| 出生地 |
Jiangsu China (Mainland) |
| 牌子的名字 |
chenlong |
| 类型 |
钻头领 |
| 机器型号 |
钻探工具 |
| 验证 |
研究所 |
| 材料 |
高锰铁 |
| 使用 |
钻井 |
Elevator groove and slip groove made on the box thread face of normal drill collar or sprial drill collar can be used as lifting sub and safty slip when trip out. The technical parameters for elevator groove and slip groove is as per API Spec.7-1. Hard banding is optional at customers request.