列炮局 OD Cannons opening

列车炮 railway gun ; railroad gun

斗列炮 Opposite Direction Cannon

两行交错排列炮眼 [矿业] staggered blastholes

BX系列炮孔成缝剂 BX series blasthole splitting agent

端点放炮排列 end-on spread ; end-on ; offend spread

扇形炮眼排列方式 ring pattern

炮孔排列法 drilling pattern

辐射形炮眼排列方式 radial drilling pattern

人工中间放炮排列 artificial split spread