crown block
短語詞組
- bailer crown -block 撈砂天車
- sliding crown -block 可平移的天車
- crown n block 天車
- g crown -block 可平移的天車
- straight rotary crown -block 單層天車
- run into crown -block 碰天車
- bailer r crown -block 撈砂天車
- valve -against-overwinding crown-block protector 天車卷閘防碰安裝
- arch crown block 拱頂石 返回 crown block