The quality of spiral steel pipe welds directly affects the pipeline's pressure resistance, corrosion resistance, and service life. Inspection must adhere to national standards, employing non-destructive testing (NDT) as the primary method and visual inspection as a supplementary method to control welding quality throughout the entire process.
Visual inspection is the first step. Inspectors use tools such as strong light, rulers, and weld inspection gauges to observe the weld surface for defects such as cracks, porosity, slag inclusions, incomplete penetration, undercut, and weld beads. They measure the weld reinforcement and width to ensure they meet process requirements, confirming uniform weld formation, smooth transitions, and the absence of obvious deformation and spatter. Welds that fail visual inspection are not permitted to proceed to subsequent NDT.
Non-destructive testing is the core step. Commonly used methods include ultrasonic testing, radiographic testing, magnetic particle testing, and penetrant testing. Ultrasonic testing is fast and highly sensitive, accurately detecting area-type defects such as incomplete penetration, lack of fusion, and cracks within the weld. It is suitable for rapid online inspection and is widely used for quality monitoring in the production process. Radiographic testing, using X-ray or gamma-ray imaging, visually reveals the shape, size, and location of internal defects in welds. Results can be stored on film, serving as a crucial basis for quality acceptance.
Magnetic particle testing is suitable for detecting surface and near-surface defects in ferromagnetic materials. It identifies cracks, porosity, and other problems by observing the accumulation of magnetic particles; it is simple to operate and relatively inexpensive. Penetrant testing is primarily used for non-magnetic steel pipes such as stainless steel. It utilizes penetrant to develop defects and identify surface openings.
In addition, some pressure-bearing pipelines require hydrostatic testing. Holding the pressure at the designed pressure for the specified time checks for leaks and deformation in the welds, verifying overall sealing and structural strength.
The combination of multiple testing methods allows for a comprehensive investigation of potential weld defects in spiral steel pipes, ensuring that the product meets the safety requirements for use in water supply and drainage, oil and gas transportation, municipal engineering, and industrial pipelines.
GB/T 7714
Wang Li,Zhang Jun,Li Jihong Research progress on non-destructive testing technology for spiral submerged arc welded pipe welds[J].Hot Processing Technology,2020,49(07):10-14
MLA
Wang,Li,et al.“Research Progress on Nondestructive Testing Technology for Spiral Submerged Arc Welded Pipe Welds.”Hot Working Technology,vol.49,no.7,2020,pp.10-14.
APA
Wang,L.,Zhang,J.,&Li,J.(2020).Research progress on nondestructive testing technology for spiral submerged arc welded pipe welds.Hot Working Technology,49(7),10-14.
