roof support pattern

矿业英语词汇-专业词汇-... ... roof support 顶板支护 roof support pattern 顶板支护布置方式 roof survey plug 顶板上的测桩 ...

矿业工程... ... roof support 椤舵澘鏀姢 roof support pattern 椤舵澘鏀姢甯幂疆鏂瑰纺 roof survey plug 椤舵澘涓婄殑娴嬫々 ...