Delorimier Shops of the Canadian Pacific Railway
Rolling stock and steam locomotives 1850 to 1900
General characteristics and maintenance challenges
How the Canadian Pacific Railway kept them rolling
From an old postcard :
In Sherbrooke, Quebec, at the "CPR station", on some unknown date ...
you can observe the technology at this bustling transportation hub.
At the left an electric streetcar, then horses with carriages and wagons,
and a typical railway locomotive and passenger equipment from the late 1800s.
It looks as if the railway equipment is being switched.
Many railway lines meet here ...
so equipment is probably coming from, or going to, different railway lines.
The "Standard Locomotive" 1850-1900
Below, is a nice phantom view of the standard locomotive of this era.
Water and wood enter the cylindrical boiler and the square firebox below it ... at the left side of the image.
Smoke and steam travel to the right of the image ... following separate paths along the boiler cylinder.
Metered doses of steam move a single piston on each side of the locomotive in sequence.
The pistons push and pull driving rods to turn the large driving wheels.
On the "steam exhaust phases" of piston movement,
spent steam moves vertically from each cylinder ...
into the hollow smokebox (which forms the front of the locomotive) ...
and continues vertically out the smoke stack.
Using Bernoulli's Principle, this vertical blast of spent steam sucks combustion gases from left to right ...
along the length of the locomotive boiler interior through flue pipes ...
and sucks oxygen-rich air into the firebox for efficient burning.
In other words, waste piston steam provides a draft for the fire.
This particular design of locomotive was
successful in North America - performing most of the work between 1850
and 1900. Some have suggested that this arrangement of having a light
front end, with a little swivelling pilot wheel "truck" to guide the
curves ... and a heavy back end with the firebox and most of the boiler
sitting over the driving wheels ... was the most perfectly balanced
locomotive ever created. Or, maybe they were just being kind of wistful
for the smell of wood smoke and tallow lubricant when they were saying
Most of the locomotive structural frame rests on the axles attached to
the large driving wheels. The main part of the frame provides support
for the cab, the firebox, and the large amount of water that jackets
the firebox ... and the firebox's network of flue tubes which run
within the cylindrical boiler to a point just to the left of the
Look again at this main frame sitting over the driving axles. A
necessary innovation of this era, was the system of springs and
equalizers. They ensure the driving wheels follow the contours of the rough pioneer railway
track ... almost like the independent suspension for each wheel on an
If the driving wheels were not kept in constant firm contact with the rails:
- They might slip, causing the locomotive to momentarily lose
traction and buck against the momentum of the train ... breaking link and pin
couplers and possibly derailing the train.
on a curve, a driving wheel turning but momentarily not in contact with
the rail, might climb up and over the rail, derailing the locomotive.
Innovation without standards
The earliest engine-eers were actually professional engineers or
those with a
similar aptitude for invention, innovation and practical metal bashing.
At first there were no standard
locomotive blueprints, railway equipment specifications, or government
regulations for guidance. On their own, the inventors had to discover
which bigger, better design might just waste fuel, hammer the track to bits,
shake itself to pieces, derail too frequently, explode, or just sit there
hissing. The inventors had to learn quickly.
What was it really like during the dot-steam boom ?
As the railways started in Canada in 1836, it was like a whole word run
by beta software ... you know the type.
The earliest locomotives were Macs; 4.77
mHz PCs; TRS-80s; Commodore (Vanderbilt) 64s; etc.
After 100 years of government regulation to protect workers and the general public, it is hard to picture the railways of 1850.
So here's a picture to help ...
On a US railroad, these ornate, circa 1850 passenger coaches show why government regulation of railways was necessary.
Without resistance to "buff" (longitudinal) forces, a collision or
headend derailment often caused wooden passenger cars to "telescope".
(In this late 1880s accident, 64 people died)
The earliest coaches were wooden shacks, on wooden beam frames, rolling along on iron & steel 4-wheeled trucks (wheelsets).
They were heated by wood or coal stoves.
Had that overturned stove been in use, there wouldn't be much wreckage for us to inspect.
Notice how light the rail is too !
