At present our country has considerable number of medium-sized and small coal mines,in its production process material or coal transportation uses single drum winding winch.

 
  • 我國目前存在著(zhù)相當數量的中小煤礦,其生產(chǎn)過(guò)程中的物質(zhì)或者煤炭運輸多采用單滾筒纏繞式絞車(chē)。
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