3. Specifications and appearance quality
(1) according to GB14975-94 "stainless steel seamless pipe," provides that the length of pipe is usually (not cut to length) hot-rolled steel 1.5 ~ 10m, hot extruded pipe is equal to and greater than 1m. Cold drawn (rolled) pipe wall thickness 0.5 ~ 1.0mm persons, 1.0 ~ 7m; wall thickness greater than 1.0mm were, 1.5 ~ 8m.
(2) hot (hot extruded) tube diameter 54 ~ 480mm a total of 45 species; wall thickness of 4.5 ~ 45mm A total of 36 species.
Cold drawn (rolled) pipe diameter 6 ~ 200mm total of about 65 species; wall thickness of 0.5 ~ 21mm A total of 39 species.
(3) pipe external surface shall not have cracks, folding, crack, crack, rolling folding bed separation and scarring and defects exist, these shortcomings should be completely removed (except for mechanical processing pipe), after removal shall be held in wall thickness and diameter than plus or minus deviation.
Bills which do not exceed the allowable negative deviation of the other may from time to remove minor surface defects.
(4) straight to allow the depth. Hot-rolled, hot extruded steel pipe, 140mm diameter less than and equal to the nominal wall thickness of not more than 5% of the maximum depth of not more than 0.5mm; cold drawn (rolled) steel pipe is not more than 4% of the nominal wall thickness, maximum depth of not more than 0.3mm.
(5) The pipe ends should be cut at right angles and to be removed glitches. .

 

4. Chemical Composition Test
(1) according to GB14975-94 provision should be stainless steel pipe. Its chemical composition shall conform to GB1220-92 "stainless steel rod" and GB1221-92 "heat-resistant steel technical conditions."
(2) The chemical composition of the sample preparation according to GB222-84, chemical analysis in accordance with the relevant parts of GB223.
(3) The chemical composition of imports of stainless steel tube of indicators stipulated in the contract concerning inspection standards.
5. Physical performance test
(1) according to GB14975-94 requirements. Austenitic, austenitic - ferritic types of steel intergranular corrosion test to be done.
(2) tension test according to GB228-87, intergranular corrosion test according to GB4334.5-90, flattening test according to GB246-97, Flaring tested according to GB242-97, non-metallic inclusions according to GB10561-89, water pressure test according to GB / T241-90 regulations.
(3) The import of the physical performance test tube according to the criteria stipulated in the contract.
6. The main imports and exports
(1) Japan's imports of stainless steel pipe specifications are 323.9 �� 18mm; 18 �� 3mm �� 5 ~ 8m and so on.
(2) Italy imports of hot-rolled stainless steel pipe specifications are 273 �� 10mm �� 6m, steel grade TP321, the implementation of ASTMA312 standard, intergranular corrosion test according to ASTMA262E France.
7. Packaging
According to GB2102-88 "steel pipe inspection, packaging, marking and quality certificate of the General Provisions" implementation.