Year1
- 规格：
- DN250
- 材质：
- Q235B
Tel
/ (Ministry standard, also called spiral seam submerged arc welded steel pipe for ordinary fluid transportation pipelines), / (National standard, also called oil and gas industry transportation steel pipe delivery technical conditions, graded steel pipes (graded steel pipes with strict requirements so far)), (American Petroleum Institute, also called pipeline steel pipes, which are divided into two levels), / (pile Use spiral seam submerged arc welded steel pipe).
, often formed by warm extrusion, and welded by automatic double-wire double-sided submerged arc welding process.
）The raw materials are steel strip coil, welding wire and flux. They must undergo strict physical and chemical inspections before being put into use.
) The steel strips are butt-jointed head to tail, using single-wire or double-wire submerged arc welding, and automatic submerged arc welding is used for repair welding after being rolled into steel pipes.
) Before forming, the strip steel is leveled, trimmed, planed, surface cleaned, transported and pre-bent.
) Electric contact pressure gauges are used to control the pressure of the cylinders on both sides of the conveyor to ensure smooth transportation of strip steel.
）Using external control or internal control roller forming. Beijing spiral steel pipe/spiral steel pipe factory/spiral steel pipe price
) uses a weld gap control device to ensure that the weld gap meets the welding requirements. The pipe diameter, offset amount and weld gap are all be strictly controlled.
) Both internal and external welding use American Lincoln welding machines for single-wire or double-wire submerged arc welding to obtain stable welding specifications.
) All completed welds have been inspected by an online continuous ultrasonic automatic flaw detector, ensuring 100% non-destructive testing coverage of spiral welds.
) Use an air plasma cutting machine to cut the steel pipe into individual pieces.
) After being cut into individual steel pipes, each batch of steel pipes must undergo a strict first inspection system to check the mechanical properties, chemical composition, fusion status, surface quality of the steel pipe and the process of the weld. Non-destructive testing is required to ensure that the pipe making process is qualified before it can be officially put into production.
) The parts with continuous sonic flaw detection marks on the welds will undergo manual ultrasonic and radiographic re-examination. If there are indeed defects, they will be repaired and then undergo non-destructive inspection again until it is confirmed that the defects have been eliminated.
) The butt welds of the strip steel and the pipes where the T-shaped joints intersect with the spiral welds are all inspected by radiography or radiographs.
) Each steel pipe has been tested by hydrostatic pressure, and the pressure is radially sealed. The test pressure and time are strictly controlled by the steel pipe water pressure microcomputer detection device. Test parameters are automatically printed and recorded.
) The pipe end is machined to accurately control the end face verticality, bevel angle and blunt edge. Spiral pipes and their specification classification Spiral seam submerged arc welded steel pipes for transporting pressurized fluids () are mainly used for transporting oil and natural gas pipelines. Spiral seam high-frequency welded steel pipes for transporting pressurized fluids () are used for high-frequency lap welding. Welded, spiral seam high-frequency welded steel pipe used for pressure fluid transportation. The steel pipe has strong pressure-bearing capacity, good plasticity, and is easy to weld and process. It is a spiral submerged arc welded steel pipe () for general low-pressure fluid transportation. It is made by double-sided automatic submerged arc welding or single-sided welding and is used for water, gas, air and Submerged arc welded steel pipes for conveying common low-pressure fluids such as steam.
WhatsApp