Supporting a coast to coast railway
CPR in the East, 1885
On this map, you can see the extent of
the CPR and all the lines it owned
and/or leased for 999 years
and/or operated in eastern Canada as the last
spike was being driven. Back then, everyone was into mergers and
acquisitions. The CPR "grew by acquisition" in the east. The story
of its "growing by the spikemaul" west of Callander, Ontario ... [pause for effect, deep voice] ... is
... Canadian ... legend.
What usually gets less attention is how this cobbled-together and scratch-built system actually functioned.
Here are a few ideas:
- As you have seen, railway cars were mainly made of wood and the
"barriers to entry" for the railway car construction industry were low
just needed wood, skilled carpenters, and a big shed for them to work
in ... and a few specialized iron or steel castings or fabrications to
bolt on or plunk underneath.
As the CPR railway system was developing, our "standard locomotive" above was being built by :
Baldwin Locomotive Works, Philadelphia
Canadian Engine and Machinery Company, Kingston, Ontario
Danforth Locomotive and Machine Company, Patterson, New Jersey
The Hinkley & Williams Works, Boston
The Portland Company, Portland, Maine
Rhode Island Locomotive Works, Providence ... Rhode Island
- For most of its first few decades, the CPR was always short of locomotives and bought from a number of different suppliers - sometimes waiting in line for deliveries.
- Over the years, companies in Scotland, England and Germany, sometimes built "American-style" locomotives to CPR specifications.
So, 1850-1900 there was NO convenient local "dealer service" for locomotives :
The valve gear, pistons, driving rods and other "drive train" precision parts weren't readily interchangeable between all these locomotive brands.
Fortunately, sheet metal and bars, rivets, pipes, cast wheels, axles and bearings made up much of the locomotive,
and with well-equipped shops with powerful cranes,
specialized railway employees could repair, rebuild and manufacture these elements.
Auxiliary appliances (headlights, whistles, bells, etc.) and gauges were often interchangeable and could be switched or bought by the case.
The specifics of this generalization are infinitely debatable
among the members of the Loyal Order of Rivet Counters.
But my point ...
for the other people who have no
Canadian railway history inspired tattoos
from different acquired railways
from different builders
with inherited and/or newly recruited maintenance forces
in small, geographically scattered locomotive shops
would not have been easy for the early CPR.
To survive, the CPR needed to
1. Develop an efficient system to keep its rolling stock (locomotives AND cars) rolling.
2. Standardize its rolling stock over time to make future maintenance more efficient.
The CPR needed to use standardized :
spare parts ...
efficient procedures ...
worker training and skills ...
to provide ...
increased reliability of its equipment ...
which was spread all across the Canadian wilderness.
Common railfan tattoos: Sydney 4 - 8. 5 Semper Fer
CPR organizes its maintenance
These days, some old Canadian military helicopters require 30 person-hours of work for each hour flying. I don't know what the ratio of maintenance hours : operation
hours was for early steam locomotives. However, the model for daily
steam locomotive maintenance was closer to the helicopters' ... than to
a domestic automobile or even a modern high mileage highway truck. As a
result, roundhouses were maintained every 125 miles or so to ... remove
ashes ; wash out boilers ; fix minor steam leaks and other mechanical
defects ; lubricate, repack or replace bearings ; refill tenders ;
clean ... on and on.
But when the boiler was due for rebuilding ; the "power train" and
suspension were worn down ; a frame was cracked ; system upgrades were
Big stuff required a big "back shop" full of parts, with a big crane.
Before 1885, contractor rolling stock and CPR revenue-producing rolling stock
west of Lake Superior (often originally delivered by rail via US lines) ...
was isolated from CPR' s eastern shops. This was because the
difficult area north of Lake Superior was the site of the "second to last, Last Spike".
In the longer term, it would not have made sense to haul a dead damaged locomotive 2000-3000
miles for major repairs in Montreal. So shops with significant capacity
were being built in Winnipeg. But with the opportunity to pinch pennies in
person not far from the headquarters in Montreal ... you can bet that the
CPR would retain its greatest repair capacity in Montreal for about a
At the very beginning, CPR used the following acquired shops for its heavier work :
Canada Central Railway ... Locomotive shops at Carleton Place, Ontario ; Car shops at Perth, Ontario
Quebec Montreal Ottawa & Occidental ... a roundhouse and small shop at Hochelaga
To take you back to the general environment, here is a postcard view :
Here is the Grand Trunk (west) end of Montreal Harbour.
