High-frequency welding management properties: normal temperature mechanical properties, high-temperature mechanical properties, low-temperature properties, and corrosion resistance. The physical and chemical properties of
high-frequency welded pipe mainly depend on the chemical composition of steel, the structure and purity of steel, and the heat treatment method of high-frequency welded pipe.
Process performance of high-frequency welded pipe: flattening, flaring, curling, bending, welding, etc.
High frequency welded pipe metallographic structure: low magnification structure (macro), high magnification structure (micro) M, B, P, F, A, S
Special requirements for high-frequency welded pipes: contract attachments and technical agreements.
High-frequency welded pipe inspection method:
First, chemical composition analysis: chemical analysis method, instrumental analysis method (infrared C-S instrument, direct reading spectrometer, zcP, etc.).
1. Infrared C-S meter: analyze ferroalloys, steelmaking raw materials, and C and S elements in steel.
2. Direct reading spectrometer: C, Si, Mn, P, S, Cr, Mo, Ni, Cn, A1, W, V, Ti, B, Nb, As, Sn, Sb, Pb, Bi
3. N-0 instrument: gas content analysis N, O
Second, the geometric dimensions and shape inspection of high-frequency welded pipes:
1. High-frequency welded pipe wall thickness inspection: micrometer, thickness gauge, no less than 8 points at both ends and recorded.
2. Inspection of the outer diameter and ovality of high-frequency welded pipes: calipers, vernier calipers, and ring gauges to detect large and small points.
3. High-frequency welded pipe length inspection: steel tape measure, manual, automatic length measurement.
4. High-frequency welded pipe bending inspection: ruler, level (1m), feeler gauge, thin wire to measure bending per meter, and full-length bending.
5. Check the end bevel angle and blunt edge of high-frequency welded pipes: square ruler and clamping plate.
Third, surface inspection of high-frequency welded pipes:
1. Manual visual inspection: lighting conditions, standards, experience, markings, high-frequency welded pipe rotation.
2. Non-destructive inspection: lighting conditions, standards, experience, markings, high-frequency welded pipe rotation.
3. Wave flaw detection UT: It is sensitive to surface and internal crack defects of uniform materials of various materials.
