The petroleum and chemical industries need thousands of tons of steel pipe every year. Among them, welded pipe occupies an appropriate share. Thanks to technological advances, steel bar manufacturing, rolling, welding, seamless pipes can successfully pass through welded pipes? Owing to the cost advantage, ERW steel pipe will be more and more used in green engineering of petroleum and chemical industry.


In recent years, the trend of replacing high-cost seamless steel pipe with high-quality welded pipe has emerged in the world. This is mainly due to the continuous breakthroughs in the production technology of welded pipe, which is reflected in the following aspects:
(1) The progress of desulfurization technology reduces the sulfur content of steel and improves the welding quality of steel pipe.
(2) The application of vacuum degassing technology improves the purity of billet, reduces inclusions and improves the quality of weld.
(3) With the addition of V, Ti, Nb and other special elements, the carbon equivalent decreases and the toughness and strength of the steel tube increases.
(4) The development of hot rolling technology improves the dimension accuracy of strip and reduces the dimension deviation of welded pipe.
(5) Improve quality inspection methods, such as ultrasonic nondestructive testing, hydraulic testing machine and other equipment, to ensure the quality of the final product.