Key points of production process of spiral welded pipe
Spiral welded pipe (SSAW pipe) is a kind of spiral seam steel pipe made of strip steel coil as raw material, which is welded by automatic double-wire double-sided submerged arc welding process and extruded at room temperature. Water supply engineering, petrochemical industry, chemical industry, electric power industry, agricultural irrigation and urban construction are the fields where spiral welded pipes are mainly used.
The main process characteristics of spiral welded pipe:
1. During the molding process, the residual stress is small and there is no scratch on the surface. The processed spiral welded pipe has incomparable advantages in the size and specification range of diameter and wall thickness, and can meet more requirements of users for spiral steel pipe specifications.
2. Adopt advanced double-sided submerged arc welding technology to deal with some defects, and it is easy to control the welding quality.
3. Carry out 100% quality inspection on the steel pipe, so as to guarantee the product quality.
4. All equipment in the entire production line has the function of networking with the computer data acquisition system to realize real-time data transmission, and the technical parameters in the production process are controlled by the control room.
For the heating process, heat treatment heating equipment and heating medium should be selected. What happens or is easy to happen here is that the surface of the part will be affected by the oxidizing heating medium, and the heating temperature exceeds the process requirements. If the austenite grains are too thick, even the grain boundaries will melt, which will seriously affect the appearance and internal quality of the parts. Therefore, in the actual process, feasible measures should be taken to analyze such defects.
The defective parts produced during tempering are quenched to obtain a quenched martensite structure with high hardness or a lower bainite structure with a slightly lower hardness, but the structure is unstable and brittle. When used in production, it is tempered to obtain the desired structure and properties. Therefore, tempering process parameters will have an important impact on the heat treatment quality of parts, such as hardness, tempering brittleness, tempering cracks and other defects, and measures should be taken to avoid these defects during tempering.
The correct heat treatment process is the premise and basis for ensuring the qualified heat treatment quality of parts. Once the above quality problems are found, they can be solved from the aspects of people, machines, materials, methods, links, inspections, etc. Through analysis and judgment, the root cause of the defect can be found.
The main process characteristics of spiral welded pipe:
1. During the molding process, the residual stress is small and there is no scratch on the surface. The processed spiral welded pipe has incomparable advantages in the size and specification range of diameter and wall thickness, and can meet more requirements of users for spiral steel pipe specifications.
2. Adopt advanced double-sided submerged arc welding technology to deal with some defects, and it is easy to control the welding quality.
3. Carry out 100% quality inspection on the steel pipe, so as to guarantee the product quality.
4. All equipment in the entire production line has the function of networking with the computer data acquisition system to realize real-time data transmission, and the technical parameters in the production process are controlled by the control room.
For the heating process, heat treatment heating equipment and heating medium should be selected. What happens or is easy to happen here is that the surface of the part will be affected by the oxidizing heating medium, and the heating temperature exceeds the process requirements. If the austenite grains are too thick, even the grain boundaries will melt, which will seriously affect the appearance and internal quality of the parts. Therefore, in the actual process, feasible measures should be taken to analyze such defects.
The defective parts produced during tempering are quenched to obtain a quenched martensite structure with high hardness or a lower bainite structure with a slightly lower hardness, but the structure is unstable and brittle. When used in production, it is tempered to obtain the desired structure and properties. Therefore, tempering process parameters will have an important impact on the heat treatment quality of parts, such as hardness, tempering brittleness, tempering cracks and other defects, and measures should be taken to avoid these defects during tempering.
The correct heat treatment process is the premise and basis for ensuring the qualified heat treatment quality of parts. Once the above quality problems are found, they can be solved from the aspects of people, machines, materials, methods, links, inspections, etc. Through analysis and judgment, the root cause of the defect can be found.
