| 摘要 |
A first tubular member including a first tubular body having a first pin end and a first bell end opposite the first pin end, a second tubular member with a second tubular body having a second pin end and a second bell end opposite the second pin end, a third tubular member having a third tubular body having at least one third pin end, and a fourth tubular member comprising a fourth tubular body comprising at least one third bell end.
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