List two methods of minimizing distortion that can be applied before welding?

1. Proper fit-up: Ensuring that the pieces being welded are properly aligned and fit together before welding can help minimize distortion. This can be achieved by using clamps, jigs, or fixtures to hold the pieces in place during welding.

2. Preheating: Preheating the materials being welded can help reduce the amount of distortion that occurs during welding. By heating the materials to a specific temperature before welding, the thermal stresses that can lead to distortion are minimized.