Stainless steel has excellent comprehensive properties, appearance and surface properties, and is widely used in all stages. Similarly, stainless steel pipe is no exception. Stainless steel pipe is a kind of hollow section steel, which is generally divided into stainless steel seamless pipe and welded pipe. There are some differences in processing methods and performance. The difference is:
1. Differences in the production process
After rolling the steel plate or strip, the stainless steel welded pipe is welded to form the equipment and mold. The inner wall of the tube usually has welds. Seamless tubes are made of round tube blanks and drilled, cold rolled and cold drawn through the hot extrusion production process. There are no welding points in the tube.
2. Appearance difference of steel pipe
For stainless steel welded pipe, the wall thickness tolerance is very small, and the thickness of the entire circumference is very uniform. The steel pipe has high precision, high brightness of internal and external surfaces, and the length can be set arbitrarily. Seamless steel pipe has low precision, uneven wall thickness, low brightness of internal and external surfaces, high cost of fixed size, internal and external installation and black spots. Therefore, the seamless pipe wall is usually thicker.
3. Difference between performance and price
Seamless pipe has higher corrosion resistance, pressure resistance and high temperature resistance than welded pipe. With the improvement of the manufacturing process of welded pipe, the mechanical properties and mechanical properties are gradually approaching seamless pipe. Seamless tubes are more complex in the manufacturing process and more expensive than welded tubes.
According to the characteristics and differences between stainless steel seamless pipe and welded pipe, reasonable selection and application are required to achieve economic, beautiful and reliable effects.
1. When used as decorative pipe, product pipe and support pipe, the surface effect is generally good, and generally stainless steel welded pipe is required;
2. Generally, stainless steel welded pipes are used for low pressure fluid transportation, such as water, oil, gas, air, hot water or steam and other low pressure systems.
3. Power plants, nuclear power plant boilers, high temperature, high pressure, high strength requirements, high pressure, high pressure infusion pipes, industrial engineering and large equipment infusion pipes should use stainless steel seamless pipes.
4. Stainless steel welded pipe is usually used for liquid transmission below 0.8MPa, while seamless pipe can withstand liquid transmission above 0.8MPa. If the pressure requirement is not high, it is more economical to use welded pipes.