ERW pipe weld surface

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High-frequency electric resistance welding (ERW) steel pipe production, internal weld surface treatments are generally incomplete curettage (left weld reinforcement) and complete curettage (scraping will form the inner surface of the groove) in two ways, and the results were not ideal, will affect the overall performance of the steel pipe. Taking into account the thickness of ERW pipe welds, strength and reliability of ultrasonic testing, squeeze through thick welds - calibrating processing, optimized contour shape welds to improve the overall performance of ERW pipe.

ERW steel pipe after welding, excess metal is extruded from the weld area, both inside and outside surfaces of pipe burr formation, commonly known glitches, usually scraper to remove internal and external burrs. In actual production, better quality generally scrape the outer burr, but scraping issues within the burrs are more likely to leave some of the inner surface of the glitches over the formation of a high or scraping slot. If within the weld burr handled properly, it will affect the overall quality of the steel pipe.

Under normal circumstances, there are two methods about the scrape ERW pipe weld burr, namely, incomplete and complete curettage curettage.
Incomplete curettage method, which retain a certain degree of inner burr (as some specification allowable burr height not greater than 0.8mm). This method does not hurt the blade base material, does not substantially reduce the structural strength of the weld, but this approach in the subsequent ultrasonic testing of the weld seam, the edges due to residual burrs formed on the base material to form a reflection of the ultrasonic flaw detection for testing the reliability of cause interference, resulting in higher rates of false positives.

Complete curettage method, is about inner burr completely cleaned, the transition between the base metal and the weld area so gentle, eliminating the residual effects of glitches in the subsequent ultrasonic flaw detection. However, this approach often due to work within the system glitch scrape enough stability, such as the presence of vibration, resulting in localized appear scraping groove weld, causing injuries to the base metal, weld parts of wall thinning, structural strength.