The Grand Trunk
Railway (eastbound from Toronto - today the CNR)
ran along the southwest edge of Montreal Island ...
it then crossed the Victoria Bridge to the south
shore of the St. Lawrence,
and continued to the port of Riviere du Loup - close to the mouth of
the St. Lawrence.
I guess that this view is from 1900 or a little later.
There are no comedy festivals, roller bladers, or busking mimes to be seen back then at the "Old Montreal" waterfront.
At the right lower corner, you can see a boxcar which has been taken off its trucks, serving as a wooden shed.
There is an island, downstream from us, near the right horizon ...
Imaginatively named Ile Ronde is just offshore from the CPR Hochelaga Shop at the CPR (east) end of Montreal Harbour.
Delorimier Shops layout
The Carleton Place locomotive shops were nice and central on the CPR
system. Parts of the old stone railway complex still exist today.
However, the CPR needed a much greater rebuild and repair capacity for
its rolling stock. So it built its "New Shops" near the waterfront at
Montreal, just west of its Hochelaga facility.
Other advantages of this spot :
Below is an circa 1890 plan of some of the shop features. Not all of
the railway lines are shown. The compass rose at the right top corner
displays north to the "5 o'clock direction". The St. Lawrence River is just
beyond the left edge of the image. A railway car builder in Ontario used
prisoners to provide labour for its shop. I have wondered if the parcel
of land was just handy, or if the CPR was considering inmate labour from the "Montreal Jail" at
- Many railway supply companies were located in Montreal so funny parts were handy or could be quickly obtained.
- Imported heavy machine tools, and rolling stock equipment could be brought in conveniently by ship.
- Montreal had the capacity to provide a steady supply of skilled and/or cheap labour - depending on the demands of the work.
to Headquarters. The CPR still had financial challenges and some
administrators liked to "help" the work along as much as possible.
The "New Shops" ... more properly The Delorimier Shops
(because they were on a street named Avenue de Lorimier - and I will
explain that) ... were connected to the CPR mainline by August 1883.
These plans are from a city atlas, and the technique for updating seems to have been a cut and paste process ... with real
scissors and glue. That's why some of shop track leads don't line up.
As you conclude from the plans, locomotive overhauls and building from scratch, and
heavy freight car and passenger car work, could be done here. Hochelaga and
other shops on the line handled most of the simpler car work.
I have concluded that the engine house had a covered turntable (under the half octagon) so snow would not have to be shovelled out of the turntable pit in winter.
The transfer table probably operated from the track stub near the paint shop ... up to the top of the white column with the letters ("SHO") as in WORSHOPS (?!)
A transfer table is a long rectangular "tray" on which track has been
laid - like they use on a turntable. A car or locomotive for shopping
rolls onto the tray. But while a turntable spins around, a transfer
table carries the rolling stock in a direction perpendicular to its normal direction of travel.
When the rolling stock is lined up for the appropriate servicing door,
they roll the rolling stock in off the tray. On a relatively small
parcel of land like this, transfer tables make the best possible use of
So at Delorimier, a single transfer table operating along that vertical white column, keeping rolling stock parallel to the yard tracks,
could deliver the rolling stock to, or between :
- the erecting shop building,
- the car shop,
- the paint shop.
A look inside Delorimier
Above, you can see a photograph of the
interior of the locomotive shop. For scale, there are 5-6 foot locomotive
driving wheels in the centre. A locomotive boiler can be seen at the
left edge of the photo.
An interesting hoist is in the foreground. With a guideway above and a
metal rail to roll on, I wonder if the crane uses electricity from a
A fascinating aspect of this shop is that the machine tools are driven
by belts coming from a central rotating shaft at the upper left. A
central steam plant would keep the shaft spinning. While air or
electricity driven tools would be safer than having all those belts
whirring around where people were working ... I'm guessing that air and electric tools
weren't readily available, affordable, or "proven" to the satisfaction
of the railway bosses at this point. So until that day comes, keep your shirts tucked in, fellas.
Two Solitudes ... again
Delorimier Shops were on Avenue de Lorimier ...
but on the plan, it is Colborne Avenue?
John Colborne, First Baron Seaton (1778-1863) ... was a widely experienced British career soldier (Waterloo, etc.) ... who applied his knowledge to the
administration of British colonies when peace came. On his retirement
in his 80s, he was promoted to the highest rank in the military, that
of Field Marshal.
