Inspection of Seamless Steel Pipe
Seamless steel tube is a very popular product in the international market. Because of its wide application and sales, it is difficult to guarantee the quality of seamless steel tubes. As a purchaser, first of all, the inspection items of seamless steel pipe should be defined. When purchasing seamless steel tubes, we can ask our suppliers to provide test results and test records.
As a regular seamless steel pipe supplier, to ensure the testing process and test results, to a certain extent, increase our cost, but also make our products to customer satisfaction.
Geometric dimension and shape inspection of seamless steel pipe/tube:
1. Inspection of groove angle and blunt edge of steel pipe end face: angle ruler and chuck.
2. Inspection of bending degree of steel pipe: Straight ruler, horizontal ruler (1m), plug ruler and thin line to measure bending degree per meter and full length bending degree.
3. Inspection of steel pipe length: steel tape, manual and automatic length measurement.
4. Inspection of outer diameter and ellipticity of steel pipe: caliper, vernier caliper and ring gauge, the maximum and minimum points are measured.
5. Inspection of steel tube wall thickness: micrometer and ultrasonic thickness gauge, with no less than 8 points at both ends recorded.
Chemical composition analysis: chemical analysis, instrumental analysis (infrared C-S instrument, direct reading spectrometer, zcP, etc.)
1.N-0 Instrument: Gas Content Analysis N, O
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 bulk samples
3. Infrared C-S instrument: analysis of ferroalloys, raw materials for steelmaking, C and S elements in steel.
Physical and chemical properties test of steel pipes:
1.Hardness test: Brinell hardness HB, Rockwell hardness HRC, Vickers hardness HV, etc.
2. Impact test: CVN, notch C, V, work J value J/cm2, standard sample 10 X 10 X 55 (mm) non-standard sample 5 X 10 X 55 (mm)
3. Tensile test: measuring stress and deformation, judging material strength (YS, TS) and plasticity index (A, Z), longitudinal, transverse section, arc, circular specimen (10, 12.5) diameter, thin-walled large diameter, thick-walled calibration distance.
4. Hydraulic test: test pressure, voltage stabilization time, p=2S delta/D
Surface Quality Inspection of Steel Pipe: 100%
1. Artificial naked eye inspection: lighting conditions, standards, experience, marking, steel pipe rotation.
2. Nondestructive testing:
A. Eddy current testing ET: (electromagnetic induction). It is mainly sensitive to point (hole) defects.
B. Ultrasound flaw detection UT: It is sensitive to surface and internal crack defects of materials with uniform materials.
C. Magnetic powder MT and magnetic leakage testing: magnetic testing, suitable for the detection of surface and near surface defects of ferromagnetic materials.
D. Electromagnetic ultrasonic flaw detection: It can be applied to high temperature, high speed and rough steel pipe surface without coupling medium.
E. Penetration inspection: fluorescence, coloring and inspection of surface defects of steel pipes.
