Industrial Q235B straight seam welded steel pipe details

Production method: SAW double-sided submerged arc welded steel pipe, ERW high-frequency resistance welded steel pipe
Product execution standards: GB/T3091 welded steel pipe for low-pressure fluid transportation, GB/T13793 straight seam electric welded steel pipe.
Product specifications: outer diameter 10mm~2060mm, wall thickness: 1mm~100mm.
Chemical composition: Carbon: 0. 12~0. 20% Manganese: 0. 30~0. 670 Silicon: ≤0.30 Sulfur: ≤0.045 Phosphorus: ≤0.045
Tensile strength: 375MPa~500MPa

Usual length The usual length of electric resistance welded (ERW) steel pipe is 4000㎡m~12000mm. The usual length of submerged arc welded (SAW) steel pipe is 3000 mm~12000㎡m. The fixed length of the fixed-length steel pipe should be within the normal length range, and its allowable deviation is "2mm. The double-length length of the steel pipe should be within the normal length range, and its allowable deviation is *" mm. Each multiple-length length should be left 5mm~10mm incision allowance.

Steel pipes with a nominal outer diameter of curvature not exceeding 168.3㎡m shall be straight for use, or the curvature index shall be specified by agreement between the supplier and the buyer. For steel pipes with a nominal outer diameter greater than 168.3mm, the bending degree should not be greater than 0.2% of the total length of the steel pipe. The two end surfaces of the steel pipe at the pipe end should be perpendicular to the axis of the steel pipe, and there should be no cut burrs. For steel pipes with an outer diameter greater than 168.3m, the incision slope should not be greater than 5㎡. According to the requirements of the buyer, upon agreement between the supplier and the buyer, and specified in the contract, the end of the steel pipe with a wall thickness greater than 4" can be processed with a bevel angle of The remaining thickness at the 30° pipe end is 1.6. The bending test shall be carried out for resistance welded steel pipes with a nominal outer diameter not greater than 60.8. There shall be no filler during the bending test. The bending radius of the ungalvanized steel pipe shall be 6 times the nominal outer diameter. The bending radius of the galvanized steel pipe is 8 times the nominal outer diameter, the bending angle is 90°, and the weld is located on the side of the bending direction. There should be no cracks on the sample after the test. The zinc layer of the galvanized steel pipe should not peel off.

Flattening test Resistance welded steel pipes with a nominal outer diameter not larger than 0.3㎡m shall undergo a flattening test. For electric resistance welded steel pipes with a nominal outer diameter not greater than 168.3, when the distance between the two pressure plates is 3/4 of the nominal outer diameter of the steel pipe, there should be no cracks in the weld; when the distance between the two pressure plates is 3/5 of the nominal outer diameter, there should be no cracks in other parts other than the weld; for resistance welded steel pipes with a nominal outer diameter greater than 168.3m, when the distance between the two pressing plates is 2/3 of the nominal outer diameter of the steel pipe, there should be no cracks in the weld; When the distance between the flat plates is 1/3 of the nominal outer diameter of the steel pipe, there should be no cracks in other parts other than the weld. Hydraulic test steel pipes shall be subjected to hydraulic tests one by one, and the test pressure shall comply with the requirements in Table 6. The pressure stabilization time of steel pipes with a nominal outer diameter less than 508㎡m should not be less than 5s; the pressure stabilization time of steel pipes with a nominal outer diameter not less than 508m2 should not be less than 10s. Under the test pressure, the steel pipes should not leak. Manufacturers can also use eddy current testing or ultrasonic testing instead of hydraulic testing. The eddy current flaw detection of steel pipes was carried out by the relevant provisions of GB/T 11345. The artificial defects (drilling holes) of the comparison samples were grade A. The ultrasonic flaw detection was carried out by the relevant provisions of GB/T 11345. The inspection grade was grade A and the assessment grade was grade three. The arbitration shall be based on the hydraulic test.