Seamless steel pipe & tube welding methods and techniques
Seamless steel pipes may require welding during manufacture, installation and use. Here are several welding methods for seamless steel pipes:
1. Pipe to pipe welding
Align the ends of two seamless steel pipes and then weld them, including manual arc welding, gas shielded welding and submerged arc welding.
2. Pipe to flange welding
Welding seamless steel pipes and flanges after butt jointing is a common connection method in pipeline systems, including manual arc welding, gas shielded welding and submerged arc welding.
3. Pipe end to pipe side fillet welding
Align the pipe ends and weld on the side of the pipe, usually using manual arc welding or TIG welding methods, which are suitable for low-volume production and low-demand situations, and the cost is low.
4. Pipe end to pipe end fillet welding
Align the pipe ends and weld them at the pipe ends, usually using automated welding robots or TIG welding methods, which are suitable for mass production, high demand, and high safety requirements.
In general, there are many different welding methods for different application fields and specific requirements of seamless steel pipes. Choosing the appropriate welding method can improve the welding quality and ensure the safety and use effect of seamless steel pipes.
Seamless steel pipe welding skills sharing:
1. Selection of welding parameters
The selection of welding parameters plays a decisive role in the quality of welding. Usually, the appropriate selection of welding current, voltage and electrode type can effectively reduce the welding defect rate. Compared with ordinary steel pipes, high-pressure seamless steel pipes have higher requirements for welding parameters. In particular, it is necessary to master the balance between welding current and welding speed to avoid the generation of welding slag.
2. Material preparation process
Steel pipes need to be passivated before welding to remove dirt and oxide layers in the pipes, and at the same time, they need to be cut and expanded. The most important thing at this time is to maintain the consistency of the cuts and the straightness and roundness of the tube. It is also necessary to master the internal and external protection process of the pipe to avoid contamination and oxidation.
3. Selection of welding equipment
Welding equipment selection also plays a vital role in welding. Arc welding, gas shielded welding and TIG welding are usually used. Different welding equipment is suitable for different welding processes and parameter selection requirements. For the selection of welding equipment for seamless steel pipes, the selection needs to be based on actual needs to avoid insufficient equipment or waste that affects the guarantee of welding quality.
4. Welding process
The welding process is the key to achieving high-quality welds. The manual welding process with arc is usually used. The main thing is to pay attention to the stability of the arc, uniform welding temperature and ensure consistent welding speed. In addition, it is also necessary to master a reasonable welding sequence to avoid excessive welding, because these may lead to an increase in the welding defect rate, thus affecting the service life of high-pressure seamless steel pipes.
5. Quality control
In the seamless steel pipe welding process, quality control is also crucial. Welding defects in high-pressure seamless steel pipes may affect the quality of the entire project. Therefore, after welding, relevant testing is required to determine whether the welding quality meets the standard. In case welding defects are discovered, corresponding measures need to be taken to repair or re-weld to ensure the quality and safety of seamless steel pipes.
Read more: Seamless Steel Pipe Manufacturer Process
