At present, steel pipes are widely used and have many types. Thermal expansion carbon steel pipe is one of them. It has many advantages, but of course it is not without any disadvantages. The following is a detailed explanation of the advantages and disadvantages of hot-expanded steel pipes by carbon steel pipe manufacturers, hoping to help you understand this product.
Advantages of thermal expansion carbon steel pipe:
It can destroy the forging structure of the steel pipe, refine the grain size of the heat-expandable steel pipe, eliminate the microstructure defects, make the heat-expandable steel pipe compact in structure and improve the mechanical properties. This improvement is mainly reflected in the rolling direction, so that the heat-expandable steel pipe no longer has the corresponding isotropy, and the bubbles, cracks and porosity generated in the pouring process can also be welded under the function of high temperature and high pressure.
Disadvantages of thermal expansion carbon steel pipe:
1. Residual stress caused by uneven cooling. Residual stress refers to the internal self-equilibrium stress without external force. Such residual stresses exist in heat-expandable steel pipes of various cross-sections. Generally, the larger the section size of the section steel, the greater the residual stress. Residual stress is naturally self-phase equilibrium, but it still has a corresponding effect on the characteristics of steel parts under the action of external forces. Such aspects as deformation, non-chaos, fatigue resistance, etc. may have adverse effects.
2. After thermal expansion, the non-metallic inclusions (mainly composed of sulfides and oxides and silicates) in the thermal expansion steel pipe are pressed into thin sheets, resulting in delamination (interlayer). Delamination will seriously damage the tensile properties of the heat-expandable steel pipe along the thickness direction, and when the weld shrinks, interlaminar tearing is likely to occur. The partial strain due to welding shrinkage is usually several times the yield point strain and much higher than the partial strain due to the load.