Pre Weld Heat Treatment

Techno Weld specializes in local Pre-Weld Heat Treatment of carbon steel and alloy steel piping welds by means of the electrical resistance method, in the form of ceramic heater pads and by using a source of electricity as a source of heating for stress-relieving of weld joints.

The penetrant is applied to the surface and allowed to remain on the surface for a prescribed time (dwell time); the penetrant liquid will be drawn into any surface opening by capillary action. Following the removal of the excess penetrant, an application of the developer reverses the capillary action and draws the penetrant from the flaw. The resultant indications reveal the presence of the flaw so that it can be visually inspected and evaluated.

All Heat Treatment services are designed to minimize downtime, improve structural integrity and enhance effective plant life. Additionally, depending on the mobility of the required equipment many of our heating processes can be applied on-site or at your facility.

Preheating involves rising the temperature of the parent material locally, on both sides of the joint to a value above ambient. The need for preheating is usually determined by the pertinent fabrication code and verified by the weld procedure qualification test.