The technical requirements for various stainless steel pipe fittings are clearly specified in various standards or technical agreements. Different working conditions and uses have different technical requirements for steel fittings. It mainly includes the following contents:

(1) Varieties and specifications. It specifies the sectional shape, size, allowable deviation, theoretical review, etc. of stainless steel pipe fittings. The specification of round pipe is usually represented by DxS, for example, 50mmx2mm indicates that the outer diameter of stainless steel pipe fittings is 50mm and the wall thickness is 2mm. The dimensional accuracy includes wall thickness accuracy, outer diameter accuracy and ovality.

(2) Surface quality requirements. Specify the internal and external surface status of stainless steel pipe fittings and the extent of allowable surface defects.

(3) Chemical properties. Specify the chemical composition of the steel, the maximum content of P and S and the test method.

(4) Microstructure and physical properties: specify the metallographic structure, mechanical properties and process properties of the steel grade.

(5) Inspection standards. Specify inspection items, sampling parts, sample shape and size, test conditions and methods, etc. In addition to routine test items, some process performance tests are sometimes required in the production of stainless steel pipe fittings.