Precision stainless steel tubes, as bathroom sleeves and mechanical connection components, have certain requirements for the processing of the tubes. However, many factories always encounter a series of problems during deep processing. Among them, there are cracks, warping, deformations and even dimensional changes in the later stage caused by stress. Next, let's take a look at the causes of stress in precision stainless steel pipes and the methods to eliminate it.
I. Causes of Stress Generation
When welding precision stainless steel pipes, the temperature near the solitary pit is high while that far away is low, resulting in uneven thermal expansion at the welding position. The heated part is elongated accordingly, while the unheated part remains at its original length. Therefore, the elongation of hot metals is hindered by cold metals, which limits the elongation of hot metals, generating compressive stress in hot metals and tensile stress in cold metals. When the tensile stress generated by the heated stainless steel pipe is greater than the yield point, it will undergo plastic deformation. The yield point of metals generally decreases as the temperature rises, at600℃When is equal to0. When cooling, due to the plastic deformation of the stainless steel precision tube during heating, the length of the contraction of the hot metal part is shorter than when it is not welded. At this point, the hot metal is subjected to tensile stress, while the cold metal is subjected to compressive stress. So,304Stress was generated in the stainless steel pipe.
Ii. Solutions
As stress has various adverse effects on stainless steel precision tubes, including weld cracks, pipe deformation, and decreased corrosion resistance, it is very necessary to eliminate stress. Several methods for eliminating internal stress: One is to eliminate it under natural conditions, which is called natural aging; The second is the heat treatment of objects, which is called thermal aging. The third method is to eliminate it through knocking and vibration, which is called vibration stress relief.
1Natural aging refers to the process of leaving stainless steel pipes under natural conditions for a long time to release residual stress. However, due to the long cycle and low efficiency of natural aging, it is difficult to meet the needs of modern production. This method is inefficient and not very feasible. Generally, few manufacturers would adopt this traditional and time-consuming method.
2Heat aging treatment, as a traditional process, can effectively eliminate residual stress in precision stainless steel tubes and improve material properties to a certain extent. However, at present, most machine tool manufacturers do not have the equipment and conditions to carry out thermal aging treatment on large workpieces, resulting in the residual stress generated during cutting and other processes being unable to be effectively eliminated. Another larger reason is that this method will have an impact on the environment and is not in line with the current development of the scientific environment.
3Vibration stress relief technology can not only eliminate residual stress but also eliminate the peak of residual stress and homogenize residual stress, thereby enhancing the dimensional stability of parts and improving the material properties and fatigue life of stainless steel welded pipes. After being processed by this technical equipment, the deformation of the steel pipe is very small after two months, and the time required for dimensional stability is very short. Compared with natural aging and thermal aging, vibration aging has the advantages of energy conservation, environmental protection and high efficiency. Using this stress relief equipment for stress treatment can help enterprises reduce costs, improve production efficiency and enhance the competitiveness of their products. This is also strongly advocated by today's resource-conserving and environment-friendly society.
The above content is about the causes of stress in precision stainless steel pipes and the elimination of stress. The generation of stress is inevitable and causes certain damage to stainless steel pipes. Therefore, the elimination treatment of stress is also very necessary. Stress relief for precision stainless steel tubes is generally achieved through natural aging, thermal aging and vibration aging. Among them, vibration stress relief is highly recommended. It can reduce and homogenize the residual stress inside the pipe, making its dimensional accuracy stable.
Foshan Weilihuang Trading Co., Ltd. is a leading manufacturer specializing in the production and sales of international and domestic stainless steel hardware accessories and its own brands. The company is located at Tianjinli Hardware Accessories Center, Lanshi 2nd Road, Chancheng District, Foshan City, Guangdong Province8seat10-12The number (i.e., the main entrance of the market) has an abundant supply of goods, a complete range of varieties, wide coverage, favorable prices, and stable and superior quality!
The company uses high-quality stainless steel and exquisite craftsmanship to ensure there are no weld marks at the interfaces. Its products feature novel designs, elegant craftsmanship, and long-lasting durability. The company has always adhered to the principle of quality first and reputation first. It is equipped with mature production facilities and has strong technical strength, thus ensuring the quality of its products. The company is willing to make unremitting efforts to join hands with our customers to create a win-win situation and provide high-quality products for our partners.
