Post-heating refers to post-welding heating to prevent sudden cooling.

Post-weld heat treatment is to better combine the weld metal with the base metal through heat treatment (the steel grade of the welding material and the base metal is often inconsistent, and it is better to combine by heating and diffusion).

Precautions for post-heating:

Generally, it is heated by flame at 250~350℃ for about half an hour. Post-weld heat treatment depends on the material and thickness. Just look at the standard NB/T 470 15. The temperature is generally high, about 600℃. You can use a stove or ceramics to heat the blanket. Pay attention to heating evenly after heating.

The purpose of post-heating is mainly as follows:?

Promote the diffusion of hydrogen in the weld to escape as soon as possible and avoid hydrogen-induced cracks;

Properly slow down the residual stress of welded joints to prevent cold cracks or reheat cracks.