Francois-Marie-Thomas Lorimier, (called 'Chevalier de' Lorimier - but born in Canada after the French Revolution) born 1803, Saint-Cuthbert, Lower Canada. A
notary who participated in the Patriote Rebellions for responsible
government and local control of tax monies ... among other issues.
Previously, the Patriote Party had held a majority in the elected Lower
Canada Assembly ... which had little legislative power.
Colborne was an able
military leader who personally took command of the troops at the Battle
of Saint-Eustache during the first rebellion in late 1837. Nearly 100 Patriotes
were killed ... first as they fired from the town's church and other stone
buildings ... and later as they fled these buildings which the troops had
set on fire. Lorimier, acting as a Patriote militia officer, had fled Colborne's
guns and bayonets when things seemed hopeless. An idealist with Liberty
Fever, Lorimier abandoned his family and practice in Montreal,
regrouped with other Patriotes in Vermont, and participated in
uprisings again the next winter.
After his imprisonment and trial by British court-martial in 1839 for being a Patriote leader,
Lorimier's wife appealed to Colborne to spare her husband's life. Colborne did not respond to her letter. Lorimier was among 12 Patriotes hanged for their part in the rebellions.
Colborne was a reasonable
administrator and better than most of the duds Whitehall sent over
(including Lord Durham, with his two warring bosoms, or whatever) at
practical challenges of ruling British North America. However, he was
foremost a guardian of the successful British system of government ...
thinking too far beyond orthodox Victorian thought was not a policy
option when it came to people convicted of high treason.
from Saint-Timothee (where Lorimier was active during the 1838 rebellion - "Patriotes, Part Doo" - around Beauharnois), one David Gagnon,
was among 58 Patriotes shipped off to Tasmania for six years before
successful appeals had them all pardoned by Queen Victoria. A public
subscription was organized to pay for their passage back - as the return trip was
'not included' in the original 5 month long Tasmanian 'Devil May Care' Penal Colony Cruise. The original
intention had been to keep them there for life.
Before the pardons - as the losses and punishments from the Rebellion
became entwined in the Canadien identity - the evocative lyrics of Un Canadien errant were written and applied to a traditional folk song. Un Canadien errant
became a Canadien anthem for the the absent Patriotes who were exiled
far away from their native land. Over time, it was sung as a "chanson a
repondre" all over North America as Canadiens travelled to remote areas to find work.
Of the mainly American-born rebels who simultaneously rose up in Upper
Canada over most of the same issues ... none was executed
slightly larger quantity was bundled off to Australia. The British
authorities were savvy enough not to start hanging ex-American-Upper
Canadians ... with the massive population of the new republic so close
and so sympathetic to fighting for democracy.
The British administrators of the Upper & Lower Colonies probably figured that no one would notice that the
Lower Canadians received harsher treatment 170 years later, eh?
Of course they
were right ... only the Quebec school system ; museums - general or with
a Patriote specialty ; and a recent controversial film about Lorimier's
last 24 hours ... preserve this
In "rep-by-pop" post-Confederation Canada - in 1883, 44 years after his execution - Lorimier's widow and two
daughters were found to be living in poverty. A collection of $1000 was
taken up by private citizens and given to her as compensation. Montreal city council renamed the street from Colborne to Delorimier in 1883 as well.
Lorimier's incarceration and hanging had taken place at the jail shown adjacent to the CPR shops in the plan above.
So in this website's typical fashion, I have taken you to Tasmania and back - to explain a Montreal street name.
Rolling stock: wood and labour
From 1900, here an illustration showing the official specifications for
the ladders, roofwalks, grabirons and hand brake rigging for a standard
wooden boxcar. As you know, before train air brakes were operated by
the engineer, the brakemen would run from car to car, along the
roofwalks, stopping at each hand brake wheel to wind on the brakes.
Into the 1950s, roofwalks were maintained on freight cars.
The illustration below, shows how you
take a wooden shack on wheels (an early boxcar) and protect its
contents from rain and snow. This was back in the days when labour and
wood were cheap. In addition to the special asphalt roofing, and
multiple layers, the roof would be kept well-painted. The diagram even
specifies the orientation of the wood grain to help shed the water.
