Judging the quality of SSAW Steel Pipes (spiral seam submerged arc welded steel pipes) is a comprehensive process that involves multiple aspects of inspection and evaluation. Here are some key discrimination methods:

1. Raw material quality inspection

Steel plate material:

Check the material certificate of the steel plate to ensure that it meets the design requirements.

The steel plate should be free of defects such as cracks, inclusions, rust, etc., and the surface should be flat and smooth.

Chemical composition:

Use professional chemical testing instruments, such as direct reading spectrometers, to detect the chemical composition of steel plates.

Ensure that the chemical composition of the steel plate meets relevant standards and design requirements.

2. Welding Quality Assessment

Weld appearance:

The weld seam should be flat, smooth, and free of defects such as cracks, slag inclusions, and porosity.

The width, height, and excess height of the weld seam should meet the design requirements.

Non destructive testing of welds:

Use ultrasonic non-destructive testing equipment, non-destructive testing equipment, and other devices to perform online continuous ultrasonic automatic damage inspection on welds.

The non-destructive testing coverage of welds should meet the requirements of relevant standards.

If defects are found, they should be automatically alarmed and marked with spray paint. Production workers should adjust process parameters accordingly and promptly eliminate defects.

Welding Procedure Qualification:

Check the welding process qualification report to ensure that the welding process meets relevant standards and design requirements.

Pay special attention to the processes of pre welding and internal/external welding (precision welding), as well as the use of weld seam gap control devices.

3. Steel pipe performance testing

Mechanical properties:

Perform mechanical performance tests such as tensile testing, hardness testing, and impact testing on steel pipes.

Ensure that the strength, toughness, and other properties of the steel pipe meet the design requirements.

Hydrostatic test:

Conduct a hydrostatic test on the steel pipe to check its pressure bearing capacity and sealing performance.

The pressure and time of the hydrostatic test should comply with the requirements of relevant standards.

4. Inspection of appearance and dimensions of steel pipes

Steel pipe appearance:

The surface of the steel pipe should be flat and smooth, without defects such as cracks, rust, oil stains, etc.

Check whether the anti-corrosion coating or wrapping material of the steel pipe is intact.

Steel pipe size:

Measure the diameter, wall thickness, and other dimensions of steel pipes using tools such as rulers, levels, tape measures, and vernier calipers.

Ensure that the size of the steel pipe meets the design requirements and relevant standards.

5. Qualifications and certifications of manufacturers

Production license:

Check if the manufacturer has a production license for SSAW steel pipes.

Quality Management System Certification:

Check whether the manufacturer has passed the quality management system certification, such as ISO 9001.

Product certification:

Check whether the steel pipe has passed relevant product certifications, such as API certification.

6. Steel pipe identification and packaging

Steel pipe identification:

There should be clear markings on the steel pipe, including manufacturer, specifications, production date, and other information.

Steel pipe packaging:

Steel pipes should be packaged in appropriate ways to prevent damage during transportation and storage.

In summary, judging the quality of SSAW steel pipes requires comprehensive consideration from multiple aspects such as raw material quality, welding quality, steel pipe performance, steel pipe appearance and size, manufacturer's qualifications and certification, and steel pipe labeling and packaging. Only by comprehensively inspecting these aspects can we ensure that the purchased SSAW steel pipes have excellent quality and meet the design requirements and usage needs.