What is the welding and heat treatment of 09MnNiDR steel plate?

09MnNiDR steel plate is ferrite + a little pearlite type low temperature steel, which can be used to prepare - 45 ~ - 70℃ low temperature pressure vessel. Mn and Ni are the main alloying elements in 09MnNiDR steel plate. Mn can improve the strength of steel through solution strengthening, while Ni can improve the low temperature toughness of ferrite and obviously reduce the cold brittle transition temperature. At present, 09MnNiDR steel plate is mainly used in the manufacture of low temperature vessels for petroleum and chemical equipment.

(1) With the increase of heat input and interlayer temperature, the impact absorbed energy of HAZ and SMAW weld decreases. The heat input of electrode arc welding should be within 15 KJ / cm, the heat input of submerged arc welding should be within 15 KJ/ cm, and the interlayer temperature should not exceed 160℃.

(2) The results show that the impact energy of the joint is affected by the post weld heat treatment temperature, and the impact property of the joint heat treated at 590℃ is better than that at 620℃.

(3) For hot formed products, the hot forming temperature should be 910 ~ 960℃, the normalizing temperature should be 910℃, the final annealing temperature should be 590 ~ 620℃, and the best specification is 910℃ + 910℃ + 590℃.