Carbon steel welded pipes are mainly divided into three processes: electric resistance welding (ERW), spiral submerged arc welding (SSAW) and straight seam submerged arc welding (LSAW). The carbon steel welded pipes produced by these three processes have their own positioning in the application field because of their different raw materials, forming processes, caliber size and quality.
1. Straight seam electric resistance welded pipe (ERW)
Electric resistance welded pipe is the earliest type of steel pipe produced in my country, with the widest range of applications, the largest number of production units (more than 2,000), and the highest output (accounting for about 80% of the total production capacity of welded pipes). The product specification is Ф20~610mm. played an important role. Since the 1980s, about 30 sets of ERW219-610mm units have been imported from abroad. After years of production practice, the equipment technology level has made great progress, and the product quality is also constantly improving. Because of its low investment, quick effect and wide application range, it has developed rapidly. With the development of plate CSP production process, it provides low-cost, reliable quality raw materials, and creates good conditions for its further development in the future. This part of the products has been developed from the field of fluid transportation and structure to the oil well pipe and line pipe in the field of seamless pipe application.
2. Spiral submerged arc welded pipe (SSAW)
The equipment investment of spiral submerged arc welded pipe is less, because the use of low-cost narrow strip (plate) coil continuous welding to produce large-diameter (Ф1016~3200mm) welded pipe, the production process is simple, the operating cost is low, and it has the advantage of low-cost operation. my country’s oil and gas transmission spiral welded pipe has formed a basic format mainly based on the steel pipe factory affiliated to the petroleum system. Adopting advanced technologies such as low residual stress forming and pipe end mechanical expansion, the quality of the spiral welded pipe that has undergone strict quality control is comparable to that of the straight seam welded pipe. It is the main pipe type used in my country’s long-distance oil and gas pipeline projects. Its production capacity has been able to meet the needs of my country’s long-distance oil and gas pipeline construction, and has been exported in large quantities.
3. Straight seam submerged arc welded pipe (LSAW)
Longitudinal submerged arc welding is an advanced pipe-making technology developed late in my country, and UOE technology was mainly used in the past. In recent years, progressive JCOE has gradually become another new mainstream technology in my country and the world. Longitudinal submerged arc welded pipes are of reliable quality and are widely used in high-pressure oil and gas transportation trunk lines. Due to the relatively large investment of this welded pipe unit, the raw materials used are single wide and thick plates with high cost, the process is complex, the production efficiency is low, and the product cost is high.
Post time: Oct-21-2022