The quality inspection methods for spiral welded steel pipes are as follows:
1. Visual inspection of spiral welded steel pipes
Visual inspection of welded joints is a simple procedure with various methods. It is an important part of the finished product inspection of spiral welded steel pipes, mainly to find surface defects and dimensional deviations in the welds. Generally, it is done by visual observation, using standard gauges and magnifying glasses for testing. If defects exist on the surface of the weld, there may be defects within the weld itself.
2. Physical inspection methods for spiral welded steel pipes
Physical inspection methods utilize certain physical phenomena for inspection. Non-destructive testing methods are generally used to inspect internal defects in materials or spiral welded steel pipe parts. X-ray flaw detection is one of the most commonly used non-destructive testing methods for spiral welded steel pipes. This method is characterized by its objectivity and directness, with real-time X-ray imaging, automatic defect identification, location, and measurement by software.
3. Strength test of spiral welded steel pipes for pressure vessels
In addition to sealing tests, pressure vessels also undergo strength tests. These typically include hydraulic tests and pneumatic tests. They can test the weld density of containers and pipes operating under pressure. Pneumatic testing is more sensitive and faster than hydraulic testing, and the tested product does not require drainage, especially for products that are difficult to drain. However, the risk of this test is higher than that of hydraulic testing. Appropriate safety and technical measures must be followed during the testing process to prevent accidents.
4. Compaction Test of Spiral Steel Pipes
For welded containers storing liquids or gases, spiral steel pipes without dense defects such as penetrating cracks, pores, slag, impermeability, and loose structure can be used to determine compaction. Compaction testing methods include: kerosene testing, water testing, etc.
5. Hydrostatic Pressure Test of Spiral Steel Pipes
Each spiral steel pipe should undergo a hydrostatic pressure test without leakage. The test pressure is calculated as P = 2ST / D, where S is the hydrostatic pressure test pressure in MPa. The hydrostatic pressure test pressure is 60% of the output specified in the corresponding standard. Adjustment Time: For D < 508, the test pressure holding time shall not be less than 5 seconds; for D≥ 508, the test pressure holding time shall not be less than 10 seconds.
6. Inspection of Spiral Steel Pipe Welds
Non-destructive testing of the steel head welds and circumferential joints of spiral steel pipes shall be performed using X-ray or ultrasonic testing. For spiral steel pipes transporting flammable general fluids, 100% X-ray or ultrasonic testing shall be performed on the spiral welds. For spiral steel pipes transporting general fluids such as water, sewage, air, and heating steam, the spiral welds shall be inspected using X-ray or ultrasonic testing. The advantages of X-ray testing are objective imaging, low requirements for professional expertise, and data storage and traceability.
Post time: Jan-26-2026