To keep all its boxcars maintained, the CPR needed car shops.
Below is an old "arch bar" truck. This
name distinguished it from newer "cast trucks" which feature
solid castings ... rather than the assembly of curved metal bars bolted
together which you see here ... forming the truck's side frame.
Cutting, bending, and bolting standard metal bars together was "state of
the art" when the CPR began its operations. Purchasing,
constructing, storing, assembling, replacing, repairing, adjusting and scrapping all
these parts as they wore out, demanded a good system of
procurement and stores, skilled workers, supervision, and a system to co-ordinate
regular repair and renewal of freight cars.
Please memorize the names of the 47 labelled items for the exam.
While wood was fine to begin with, steel
construction became necessary as loads became heavier and locomotive
pulling power increased. Steel could also be bent into funny shapes if
you required it. Coal cars such as this (also known as "hopper" cars because of
the "funnels" in the bottom through which the contents emptied by gravity) were
required in great numbers because coal was the fuel which powered
industry ... and the railways. At the mine tipple, coal would come
crashing down into the car body and steel was certainly more durable that wooden boards to
take that kind of punishment.
As our rolling stock illustrations
become more complex and impressive, take a look at the complexity of
the cars in which humans were riding by 1900. This was an
illustration showing features of different types of
passenger cars, so there is extra variety in its parts. However, it is
still more complex than the previous box and hopper cars.
Up in the clerestory, you can see gas lighting appliances and the
valves to control the flow of gas. A stove; a car-length signal cord;
three connecting hoses for airbrakes, the communicating signal, steam
heat (the latter if you don't chose the stove for your car) are
visible if you stare at
this long enough ... and just about everything else is made out of
wood. Let's go with the safer steam heat !
The Iron Horse
The Boiler - Pressure vessel
But the most challenging item to design, build and maintain at the CPR's Delorimier Shops in Montreal was a steam locomotive.
The pressure vessel holds steam under pressure at about 10 atmospheres
of pressure. Where the vessel is round and uniform, there are few weak
The flue tubes provide structural strength to the "ends of the can",
preventing the ends from being blown off. However, notice that the area
under pressure between the top of the
firebox and the top of the boiler
is strongly reinforced with
staybolts. These steel rods were carefully located and very securely
fastened at each end to strengthen geometrically weak areas which were
subject to irregular pressure
stresses. Another reason for this complicated arrangement of staybolts
at the firebox ... was the fact that firebox contained coal burning at
about 2000 degrees F ... with lots of uneven expansion as the
locomotive reached operating temperature, and the reverse as it cooled.
- The left third is the firebox,
with a diagonal brick arch to cause the coal gases (including heat-rich
methane) to swirl and around and burn completely and efficiently.
- The middle third has most of the water surrounding the flue tubes (pipes) which took the hot waste gases to the right for expulsion.
- At the right third, the smoke box,
the hot gases exit the flue tubes ... and linger for a split second
... before waste steam from the cylinders blasts them out the stack.
The dome at the top is the
"steam dome" where a "dry pipe" (not shown) - above water level - would take
the high pressure steam down to the cylinders to do work. The steam dome is
directly above the hottest part of the firebox with the thinnest
covering of water.
The Smokebox - Playing the Pan Pipes of Hell
We are looking into a locomotive with its "front" taken off. The compartment revealed is called the smokebox. Here at the smokebox,
ALL the boiler's high pressure steam (at 10-12 atmospheres pressure) is
safely away from us inside the boiler or steam pipes. (However, you
would never fire up a locomotive in this state)
- The two big grey curved pipes carry high pressure steam
downward. The engineer has put this this steam in motion by opening the
throttle valve to a specific position (like using a lever faucet in the kitchen today).
- The steam then flows out through those big black pipes at 45 degree angles into the "little black circles" ... the steam valves.
- The steam valves use various mechanical "tricks" (you'll see !) ... to meter the desired amount of steam into the partially hidden "big black circles" ... the cylinders ... which contain the pistons.
- The high pressure steam moves the pistons to propel the locomotive ... again the valves do all the magic.
- The waste steam from each piston is released, via the valves again, to
the centre of that big black "saddle" casting below the grey smokebox area.
While all this is happening, sulphurous
coal smoke is coming at us from a honeycomb of flue pipes - many of which can be seen in the bottom
third of the smokebox.
