AWS C4.3/C4.3M PDF

This manual describes the equipment, procedures, and safe practices for oxyfuel gas heating torch operation. It is written for the operators of torches using single or multiple heating tips and heads. It is also recommended for management personnel associated with the oxyfuel gas heating torch operation and process.

Oxyfuel heating is an operation whereby various metals are heated in order to perform the following operations:

(1) Straightening and bending with mechanical force

(2) Flame straightening, and cambering

(3) Stress relieving

(4) Preweld and postweld heating

(5) Fusion of coatings

(6) Flame hardening

(7) Flame shrinking

The metal is heated by the direct application of single or multi flames to a desired elevated temperature. The heating process may be applied to all types of metal forms or shapes. An operator can make proper compensation for the effect of the metallurgical conditions, part geometry, and physical changes that may occur during the heating process.

In general, torch heating does not require any lengthy start-up. Operations can be performed in most locations, confined to very limited areas, under almost any conditions and, with relatively low equipment cost. Torch heating can also be performed on completed structures without dismantling them.