- Steel strip coil, welding wire, and flux are the raw ingredients. Before being used, it must pass stringent physical and chemical tests.
- After the steel pipe is rolled, use automatic submerged arc welding to repair welding using single wire or double wire submerged arc welding.
- The strip is leveled, cut, planed, surface cleaned, and pre-bent before forming.
- Control the pressure of the cylinder on both sides of the conveyor with an electric contact pressure gauge to ensure that the strip is conveyed smoothly.
- Roll molding is controlled externally or internally.
- The amount of misalignment and the weld gap are rigorously regulated using the weld gap control device to ensure that the weld gap fulfills the welding standards and the spiral welded pipe diameter.
- Single-wire or double-wire submerged arc welding using Lincoln welding equipment from the United States is used for internal and external welding.
- In non-destructive testing, the final welds were evaluated by an online continuous ultrasonic automatic defect detector, ensuring 100 percent coverage of the spiral welds. If there are any problems, an automatic alarm will sound, and a spray mark will appear, allowing the production worker to alter the process parameters at any time to eliminate the errors as quickly as possible.
- An air plasma cutting machine sliced the spiral welded pipes into individual pieces.
- The spiral welded pipe was tested for mechanical properties, chemical composition, and bonding conditions.
- After manual ultrasonic and X-ray inspection, the part of the weld with continuous acoustic fault detection marks, If the spiral welded pipe has a flaw, it must be subjected to nondestructive examination following repair until the defect is proven to remove.
- X-ray television or film are used to inspect the spiral welded pipe where the butt weld of strip steel and the t-joint intersecting the spiral weld are located.
- A hydrostatic pressure test is performed on each spiral welded pipe, and the pressure is radically sealed.
Post time: Apr-12-2022