Then taking roughly one second, and in strict sequence :
... then the valve on the other side releases waste steam, and the same sequence is repeated.
- The valve on one side releases pressurized waste steam from its corresponding cylinder below.
- The steam goes to an area of lower pressure (the saddle casting below the smokebox).
- The next area of lower pressure is the smokebox so the steam rushes there.
- The area of lowest pressure is "the atmosphere". This is reached through the circular hole in the top of the smokebox - the smoke stack.
- On its way through the smoke box, the blast of steam sucks the
coal smoke from the flue pipes - as if the steam is playing the
Pan Pipes of Hell (sort of).
When a steam locomotive is travelling at high speed, these alternating exhaust
blasts are faster than a fast jackhammer breaking up concrete.
Missing from this illustration are things like a "petticoat pipe" which
help to direct the waste steam's flow through the smoke box and out the
21st Century Financial Journalism, Creative Writing Assignment : Ode to Steam Locomotion
This "one second journey" of the steam
(from valve to stack) is what gives the steam locomotive its dramatic,
lifelike sound - unmatched by other types of motive power.
The sound is so captivating and unique that business reporters (almost HALF A CENTURY after the demise of steam) still remark that
"Canadian Pacific Railway has 'chugged' its way to another year of profit".
Valve Gear - Managing expanding steam efficiently
If you like puzzles, you'll LOVE figuring out the pocket watch logic of these diagrams. Please explain them to me when you get them figured out.
Three relatively simple things are happening in the diagrams below.
Steam at full pressure is coming down the pipe (that "black 45 degree
angle pipe" above) and entering the chamber around the centre of the
"spool". The spool is actually our friend the magic valve. You can see
all the little ingenious chambers and channels which its movement - left and
right - gives the high pressure steam access to. (To avoid insanity,
simply repeat after me: "The steam always moves from high pressure to low pressure ... this is not rocket science!" ... uh ... actually a sectioned liquid-fueled rocket diagram is much easier to understand.
- Steam is being reduced in pressure from about 10 atmospheres to
about 1+ atmosphere ... the lost steam power is being turned into useful work.
- Pistons are moving in and out, but the connected driving wheels are going round and round.
- Clever mechanical design engineers ... and conscientious
locomotive engineers (i.e. drivers) ... are getting the most power
possible out of the steam's energy.
Below the valve "spool", is the cylinder containing the piston. The
piston is more like a stick with a circle on its end. Again, lots of
special shaping, chambers, and channels are involved.
While you would intuitively assume the steam only does work when it pushes the piston
to the LEFT ... you can also see by studying this puzzle that the
piston also does work as it travels to the RIGHT. Being an external combustion engine (no fuel is burning IN the
cylinder) steam engines needed all the efficiency they could get ! Thank
you steam locomotive design engineers ... after whom with affection the eccentric crank is probably named.
The next part is sort of "chicken or
the egg". Keep in mind there is a similar set of equipment on the other
side of the locomotive. The driving wheels are permanently pressed onto
the axles which connect them ... so the locomotive's LEFT wheels'
permanently locked to RIGHT wheels' rotation ... but the LEFT and RIGHT
side rods and valve gear are NEVER
in an identical position at any time. Everything has been carefully
designed so that somewhere, somehow, all the mechanical parts will instantly provide full power when the throttle valve is opened.
The locomotive (driving) engineer doesn't care where the left side/right side wheels, rods, valves, and pistons are positioned
when he opens the throttle. All he knows is that steam will flow through through his open throttle, pass through "the
valves" and push "the pistons" ... one way or the other on both sides ... then the
train moves ... and he starts getting paid.
However, the locomotive engineer cares very much about the position of his "reverser" lever before he cracks the throttle.
Back to sitemap
If you care : the reverser changes the relative positions of "radius rod" and the "link".
Using the reverser, the engineer determines:
- Which way the wheels will
turn : he doesn't want to actuate the bell to announce imminent motion
... signal FORWARD motion with two whistle toots ... and then BACK his
locomotive into his train!
- That enough steam is being sent to the cylinders to start and accelerate a heavy train ... but that steam is not being wasted
when less work is required. The latter point matters to him as railways
such as the CPR regularly post a list of engineers' use of resources ...
particularly fuel !
