Welding and other manufacturing processes where significant heat is applied can leave stresses within the workpiece and during the subsequent cooling phase distortions may develop. Flame straightening is an efficient, well-established method of correcting the weld distortion without impairing the material.
Removing deformations with an oxy-acetylene flame
This process is based on the physical principle that metals expand when heated and contract when cooled. If expansion is restricted, stresses build up. Upon cooling, some areas will then contract more than others causing undesirable compressive stresses that will lead to plastic deformations. An oxy-acetylene flame is used to rapidly heat a well-defined section of the workpiece and remove these deformations. Suitable materials include steel, nickel alloys, copper, aluminum and titanium.
Ideal equipment for flame straightening
The appropriate equipment for flame straightening depends on the type of material and thickness of the workpiece. Complementing our range of standard LINDOFLAMM® burners for regular straightening jobs, we offer a range of specialised LINDOFLAMM® torches. Here we tailor the shape and performance of the torch to meet your individual flame straightening challenge, making these solutions ideal for large-diameter pipes or thick-walled workpieces.
The right fuel gas for flame straightening
During flame straightening, component sections must be precisely and locally heated to correct temperatures over a short time period. This is only possible if the workpiece surface is provided with a high heat-flux density in a very restricted space. Although various fuel gases can be used for flame straightening projects, the highest flame temperatures and intensities for rapid heating are achieved with acetylene and oxygen.