What is the P690QL1 steel welding process?

EN10028-6 P690QL1 grade is a quenched and tempered steel material for weldable fine grain pressure purposes. It is weldable and can be used in high temperature equipment and pressure vessel.

P690QL1 steel welding process

The submerged arc welding method of P690QL1 and Q370R dissimilar steel is characterized in that the method includes the following steps:

1) Submerged arc welding groove adopts asymmetric X-shaped groove, and the welding materials used are MCJQ-1 welding wire and SJ101 sintered flux;

2) Preheat P690QL1 and Q370R steel plates;

3) Submerged arc welding adopts DC reverse connection, current is 500-550A, voltage is 26-32V, welding speed is 35-1000px/min, line energy is 20-35kJ/cm, flux baking temperature is 350×2h;

4) Carry out hydrogen elimination heat treatment after welding;

5) After the welding seam has passed the non-destructive test, perform post-weld stress relief heat treatment at a constant temperature of 565 ± 20, and keep it for 2 hours. The submerged arc welding method of the present invention effectively solves the large difference in strength between the two kinds of dissimilar steels, and effectively guarantees the quality of the high-strength dissimilar steel welding joint.