Is preheating required for 15CrMoR welding?
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Is preheating required for welding 15CrMoR, and how can cracks be prevented?
When welding this material, it is essential to carry out proper preheating and post-heating; otherwise, the weld area is prone to cracking.
Preheating is done before welding, and heat treatment is carried out after welding. Chemical engineering construction requires clear specifications and requirements
Preheating is done before welding, and heat treatment is carried out after welding. Chemical engineering construction requires clear specifications and requirements
Preheating is done before welding, and heat treatment is carried out after welding. Chemical engineering construction requires clear specifications and requirements
In accordance with the provisions on welding preheating in NB/T47015-2011, for Fe-4 materials with a minimum tensile strength of more than 410 MPa, or when the joint thickness is greater than 13 mm, the minimum preheating temperature is 120°C℃
Unless there are special requirements, if the thickness is 10 mm or less, preheating is not necessary at the site, and no problems have occurred so far. According to the standards, when the thickness is 13 mm or more, preheating is required. Last year, a certain design institute specified in its polypropylene design documents that for all alloy steel pipes, 100% of the weld joints must undergo heat treatment
Preheating before welding and heat treatment after welding – I read about it in books, but I’m not sure what problems might arise
Depending on the thickness requirements, chromium-molybdenum steel is required for pressure vessels of any thickness, while pipes with a thickness greater than 13 mm need pre-heating before welding and post-weld heat treatment