If the wall thickness of the elbow is relatively thick, it is best to perform stress relief heat treatment on the weldment immediately after welding. This is especially true for large-thickness weldments Q235B, high-rigidity structural parts, and weldments that work under severe conditions (dynamic load or impact load). The tempering temperature for stress relief is 600～650℃. For thin-walled elbows, stress heat treatment is not necessary after welding.
The yield rate is a comprehensive technical and economic index in the production of medium and heavy plates such as A283 Grade C standard. Increasing the yield rate can not only reduce the loss of metal, but it is also vital to the economic benefits of the steel enterprise. The influencing factors of the yield of medium and heavy plates are various, for example, the variety structure, negative deviation rolling level, plate shape control level, cutting loss, rolling waste and burning loss, etc.
We have 4 typical production lines A283 Grade C standard, which can produce hot rolled Seamless, LSAW, ERW and SSAW pipes. The Seamless pipe production line range is OD 10.3mm-965.2mm, wall thickness 1.0mm-60mm, Annual capacity is 500 thousand tons. LSAW pipe production line range is OD 406mm-1524mm, wall thickness 6mm-50mm, Annual capacity is 150 thousand tons.