Welding head treatment process after welding

Overall heat treatment
As far as possible, the welding head should be post-welded pipe components in the heat treatment furnace, but the components shall not be welded together with valves and other components.

Sectional heat treatment
When the welded piping components cannot be added with a heat treatment furnace, the heat treatment allows segmentation. In the segmented heat treatment, the length of the repeated heating is at least 300mm. At the same time, it is necessary to protect the outside of the furnace to prevent harmful temperature gradients.

Local heat treatment
When local heat treatment is performed on the weld, the wiring pipe and the branched circumferential band should be heated until the specified temperature range exists on the entire pipe section, and then gradually decrease until it exceeds the band including the weld or weld. Curved or formed part, and at least 25mm from the end.

PWHT safety regulations
A safety warning line must be set to prohibit irrelevant personnel from entering the heat treatment process.
Operators must be trained in heat treatment operations familiar with the operation technology.
Flammable materials with a heat treatment range of 30m should be removed.
Operators must be equipped with personal protective equipment, such as cotton gloves, sunglasses, etc.