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Handling of the tubs during the actual loading and unloading of the cages was a labour intensive process but subsequent movement between the shaft-side and the tipplers at the screens required little intervention.
At the North pit-top the top-deck tubs were unloaded slightly higher than the tipplers and were allowed to gravitate to them whilst the bottom deck tubs gravitated to a creeper chain which raised them up to the tippler. After tippling, top deck tubs were raised by a short creeper chain before gravitating back to the shaft side, whilst bottom deck tubs gravitated back directly.
Following the 1950s modernisation, the tubs were replaced by large 3 ton mine-cars and their loading/unloading and movement was mechanised and automated as much as possible.
At the South pit, only three men were required for the entire operation - the loading point operator, the onsetter and the banksman.
At the North pit, however, the underground loading point was some distance from the pit-bottom and mine-car movement required the use of battery locomotives and a larger number of men underground.
Both pit-top and pit-bottom decking operations were pneumatically powered. Powerful compressors were in continuous operation supplying air at 100lb/sq-in to large receiver tanks. Air was piped from the tanks to the shaft-sides where it was distributed to the rams and catches by pneumatic control systems using interconnected shuttle valves. The decking operation was under direct manual control of the onsetter and banksman, but all other mine-car handling was done automatically via pneumatic logic.
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