This page is to provide an overview for cleaners and firemen of the technical details required to perform their tasks on the WD without embarrassment!
Locomotive Background
The locomotive affectionately known as the DubDee was built in 1943 by North British in Glasgow, for the Hellenic State Railways. It was withdrawn in 1979 and returned to the UK in 1984, acquiring number 90775. It has worked on the NNR since 2003 and was named 'Royal Norfolk Regiment' in 2017.
The locomotive was designed by Robert Riddles as one of the series of 'Austerity' locomotives for the War Department. It weighs 78 tonnes, with a 55 tonne tender carrying 9 tonnes of coal and 5000 gallons of water.
Notes for Cleaners
The loco has a rocking grate and hopper ashpan similar to BR Standard locomotives operated from inside the cab. Unlike BR Standards, it is perfectly possible to drop the pan from the cab - so concentrate when you are stabled and rocking the grate - you don't want to operate the hopper doors unless you are over the ash pit.
As the loco has a wide grate extending over the frames, ashing out is done from ground level through two doors and the dampers:
There is a long door on either side of the ashpan, below the boiler foundation ring, held closed by bolts - open these to wash the ash into the pan. You may need a rake as the ash compacts at the back of the pan, and the hopper door is near the front.
Fireman's Controls
The fireman's controls are traditional in their layout - Riddles' later BR Standard layouts are not used here, other than the coupled water gauge valves.
The main steam manifold valve is the black lever above the regulator, with the blue rag on it.
The injector water valves are awkwardly placed. This is the driver's side injector water valve, and it is right under the driver's seat. It it closed in this picture - rotate it 90° anticlockwise to open it:
Forward of that valve is the lever for the cylinder cocks. The fireman's side injector water valve is similarly under the fireman's seat. The tender has two valves used to isolate the tender tank from the locomotive:
You can use the right hand one in the picture to operate the water supply to the driver's side injector, and leave the valve under the driver's seat open all the time.
Adjacent to the fireman's seat are the auxiliary tools operated from the fireman's side injector:
The WD has small damper flaps towards the rear of the ashpan, on either side. Pulling these levers up closes them:
Lighting Up
The firebox on this loco does not breathe well when cold, and laying a thick bed of coal will result in the fire choking and taking a very long time to warm up - it may need assistance from an artificial blower.
The locomotive's own blower will not work well below 40 psi., and the fire will produce a lot of soot from the firehole until it is going well. The answer is to lay the fire with plenty of air space on the grate, or lay two fires, one on either side until the fire is going well and creating it's own draft.
Firing the WD
The best way to fire this loco is to build a really deep back end, so high that it's up to the door. This gives a big energy reserve, much like you use the deep front on the B12. You keep the front and sides covered to keep the foundation ring warm and you allow holes to form in the middle if you want to control the heat. Watch for holes, as they tend to form on the edges, cooling the foundation ring - partly because the shape of the baffle plate makes the area halfway down the side of the box the most difficult to reach.The pressure needs to stay above 160 psi, and preferably between 200 and 220 psi but it is easy to fire with a longish shovel as long as your shovel is cranked enough to get coal in the back corners and you are reasonably good at firing left handed. The loco blows off at 225 psi, though the loco seems to be quite tolerant of pushing the red line - it feathers for a while and is easy to recover. Maybe it doesn't have the pop safety valves of the later BR Standards.
When you are building the fire ready for the next run, top up the front and back, fill in the sides and when you want to make steam quickly, fill the middle in. To get the pressure high enough for a really good run up the hill, put some extra coal across the front.
Currently the WD has a relatively long flame scoop and firing the front corners is not easy for the inexperienced.
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