Spiral pipe factory should be carried out before the mechanical properties test and flattening test, and the flaring test, to meet the standards. Straight seam steel quality inspection methods are as follows:
1, on the surface, that is visual inspection. Visual inspection of welded joints is a straightforward process, but widely used test methods are an important part of product testing with major defects and variations on the surface of the welded dimension. Usually with the naked eye, using standard models, gauges and test tools, such as magnifying glass. If the weld surface defects, weld defects may exist inside.
2, physical test methods: physical test method is to use some physical phenomena to test or test methods. Or in the workpiece material defect inspection, the general nondestructive testing methods. Non-destructive testing, radiation detection, penetration testing, magnetic testing.
3, pressure vessel strength test: pressure vessel, in addition to rigorous testing, but also for strength test. Common two kinds of hydraulic test and pressure test. They can be pressure vessel and pipe welding tightness test. Hydrostatic test is more sensitive than test speed, and the product is not treated with waste water after the test. The drainage problem is especially applicable to the product. But the risk is greater than the test pressure test. During testing, appropriate safety precautions must be followed to prevent accidents during the test.
4, compact test: liquid or gas tank welding, the weld is not dense defects, such as penetrating cracks, porosity, slag, incomplete penetration of loose tissue, etc., can be used for density testing. Compaction test methods are: kerosene test, water test, water hammer test.
5, hydrostatic test: each tube hydrostatic test should be done without leakage test pressure calculated P = second / DS - hydrostatic test stress test, hydraulic test stress test and the corresponding minimum specified level of steel standard (Q235 235mpa) the choice of 60%.
1. looks from the
spiral steel tube. The appearance is to pay attention to those welded joints. The appearance is not a defect and a lack of scale. This can be seen by the naked eye, of course detailed and bilateral theories, using standard models, measurement and magnifying glasses. Because of the appearance of welding defects, this means that the internal spiral tube is very likely to have defects, even if the effort in appearance is not completed, the internal effort is difficult to guarantee.
2. to see the method is to use the equipment to view, that is, without the risk of borrowing tube, ultrasonic flaw detection, ray flaw detection, penetration test and magnetic particle flaw detection method, can see the spiral tube no defect. In addition to the defective view, the strength of the pressurized container is also checked. There are usually two kinds of water pressure test and air pressure test. This view is to see the fineness of the weld of the spiral pipe, which is usually more accurate with the view of air pressure. But the pressure is very dangerous. If we don't carefully follow the rules, there will be a safety accident.
Spiral steel pipes also look through cracks, no pores, no mixed slag, no place without infiltration, is not a loose arrangement, usually oil test, water test or water test and other measures. In addition to doing water test, operation can ensure no leakage of piping.
