UP

Technical | Winders | Pipework  >  Exhaust

Section under development

Contents:

 

In the early 1900s there were four exhaust stacks, two for each winder.  Three of these were located at the sides of the South engine house - probably still in their original position from when both engines were towards that end.  The fourth was positioned at the end of the South engine-house and appears to have stood  away from the wall.

exhausts from SW 1919 -s

West and South exhaust stacks circa 1910 (FoPP/JST)

end exhaust from S 1919 -s

South exhaust stack circa 1910 (FoPP/JST)

exhausts from SE 1919 -s

East exhaust stacks circa 1910 (FoPP/JST)

Prior to 1922, two turbine sets were operated, one a mixed-pressure Bellis and Morcam and the other a Willans and Robinson exhaust turbine - the latter being installed around 1911. These turbines would have required considerable re-engineering of the exhaust pipe-work but how this was configured is not known.

When the Markham winder was installed in 1922 the internal exhaust system was completely re-engineered and this appears to have remained largely unaltered until closure.  Around 1923, a new power-house with a larger mixed-pressure turbine was  constructed requiring further modifications to the external exhaust pipe-work.

The exhausts from each cylinder on the two winders are brought into a large main located below floor level in the central transept and which exited via the west wall.  The exhausts from the South winder combine before joining the main, but those from the North winder are connected individually.  The pipe-work for each connection to the main incorporates a large gate valve which allowed isolation for maintenance or repair.

The exhaust main was connected to 4 Lancashire boilers acting as receivers and supplying the turbine generators. These receivers are believed to have been located in the boiler house on the west side of the South engine-house.  Excess exhaust pressure was passed into  a boiler feed-water heater before venting to atmosphere. At the moment it’s not clear where the final venting took place -  possibly at the inner exhaust stack on the corner of the South engine-house.

Although the majority of the exhaust pipe-work is cast iron and was installed in 1922, there is a section below the North winder where a much earlier fabricated iron pipe has been modified to create an offset. All parts of this pipe, the flanges, joins and seams, are riveted. The two exhausts stacks also contain early fabricated sections whilst at the base of the inner stack there is a seat-bend which looks to have formed part of the early exhaust system.

When the generators were discontinued in the early 1960s, a second stack, connected directly to the exhaust main via an improvised connection was installed alongside the earlier one at the South engine-house.

This second stack is fed from a Hopkinson “Silent Exhaust Valve” tee’d off the main.  The original function of this valve is something of a mystery,  This type of valve was usually fitted between turbines and their condensers and was designed to protect the turbine by venting its exhaust to atmosphere, should the condenser loose its vacuum.  Why it was installed on the winder exhaust main is a puzzle. 

It’s possible that the valve was used to act as a relief valve allowing the exhaust receiver pressure to be slightly above atmospheric, with any excess steam being discharged into the feed-water heater. This would have increased the back-pressure on the winding engines and would have reduced their efficiency slightly, but they may well still have been operating with sufficient capacity.

TOP


Copyright © 2005 - 2017      J.S. Thatcher

Page updated on:

08 Apr, 2018

at

02:15:14 PM

In case of problems contact:

webmaster@pleasley-colliery.org.uk

BuiltWithNOF