The defects will be found in the seam side with ultrasonic inspection but hardly found with X ray inspection as the small diameter spiral pipe production with the split strip steel.

采用纵剪带钢生产小口径螺旋焊管时，超声波检验经常在焊缝的一侧发现缺陷波，而X射线拍片检验却很难发现。

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Officially, the move is to eliminate duplication--since both the exchange and its watchdog now split this inspection function.

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