto the emergency switchboard, which is located in
the same room. Looking at the switchboard we see a number of breakers that will
allow us to feed emergency power to certain sections of the ship. It would be
easy to close them all, but as we need to start up the main boilers and
generators, we need to conserve power to only the necessary lighting to allow
us to see what we are doing in the engine and boiler rooms. We have 300kW
available though; enough to start a 77hp Forced Draft Fan and a 16hp fuel oil
pump for one of the main watertube boilers. As there are 746W to a hp, that equates
to 57kW for the fan and 12kW for the oil pump, a total of some 70kW - half a
generator gone already! However we now know that on one generator we can start
up at least two boilers, with the other generator available for lighting and
anything else we need to start in order to get steam on the main
turbo-generators, such as lube oil pumps, feed pumps etc. We are in for a long
day …
The boiler room fans are on the emergency
circuit via the main bus, as can be seen from the ship’s single line diagram
(SLD) - right hand side, reproduced below. We will see the left hand side of
this drawing later -
te / ss NORMANDIE, Figure 8, Emergency side of Single Line Diagram - copy from The Shipbuilder
Here you can see circled at left, the
boiler room fan breakers, which we will need to close, and also the boiler room
pumps breaker (via the engineroom pumps panel) to put power on for the oil
pumps. However these breakers are off the main bus, so we will close those
later when at the main switchboard down below. For now we just close the
emergency feed to the main bus systems via the interlocking switch. As if by
magic, the emergency lights come on!
Top right on the drawing can be seen the
two emergency generators, the emergency switchboard and the 24V control
switchboard. With these breakers closed, we can work our way down to the bowels
of the ship and make her come alive.
Before we leave the EDG room we check the
levels in the emergency generator fuel tanks - great, 24 hours at least, though
we won’t need them for that long - and make sure the battery charger is working
on the control system. This is important because once switched to auto, the
emergency generators will automatically battery start on loss of power on the
main bus and put themselves on the board to provide lighting - besides the
passengers not liking being in the dark for more than a few seconds, items such
as navigation lights, steering gear and radio operate off the emergency
generator. In this ship with 6 main generators and 29 boilers, there is so much
redundancy that a “black out” is a very remote possibility.
Let us now proceed to the boiler rooms and
engine rooms for a look round. As this is a fancy passenger ship, you can wear
your company cap with your uniform if you like, in case we run into the Chief
Engineer, though I will wear a boiler suit in case I get dirty. No hard hats
are necessary as no one is likely to drop anything on our heads and in any
case, PPE isn’t invented yet; we even have to buy our own uniforms, boilersuits
and boots, as it will be some decades before owners buy them for us. Union
Power ...
3.2 Going "Down Below"
To get to the machinery spaces we have a
long way to go and there are several ways of getting there. We will head down
the staircase forward of the theatre and go down the restricted staircase for
the crew access to each deck. This turns out to be an enclosed white-painted
shaft going down and down. And down. Our boots echo on the stairways in the
silent ship, with the faint hum from the EDG gradually disappearing as we go
down through 6 decks to E Deck, to a door which says something like “Aucune admission au personnel non autorisé”,
but we are authorised personnel and we go through the door into the fan area
above the silent forward boiler room. Here we can see the forced draft and
ventilation fans ready to supply air to the boilers. Again our boots clatter on
the rungs of the ladders down to the boiler room floor plates, where we stand
in amongst the main power generation equipment of this huge liner - the steam
generating plant main boilers in the forward boiler room. There is a faint
smell of new paint and fuel oil in the air, which all boiler rooms have, given
off by the fuel pumping plant and hot lagging round the steam pipes once steam
is raised - this room is as big as a cathedral; a cavernous echoing space. Take
a moment to look around you and up into the uptakes above us.
te / ss NORMANDIE, Figure 9, Down - down - down below - collection Stephen Carey, complete cutaway
3.3 Boiler rooms
NORMANDIE has four boiler rooms arranged from forward to aft, containing 29 water tube boilers and four Scotch boilers.
The boilers in this boiler room and auxilliary machinery items are arranged as follows - figures in colum 1 show the plate reference numbers for the drawings that follow. It is best to print a copy of the plates as a reference when going through the tables and for the walk-round we are doing.
3.3.1 Boiler Room 1: Ref.
|
Qty
|
Designation
|
A1 to A4
|
4
|
Main water tube boilers
|
C
|
2
|
Main oil-firing units
|
D
|
2
|
Underwater sewage ejectors
|
E
|
3
|
Main forced-draft fans
|
F
|
2
|
Ventilating fans
|
te / ss NORMANDIE, Figure 10 Boiler Room 1, Plan - copy from The Shipbuilder
te / ss NORMANDIE, Figure 11 Boiler Room 1, Elevation - copy from The Shipbuilder
We will pause here to start firing the
boilers, as it is usually better on a dead ship to light the forward-most
boilers first, with the main stop open to the main steam lines in order to
bring up these lines - which pass right through the watertight bulkheads to the
turbo-generator rooms - together with the boiler rising pressure. In this way,
the main steam lines can be warmed through and drained of condensate, which
would otherwise damage the steam turbine machinery. There are drains on these
lines at various points along the length of the piping.
We need firemen for this job, and they are
luckily on hand waiting for us to give the go ahead.
From the view below, you can see that the
boiler room is in immaculate condition, unlike the stokeholds of the coal
burners in the earlier ships of this series of cold-starting notes. We will
open the drains and “steam traps” as we walk through the spaces. A steam trap
will allow automatic draining of condensate from lines to negate having to
stand and watch them whilst they are draining, though there is a bypass to
allow quick - attended - draining; wasting feedwater/condensate is frowned upon
on steam ships. Condensate or “condensed feed water” is liquid gold on a steamship,
so these drains are collected in tanks and returned to the feedwater tanks.
Most steam engineers even begrudge the Master using the steam whistle overmuch!
te / ss NORMANDIE, Figure 12 Boiler Room 1 - editors collection
Here you can see yourself facing forward in
your smart uniform checking out the general condition of the boiler systems. To
your left (port side) is the oil-burning pump set for these boilers, which we
will soon be starting up. In front of and behind you are two of the boiler
fronts, with the four square burner panels visible on each, along with the
white-lagged fuel rail. You can see the lagging on some of the steam pipes, and
the white circular covers over the bottom drums of the watertube boilers. The
fuel oil heater - the black drum - can be seen in the background, and there are
two more boilers to your right (starboard).
We use a boiler room phone to call the main
switchboard (where an electrical engineer is in attendance) and ask him* to
close the breakers for the forced draft fans and the oil pumping systems in this
compartment.
*Note:
|
There was only
one female engineer at sea in those days, and not on this ship either as she
was ashore in 1935 running a business with her sister - see Victoria
Drummond.
|
We then instruct the firemen to start up
the boiler oil pump and start circulating the oil from the fuel oil settling
tanks to the pump suction strainers and into the pump, which then discharges
through the heater. The firemen will use the small electric heater and pump
unit for starting the system because we have no steam available for the main
heater; it’s known as a “cold start” pump and heater. Hot oil is now available
at the boiler burner rail. The pump pressurises the rail to around 16bar by
means of a pressure-regulating valve (PRV), to ensure that the burner rail
pressure remains constant at all times. From the PRV the fuel goes back to the
pump suction upstream of the heater. The pump capacity is some 16.7m3/hr or
15t/hr, which is 360t per day delivery, though actual consumption would be less
than that. Here’s a sketch of a typical boiler fuel circulation diagram -
te / ss NORMANDIE, Figure 13 Typical boiler fuel oil circulation diagram
The fuel comes from the settling tank and
via a suction strainer into the fuel pumps, which discharge it through the
heater and fine filter to remove any impurities that may block the burner tips.
Whether Normandie had a Viscosity Regulator is not known, but this device if
fitted would measure the fuel viscosity and either increase or decrease the
heat applied by the heaters. Normandie didn’t have a diesel supply for cold
start either or, if she did, it’s not mentioned in any publication. The fuel
then enters the fuel rail which supplies all the burners in the boiler system,
with a spur to the other boilers supplied by the same pumping system. The
pressure builds up in the line, and is vented via the back-pressure valve - or
a manual valve as shown in the diagram - back to the pump suction. It is likely
that with so many boilers, Normandie would have an automatic pressure regulator
to keep the fuel pressure steady at 16bar.
Whilst this is happening, we climb the
ladders to the top of the boilers in the forward boiler room and open the main
stops, which are the isolation valves from the steam drum and superheater. At
the same time we open the superheater-starting valve so that when steam is
raised there is a path through the superheater tubes to avoid them overheating
before we can get a turbo-generator running (this is just a valve that leads
the steam to the bilge - it makes a racket, though is sometimes fed through a
silencer). We then go to the electric starter for the forced draft fans “E” and
the ventilation fans “F” and start them up - it’s quite noisy and we have
trouble hearing each other once they are going. The fan speed can be regulated
to match the draft with the oil quantity to allow smoke-free combustion - and
the firemen will control the oil and air volumes to the furnaces as required.
As we are starting up from cold, it will take some hours to gradually raise
steam on the boilers. We will start with around ten minutes of firing every
half hour and gradually increase this as the boilers warm through and start to
make steam. Raising steam too quickly could cause thermal shock to the boiler
internals, which is obviously to be avoided. The Leading Fireman knows what he
is doing, and we can leave him to do the job.
te / ss NORMANDIE, Figure 14 fireman tending the fires on the burner front - editors collection
te / ss NORMANDIE, Figure 14 a fuel oil pump (one of ten) - editors collection
The fireman’s job is a lot easier on an
oil-burner compared to a coal-burner in that he doesn’t have to shovel coal,
discharge huge quantities of ash or clean fires every watch, which is a filthy
job and very labour intensive. Our fireman above is firing using one of the
main burners to warm through, and will cycle through them one at a time to warm
the internal brickwork and tubes up evenly. With careful control of the
combustion air and fuel, he can ensure a clean flame which is not only more
efficient in burning the oil, but also keeps the boiler internals clean which
aids in the transfer of heat from the flame to the water tubes. Dirty tubes can
cause local hot spots, which can result in a tube cracking or bursting. Even on
an oil-burner the fireman’s job is still very important and it takes a skilled
man to watch the water levels, steam pressure and flame condition. He also has
to know when to withdraw a burner and replace it with a clean one if the oil
vaporisation is starting to get ragged. This would cause excessive smoke, which
is to be avoided for both boiler condition, fuel economy and passenger comfort!