The reverser affects ... valves and
valve gear on both sides of the locomotive ... controlling both
direction, and steam "cutoff" (quantity and timing) for each piston
reverser's control of "cutoff" is effectively like selecting a manual
overdrive on an automobile ... same speed, less fuel (steam = fuel).
"Name three types of valve gear !"
... Rolly would always smile and demand this when we visited. I would
remember Stephenson (for historical reasons) Walschaerts (from Trains
Magazine) and always forget Baker. This gave Rolly the opportunity to
remind me and we both relived the days of steam. My shocking lack of essential knowledge
confirmed, he would then continue to another favourite question about the weight of
rail used on the original CPR ...
The valve gear shown above in Fig. 4 is Walschaerts ... including an
essential little addition which Fig 3 is missing. In reality, the main
driving wheel (at the left) would share its power with the other two
wheels through a passive connecting rod for better traction. It gets sooo
Walschaerts Valve Gear was invented by ... Egide Walschaerts, a
Belgian, in 1844. There were many, many different types of valve gear
invented over the years and some were more popular than others.
Stephenson, named for the most memorable pioneer of the first steam
locomotives on the first steam Rail Ways, was the valve gear used on early simple locomotives like the
"standard" locomotive model at the beginning of this page.
Once railways got into bigger power in North America after 1900, sixty year old Walschaerts valve gear (and the similar Baker valve gear) got the nod.
Similarly, might we be using circa 1990 9-pin dot matrix inked-ribbon printers with our computers in 2050 ??
These are the types of things which design engineers thought about ... Walschaerts was ...
- Relatively lightweight.
- All the gear is outside of the frames and wheels ... for easy lubrication, inspection and repair of all the moving parts.
- With the axle and frame (the inside area) clear of gear, more internal bracing could be added for greater locomotive structural strength.
- The parts which wore out were mainly "pins" which connected the rods to the wheels. Not a big deal.
- Being light, the gear inflicted less uneven wear on the valves.
Old Stephenson, New Stephenson
Development during the first 50 years
In the same year that railways began in Canada and the Patriotes were becoming restive ... here is one of
Stephenson's locomotives. More or less sectioned on the median plane
(or "cut in half by a buzz saw") this view shows the inner workings of a
typical Stephenson locomotive. Considering maintenance and "big power"
... the cylinder and valve gear are between the wheels and under the
boiler where you don't have many options. However, between 1836, 1883
(CPR Delorimier Shops) and 1900 (Walschaerts valve gear becomes popular) the
basic Stephenson valve gear got bigger and better.
By now, you'll able to spot the following parts on the Stephenson engine :
- Steam dome and dry pipe (to get the steam from the top of the boiler)
- Throttle and main steam pipe
- Flue tubes
- Cylinder and piston
- Smokebox and stack
- Bonus question : spot the safety valve
- To become a lucky qualifier for a draw for 100 bonus points ... explain the valve gear
Below is the first locomotive constructed at Delorimier Shops, built November 1883.
It has Stephenson valve gear and nice clean lines. It is sitting on the Delorimier Shops transfer table.
It was rebuilt by CPR Angus shops in 1908 and scrapped in 1920 (lifespan: 37 years).
Delorimier Fades Away
After 21 years of operation 1883-1904, Delorimier was replaced by the Canadian Pacific Railway's Angus Shops.
In 1900, it was becoming clear that Delorimier couldn't keep up with demand.
Since the railway's east-west completion in 1885, vast areas of the Prairies had been settled,
increasing the demand for passenger and particularly agricultural freight transportation.
The growth in Canadian commerce, population, and increasing competition from other railways
demanded bigger and better rolling stock ... and the railway's capacity grew.
Railway equipment is heavy, often complex, and has a long lifespan.
Reliable in-house construction, maintenance, repair, and rebuilding to include efficient new technologies,
enabled the CPR to maximize its use of this expensive asset.
In contrast to engine 285 above ...
Below is one of the last steam locomotives built at Delorimier Shops, November 1902.
It was rebuilt at the CPR Angus Shops in 1920 and scrapped in early 1939 (lifespan: 37 years).
Fun features: The valve gear is outside and the veteran hogger has crossed the cab to pose in the gangway.
The location on the back of the photo is McAdam, New Brunswick, May 24 1934.