drop weight落锤
drop wagon母仔车
drop vlave engine带配汽阀蒸汽机
drop valve gear坠阀装置
drop valve落阀,落座配汽阀
drop tracery下错窗
drop the business放弃交易
drop testing machine冲击试验机
drop test抛掷法试验,电压降试验,锤击试验,落锤试验,降落伞投下试验,降压试验
drop tank副油箱
drop stone (钟乳状方解石)滴石
drop stamping落锤锻造,热冲压
drop stamp落锤
drop stage升降舞台
drop spillway跌水式溢洪道
drop sorter降落式选材装置
drop siding互搭板
drop shutter test坠落试验
drop shop锻工车间
drop shipper出口中间商,向厂商直接进货的零售商