The silence in the boiler room is now a
thing of the past - the noise of the forced draft fans and ventilation fans
fills the room, the roar of the flame inside the boiler and the flickering
light through the furnace sight glass is evident in all the fired boilers. The
fuel-pumping unit is humming away feeding the furnaces with fuel, and there is
a smell of hot lagging permeating the space. We are starting to get things
going and will move aft through the other boiler rooms to the turbo-generator
room and propulsion room.
Note:
|
The term
“turbo-alternator” is used for this ship only for the propulsion units, as
they are synchronous units - i.e. alternating current. Nowadays the term
“alternator” is relegated to automotive use, marine systems being termed “AC
Generators” or “DC Generators”. The book used for information terms these
“turbo-alternators” and “turbo-dynamos” respectively, so we will stick to
this terminology as used on the ship in service. The term turbo-generator is
used when generally referring to all the generating machinery.
|
After checking that all is well in Boiler
Room 1, we walk aft through the watertight door into Boiler Room 2, leaving the
heat and noise behind us and into a relatively quiet area.
Again the firemen are standing by, and we
instruct them to start warming through in the same way as Boiler Room 1, but in
this case we leave the stop valves shut to the main steam piping.
In the drawings that follow, we can see
that the equipment in No 2 is similar to that in No 1, though there are 9 main
boilers in the space, so it is much bigger. In fact, it’s enormous and seems to
go up and up forever above the boiler uptakes
The oil-pumping unit in this boiler room is
situated between boilers A8 and A11, and there are six forced draft fans plus 4
ventilating fans to be started in this room. However, we don’t have enough
power to start all these, so will use one set to get each boiler warmed through
and up to pressure against the stop. If this is too much for the emergency
generator, we will leave these units until we have a turbo-dynamo running,
which will allow us to start up all the boilers - there’s no rush!
Notice the “snake-pit” of piping above the
boilers in this room. There are four main steam lines, and the “omega bends” in
the piping are there to allow for expansion as the superheated steam passes
through the lines. You can see where these four lines pass through the after
bulkhead into Boiler Room 3.
3.3.2 Boiler Room 2
Ref
|
Qty
|
Designation
|
A5-A13
|
9
|
Main boilers
|
C
|
3
|
Main oil-firing units
|
F
|
4
|
Ventilating fans
|
H
|
1
|
Ballast pump (10t)
|
I
|
1
|
Bilge pump (300t)
|
J
|
1
|
Wash-deck and fire-main pump
|
Besides the main boilers, ventilating fans
and oil-firing units in this space, we can take a few moments to look at the
ballast pump “H” at the forward end of the room just off the centreline to
port, and the bilge pump “J” on the forward bulkhead starboard. The ballast
pump is used to pump seawater in and out to balance the ship for list and trim,
and it may be that in this ship, and judging by the small capacity of this
pump, the fuel tanks were used for ballast when empty of fuel in order to keep
the trim constant. This once common method of “seawater compensation” is now
out of the question owing to the risk of polluting the oceans with oil.
The bilge pump is used to pump the contents
of the bilges out over the side. The bilges are the lowest part of the
machinery spaces and the bilge wells normally occupy a portion of the double
bottom, thereby allowing any oil, fuel and water drains to end up in the lowest
point of the ship, from where it can be pumped overboard.
Note:
|
Nowadays it is
forbidden to pump bilges or any oily waste overboard from ships unless it has
passed through an Oily Water Separator first, to ensure that anything that
does go over the side is at less than 15ppm oil in water. Bilge tanks are now
supplied such that all drains can go to separate tanks, which make the bilges
a lot cleaner than they were in 1935, though on a prestige liner such as
Normandie it is likely that the Second Engineer will keep the bilges as
pristine as the floor plates shown in the photographs.
|
te / ss NORMANDIE, Figure 15 Boiler Room 2, Plan - copy from The Shipbuilder
te / ss NORMANDIE, Figure 16 Boiler Room 2 – Elevation - copy from The Shuipbuilder
We’ll carry on with our walk through the
boiler rooms into Boiler Room 3. Again the room is enormous and houses a mass
of machinery. There are 5 main watertube boilers in this space, plus 4
cylindrical Scotch fire-tube boilers of which more later. Again we will not
fire the boilers in this space owing to lack of power, so will have a look at
the general machinery lay out as we walk through the watertight door at the
after bulkhead.
3.3.3 Boiler Room 3 Ref
|
Qty
|
Designation
|
|
A14-a18
|
5
|
Main boilers
|
|
B
|
4
|
Scotch cylindrical boilers
|
|
C
|
2
|
Main oil-firing units
|
|
D
|
2
|
Underwater sewage ejectors
|
|
E
|
4
|
Main forced draft fans
|
|
F
|
4
|
Ventilating fans
|
|
G
|
2
|
Forced-draft fans for Scotch boilers
|
|
I
|
1
|
Bilge pump (300t)
|
|
K
|
2
|
Transfer pumps
|
|
L
|
2
|
Hot-water tanks
|
|
M
|
4
|
Saltwater
heaters
|
|
N
|
2
|
Circulating
pumps for hot fresh water
|
|
O
|
1
|
Oil-firing
unit for Scotch boilers
|
|
P
|
4
|
Evaporators
|
|
Q
|
2
|
Evaporator
feed units
|
|
R
|
1
|
Reheater
for Scotch boilers
|
|
S
|
2
|
Feedwater
pumps for Scotch boilers
|
|
T
|
1
|
Lower
secondary feed tank
|
|
U
|
1
|
Secondary
feed filter
|
|
V
|
1
|
Upper
secondary feed tank
|
|
W
|
1
|
Air pump
|
|
X
|
1
|
Circulating
pumps for auxiliary condenser
|
|
Y
|
1
|
Auxiliary
condenser
|
|
Z
|
1
|
Pump and
tank for filter
|
|
R1
|
1
|
Ash hoist
|
|
N1
|
2
|
Circulating
pumps for hot salt water
| |
In 1935 it was the practice to discharge
sewage straight over the side of the ship, and this practice continued for many
years after until the MARPOL (Marine Pollution) Act was ratified around the
late ‘70s. In this compartment there are two sewage ejectors “D” which discharge the sewage away from the ship
underwater. This is a lot better than discharging it on the waterline though,
where sewage discharge could end up in one of the tenders carrying passengers
ashore … There is one sewage ejector to port, and one to starboard.
The Transfer
Pumps “K” situated
port aft inboard of boiler A18 are used to pump boiler fuel from the storage
tanks to the settling tanks. These tanks can be seen outboard, port and
starboard, forming the double sides of the machinery spaces.
When the oil is bunkered from a barge,
there is water and contaminants in it, which would affect the burning of the
oil and tend to block the burner tips. Whilst it is not necessary to clean the
oil to any great degree (as would be required for a diesel engine for
instance), the oil in the settling tanks allows water and dirt - which are
heavier than the oil - to drop to the bottom of the tank clear of the suction,
from where it can be “sludged off” by opening a sludge cock. The suction
strainers and discharge filters of the oil-burning units remove any further
impurities from the oil (Figure 13).
The hot
water tanks, seawater heaters and pumps “L”, “M”, “N” are for domestic
use. Ships of this vintage normally had salt-water baths for lesser mortals, which
were actually rather nice, like a hot spa! They used special saltwater soap as
normal soap won’t lather in seawater. A large jug of fresh water was provided
(by your steward) to pour over yourself afterwards to rinse off the salt suds.
The pumps pressurise the water mains throughout the ship, and also supply
seawater for flushing toilets and urinals. Fresh water baths and showers were
probably also available in First Class, but we don’t need to concern ourselves
about that, other than to make sure the fresh and salt water hot water
circulating pumps are running once we get on to main power. The stewards get a
hard time of it from passengers if there is any malfunction in the water
supplies and temperature, which is rather unfair to them as it all comes from
the engineering department!
The evaporators
“P” are used to make fresh water out of seawater, using steam to
evaporate the seawater with the steam given off being condensed via cold
seawater in a shell and tube cooler. The water so produced is very pure, and is
used solely for boiler water where purity is paramount, especially in watertube
boilers. Domestic/fresh water would be bunkered from ashore in each port, as
the ship was only intended for transatlantic crossings, though the evaporators
could augment this. Nowadays ships have a fresh water generator, which produces
fresh water more economically via flash evaporation (using waste heat and
vacuum) or reverse osmosis.
The remaining feed heaters and equipment
are for use with the Scotch boilers, of which more later.
There is an ash hoist “R1” in this
compartment, but as this ship was built as an oil burner, it’s not clear what
this is for - resistance to change? Plus ça change …?
te / ss NORMANDIE, Figure 17 Boiler Room 3, Plan - copy from The Shipbuilder
Figure 18 Boiler Room 3, Elevation - copy from The Shipbuilder
Again, we will not be starting anything up
in this boiler room until we are on main power, so we will walk the length of
the space and exit via the after watertight door. Note that in ships such as
these, the watertight doors are open all the time in order to allow working
access to the spaces. In the event of damage, they can be closed in a few
minutes to seal off the spaces from each other to lessen the effects of
flooding in any compartment. Access to and egress from the spaces is then by
ladder to the upper decks.
