20CrMo steel has the characteristics of high hardness, high elongation, good toughness and excellent corrosion resistance. In the process of use, 20 CrMo Steel pipe is easy to crack, folding and other defects, so that its service life is greatly reduced.
Welding performance
When welding 20 CrMo steel, the process of preheating, slow cooling and fast cooling can be adopted.
Preheat: Preheat 20 CrMo steel at 950℃ for 1h and hold for 30 min.
Slow cooling: The welding rod is used to weld 20 CrMo steel at a temperature of 40~50℃, so that it is overheated, so as to avoid deformation after welding.
In order to avoid cracks in welded parts, strict surface quenching should be carried out;
Fast cold welding is not suitable for 20 CrMo steel with large weld metal content, carbon content greater than 0.15% or high manganese content.
20 CrMo steel is prone to crack during quenching. Strict surface quenching treatment should be carried out to ensure that the weldment does not appear cold deformation.
Weld 20 CrMo steel in strict accordance with the electrode instructions for use.
Welding method of 20CrMo steel: DC or AC welding machine.
Tungsten argon arc welding, argon or nitrogen gas protection.
When the thickness of filling and cladding metal and coating is less than 5 mm, CO2 gas shielded welding can be used; if it is less than 5 mm, J51A gas cutting torch should be used.
Pay attention to the preheating temperature and the Angle of the electrode when welding.
20CrMo steel has good cracking resistance, and its toughness increases with the increase of chromium content. When the carbon content of steel exceeds 0.025%, attention should be paid to prevent welding cracks when welding 20CrMo steel materials.
Just like you, 70% customers choose long-term cooperation with BBN steel not only for our good product and service quality, good reputation in the international market, but also for our experienced one-stop raw material supply and further steel processing!
