Zebedee Overhaul Update
After more than two years out of traffic, our flagship locomotive Zebedee's overhaul is well underway. Operations Manager Ben brings you up to date.
Its a common sight on railways accross the country that every ten years, steam locomotives have to have a boiler overhaul where the boiler is lifted out of the frames of the engine to be stripped apart, inspected, have components replaced and re-assembled. This is commonly the time that lots of other work takes place to dismantle the rest of the locomotive and repair / replace any components.
After being in storage for almost 2 years, in late July Zebedee left the railway by road to head off a few miles up the road to Sam Henwood Engineering.
The strip down began in earnest with the cab and tanks being removed, closely followed by the boiler lagging sheets and lagging (these are the painted metal sheets that clad the boiler and the coat of insulation in between the sheet and the boiler itself).
Following this the boiler was lifted out of the frames and the task of assessing the work required to return it to service was undertaken in conjunction with our boiler inspector (steam pressure vessels, such as boilers are subject to independant inspection by a qualified person, this is the boiler inspector) and a plan was agreed. Some of the work will include new boiler tubes, new washout plugs, new gauge fittings and renewed studs for the main steam pipe that carries the steam from the regulator valve to the cylinders (the regulator is the valve that controls the amount of steam that goes from the boiler to the cylinders, a bit like an accelerator in a car).
Meanwhile below the frames, the tyres (much like a car, some railway locomotives have tyres, which is a metal outer ring with the wheel profile on it which attaches to the wheel itself) are having fitted bolts made to replace the generic lock nuts and bolts presently on them. All new wheel bearings will be fitted to the locomotive. The Crank weights have all had new crank pins and were checked for wear.
The valve gear has been stripped apart and re pinnned to make it tight again, as have the coupling rods and connecting rods been pinned and made tight.
The frames themselves have been stripped and cleaned and been put into primer and are shortly going to have new dual height couplings fitted before being put into top coat.
And that largely brings us up to date with whats been going on. There is still a large amount of work to be undertaken but we hope to have Zebedee back in steam and working for summer 2023.