Exiting out of Boiler Room 3, we come to
Boiler Room 4, another huge space containing no less than 11 watertube boilers
- 9 in three rows of three forward, and two at the after end, port and
starboard.
3.3.4 Boiler Room 4 Ref
|
Qty
|
Designation
|
A19-A29
|
11
|
Main boilers
|
C
|
3
|
Main oil-firing units
|
D
|
2
|
Underwater sewage ejectors
|
E
|
8
|
Main forced draft fans
|
F
|
4
|
Ventilating fans
|
R1
|
1
|
Ash hoist
|
S1
|
6
|
Main feed pumps
|
T1
|
2
|
Feed pumps for turbo-generators
|
U1
|
4
|
Main low-pressure feed heaters
|
V1
|
4
|
Main high-pressure feed heaters
|
W1
|
4
|
Coolers for main drains
|
X1
|
1
|
Low-pressure feed heater for turbo-generators
|
Y1
|
1
|
High-pressure feed heater for turbo-generators
|
Z1
|
1
|
Cooler for turbo-generator drains
|
te / ss NORMANDIE, Figure 19 Boiler Room 4, Plan - copy from The Shipbuilder
te / ss NORMANDIE, Figure 20 Boiler Room 4 - Elevation - copy from The Shipbuilder
In this boiler room are situated parts of
the feedwater system, which will be discussed later as we start to energise the
main equipment ready for sea. Otherwise the equipment is more or less the same
as in the other boiler rooms.
A few notes on the fuel oil arrangements of NORMANDIE
3.3.5 Oil bunkers
The boiler oil fuel bunkers are arranged in
the double sides outboard of the boiler rooms, and comprise 12 storage tanks on
the starboard side, and 13 storage tanks on the port side. There are 4 settling
tanks inboard of the storage tanks outboard of Boiler Room 3. The latter
separate oil from water and other solids by gravity, and are regularly sludged
to remove the water prior to it being pumped to the boiler oil-firing
apparatus. The oil-firing or burner pumps are arranged between each pair of
Yarrow boilers.
3.4 Turbo-dynamo, turbo-alternator and auxiliary engine room
Continuing our walk through the ship, we
exit via the watertight door in the aft bulkhead of boiler room 4, and find
ourselves on the lower level of the turbo-dynamo and turbo-alternator room.
This is another large space containing a mass of machinery, all of which
supplies electrical power for propulsion as well as hotel and other services.
The main rooms are on two levels, so we will go up the stairs to the upper
level, eventually moving aft to the main switchboards and the manoeuvring
platform, from where the engines are controlled. This is a nice clean space,
light and airy, with the machinery well kept and painted in light colours to
improve visibility. It’s silent at the moment, apart from the odd drip of
seawater into the bilges from leaking pump glands and valves, but otherwise
“the calm before the storm” once all ten turbines are running. We will start a
ventilation fan for this space, and hope that the emergency generators won’t
trip… (Well, the lighting flickered a bit, but we didn’t trip the generators,
so all well and good!)
te / ss NORMANDIE, Figure 21 Engineer Officers in the turbo-dynamo room - editors collection
The picture shows the engineering staff
standing between the two inboard turbo-dynamo units. These are the units that
supply main power to the switchboards for our machinery systems, but are not
the power units for propulsion. Even so, these are large items of equipment,
and there are six of them in this compartment. The large piping in the form of
a “suitcase handle” at the end of the room are the exhaust bends from the hp to
the lp main propulsion turbines which make up each turbo-alternator unit, so we
are facing aft in this photograph.
Another photograph of the space without the
engineers shows the sheer size of the generating units, which stretch the whole
length of the room. Again the exhaust bends of the propulsion alternator turbines
can be seen in the distance at the after end of the room.
te / ss NORMANDIE, Figure 22 Turbo-dynamos with Propulsion units aft - editors collection
Situated aft of Boiler Room 4, this room
contains the electrical power generation machinery and auxiliaries.
For all electrical services, 6
turbo-dynamos are fitted (shown within the green rectangle, Figure 23). Each
dynamo is driven by a steam turbine prime mover and comprises 6 sets of hp and
lp turbines, condensers, circulating pumps, condensate pumps and vacuum
augmenters. These are the units that we will be shortly starting up, in order
to get us from emergency power to main power. We can spend some time getting
things ready in this area whilst we wait for the boilers to come up to
pressure.
Also in this room at the after end are the
four turbo-alternators (shown within the blue rectangle), which are the
propulsion units, of which more later. The equipment installed in this
compartment at the forward end between Frames 135-145 is tabled after the
drawings of the Lower Platform Level.
te / ss NORMANDIE, Figure 23 Turbo-generator Room, Upper Platform Level Plan - copy from The Shipbuilder, editing by Stephen Carey
Having a look round here, in conjunction
with the picture taken looking aft shown earlier, we are standing just above
the steps down into the propulsion alternator space, with the two inboard
turbo-dynamo units either side of us. Now that a ventilation fan is running you
can see where the air is distributed on the drawing above, by the arrows shown
on the trunking. It’s adding a bit of noise to the space and you can feel the
air circulating through the room.
Our first job here is to go back down to
the lower platform level and start attending to the auxiliaries we need to get
a turbo-dynamo going.
te / ss NORMANDIE, Figure 24 Turbo-generator room - lower platform level Ref - copy from The Shipbuilder
Qty
|
Designation
|
|
20
|
6
|
Turbo-dynamo units
|
21
|
6
|
Condensers
|
22
|
6
|
Circulating pumps
|
23
|
6
|
Condensate pumps
|
24
|
6
|
Vacuum augmenter
|
25
|
1
|
Hotwell tank
|
26
|
6
|
Feed regulators
|
27
|
2
|
Sea induction valves
|
28
|
2
|
Seawater overboard discharge valves
|
29
|
6
|
Returned oil tanks
|
Down here you can see at the forward end,
the watertight door that we came through from the boiler rooms. There is a mass
of machinery and piping in this area, all of which is to serve the
turbo-dynamos (20). Slung under the turbines we saw on the upper level are the
condensers (21), one for each turbine unit. These are provided to condense the
steam issuing from the exhaust of the turbine sets in order to drop the
pressure and extract the maximum energy from the steam. To achieve this vacuum,
the steam passes round a tube bundle in the condenser (21) through which passes
cold seawater, which condenses the steam into condensate, which drops to a well
at the bottom of the condenser. We will get things going here by starting one
seawater pump (22), but before we do that we have to go outboard to the
seawater inlet and discharge valves and open them up. We crack open the
discharge first (28), and then open the inlet valve (27) fully. Going across to
the seawater pump starter, we press the start button (which starts the pump at
low revs) and gradually increase the speed. Whilst you are doing this, I open
the discharge valve fully (the reason for throttling the discharge is so that
the centrifugal seawater pump starts on no load). The pump runs up to full
speed and we check that the seawater pressure is satisfactory on the attendant
gauges for suction and discharge pressure.
te / ss NORMANDIE, Figure 25 Dynamo condenser seawater circulating pump - editory collection
There is another item, which is the “vacuum
augmenter” (24), otherwise known as a vacuum pump, whose purpose is to remove
non-condensable gases from the condenser, mainly air and CO2 in order to
improve the vacuum created by the condensing steam. For this to work however,
we need steam, so we check with the main steam line pressure gauge to see if we
have pressure up on the line. As it’s some time since we fired the boilers up
forward, we find that the steam pressure is indeed now up to 28kg/cm2 in the
main lines. This is a much higher pressure than the earlier ships of the
series, and the superheaters in the boilers will raise the temperature of the
steam above saturation temperature to 350C. The temperature of dry saturated
steam at this pressure is 231C, so this corresponds to 119 degrees superheat
(i.e. degrees above saturation temperature). Superheating makes the energy
delivery more efficient, and the steam is dry, with no condensate forming once
the lines are up to temperature.
te / ss NORMANDIE, Figure 25 a sectional arrangement of Turbo-generator - copy from The Shipbuilder, editing by Stephan Carey
Here we see a longitudinal section of the
turbo-dynamo. On the right is the turbine driver with its control valve (on the
end at the top), governor and gland steam system.
The turbine blading is encased in the
“cylinder”, with steam passing and expanding through the blades from right to
left, such that it drops in pressure at each stage, finally exhausting to the
condenser at a vacuum (induced by the condenser as mentioned earlier).
In the centre is the single reduction
gearbox, which reduces the turbine speed at the input down to the generator
speed at the output, from 5180 to 530rev/min, or a reduction ratio of around
9.8:1.
To the left is the actual electrical
generator, whose rotor and stator produce 220Vdc at the terminals. This
turbo-dynamo produces a full load power of some 2.2MW, so it and its other 5 fellows
can produce 13.2MW, though four are used in service with two spare.
4 Starting a main turbo-dynamo
Starting the turbine for the first dynamo
we will be putting on the switchboard is a bit of a juggling act. We have to
make sure the steam is dry to avoid damaging the blading; we have to start
auxiliary pumps (with limited emergency power as mentioned earlier); we have to
start steam auxiliaries such as feed pumps and condensate pumps (23). We have
already started a seawater pump above, and this is consuming 39.8kW of our
emergency generator supply. We need main power as soon as possible.
First we go to the main steam stop valves
on the forward bulkhead and check the drains to ensure there is no water in the
lines. Up forward the firemen are standing by on the fires ready for us to
start using steam. As steam is used in the generator, the boiler pressure will
start to drop so the firemen will keep an eye on the boiler level, the steam
pressure (maintained by adding more burners if required) and closing the
superheater starting valve once the generators are running on superheated
steam. This valve is blowing off to the bilge all the time the boilers are
fired; it makes a racket and is a blessed relief once it’s closed.
