Detailed acceptance criteria for welded steel pipe

Acceptance of welded steel pipe is an important step to ensure that its quality and performance standards, generally includes the following key aspects.
Appearance quality is extremely important, the surface of the steel pipe should be smooth, there can be no cracks, folding, scars, delamination and scratches and other defects, the weld needs to be smooth and uniform, no porosity, slag, not welded through and other welding problems.
Dimensional accuracy can not be ignored, the outer diameter, wall thickness, length and other dimensions of the steel pipe should be carefully checked to see whether it is in line with the deviation range specified in the contract or standard.
Chemical composition must be tested to determine the content of carbon, silicon, manganese, phosphorus, sulfur and other major elements in the steel pipe to ensure that it is within the specified range.
Mechanical properties are the key indicators, tensile strength, yield strength, elongation and other mechanical properties to meet the appropriate standards.
Hydraulic test can not be less, according to the specified pressure and time, the steel pipe can not have leakage or rupture.
Non-destructive testing is also critical, such as ultrasonic testing, ray testing, etc., to check the inside of the weld, there can be no excessive defects.
Marking and packaging are also important, the steel pipe should have clear and accurate marking, including material, specification, standard number, furnace lot number, etc. The packaging should be well protected to prevent damage during transportation and storage.
Quality documents are indispensable, suppliers should provide material sheets, inspection reports, certificates of conformity, etc., to prove that the quality of steel pipe meets the requirements.
It should be noted that there may be specific acceptance standards and additional requirements for welded steel pipes for different applications and industries, which should be considered comprehensively during acceptance and inspected strictly in accordance with the standards and contracts.