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What are the inspection items for ASTM standard seamless pipes? There are many quality inspection items for ASTM seamless steel pipes, mainly including physical and chemical properties, composition detection, size and process performance. This article takes the ASTM A450/A450M standard for steel pipes exported to the American standard as an example. Each requirement in this standard is activated by a total of 34 ASTM steel pipe standards, including ordinary seamless splicing and welded steel pipes, as well as American standard seamless pipes for steam boilers, ironmaking, sanitation, natural gas, and natural gas water supply pipelines. In the standard, each requirement is divided into mandatory and non-mandatory. Non-mandatory requirements are mainly inspected through agreements between supply and demand parties.

The mandatory requirements for American standard seamless pipes are: steel plant smelting analysis, furnace number and ingot composition; wall thickness is divided into seamless splicing hot finishing, seamless splicing cold finishing and welded steel pipes, the thickness deviation of the latter two is 0%, the dimensional tolerances of cold-processed and welded steel pipes are in the same order of magnitude, smaller than hot-processed steel pipes, size, iron pipe dimensional tolerance within 7.3m is within 5mm (partial 3mm), and other pipe dimensional tolerances are within 13mm; straightness and process performance, no burrs, etc., re-examination, the number of gold coin cards for the two groups of products is doubled; high-quality electrical testing laboratory, based on discussion, select UT, ET and MFT test methods.

Non-mandatory requirements, which need to be required in sequence: mechanical equipment chemical composition analysis, American standard seamless pipe, that is, American standard seamless pipe mechanical equipment chemical composition analysis; tensile properties, according to the elongation measured in the laboratory or the distance between the fracture positions, and the measured load; net weight, how many American standard seamless steel pipes are required, 4ln requires no less than 50 pipes, and below, 4ln requires more than 20 pipes, and above; deformation laboratory, seamless pipe and welded steel pipe sizes are 62mm and 100mm respectively, divided into two processes of ductility laboratory and data integrity laboratory, reverse deformation laboratory, welded steel pipe with a diameter of not less than 1/2ln, should be selected according to needs; combustion laboratory; laboratory curling; for resistance test, iron pipes with a wall thickness of less than 1.2 mm are not required to have this requirement, and welding of welded steel pipes should be avoided in resistance test, pressure test; in the underwater standard pressure laboratory, the lower standard pressure should be not less than 1MPa.
In addition, ASTM A106 American standard seamless pipe also discusses pipe end processing, while the Chinese standard generally specifies inspection items, sampling methods and other information in laboratory methods.