A typical generator start up routine is -
1. Check that we have a small amount of
water in the bottom of the condenser to ensure that the condensate pumps will
have suction. The condensate pumps draw water from the condenser as it evolves
from the condensed steam. The level in the condenser is maintained by an
automatic regulator that works off the condenser level, returning the water to
the condenser or to the feed tanks as required. If there is no water (we will
assume there is) more can be added from the feed tanks or heaters under gravity.
2. Re-set the emergency governor. This will
have been tripped to stop the generator when it was last used.
3. Open all drains (main steam stop valve, turbine cylinder, main steam strainer).
This will ensure there is no water collected in the cold piping as it comes
into contact with the steam from the main lines.
4. Start condenser circulating water plant
(seawater pump), which we have already done
5. See that the motor-driven oil pump
starter switch is in “on” position. Start the pump and allow the oil to
circulate through the turbine, gearbox and generator bearings. Once we are up
to speed, the engine-driven LO pump will supply the pressure, and this pump can
be set to “auto”. It is used if there is a trip of the generator in service,
automatically starting to supply lube oil as the turbine runs down to a stop.
6. Open cooling water valves to oil cooler
and generator air cooler. This will circulate seawater through these coolers.
The oil and air gets hot as the generator loads up.
7. Start the condensate extraction pump;
this uses 3.5kW of our dwindling emergency supply. The pump will circulate the
condenser water via the regulator valve back to the condenser. Once the
condenser starts to fill to the set level, the regulator will redirect the water
to the feed system.
8. Turn gland leak-off 3-way cocks to
engineroom leak-off, and then seal the glands. The glands are at the ends of
the turbine shaft, and if left unsealed, will allow steam to flood out of the
ends of the shaft - not good. They also prevent air being drawn in under the
vacuum at the low-pressure end.
9. Turn on steam supply to the air pump
(“vacuum augmenter” secondary jet). This will start removing non-condensables
out of the condenser and improve the vacuum.
10. Open stop valve slightly to warm
turbine. This will allow steam to flow slowly into the turbine and start to
warm up the blading and casing. This is important in order to allow the turbine
to expand to its working condition. Too fast and the blades will bind on the
stator - not good.
11. When vacuum has reached 20 inches, open
the stop valve until the turbine starts to turn, closing it somewhat
immediately afterwards to prevent the turbine gaining speed too rapidly.
12. Gradually speed up, then keep turbine
running at about half revolutions (2500rev/min) for ten minutes, then bring it
steadily up to full speed in not less than five minutes. At full speed, the
speed governor will come into action and take control of the machine. Open the
stop valve fully. The machine is now whirring away (quite quietly), and we
check round all the gauges to make sure all is OK - oil pressure, steam
pressure and temperature, vacuum (very
important), and all bearing temperatures.
13. Stop the auxiliary motor-driven oil
pump, and switch to ‘Auto’ control so that it starts if we get a turbine trip.
Normally we would test the trip at this stage to make sure the control system
works.
14. Vent the condenser and vacuum pump
circulating water spaces and check condenser water level is being regulated properly.
15. Turn on steam supply to vacuum pump
primary jet. Adjust this to give the best vacuum with lowest possible steam
pressure.
16. The turbine is now running “straight
condensing” in that the steam is passing through the blading and exhausting to
the condenser, where it is condensed into feed water.
17. Shut off the external gland steam
supply and open the valve controlling gland steam leak-off into the turbine to
reduce the leak-off to the engineroom drains.
18. Set the speed at about 5200rev/min to
allow for some speed drop when load is applied. This will give a speed at the
generator end of 530rev/min.
The turbine is now running under the
governor, and we can call the main switchboard for the electrician to apply
electrical load on the board by closing the dynamo circuit breaker. We can send
one of the junior engineers up top to stop the emergency generators and make
sure they are switched to automatic in case we lose power on the main bus.
The engine room is now starting to come
alive, with the hum of the dynamo and the noise of the seawater circulating and
condensate pumps.
We can call the boiler room and let them
know that they can close the superheater starting-valve. There is now enough
power to get as many boilers on line as we require for going to sea but before
we do that, there are some other important things needing our attention in
order to keep things going.
te / ss NORMANDIE, Figure 26 Starboard Inner Turbo-dynamo set - editors collection
Here’s our turbo-dynamo set, running
relatively quietly. The turbine is at the left hand side (forward), with the
generator on the right (aft). The gearbox is shown in the middle. The condenser
and pumps are mounted underneath - the ladder in the foreground goes to the
lower level. If required we now have all we need to start a second or more
dynamos depending on the load. The firemen can now start all the forced draft
and stokehold ventilation fans, change over from electrical heating to steam on
the fuel oil heaters and use the large full power fuel oil pumps. The “cold
start” oil pump and heater can be shut down. The boiler stop valves are opened
as required depending on the steam pressure in the main piping.
5 The Feedwater and Condensate system
This important system covers the closed feed system of a large steam plant. The system and its auxilliaries carry out the following basic operations:
1) To pump water into the boilers to maintain the levels
2) To extract the condensate from the condensers
3) To maintain the level in the condensator
4) To use exhaust steam and hot returns to heat the feedwater so produced
5) To filter any oil/grease out of the water prior to pumping back to the boiler
The feed and condensator system is designed to extract the maximum energy from the steam and return the heated feed water back to the boilers at the maximum design temperature. There is little or no information about NORMANDIE´s feed condensate and drain systems, so we will have to rely on experience to figure things out.
there atre two feed systems on the ship, one for the turbo-dynamo system and one for the main propulsion turbo-alternators. We will cover the dynamo one first otherwise we will run out of water in the boilers, so we need to be quick in continuing our juggling act.
te / ss NORMANDIE, Figure 27 one of the Dynamo Turbo-feed pumps - editors collection
The turbo-feed
pumps “T1” are compact units; in the picture at Figure 26 the steam turbine
is on the left with the multi-stage centrifugal pump on the right (note that a lot of equipment in passenger
ships of the era was British made, as befitted the then premier shipbuilding
nation of the world).
These pumps, along with the larger
propulsion feedwater pumps, are situated at the after end of Boiler Room4, so
we have to duck back through the watertight door at the forward lower level of
the turbo-dynamo room and into the boiler room where we will find two of these
pumps, “T1” on the drawing in Figure 19 and Figure 20. To start this pump we need to drain the steam
lines as usual to avoid damaging the turbine, and line up the exhaust to the LP
and HP feed heaters “X1” and “Y1” above the pumps in order to heat the
returning feedwater to the boilers.
Opening up the control valve to admit steam, the turbine runs up to
speed, exhausting through the heaters to the drains cooler and delivering
feedwater from the feed tanks to the boiler level controllers. By this time the boiler levels will have
dropped somewhat, and our firemen will be relieved to see the water levels
begin to rise. The feed pump will run
just about unattended, as it is fitted with a discharge pressure operated governor: If the feed demand is zero (i.e. all the
boiler level controllers are closed) then the discharge pressure will rise and
act on the governor to reduce the speed of the turbine (in practice once at
least one turbo-dynamo is running, there will always be some demand on the pump
in a closed-feed system), and conversely as the boiler levels drop, the feed
controllers will open, reducing the discharge head and speeding up the turbine
accordingly. Inherent stability of
operation is a feature of the Weir (and its close cousin, Coffin) feed
pumps. The pumps can deliver 75m3/hr of
feedwater to the boilers at 36.5kg/cm2 pressure (to overcome the boiler
pressure of 28kg/cm2).
From the boilers the steam passes to the
turbo dynamos. Steam from the dynamo exhausts
that has condensed into the hotwells under the condensers is returned to the
feed system using the sets of condensate
pumps “23” located at the lower platform level (Figure 27).
te / ss NORMANDIE, Figure 28 Longitudinal view of turbine room - copy from The Shipbuilder
These electrically driven pumps draw from
the bottom of the condenser well and deliver the condensate either back to the
condenser to maintain the level via the level
controller, or to the feed tank
“25” in Figure 27. They are similar in
type to the main condensate pumps, though smaller in size.
The turbo-dynamo
feed pumps “T1” – two sets - located in Boiler Room 4 (Figure 19 and Figure
20) draw the water from the feed tanks and discharge it through the feed
heaters, which use various drains, bled steam from the turbines and exhaust
steam from auxiliary systems to heat the feed water. The first stage (LP) uses auxiliary exhaust
steam supplemented by bled steam from the turbine at 0.5kg/cm2, whilst the
second stage (HP) utilises bled steam only at a pressure of 2.5kg/cm2. The feed – at high pressure – passes through
the tube nest, whilst the heating steam passes through the shell.
From the high pressure feed heaters “Y1” the water passes into the boiler
feed main, from where it is fed to the boilers by automatic feed regulators
working off the boiler level. The
turbo-dynamo feed pumps run in conjunction with the main feed pumps for the
propulsion feed system mentioned later.
The exhausts from the feed heaters, after transferring their heat to the
feed, pass via a drains cooler “Z1”
and thence back to the drains collection system.
We now have a stable system running, with
the steam from the boilers supplying the turbo-dynamos, the returns from the
condenser passing via the turbine driven feed pumps, through the LP and HP feed
heaters and the back to the boilers. Our
juggling act has come to fruition without dropping any balls… We can now turn our attention to the main
propulsion system, and get it ready for sea service. Things are starting to hum along quite
nicely.
6 Main propulsion turbo-alternators
We are now up and running with all systems that we need to start the main propulsion. there is no physical link between the power to drive the ship (the turbo-alternators) and the propulsion motors that actually drive the shafts, other electrical cabling. This is novel in that the two systems may be placed conveniently without any need for shafting connections as in direct drive or geared turbine propulsion units
To dive the motors we first have to start the turbo-alternators in order to supply the power for the motors. The main turbines - of which there are four - are very similar to the dynamo sets that we started, so the two systems complement each other.
te / ss NORMANDIE, Figure 30 Lower platform level - copy from The Shipbuilder
First we will get a main seawater
circulating pump going for which we need to open the seawater induction and
overboard valves.
