Counterweight

A single conveyor counterweight at Wangi Power Station hangs from a heavy chain inside one of the coal-conveyor bays, the cast-iron block suspended above a steel pulley. The counterweight is about the size and shape of a small filing cabinet, the cast iron rusted to a uniform reddish-brown across its surface. The chain that suspends it runs up through a steel guide frame to an anchor point overhead. The pulley below is the return wheel for the conveyor belt; the belt itself has been removed. The bay around the counterweight is steel-framed, the floor concrete, the walls clad in corrugated steel sheet. Daylight comes through a small window high in the cladding.

Counterweights provided the tensioning force that kept the conveyor belts at Wangi running at the right speed and tension. Each belt drove a return loop around a pulley pair, with the counterweight pulling against one of the return pulleys to take up slack. Wangi's coal conveyors ran from the receival yard up to the boiler bunkers above the firing levels, moving coal continuously through every operating shift across the working life of the plant from 1958 to the closure of B Station on 31 October 1986. The belts came out for salvage; the counterweights stayed.