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| верхний шаровой клапан ведущей штанги (imemine) | |||
| верхний клапан ведущей трубы (a valve installed above the kelly that can be closed manually to protect the rotary hose from high pressure that may exist in the drill stem. paderin) | |||
| upper kelly cock: 2 短语, 2 学科 |
| 库页岛 | 1 |
| 萨哈林岛 | 1 |