Ref
|
Qty
|
Designation
|
1
|
4
|
Turbo-alternator hp turbine
|
2
|
4
|
Turbo-alternator lp turbine
|
3
|
4
|
Main Propulsion Alternator
|
4
|
4
|
Condensers
|
5
|
8
|
Main Sea Circulating pumps
|
6
|
6
|
Condensate pumps
|
7
|
4
|
Vacuum augmenter
|
8
|
4
|
Hotwell tanks
|
9
|
4
|
Feed regulators
|
11
|
4
|
Sea induction valves
|
12
|
8
|
Seawater overboard discharge valves
|
13
|
6
|
Oil Pumps
|
14
|
4
|
Oil Coolers
|
15
|
2
|
Oil Sump Tanks
|
16
|
2
|
Cooling Pumps for oil coolers
|
17
|
2
|
Cooling Pumps for alternator air coolers
|
18
|
2
|
Bilge injections for alternator
compartment
|
19
|
1
|
Bilge injection for motor compartment
|
These valves are “11” and “12” on the diagram,
they are large, and will take some swinging, so we could use a hand. Each
condenser has two pumps, each of 7000m3/hr delivery - quite a lot - so
presumably two are fitted in order to reduce the size of a single unit of
14,000m3/hr, which even today would be too big to fit in an average engineroom.
Even 7000m3/hr requires a lot of space, as shown in the photograph below –
Once the valves are opened, we will go to
the pump starter and start both pumps for each turbine set. At 7000m3/hr and
9.5m head, they consume around 232kW each, but we have plenty of electricity
available and can start other dynamos if we require them. We check the seawater
pressure before and after the condenser to make sure there is no blockage in
the tubes.
This turbine is slightly different in that
it is a two-stage unit, with an HP and LP set of turbine blades to extract the
maximum energy from the steam. The set is very large, as are the auxiliaries
like the condenser and pumps, so to the uninitiated it’s all a bit intimidating
especially with around four dynamos already running with their attendant pumps,
plus the ever-present ventilation noise.
Here’s a sectional view of the propulsion
turbo-alternator
te / ss NORMANDIE, Figure 32 One of 4 Main Seawater Circulating Pumps - copy from The Shipbuilder
On the right are shown the turbine glands
and bearings at the free end, similar to the turbo-dynamos. Above is the large
control valve that operates the turbine. Carrying on to the left can be seen
the turbine cylinder in which there are sets of blading, starting with two sets
of impulse blading (which use the velocity of the steam to do work on the
blades), followed by the rows of reaction blading through which the steam
expands and turns the blades. On exiting from the reaction HP blading, the
steam passes through the large “suitcase handle” bends and into two sets of LP
blading, one fore and one aft, thereby extracting more energy from the steam,
finally exhausting to the condenser through the large opening below the
blading. The condenser is mounted underneath this opening, attached via a
bellows piece to allow for expansion, contraction and vibration between the
units. These are large machines, as shown in the photos below. Note the
“suitcase handle” bends –
Now that we have all the lights on in the
turbine room, everything is bright and pleasant - most unlike other ships of
the era that were gloomy places in which to work. In both pictures you can see
the “suitcase handle” bends between the HP and LP turbine wheels, and in the
bottom picture, the electrical switchboard - this is a starboard outer unit,
and the more observant amongst you will notice that the ladders are not in the
same direction as the plan! Alongside is one of the many switchboards for the
machinery; there’s another one next to the port outboard turbine set.
These are really huge pieces of
engineering, and we are going to start them up in readiness for sailing,
starting with the port outboard set, shown at the top of Figure 32.
1.
|
Again we check that there is a level of
water in the condenser “4” of the first unit - there is a gauge on the side
for this.
|
2.
|
We open the valves on the suction and
discharge side of the condensate pumps “6” and start them up. The water is
pumped from the bottom of the condenser and back in at the top. As the level
is quite low, the pump can be left to its own devices, circulating the
condenser. Once the level starts to rise, the automatic regulator will start
to divide the flow between the condenser and the feed tanks.
|
3.
|
As there are one or more turbo-dynamos
running, we know that the steam is dry and up to temperature in the main
steam lines, ready for us to start warming through the propulsion turbines.
4. Re-set the emergency governor. This
will have been tripped to stop the turbine when it was last used.
|
5.
|
Open all drains (main steam stop valve, turbine cylinder, main steam strainer).
This will ensure there is no water collected in the cold piping as it comes
into contact with the steam from the main lines. Make sure the drains are
clear and steam is issuing out of them.
|
6.
|
Check that the seawater supply to the
condenser is still satisfactory.
|
7.
|
Check that the motor-driven oil pump
starter switch is in “on” position. Start the pumps “13” (there are 6 of
these, two are redundant units) and allow the oil to circulate through the
turbine, gearbox and generator bearings. Once the turbine is up to speed, the
engine-driven LO pump will supply the pressure, and this pump can be set to
“auto”. It is used if there is a trip of the generator in service,
automatically starting to supply lube oil as the turbine runs down to a stop.
There are sight glasses on the bearings where we can see the oil swirling
round them.
|
8.
|
Open cooling seawater valves to the oil
coolers “14” and start the oil cooler seawater cooling pump “16”. The circuit
has a thermostatic valve to maintain the oil temperature as the turbine warms
up.
|
9.
|
Open the valves on the cooling seawater
pump for the alternator air coolers. This will circulate seawater through the
cooling coils in the alternator. Again it has a thermostatic valve to maintain
the temperature of the armature windings.
|
10.
|
Turn gland leak-off 3-way cocks to
engineroom leak-off, and then seal the glands by admitting steam. The glands
are at the ends of the turbine shaft, and if left unsealed, will allow steam
to flood out of the ends of the shaft - not good. They also prevent air being
drawn in under vacuum when the turbine is stopped. A small amount of steam
leakage at this stage will prove that there is no chance of air being drawn
in; we will adjust the gland steam pressure later under running conditions.
|
11.
|
Turn on steam supply to the air ejector
(“vacuum augmenter”) “7” (next to the seawater pumps) secondary jet. This
will start removing non-condensables out of the condenser and improve the
vacuum.
|
12.
|
Turn the engine on the turning gear. This
machine engages with a gear on the turbine shaft, and slowly turns the
turbine to avoid “rotor sag”. It is useful when we are warming through, but
there is an interlock that stops us from allowing the steam control valve to
open. Withdraw the turning gear once the engine is warmed through, otherwise
the control valve won’t open.
|
13.
|
Open the main stop valve slightly to warm
the turbine. This will allow steam to flow slowly into the turbine and start
to warm up the blading and casing. This is important in order to allow the
turbine to expand to its working condition. Too fast and the blades will bind
on the stator - not good. The steam will condense as it passes through the hp
and lp turbines, and run down to the condenser. It will take some time to
warm through such a large machine, and experience tells us when we can go on
to the next step.
|
14.
|
When vacuum has reached 20 inches, we
open the stop valve until the turbine starts to turn, closing it somewhat
immediately afterwards to prevent the turbine gaining speed too rapidly due
to the large rotating masses.
|
15.
|
Gradually speed up, and then keep the
turbine running at about 10% full revolutions (250rev/min) for ten minutes,
then bring it steadily up to 20% of full speed (500rev/min) in not less than
fifteen minutes.
|
16.
|
There are two governors on these
machines, (a) an oil pressure governor, which controls the speed between 7%
and 20%, and (b) a centrifugal governor to control between 20% and 100%. This
means that the speed of the propulsion motors, driven by these alternators,
can be controlled asynchronously by varying the speed of the alternator. We
will discuss this once we are in the propulsion motor room
|
17.
|
At 20% speed the centrifugal governor
will now come into action and take control of the machine from the oil
pressure governor.
|
18.
|
We can now open the stop valve fully, as
the governor will control the engine speed. The machine is now rumbling away
(quite quietly), and we check round all the gauges to make sure all is OK -
oil pressure, hp steam pressure (23.5kg/cm2) and temperature (around 325C),
vacuum (very important), and
all bearing and alternator temperatures. We need to take our time about this,
making absolutely sure everything is functioning correctly.
|
19.
|
As the turbine-driven oil pump is now
supplying the system, we can stop the auxiliary motor-driven oil pump and
switch it to ‘Auto’ control, so that it starts if we get a turbine trip.
Normally we would test the trips at this stage to make sure the control
system works, so will assume that we have done this.
|
20.
|
Vent the condenser of air by opening the
vent cocks at the top, and vent the vacuum pump circulating water spaces.
Check again that the condenser water level is being regulated properly. We
will shortly be starting up the feed heating system instead of returning the
water to the feed tanks when the proper condenser level is reached.
|
21.
|
Turn on steam supply to vacuum ejector
primary jet. Adjust this to give the best vacuum with lowest possible steam
pressure.
|
22.
|
The turbine is now running “straight
condensing” in that the steam is passing through the blading and exhausting
to the condenser, where it is condensed into feed water.
|
23.
|
Shut off the external gland steam supply
and open the valve controlling gland steam leak-off into the turbine to
reduce the leak-off to the engineroom.
|
That’s our first turbine up and running. We
will now make sure the feed system is functioning, after which we will go to
the control station and try controlling the turbine from the manoeuvring
platform. Once we have done this, we will return to the alternator room and
start up the remaining 3 sets in the same way.
