Anhui Tianda Oil Pipe : The company successfully developed high toughness structure ...

136J, 148J, 138J, average 140J, with the last group of 219x18.26 -50 impact test results announced, marking the company developed a high toughness structure tube to achieve success.
In recent years, with the steel used in cold area construction, mechanical structure with steel, marine steel, low temperature steel pipeline transport etc. with the rapid growth of steel demand and the strength, toughness and excellent welding performance of high temperature steel development has become an inevitable trend. The strength and toughness of high demand, the traditional process using quenched and tempered state of delivery in order to achieve high strength and high toughness. But steel after quenching and tempering after welding, the heat affected zone properties decreased significantly, can not achieve the strength and toughness of engineering requirements, caused a great security risk. High strength need to be normalized, high toughness and good welding performance of low temperature pipe. Based on this, the company the Mn in the steel based on the traditional Cr-Mo-V-Ni added alloy elements, controlling carbon equivalent. The ferrite pearlite strengthening, toughening mechanism, by normalizing pearlite, with fine carbide iron obtained Metallographic microstructure of the element matrix. The experimental results show that the strength, toughness and welding performance are all good.
The above experimental results, marking the company has produced the European standard S420NH EN10210-1, S420NLH, S460NH, S460NLH series of high strength, high toughness, with excellent welding properties of low temperature structural steel pipe.