The Canadian Navy of Yesterday & Today 


This is a collection of photos of the No.2 boiler and engine rooms taken on board HMCS SACKVILLE in 2002 and 2005, supplemented with a few photos taken on board the Ernest Lapointe in 2006. This section of the website is still in DRAFT. Please provide comments, corrections, anecdotes, and/or equipment identifications to the author at smcclearn@hazegray.org.


General layout of machinery spaces in a Flower class corvette (actually ex-HMCS SUDBURY after conversion to a salvage tug - image courtesy of Seaspan International Ltd.). The 1939-1940 construction program Flower class corvettes were fitted with two Scotch Marine "fire-tube" boilers., as shown here. According to Corvettes of the Royal Canadian Navy, these boilers "...held the water inside the huge drum of the boiler and the "fire" was shot through it in tubes which started in the three fireboxes at the bottom and then snaked back and forth through the drum."

The large volume of water contained in these boilers provided a large reserve of steam for hunting submarines, but meant that the boilers were slow to raise steam from a cold start. In addition, the Scotch Marine boilers turned out to be relatively unreliable, and their size limited the supply of fuel that could be carried.

The 1940-41 construction program ships received "water-tube" boilers instead, in which "...the main body of the boiler acted as a firebox and water passed through it in banks of tubes". These boilers were superior in most respects to the Scotch Marine boilers that they replaced, and later allowed for more fuel to be carried thus extending the range of the 1941-42 construction program onward.

The boilers provided steam to a four-cylinder triple expansion steam engine generating 2,750 horsepower, and providing a top speed of 16 knots..

SACKVILLE herself had her #1 boiler removed during the war, a fact that contributed to her survival into present day, as it provided space for cable stores when she was converted into a controlled loop layer after the war.
No.2 Boiler
Boiler 1
No.2 boiler room from above - looking down on the front of No.2 boiler.
Boiler 2
Looking to port. In the centre of the photo is the forced air fan for combustion. To the left of the photo is the starboard firebox of #2 boiler, one of three in the boiler.
Boiler 3
Looking to starboard, with the boiler feed pump in the background.
Boiler 4
Looking to starboard, exit ladder leads out of boiler room. The boiler room bilge pump is in the foreground.
Boiler 5
Front of No.2 boiler, showing the centre firebox.

Starboard side.

Pipe leading to starboard ventilator.

Mounted on forward bulkhead adjacent to exist ladder.

Starboard side. Fuel oil pump.

Fuel manifold on boiler front.

Looking up exit ladder towards trunking to funnel.

Looking forward to starboard in the space above No.2 boiler, with trunking to funnel in the background.

Space above No.2 boiler, forward port corner. Shows current heating boiler 7 - 20 psi operation.

Space above No.2 boiler, looking aft on port side through hatch to engine room. The equipment to the left of the photo is part of the hydraulic package that is used to turn the main engine for display purposes. This turns the crankshaft, which in turn moves the connecting rods and pistons. This equipment is not original, and has only been installed since SACKVILLE became a museum.

Ladder over No.2 boiler.
One of two similar Scotch boilers installed in the Ernest Lapointe at the Maritime Museum of Quebec, showing all three fireboxes.
A side view of a forced air fan similar to the one in Photo #3 above, also taken on board the Ernest Lapointe.
Engine Room

Looking forward in engine room, with hatch to space above No.2 boiler on port side. Lifting beam runs fore and aft through engine room over the engine.

Looking forward in engine room. The curved piping seen here is the "Aiton" bend in the main steam (supply) line from the the main engine to the boiler that allowed for expansion in the line and prevented stressing at the engine and steam throttle valve.

Looking aft to starboard side in engine room. The grey part in the middle of the photo is the top of main engine showing the pressure relief valves and upper valve rod guides (the red objects). The large diameter light grey pipe a the bottom right of the photo is the exhaust steam line leading back to the condenser, which is immediately to port of the main engine, but is just out of sight to the bottom of this photo.

Looking aft and up in engine room. Port holes in deck head visible.

Diesel generator on starboard side of engine room, with ventilation pipe to left. Radiator is to the left of the genset, with the insulated exhaust leaving through the top centre of the photo.

Connecting rod between piston rod above and crankshaft below at forward end of engine. The copper line running down the connecting rod is a lube line.

Looking aft along starboard side of engine, with connecting rods in background. Shows reversing engine (the reversing engine is a steam reciprocating engine utilizing a pinion and gearwheel (rack) to swing the Stevenson Link gear to reverse direction of rotation of the main engine), and also the handwheel for the throttle valve. Also shows the pinion and gearwheel (top of photo). A rod from the gearwheel moves a lever on a longitudinalbeam which moves all link gear as one.

Forward connecting rods looking from starboard to port.

Looking aft above crankshaft.

Connecting rod attached to crank shaft.

Engine room telegraph on starboard side of engine room.

Looking aft along starboard side. Shows the reversing engine. Also handwheel for throttle valve.


Aft end of engine room, looking aft and port.

Three way pump for evaporator set (feed water, brine, and distillate).

Looking forward along starboard side of engine room.

Electrical distribution panel at aft end of engine room.

Looking aft and up to deck head in engine room.

Starboard side, with ship's hull visible to right of shot. This is the base of the engine room feed pump.

Looking aft along starboard side.

Port side, looking aft. Salt water service or bilge pumps.

Shows the actuating arm that swings to move the link gear.


Three way pump again.

Starboard side, looking forward and to port.

Forward bulkhead.

Starboard side, looking forward and up bulkhead.

Starboard side, looking forward along catwalk to bulkhead. Main steam chest and throttle valve.

A view of the main engine pistons removed for display on the port side of the engine room.

Starboard side, looking aft. In the foreground is the main steam isolation valve, at the bottom of the "Aiton" bend.

Starboard side, looking aft with ventilation piping visible.

Looking aft along the port side. The light grey exhaust steam pipe exits the main engine and enters the condenser (bottom centre). The condenser is cooled by sea water, and condenses the steam from the engine to return it to the boiler to be reused.

Looking down onto the condenser, forward along the port side. The condenser is at the bottom centre of the photo, and a pipe leaves the condenser to return water to the boiler via some feed pumps, a feed-water heater, and a deaerating tank.
Looking aft along the port side, with the condenser to the left.
Looking forward along the port side with the condenser to the bottom right.


Macpherson, Ken and Milner, Marc. (1993). Corvettes of the Royal Canadian Navy 1939-1945. Vanwell Publishing Ltd. St. Catherines, Ont.

Correspondence with Ian Urquhart (November 2006).
Correspondence with Neil Goodwill (November 2006).
Correspondence with Keith Allen (November 2006).

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