7 Propulsion feedwater system
This system is essentially the same as the
turbo-dynamo system explained above. There are no drawings available, so just
the general outline will be explained. Referring to the drawing and tables of
Boiler Room 4 (Figure 19), the feed water is pumped from the feed collection
tanks via the lp heater “U1” by
the Turbo Main Feed Pumps “S1”
(starting these is similar to the other turbine sets, after which they run
continuously) and discharged through the hp heater “V1” before entering the boiler feed piping to the
boiler rooms, from where the feed regulators admit it to the boilers in order
to maintain the levels. The feed system will now regulate itself almost
automatically as a closed circuit system.
Insert a typical feedwater system from
Pentatech
7 Propulsion feedwater
system
This system is essentially
the same as the turbo-dynamo system explained above. There are no schematics available, so just
the general outline will be explained.
From the turbine exhaust,
the steam enters the condenser. This is
a large item of equipment slung underneath the turbine – seen in the picture
below:
te / ss NORMANDIE, Figure 38a Main condenser prior to lifting on board - editpors collection
The tubes and passages of
the condenser induce the best pass of steam around the tubes (through which is
passing the seawater circulating water) in order to condense the steam into the
well at the bottom, as shown in the drawing below:
The water is drawn from
the well by the main condensate pumps “6” shown in the picture, which have a
capacity of some 200m3/hr, drawing under a vacuum and discharging to the
condenser level regulator.
te / ss NORMANDIE, Figure 40a Main condensate pump and condenser level controller - editors collection and copy from The Shuipbuilder
The level regulator has a
float operated valve which responds to changes in the condenser level. Owing to the throughput of these condensers,
the level volume is quite small, the upper and lower levels being shown on the
condenser section drawing at Figure 39 and the float chamber in the drawing
above. As the condenser level rises, the
float acts on the valve, which passes more water to the system. Conversely as the level falls, the float
drops and sends a proportion of the water back to the condenser. This hydraulic type of level regulation is
simple and effective.
Again we duck through the
watertight door into Boiler room 4 and into the feedwater pump flat at the
after end -
Referring to the drawing
and tables of Boiler Room 4 (Figure 19), the feed water is pumped by the Turbo
Main Feed Pumps “S1” from the feed collection tanks to the lp heater “U1” and hp heater “V1” (fed with auxiliary
exhausts and bled steam in the same way as the dynamo feed heaters) before
entering the boiler feed piping to the boiler rooms, from where the feed
regulators admit it to the boilers in order to maintain the levels. We nip up the ladder shown on the right of
Figure 41 to access the feed heaters on the flat above. These will already be on line, but we will
need to open up the bled steam valve from the turbines; we’ll give a Junior
Fourth Engineer that job, so that he keeps an eye on the resultant feed
temperature, which should be 125-130C on the hp heater discharge.
We go back down the ladder
to the feed pump flat, open the pump suction (large) and discharge (smaller)
valves, make sure the selected feed pump exhaust is open to the lp feed heater
and open – slowly – the feed pump control valve, shown top left in Figure
42. The pump starts to spin up to speed,
and we see the discharge pressure gauge, shown top right on the photograph
above, start to move in positive pressure direction. The gauge line from the discharge side of the
pump (on the same stub pipe as the gauge, but independent of it) goes to the
steam inlet control valve governor in the same way as the dynamo feed pumps,
thereby speeding up or slowing down the pump to match the demand; we would
expect the discharge pressure to be in the lower regions as we are using steam
and the boiler levels are dropping, so the pump will be running at almost full
revs. Each of the six main feed pumps
can deliver up to 200m3/hr at 36kg/cm2 discharge pressure, fed with superheated
steam at 23.5kg/cm2 and 325C; you can see why the lagging shown in Figure 41 is
of a thickness to avoid burns on contact.
The pump suction valve is on the larger bore piping, with the discharge
on the smaller bore.
We can now leave this
system in the hands of the Watchkeeping Juniors to keep an eye on it for us.
8 The Manoeuvring Platform and Control Desk
At the after end of the propulsion
alternators is the manoeuvring platform, where the controls for operating the
machinery are centralised. This is an impressive place, and quite unlike other
liners of the period.
As you can see from the photographs, the
area is light and spacious, and separated from the noisy and hot enginerooms.
The photos show the engineers in uniform, which is fine when nothing is going
wrong, but one would think they would wear boiler suits when on watch within
the machinery spaces other than the control desk. Above and to the left can be
seen the main telegraphs which receive the speed commands from the bridge. On
the desk itself can be seen the shaft and alternator revolution indicators
above the reversing and speed control levers (of which more later) and on the
right of the picture, the main control switchgear with the large handwheels
provided for manual working in emergency.
In Figure 44 above is a clearer view of the
two manoeuvring consoles - one for the starboard set, one for the port sets of
turbo-alternator and propulsion motor. The control cabinets show the parameters
from the machinery spaces regarding temperatures and pressures of the various
systems, along with the electrical information gauges.
From the other ships in this series whereby
the turbines are directly connected to the propeller shafting or via a gearbox,
in Normandie there is no connection between the propulsion alternators and the
shafting.
Before we connect the alternators to the
propulsion motors (in the next section), we will run a speed test on the
alternator that we started in the last section.
Standing at the control desk for the
turbo-alternator that we started above, there are two levers. One is the
reversing lever, the other the speed control lever. For this test we are not
going to synchronise the alternators with the motors, as we do not want the
screws to turn at the moment until we have all four alternators running.
8.1 The Reversing Lever and Speed Control Lever
Now for the science bit… Normandie differs
from other transatlantic liners in that the control of the machinery is far
more complicated, though in fact easier to use than a conventional direct or
geared turbine drive. The Control Desk has two main levers on it for reversing
and speed control.
The Reversing
Lever as
its title suggests, is solely concerned with operating the shafts either ahead
or astern. To achieve this, the reversing lever has 7 positions as follows:
(a) Reversing
Lever 7 positions 7
positions
1 Central Position
Stop Stop
3 Ahead
Positions 1 Starting Asynchronously 1
Starting Asynchronously
2
Locking (i.e. as a synchronous motor)
3
Normal Running
3 Astern Positions 1
Starting Asynchronously
2
Locking (i.e. as a synchronous motor)
(b) Speed
Control Lever 5 Positions
1 Central
Position Steady
Speed
On one side of
the central position:
2 positions
“More Speed” 1
more speed increase (fine adjustment)
2 more speed
increase (quick change, or coarse adjustment)
On the other
side of the central position:
2 positions
“More Speed” 1
less speed increase (fine adjustment)
2
less speed increase (quick change, or coarse adjustment)
The Speed Control lever is brought back to
the central position by a spring.
Leaving aside the synchronisation with the
propulsion motors for a while (have patience - everything comes to he who
waits), we will just use the levers to run the propulsion turbines up and down
in speed to check the action of the governor. The turbines themselves do not
reverse, so we will not be using the reversing lever, which only acts on the
propulsion motors.
The Reversing Lever will be at the “Stop”
position, and we will leave it there.
Now we move the Speed Control Lever in the
direction of “more speed” - it doesn’t actually matter whether we use the ahead
or astern positions of this lever, as the turbine will only move in one
direction anyway, and we are not connected to the propulsion motors as
explained above.
On moving the lever, the governor gets a signal
via the electrical system to increase the speed of the turbine set by one
increment in speed, and the turbine revolution indicator will show this
increase. On releasing the lever it will return to the central position with
the revolutions constant at the last set speed. The turbine may be then be
increased in speed up to full speed by small increments,
or -
Move the lever to the second position
“quick change” and the turbine revs show a larger increase in speed, with the
speed being maintained by releasing the lever to spring-return to the central
position. We speed up the turbine to full speed using a combination of small
and large increments in order to test the governor response.
We can hear the increase in speed of the
turbines, and one of us goes back to the turbine room to check round and make
sure everything is functioning correctly. Even though we can see all the
parameters on the gauge board in the Control Room (steam pressure, vacuum,
seawater, lube oil pressures etc.) it is still wise to use the human aspects of
monitoring of sight, sound and hearing, which are not easily replicated with
automation, especially in the 1930s.
Note:
|
Whilst
the turbine is increasing in speed, the amount of steam being condensed in
the condenser will increase, and the level controller (Figure 40) will pump more water from the condenser
into the feed system. In turn, the
boiler feed controllers on each boiler in use will sense the drop in level of
the boiler water and open to admit more water into the boiler to maintain the
correct level. As the controller
opens, the turbo feed pumps will react to the requirement, increase speed and
pump more water through the feed heaters, which in turn will heat the feed to
the set temperature via their thermostatic controllers. On slowing the turbine, the reverse
operations occur, with the water level in the boilers rising, so closing in
the level controller and reducing the amount of water through the feed pumps
and heaters. This is what is known as
a “closed cycle” where reactions to steam demand happen automatically. In the older steamships, none of this was
automatic, and therefore a lot more engineering staff were required to watch
the levels and temperatures in the various items of equipment.
In
modern steamships and motorships, the level of automation is even more
enhanced in order to reduce the manning requirement and therefore operating
costs. On stand-by leaving and
entering port only the watchkeeper and a senior engineer (usually the Chief
Engineer) is required in the engineroom, with only the watchkeeper required
once the ships is full away on passage.
Compare this with the hundreds of sweating firemen and trimmers
required on a coal-burner when underway, and even the number of firemen
required on Normandie. At least the
engineering staff (the officers) of Normandie would be reduced owing to the
amount of automation and ease of operation of this remarkable ship.
|
Now we have tested the speed increase, we
move the lever the other way from the central position and reduce the
revolutions by either small or large increments in order to test the speed
reduction. The feed system will follow us as we reduce speed until no more
reductions are possible and the turbine is back to the speed we set when we
first started it (i.e. 20%, the minimum for manoeuvring).
8.2 Main propulsion motor room
We are nearly at the stage whereby we can
test the main motors ahead and astern. I don’t know about you, but this is
quite exciting after spending all this time down below bringing the monster
alive!
