What type of electrode is better for welding 20G boiler steel plate?

J422 electrode (20g is seamless steel tube for high pressure boiler) is used for welding 20g boiler steel plate. The steel is graded according to yield strength. Generally, the electrode with the same or slightly higher tensile strength guarantee value is selected according to the guarantee value of tensile strength of structural steel.

The tensile strength of 20g at 20℃ is 400MPa; the tensile strength of J422 molten gold is not less than 430mpa, and J422 type electrode corresponds to international standard E4303.