After welded pipes are treated by reducing tension mills known as "welded pipe seamless process". There are still some differences between welded pipe and seamless pipe in quality index.

焊管经张力减径机处理后有人称之为“焊管无缝化”，这种焊管与无缝钢管在一些质量指标上仍存在差异。

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Discharge Pipe: Seamless steel, supported at the pump support plate and furnished with an expansion fitting at the casing connection to prevent strain on the pump.

排水管：无缝钢，在泵支撑板处支撑，在外壳连接处配有膨胀部件，以防止作用在泵上的张力。

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The Luxembourg-based company said that results in the third quarter were affected by a lower level of sales of seamless pipe products and higher production costs.

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Companies that supply the drillers were also among the buys, including seamless pipe maker Tenaris S.A. (nyse: TS - news - people ).

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Luxembourg-based Tenaris sells seamless steel pipe products to oil and gas companies.

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