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The third and final winder at the South pit was manufactured by Markhams of Chesterfield and installed in 1922. In August 1920 a considerable number of tenders for the new winder had been received, but the ones which were liked the best were from Markhams and Thornwill & Warham, the latter being “substantially stronger in all points” than the former. It was agreed that the “stronger tender” was worth an extra £2000 although exactly what the difference was is unknown.
Endeavours were made to get a firm quote from Thornwill and Warham, but this does not seem to have been forthcoming and after Markhams gave a firm price at the begining of October the contract was awarded to them.
The initial Markham design proposal, drafted on 13th September 1920, was based upon a winder installed in 1913 for the Butterly Coal and Iron Co. at their new colliery at Ollerton. It had two 36in by 84in horizontal cylinders fitted with double-beat drop valves. The 20ft by 11ft 6in timber-lagged drum was serviced by a steam brake-engine operating two pairs of post brakes onto Vee’d brake rims. A Whitmore overwind device was employed.
A number of changes were made to the proposed design, however. It had the same engine-layout but with the controls now on the right-hand side. The drum was replaced by a 21ft by 10ft one with steel plate lagging, scrolled at the outer coils to overcome problems with the relatively wide fleet angle at Pleasley due to the proximity of the headgear sheaves and the potential depth of wind to the Blackshale seam. A pair of powerful, under-slung Burn’s type brakes, operating onto Vee’d rims were substituted for the smaller post brakes and a Thornwill & Warham ‘profile’ overwind device, driven from the depth indicator shaft was fitted in place of the more out-of-date chain driven Whitmore unit.
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