LSAW welded steel pipes

On the double submerged arc welding line for large-diameter double-seam welded steel pipe, the steel strip is progressively bent into the tubular form. This ensures the internal and external stress can be evenly distributed over the pipe so that the pipe can maintain a good shape. One typical feature of the DSAW line is that it offers a wide range of specifications and enables faster, easier changeover change-over. In fact, the line can produce any diameters of welded pipes within its capacity.

General Process Flow
Vacuum Lifting - Ultrasonic Testing - Edge Crimping - Press Bending - Surface Inspection - Edge Milling - Roll Bending - Tack Welding - Tab Welding - Internal Welding - External Welding - Tab Removal - Ultrasonic Testing - X-Ray Testing - Mechanical Expanding - Hydrostatic Testing - End Facing/Beveling) - Ultrasonic Testing - X-Ray & Film Examination - Final Inspection - Weighing and Measuring - Coating - Marking

Diameter: 325-1420mm (14"-60")
Thickness: 8-60mm
Length: 3-13m
Steel Material: Q235A, Q235B, Q345, ASTM A53/106, API 5L GR.A/B, A672 B60 CL22, L245 L290 X42 X46 X70 X80
Standards: API 5L, ASTM A672, SY/T5768-2006, GB/T3091-2008, GB/T9711-1

Applications
Our LSAW steel pipe is used to transfer oil, gas, and slurry to construction site. It is also used in the chemical plant, power plant, and offshore drill platform.

Depending on different product specifications, features, and applications, we will choose diversified means of packing and transport. This ensures the product can be delivered to customer site in wholesome condition.

Packaging
Ordered products will first be coated with a layer of film. Then they are packed in bundles with steel strip.

Transport
The products can be put into a container or loaded individually. They can be transported by train, car, or plane.

The double submerge arc welded pipe is made of steel plate or steel strip that has been bent and its joint is welded together to form a tube with uniform wall thickness and high dimensional accuracy.

Double submerged arc welding is a simple process that enables high productivity and a wide range of specifications while requiring little investment in the equipment used. It can produces two forms of seams, longitudinal and helical. However, this process does have drawbacks. Pipes coming out of the DSAW line can hardly be used in the petrochemical equipment.

Along with the advances in industrial technology and welding and inspection techniques, the LSAW steel pipe now can be available with improved weld quality and more diversified specifications. This also leads to a boost in LSAW pipe applications in petrochemical equipment. When the nominal diameter of the pipe reaches beyond 600mm, it will be more different to produce a seamless pipe. In that case, the use of LSAW steel pipe in transferring fluids will prevail.