New challenge

In June,2016, Hunan Great Steel Pipe Co., LTD. received a challenge order with below request and conducted researches immediately:


1) Pipe Specification: Φ1219 * 28.6 * 12000 mm, Steel Grade: API 5 l PSL2 X70M


2) At temperature -41℃，for V-shaped notch specimen, CVN test from welding seam and HAZ, minimum impact value for single specimen shall ≥30J and average impact value shall ≥40J. And CVN test from base material, minimum impact value for single specimen shall ≥60J and average impact value shall ≥80J.


After multiple welding procedure tests, Yulong has successfully optimized the existing welding procedure which is adopted during the pilot production. And after various physical and chemical properties testing and quality inspection for the pilot produced pipe, all the quality indexes of the carbon steel pipe are satisfied with specification standard and customer requirements. Since getting the production approval from the customer, we have already produced 4866MT qualified pipes.


The successful production of DSAW steel pipe with large diameter, thick wall thickness and high steel grade under -41℃ low temperature impact test requirements marks Jiangsu Yulong Steel Pipe Co., LTD. has gained a big breakthrough in pipe manufacturing technology and will have a greater advantage in the future market competition.