Pipeline geometry and external observation test:
Check wall thickness: micrometer, ultrasonic thickness gauge, both ends not less than 8:00 and record.
2 Pipe outer diameter, ellipticity inspection: caliper, vernier caliper, ring gauge, measuring maximum point, minimum point.
3 Pipe Length Inspection: Steel tape, manual, automatic length measurement.
4 Pipe Bending Inspection: Scale, Level (1m), Plug Scale, Measuring Fine Line Bending per meter, Full-length Bending.
Inspection of angle and blunt edge of end groove of steel pipe: square foot, chuck.




3. Surface Quality Inspection of Steel Pipe: 100%
Artificial visual inspection: lighting conditions, standards, experience, marking, steel pipe rotation.
2 NDE:
One. Ultrasound UT: It
It is sensitive to uniform surface and internal crack defects.
Standard: GB/T 5777-1996: C5
Bay Eddy Current Testing ET: (Electromagnetic Induction) Yes
It is mainly sensitive to point (cavity) defects. Standard: GB/T 7735-2004
Grade B
C. Magnetic powder MT and magnetic flux leakage detection:
Magnetic flaw detection is suitable for the detection of surface and near surface defects of ferromagnetic materials.
Standard: GB/T 12606-1999 Grade: C4 Grade
D. Electromagnetic ultrasonic flaw detection:
Without coupling medium, it can be applied to the surface inspection of high temperature and high speed thick steel pipe.
That is, penetration test:
Fluorescence, coloring and inspection of surface defects of steel pipes.




4. Steel tube performance test:
Tensile test: Measure stress and deformation, determine material strength (YS, TS) and plasticity index (A, Z)
Longitudinal, transverse sample tube segment, arc, circular sample (10, 12.5)
Small diameter, thin wall large diameter, thick wall fixed distance.
Note: The elongation after fracture is related to the sample size. GB / T 1760
2 Impact test: CVN, notch C, V, J/cm2 of workpiece
Standard sample 10 X 10 X 55 (mm) Non-standard sample 5 X 10 X 55 (mm)
Hardness test: Brinell hardness HB, Rockwell hardness HRC, Vickers hardness HV, etc.
4 Hydraulic test: test pressure, voltage regulation time, P = 2S delta/D.




5. Process performance test of steel pipe:
1 Flattening test: round sample C-shaped sample (S/D > 0.15) H = 1 + 2 S /(a + S / D)
L = 40-100mm deformation coefficient per unit length = 0.07-0.08
2-ring tension test: L = 15mm qualified without crack
Expanding and crimping tests: top taper 30, 40, 60.
Bending test: can replace flattening test (for large diameter pipelines)




6. Metallographic analysis of seamless steel pipe:
(1) High power detection (micro analysis) http://www.tjdwfgz.com metal inclusions 100x GB/T 10561 particle size: liquid level difference
Organization: M, B, S, T, P, F, AS
Decarbonization Layer: Internal and External
Method Rating: A-sulfide B-oxide C-silicate D-spherical oxides DS
2 Low magnification test (macro analysis): naked eye, magnifying glass less than 10x
One. Acid etching test, B. Sulphur printing test (tube blank test, showing low culture and defects, such as looseness, segregation, subcutaneous bubbles, peeling, white spots, inclusions, etc.)
C. Test method: Check the number, length and distribution of hairline