We’ll leave the manoeuvring Platform and
exit through its after door to the upper platform of the main propulsion motor
room…
te / ss NORMANDIE, Figure 45 Main Control Desk - copy from The Shipbuilders
te / ss NORMANDIE, Figure 46 Propulsion Motor Room (lower level) - copy from The Shipbuilders
te / ss NORMANDIE, Figure 46 Propulsion Motor Room (upper level) - copy from The Shipbuilders
The Propulsion
Motors (1) are enormous, and are connected to the shaftline on which are
mounted the propellers which drive the ship. The separation between the turbine
driver and the motors (i.e. without any mechanical connection) means that the
turbines and motors can be placed in more convenient places without having to
line up in any particular way.
te / ss NORMANDIE, Figure 48 A main propulsion motor on the test bed - editors collection
te / ss NORMANDIE, Figure 49 Multi-Collar thrust block (L) and Tilting Pad (R) - collection Stephen Carey
te / ss NORMANDIE, Figure 50 Excitation Groups mounted in the ship - collection Stephen Carey
te / ss NORMANDIE, Figure 51 Manoeuvring Desk for two port side screws - collection Stephen Carey
te / ss NORMANDIE, Figure 52 Water tube boiler section
te / ss NORMANDIE, Figure 53 Section through Boiler Room 4 at Fr 114 - copy from The Shipbuilder
te / ss NORMANDIE, Figure 54 Section through No 3 Boiler room, Fr 206 - copy from The Shipbuilder
te / ss NORMANDIE, le Deesse de la Mer, steaming ahead - colouring courtesy Daryl LeBlanc
te / ss NORMANDIE, le Vaisseau de la Mer - colouring courtesy Daryl LeBlanc
8.2.1 Ref
|
Qty
|
Designation
|
1
|
4
|
Propulsion Motors
|
2
|
5
|
Excitation Groups
|
3
|
2
|
Thrust Blocks
|
4
|
2
|
Intermediate Shaft Bearings
|
Ref
|
Qty
|
Designation
|
5
|
2
|
Turning Gear
|
6
|
2
|
Shaft Brakes
|
7
|
1
|
Switchboard
|
8
|
2
|
Low voltage switchboards
|
9
|
1
|
Desk
|
10
|
6
|
Oil Pumps
|
11
|
4
|
Oil Coolers
|
12
|
4
|
Centrifugal oil purifiers
|
13
|
2
|
Oil reheaters
|
14
|
2
|
Oil Sump Tanks
|
15
|
1
|
Dirty Oil Tank
|
16
|
1
|
Engine Oil Tank
|
17
|
1
|
Paraffin Oil Tank
|
18
|
1
|
Cylinder Oil Tank
|
19
|
1
|
Submersible Bilge Pump
|
20
|
2
|
Auxiliary Switchboards
|
21
|
4
|
Exhaust Fans
|
It’s quite quiet in here at the moment, but
that will soon change. It’s another cavernous space, and the main propulsion
motors are unbelievably huge. Note the man standing on one in this picture of a
motor on the test bed –
The Excitation
Groups (2) comprise five units (4 working, one spare) which serve to
excite the turbo-alternators in order to synchronise them by locking them with
the propulsion motors. These are important, and without them the motors cannot
be driven by the alternators. We will start these up in our next step.
The Thrust
Blocks (3) transfer the thrust of the propellers to the ship’s
structure; otherwise this force would act on the motor itself and tend to push
it through the forward motor room bulkhead! This would of course wreck the
motor, so it’s a very important part of any ship’s shaftline.
Note:
|
In the older
ships of this series such as Titanic, adding ever more small thrust blocks in
a line astern of the engine increased the thrust capability. Needless to say,
as the engine power increased over the years, the length of the thrust
collars and blocks was too long, but in 1905 a fluid-film thrust bearing
patented by Australian engineer George Michell was invented. Michell bearings
contain a number of sector-shaped pads, arranged in a circle around the
shaft, and which are free to pivot. Michell's invention was notably applied
to the thrust blocks of propeller driven ships. Their small size (one-tenth
the size of old bearing designs), low friction and long life enabled the development
of more powerful engines and propellers. Hydrodynamic lubrication was the
key, whereby the tilting of the pad formed an oil wedge which itself took the
thrust rather than the pad. As the load increases, the oil wedge viscosity
increases and therefore the load still transmits through it without the
thrust collar coming into contact with the tilting pads.
|
The Intermediate
Shaft Bearings (4) or “Plummer Blocks” support the shafting along its
length to stop it sagging or whipping. They are lubricated on the “splash”
system whereby a collar picks up the oil from a bath and tips it over the
bearings.
The Turning
Gear (5) is used to turn the engines to make sure they are free. A motor
driven cogwheel engages in the motor shaft and turns the engine and shafting.
Before starting this turning gear is removed to avoid damage if the engine is
started with it engaged. An interlock is provided to ensure this, but all
marine engineers are wary of the interlock malfunctioning.
The Shaft
Brakes (6) are used to bring the shafts to a quick stop prior to
manoeuvring astern or to stop windmilling (the ship driving the propellers as
opposed to vice versa). Once
the controls are set to stop or astern, the shaft brake will engage to stop the
shaft before the astern power is applied.
The Switchboards
(7,8 & 20) handle the control switchgear, the Desk (9) is for writing up the
engineroom log.
The Oil
Pumps and Oil Coolers (10&11)
supply the oil system that lubricates the motor bearings and cools the return
oil via a closed system.
The Centrifugal
Oil Purifiers (12) are provided to purify any water or sediment out of
the lube oil on a continuous basis, to avoid corrosion and wear of the bearing
surfaces. The purifier bowl spins at many thousands of rev/min to spin the dirt
and water to the outside of the bowl, where it is removed by automatic
“desludging” on a modern ship, but probably manually on Normandie.
The Oil
Tanks (14-18) are for the storage of various lubricants which we will
not go into here.
The Bilge
Pump (19), like the others in the machinery and boiler rooms, is
provided to pump oil and water out of the bilge spaces in the motor room.
The Exhaust
Fans (21) expel used air from the spaces, with fresh air being either
drawn in or delivered via ventilation fans.
8.2.2 The Double Excitation Controllers
In order to synchronise the alternators
with the motors, thereby allowing propulsion to take place, the alternators and
motors have to be excited in order to transmit the power between them. Without
exciting the motor stator, no drive current will be induced in the salient
poles of the rotor. In other words we are going to apply current to the stator
in order to induce the motor rotor to rotate, in the same way as a normal
electric motor.
The controllers are duplicated, for port
and starboard side screws. The actual making and breaking of the circuit
contactors is carried out automatically from the control desk, as the powers
involved are considerable. Even so, large handwheels are provided on the front
of the control boards in the event of an emergency such as failure of the
remote control.
Each controller is operated by an electric
motor within the control desk (or the emergency handwheels above), and has the
following four positions:
Notch 0 Stop (this was the position used when
testing the alternator governors above)
Notch 1 Starting of propulsion motor
asynchronously
Notch 2 Locking (electrically) as a synchronous
motor
Notch 3 Normal running
We will start the ventilation and exhaust
fans to ventilate the space prior to starting, then start the oil pumps and
open the valves for seawater for the oil coolers for the propulsion motor that
twins with the alternator we started earlier - i.e. the Port Outer unit. We
check that the oil pressure and circulation is satisfactory.
8.2.3 Double
Excitation Motor groups
These units as mentioned above serve one
alternator-motor group each, with one spare. The motor has a generator mounted
on each end, one for the motor excitation, and the other for the alternator
excitation.
In the photograph (Fehler! Verweisquelle konnte nicht gefunden werden.) you can see
the motor in the centre, with the excitation generators rigid-mounted fore and
aft on the same shaft. We go to the excitation motor starters and start all
four as we are going to be using the other three after testing the port outer
set.
To start the propelling machinery, we go
back to the manoeuvring console and - at the controls of the port outer sets - bring
up the alternator speed via the speed controller (see section 8.1 above) from
20% to about 25% speed (i.e. 2,430/4=607rev/min). We then have to excite the
alternator, which allows the propulsion motor to start asynchronously. To do
this we go back to the controller and move the lever to Notch 1, which will
start the propulsion motor at its synchronous speed (about 25% or
243/4=60rev/min on the shaft). Once the shaft is turning at this speed, we move
the lever to Notch 2, which excites the motor windings and locks the alternator
and motor together as one unit. We now move the lever to Notch 3, which is
“Normal Running”. Ready to go…
We can now test the propulsion motor ahead
and astern using the reversing and speed control levers on the manoeuvring desk
as follows, but first we contact the bridge (hopefully someone is up there by
now) and ask if it is clear to rotate the screws ahead and astern. With such a
powerful ship, it would not do if the lines were only singled up, as the
propulsion effect of only low revolutions could strain the moorings. In
addition there may be small boats about which would suffer if they were in the
vicinity of the propellers. Safety first, even in 1935…
Having received the go ahead, we already
have the reversing lever at “Normal ahead (Notch 3)” position. Moving the speed
control lever from the central point to position “1” for a small increase in
speed, the alternator revs increase, and - gratifyingly - so does the propulsion
motor on this shaft, as evidenced by the revolution indicators on the control
desk; you can see the two indicators side by side on the control desk for the
two port-side screws.
The two revolution indicators for the
alternator and motor are shown in front of the two levers for each unit. The
outer levers are the Reversing Levers, the inner are the Speed Control.
It’s important to remember that the motors
when locked electrically together, will speed up and slow down in direct
relationship to the speed of the turbo-alternator.
That has successfully tested the ahead
rotation, now for astern:
We reduce the speed to 25% on the
alternator, then move the reversing lever to “Stop” - Notch 0. This will de-energise
the excitation, the alternator and motor will unlock, and the shaft brake will
be applied. We now move the reversing lever to the position astern, Notch 1.
