safety pillar的意思|示意
保安矿柱
safety pillar相关短语
1、 shaft safety pillar 井筒保安矿柱
2、 a safety pillar 保安煤矿柱
3、 coal safety pillar 保护煤柱
4、 safety pillar against sand 防砂煤柱
5、 safety pillar against water 防水煤柱
6、 water-proofing safety pillar 防水煤岩柱
7、 safety pillar under water body 防水煤岩柱
8、 set safety pillar prevent sand 防砂煤柱留设