We have specialized in providing industrial processing equipment for fine chemicals, pesticides, new energy,new materials, and pharmaceutical industries for more than 48 years.
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We have specialized in providing industrial processing equipment for fine chemicals, pesticides, new energy,new materials, and pharmaceutical industries for more than 48 years.
Welding Residual Stress
Welding Residual Stress---The self-balancing internal stress generated in the weldment under the action of non-uniform temperature field, strong restraint, and drastic phase transformation. It is invisible and intangible, and is the "invisible killer" threatening the structural integrity of pressure-bearing equipment.
Challenges Brought by Large-scale Equipment
Manufacturing process Service process
Challenges Brought by Large-scale Equipment
The diameter and wall thickness are extremely large, and the number of weld passes is high, which generates significant residual stress, leading to stress corrosion, creep, and fatigue cracking!
To enhance the inherent safety of major pressure-bearing equipment: It is urgent to eliminate welding residual stress!
Challenges Brought by Large-scale Equipment
Overall heat treatment Segmented overall heat treatment Local heat treatment of joint welds
On-site Local Heat Treatment Difficulties
Unequal thickness structures presents
Thin walls lead to excessive deformation
Pressure-bearing Equipment Difficulties
Why do large pressure-bearing equipment still leak despite strict design, manufacturing, and inspection?
Accurate and Efficient Calculation of Residual Stress
Work1-1：In-plane integration and out-of-plane variable length equivalent heat source model.
Accurate and Efficient Calculation of Residual Stress
Work1-2：Welding residual stress steady-state 
Micro-indentation testing technique
Work2：Residual stress testing by energy indentation method
Advantages：
mprovement of local post-weld heat treatment
Main and auxiliary heating distribution
Induction heating uniformity control method
Induction heating principle
Rib reinforcement deformation control method
Achieve 70% reduction in maximum expansion deformation
