Transverse cracks and its detection methods

1. The transverse cracks of the thick-walled LSAW steel pipe

Respectively with a thickness of 20~50mm for D36, D36-Z35 and S355 structural steel, producing by molding JCOE pipe platform with LSAW steel pipe with a diameter of 508~1372mm. X-shaped groove weld, for three-wire submerged arc welding inside and outside for multi-pass welding wire submerged arc three. 24h or 48h after completion of welding, do the ultrasonic testing on the weld.

2. Ultrasonic Testing Method of weld defects-transverse cracks of LSAW steel pipe

Transverse crack is with greater dangers than other defects, it is also more difficult than ultrasound testing, which is mainly due to the difficulty to determine the defects nature of the ultrasonic detection. In order to improve the detection rate of transverse cracks, and accurately determine the transverse cracks, combined with standard AWS D1.1 / D1.1M and API RP 2X, etc., summed up the ultrasonic scanning mode transverse cracks. Practice has proved that these methods thick transverse weld crack detection and determination are effective.

2.1 oblique parallel with weld reinforcement scanning

2.2 parallel without weld reinforcement scanning

2.3 pairs of probes across the weld cross scanning

2.4 parallel with weld reinforcement scanning