The technical requirements for various stainless steel pipe fittings are clearly stipulated in various standards or technical agreements. Different working conditions and uses have different technical requirements for steel symbols. mainly includes:
(1) Various specifications. The cross-sectional shape, size, allowable deviation, theoretical review, etc. of stainless steel pipe fittings should be specified. The pipe specification is usually expressed by the source DxS. For example, 50mmx2Mm means that the outer diameter of the stainless steel pipe is 50 Mm and the wall thickness is 2Mm. The dimensional accuracy includes wall thickness accuracy, outer diameter accuracy and ellipse.
(2) Surface quality requirements. Specify the internal and external surface conditions of stainless steel pipe fittings and the degree of allowable surface defects.
(3) Chemical properties. It specifies the chemical composition of steel and the maximum content of phosphorus and sulfur as well as test methods.
(4) Organization and physical properties: specifies the metallographic structure, mechanical properties and technological properties of the steel seed chamber.
(5) Inspection standards. Specify inspection items, sampling components, sample shape and size, test conditions and response methods, etc. In the production of stainless steel pipe fittings, in addition to conventional test items, some process performance tests are sometimes required.
