1.UOE Forming - The 'Classic Solution' for Large-Diameter Pipeline Steel Pipes
UOE(U-ing → O-ing → Expanding) is one of the most widely used forming processes in large-diameter and thick-walled welded pipes at present. Its greatest feature is high molding precision and good roundness, and it is especially suitable for high pressure and high strength environment.
Process flow:
U-shaped stamping → O-shaped coiling → internal and external welding → expanding treatment → sizing → inspection.
Advantages:
- The pipe body has high strength and good dimensional accuracy.
- The residual stress is small, which is beneficial to high pressure transportation.
- Widely used in long-distance oil and gas pipelines (API 5L)
Scope of application:
Large-diameter, thick-walled straight-seam pipes are suitable for high-grade pipeline steels such as X60, X70, and X80.
2.JCOE forming-a highly flexible straight welded pipe process
JCOE is a step-by-step compression molding method developed on the basis of UOE, which is more flexible through multiple molding of "J → C → O".
Process characteristics:
- The steel plate is bent into J-shape, C-shape and then rolled into O-shape.
- Suitable for orders with small batch, multiple specifications and special thickness.
- Expanding (E) process improves roundness and dimensional stability.
Advantages:
- High flexibility, suitable for different wall thicknesses and medium and large caliber.
- Has stronger adaptability to steel plate raw materials.
- Welding stability, often used in structural pipes, pressure pipelines, urban water projects.
Applicable standards:
GB/T 9711, API 5L, EN 10219, etc.
3.Longitudinal welded pipe (ERW/LSAW)-the most commonly used and widely used.
Straight welded pipes can be divided into two categories:
(1)ERW high frequency welded pipe (≤ 26 ")
With high production efficiency and low cost, it is the most common type of exhaust pipe in construction, machinery and automobile.
Advantages:
- The weld seam is formed quickly and welded evenly.
- Good appearance and high precision.
- Suitable for thin-walled and medium-thick steel pipes
Application:
- Building structure
- Low-pressure fluid transportation (such as water supply and drainage)
- Steel structure support, scaffolding
(2)LSAW longitudinal submerged arc welded pipe (large diameter)
Closer to UOE/JCOE, mainly used for pressure transportation.
Advantages:
- Strong weld performance and stable quality.
- Large caliber and wide range of wall thickness
- Commonly used in oil and gas transportation, offshore structures and bridges.
4.spiral welded pipe (SSAW)-the most cost-effective large diameter pipe.
The coiling method of spiral pipe is to coil the steel strip into a spiral shape at a certain angle and weld it, which is suitable for the continuous production of large-size steel pipes.
Advantages:
- It can produce large-diameter and super-long steel pipes.
- Low cost and high material utilization rate.
- Fast production speed.
Insufficient:
- The longer weld has a slight influence on the bearing capacity.
- It is seldom used in high-pressure and high-strength scenes.
Typical application:
- Urban water supply and drainage engineering.
- Pipe for pile foundation.
- Low pressure conveying system.
