Guangzhou Steel teach you: steel works, steel selection General rules
1, steel orders, its variety, standard and functions should be in line with the existing national planning documents and steel specification given.
2, steel purchase contract response data trademarks, standard size, function parameters, check requests, size deviation clear agreement. Length of steel should be left margin retest samples; delivery status of steel, according to planning documents should be the function of the steel and supply manufacturers agreed to a request. Guangzhou Steel
3, the outer appearance inspection of steel, shall comply with the rules of this specification, there should be consistent with existing national norms "Steel Construction Quality Acceptance" GB 50205 of the relevant rules. Attributed to one of the following conditions of the steel, should be sampled retest:
1) foreign steel imports;
2) mixed batch of steel;
3) thickness equal to or greater than 40mm, and is planning to have a feature request planks Z;
4) building structural safety grade level, large span steel structure, the main force of the steel components used;
5) Plan are steel reinspection request;
6) any doubt on the quality of steel.
4, the content of steel retest should include mechanical functional test and chemical analysis.
5, when the planning documents no special request, steel construction steel sample used trademark retest inspection batch should perform the following rules:
1) trademark Q235, Q345 and has a thickness of less than 40mm of steel, should be the same manufacturer, the same trademark, same quality grade steel material inspection batches of components should not be greater than 150t; the same manufacturer, the same mark for steel Beyond 600t cargo weight and retest all when passing each batch Batch component expandable 400t;
2) trademarks for Q235, Q345 and has a thickness greater than or equal to 40mm steel, should be the same manufacturer, the same trademark, same quality grade steel material inspection batches of components should not be more than 60t; the same manufacturer, the same trademark Steel supply components and full time beyond 600t retest qualified, each batch Batch component expandable 400t;
3) the trademark Q390 steel, should be the same manufacturer, same quality grades of steel constitute examine batches of components should not be more than 60t; steel component supplier of the same manufacturer 600t and beyond when full retest qualified, each batch The group expanded to grant component 300t;
4) the trademark Q235GJ, Q345GJ, Q390GJ steel, should be the same manufacturer, the same trademark, same quality grade steel material inspection batches of components should not be more than 60t; the same manufacturer, supplier of steel components of the same trademark beyond 600t and retest qualified full time, each batch Batch component expandable to 300t;
5) trademark for Q420, Q460, Q420GJ, Q460GJ steel, each inspection should be granted the same trademark, same quality grade steel the same heat, the same thickness, the same delivery status configuration, batch weight should not be greater than 60t;
6) in the thickness direction of the plate requests, should additional ultrasonic nondestructive testing by one retest.
6, sampling, sample preparation and test methods for steel imports reinspection shall planning documents and contractual rules execution. Customs inspection result after supervising engineer recognized as useful information retest results. Guangzhou Steel