The motor will start to turn with a powerful starting torque in the astern
direction (note that the alternator only runs in one direction and does not
itself go astern) due to over-excitation of the alternator.
There is a light on the ammeter which dims
as the motor takes the current, but once this current is absorbed, the light
becomes bright again and we move the reversing lever to Notch 2 astern, locking
electrically as an asynchronous motor. When locking is attained, we put the
reversing lever to Notch 3 astern whereby the motor continues to turn as an
asynchronous motor, whilst the excitation of the alternator is reduced to its
normal value. We can now increment the speed by moving the speed control lever
to “more speed” (probably marked “Plus
de vitesse” in actuality) and watch as the alternator and motor
revolutions increase together. Moving the speed lever to “less speed” (“Moins de vitesse” anybody?) the
revolutions drop back to the original speed and we can move the reversing lever
to “Stop” thereby decoupling the motor and alternator and applying the shaft
brake.
Well, that was exiting, wasn’t it? To be
able to get on board and start things up and eventually turn the screws of this
great liner is quite an achievement!
9 Getting underway - standby
Having started and tested one
alternator-motor set, it only remains to fire all the boilers required for full
power at sea, and to start the remaining three alternator-motor sets and test
them in the same way as we did with the outboard set. In reality we would have
started all the alternators together and then tested all the shafts, but we
only did one for the sake of clarity. Assuming that the other three shafts have
been tested and proved satisfactory, we can call the bridge, test the
telegraphs and steering gear, synchronise bridge/engineroom clocks and report
that the engineroom is ready for sea service.
By this time, all the required engineers
and firemen will have clattered down below and will be at their stations in the
boiler and enginerooms. Everything is double checked, and when we walk from
forward to aft now, there is an intense roar in each boiler room, and it’s
getting quite warm. The firemen are tending the fires and making sure the
boiler water levels are maintained. In the dynamo/alternator and motor rooms,
all the engines are running and it’s quite noisy now with 4 or 5 turbo-dynamo
sets running and all four propulsion alternators. Coupled with the noise of the
supply and exhaust fans, if ear defenders had been de rigeur in those days, it would probably be wise to wear them.
Your job as an engineer office for this
watch is at the engine controls - confident? You should be, as you have gone
through the ship and started up all the required items of machinery in order,
and know how to drive the screws at whatever speed and direction is required
via the telegraphs.
When the lines are singled up, the Master
will ring “Stand-by” (Etre prêt seems
a reasonable translation into French, but is more probably just Attention) on the telegraphs to warn
the engineers that movements are expected. One of the Junior Engineers reports
this in the “Movement Book”. If you have read the previous ships in this
series, you would be on “steam spinning” now to avoid the turbine rotors from
sagging and to maintain an equal temperature throughout the machines. With
Normandie there is no need to do this as the turbines are running continuously,
and the motor shafts will not sag or distort due to temperature - another task
eliminated…
The bells ring! Dead Slow Ahead (if anyone
can supply the telegraph markings in French, that would enhance this story - Google
can’t help, it seems). The Junior records this and the time in the Movement
Book and you move the reversing lever to Notch 1 Ahead, wait a few seconds for
excitation, move to Notch 2 to lock asynchronously, then to Notch 3. Move the
speed control to “More speed” and release the lever, whence the shaft
revolutions will increase. Not quite fast enough, so we’ll give her a little
more on the “More Speed” until we match the revolutions for Dead Slow Ahead.
The telegraph rings again - “Stop”! (Arrêtez! - Google has that one). You
move the reversing lever to “Stop”, the alternator and motor uncouple and the
shaft brake is applied.
“Slow Astern” rings on the telegraph, the
Junior assiduously enters it in the Movement Book, you move the reversing lever
to Notch 1 astern, then Notch 2, then Notch 3, and give the speed control lever
a jag towards level 2 - quick change. The speed increases to above Dead Slow
Astern, and with practice you know whether to apply larger or smaller movements
of the speed lever in order to reach the desired revs as soon as possible. This
is too easy…
Movements like this will continue as the
ship leaves the berth, the engine movements aiding the tugs as she leaves
harbour. Once the tugs are cast off, the bridge will tell the engineroom, which
means that it’s unlikely there will be any more major manoeuvres. The ship will
likely stay on Stand By whilst leaving the English Channel (La Manche - I knew that one!) and
once clear of Ushant the bridge will ring “Full Away on Passage” usually by a
movement of the telegraph from Full Ahead to Half Ahead and back again, plus a
call from the bridge to ask for the fuel consumption figures for stand by. The
Junior enters “FAOP” in the Movement Book along with the time, and his job
there is done. You on the controls gradually ease the ship up to “full sea
revolutions” (sounds good, doesn’t it?), whilst the other engineers “check
round the job” - in French - before leaving the engineroom until their watch
below. At the end of your watch, the next Watchkeeping Officer, who has done
rounds of the machinery spaces on his way down, relieves you if he’s happy with
the state of “the job”, and you can go up top after a job well done. The life
at sea as a marine engineer is a rewarding one…
Note:
|
You may be wondering
about the Junior Engineer and his Movement Book. This important book records
all the engine and bridge telegraph movements during manoeuvring, and both
the engineroom and bridge copies should correspond. In the event of an
accident, the Movement Books are one of the documents that would be required
in an Enquiry, and if they don’t tally, or are altered in any way, something
fishy has gone on. For this reason, any alterations are to be crossed out,
signed, and the proper order written underneath - no” Snow Pig” allowed
either - and no spaces are allowed between movements. The bridge and
engineroom clocks are synchronised at Stand By for this reason. Nowadays
there are bridge voice and telegraph “black boxes” similar to those carried
on aircraft, but the good old Movement Book stood the test of time for
centuries
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10 Other items of interest
10.1 Scotch Boilers
Now that we have got the ship underway for
America, we can have a look at the Scotch Boilers (B) in Boiler Room 3 (see
Figure 17: Boiler Room 3 - Plan, and Figure 18: Boiler Room 3 - Elevation).
Whilst we started one of the main boilers,
it is also possible to fire the Scotch Boilers at their reduced pressure of
10kg/cm2 in order to warm through the lines and raise sufficient steam for the
steam-heated oil fuel units supplied for the main boilers. We missed out this
step for the sake of clarity and to avoid confusion - we had enough to do…
The designers of the vessel considered that
it was risky to rely on the evaporators for producing boiler water in view of
the reliability of the equipment. As the steam to make fresh water from
seawater has to go through tubes with seawater pumped around them, any pinhole
leak in the copper coils could under certain circumstances lead to seawater
getting into the feed water. The effect on boilers - especially watertube - can
be catastrophic, so the Scotch boilers - which are firetube type -were provided
as they are not so susceptible to water impurities. These boilers supply steam
to the air extractors (vacuum augmenters, or vacuum ejectors - there are
several names for this equipment), the turbine steam-jackets and the feedwater
heaters. The steam used in this way is discharged to the condensers and goes to
make up the losses in the main feed circuit. The condensate from the domestic
water heaters is also led to the condensers after having passed through one of
the main heaters.
If the quantity of water so introduced is
too great, the overflow of the main tanks automatically discharges into the
tanks for the Scotch boilers. The auxiliaries fed with steam from the Scotch
boilers do not call for high pressure, and hence these boilers have been
designed for the moderate pressure of 10kg/cm2, which enabled their weight to
be kept down. This low pressure installation also comprises an auxiliary
condenser and distilling plant, which will be brought into service when the
water is found to be unsuitable for feeding direct to the Scotch boilers or
when fresh water is not available. In that event, the distillers will be fed with
seawater.
10.2 The Boilers
10.2.1 Main Boilers
The main watertube boilers were
manufactured by the Penhöet Yard and are of the three-drum type, with
superheating to 350C at 28kg/cm2 pressure.
10.2.2 Scotch Boilers
The 4 Scotch boilers in Boiler room 3
supply steam at 10kg/cm2 saturated.
Le NORMANDIE
ss
NORMANDIE 1935-1942 VIII
ss NORMANDIE 1935-1942 IX
ss NORMANDIE 1935-1942 X
Digitization of NORMANDIE
ss NORMANDIE 1935-1942 IX
ss NORMANDIE 1935-1942 X
Digitization of NORMANDIE
Starting from Cold Series
Starting
rms EMPRESS OF BRITAIN from cold
Thanks a lot for this article which is a real treasure for an engineer fan of the Normandie like me. To help you for the translation of telegraph orders; Normandie had four telegraphs on the bridge (one per shaft), with 9 orders on each one:
ReplyDelete-at the center: "STOP" (...for stop :-))
-then four orders ahead ("AVANT"); from the center position:
-"LENTEMENT" (for "slow ahead"), most of the time in french this order was given saying "(EN) AVANT LENTE" but maybe on Normandie was it by saying "(EN) AVANT LENTEMENT"? I don't know... (the difference between the two words is lentement=slowly; lente=slow)
-"DEMIE" (half ahead)
-"TOUTE" (full ahead), saying probably "(EN) AVANT TOUTE"
-"ROUTE LIBRE" (full away on passage)
-four orders astern ("ARRIERE"); from the center position:
-"MANOEUVRE TERMINEE" (finished with engines)
-"LENTEMENT" (slow astern), saying "(EN) ARRIERE LENTE" or "(EN) ARRIERE LENTEMENT"
-"DEMIE"
-"TOUTE"
Hope it helps you.
Regards,
Guillaume
Merci Guillaume
DeleteHello,
ReplyDeleteI was wondering if you could send me a full set of the Normandie deck plans from the Shipbuilder. If you have the full copy if the Shipbuilder scanned in I would appreciate that too. Please reply by email to wmclapper@gmail.com
Winston