Derrick crown block (Offshore Oil Rig and Platform)
The crown block that caps a derrick: a short lattice bay carrying a five sheave cluster on its shaft between two support beams, a grated crown platform and a blank obstruction light. The sheave cluster turns.
- 格式
- GLB
- 文件大小
- 87 KB
- 三角面
- 2,156
- 许可
- CC0 1.0