Chemical properties of high-frequency welded pipes: room temperature mechanical properties, high-temperature mechanical properties, low-temperature properties, and corrosion resistance. The physical and chemical properties of high-frequency welded pipes mainly depend on the chemical composition of steel, the organizational structure and purity of steel, and the heat treatment method of high-frequency welded pipes.
Process performance of high-frequency welded pipes: flattening, flaring, curling, bending, welding, etc.
Metallurgical structure of high-frequency welded pipes: low-magnification structure (macro), high-magnification structure (micro) M, B, P, F, A, S
Special requirements for high-frequency welded pipes: contract attachments, technical agreements.
Inspection methods for high-frequency welded pipes:
First, chemical composition analysis: chemical analysis method, instrumental analysis method (infrared C-S instrument, direct reading spectrometer, zcP, etc.).
1. Infrared C-S instrument: 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 in block samples
3. N-0 instrument: gas content analysis N, O
Second, high-frequency welded pipe geometric dimensions and appearance inspection:
1. High-frequency welded pipe wall thickness inspection: micrometer, thickness gauge, no less than 8 points at both ends, and record.
2. High-frequency welded pipe outer diameter and ovality inspection: caliper, vernier caliper, ring gauge, measure large and small points.
3. High-frequency welded pipe length inspection: steel tape measure, manual and automatic length measurement.
4. High-frequency welded pipe curvature inspection: ruler, level ruler (1m), feeler gauge, fine wire to measure curvature per meter and full-length curvature.
5. High-frequency welded pipe end face groove angle and blunt edge inspection: angle ruler, card plate
Third, high-frequency welded pipe surface inspection: 100%
1. Manual visual inspection: lighting conditions, standards, experience, identification, high-frequency welded pipe rotation.
2. Nondestructive testing inspection: lighting conditions, standards, experience, identification, 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.
Post time: Sep-02-2024