Secondly, it is determined whether the welding area of the workpiece has collapsed and whether the tool has melted.

Third, the workpiece should be outside the fixture. After welding, it shrinks and holds the fixture tightly. Check whether there are burrs hanging on the fixture.

Fourth, make sure there is no problem above. Tap the welding area with a sledgehammer. Never use fire.

Fifthly, the smaller the vertex angle of conical tooling, the more difficult it is to withdraw from the workpiece. If necessary, use a crane to lift or jack the cone at a symmetrical position at its big end. When working, strike the surface of the workpiece evenly with a sledgehammer and slowly withdraw from the workpiece.

I hope the above methods are useful to you.