The quality standards for steel bar is first certified for the quality standard of the kernel number; the surface, marked and indicated, is within the range of 5%, with a range of 5% overlapping use layers, the range of duties and deviations. If each unit is overlapping, the range and deviation are within the scope of duty. If each unit then 60% of each range is intercepted and two separate segments are intercepted to carry out and perform the inspection task and two separate segments are intercepted to carry out and inspection. 60 60 times, made in accordance with the use and testing example. The use shall be as required and requested. A specification is used in a manner that is direct or normative in accordance with its duties. It is divided into criteria and habits that are a flexible product face, whose criteria or use in accordance with the criteria are used to regulate the strict and criteria. Its classification criteria and standards, with direct criteria. The standard of specification, including the basic principles and basic principles. Standards and criteria with a straight stick in the delivery state.
The specifications contained therein include the standard number (type designation), the brand specification (gauge), the nominal specification (mass), the specified gauge length and the gauge specification value in the import and export trade.
Our standards recommend the lengths and lengths of the metric length diameters 6, 8, 1 for 12, 16, 20, 25, 3, 50, 3, 50. 6 to 12m long, Japanese rebar fixed length 3.5 to 10m; domestic rebar generally fixed length of 9m and 12m, such as the contract has not changed.
(1) Quality. The relevant standard specifies the surface quality of the surface section, requiring straight cut ends, no damage, scars or marks on the surface and no defects that are harmful to use.
(2) Permissible differences in external dimensions.
Standards For Steel GB14992079. Bar2-2-Steel Bars: Steel for Strict Use Part 2 Hot Rolled Strip Rules)
GB194.2-2007/XG1-2009 “Steel Bands for Strict Use Part 2: Standard Acceptance” National Standard No. 1 Revision; GB/T 2101-2008 (General Provisions for Type Steel Bands, Packaging Marking and Quality Certification)
GB14111.3 (49999); (JIS G3112-77) (JIS G3112-77 ) (to GB18 bar use 9); SG391-66 (for making); SG391-66 (shape, size and weight of hot-rolled and rolled steel and its and steel shape) ); (hot standard 97 for concrete structures)
(1) Test methods: The following standard test methods are commonly used for testing and analysing the above chemical composition: GB/T223, JISG1211?1215, BS1837, BS Manual 19, etc.
(2) Component indicators: The main indicators for assessing the content of rebar components are: C, Mn, P, S, Si, etc., with different grades and different contents.
There are differences between the grades and the content, the general range is: C (0.10-0.40%), Mn<1.80%, P<0.050 %, S<0.050%, Si (0.60-1.00%).
Rebar is widely used in the construction of houses, bridges, roads and other civil engineering projects. From highways, railways, bridges, culverts, tunnels, flood control, dams and other public facilities to the foundations, beams, columns, walls and slabs of buildings, rebar is an indispensable structural material. With the increasing urbanisation in China, there is a strong demand for rebar in the booming development of infrastructure construction and real estate.
When buying rebar, the first thing to do is to look at the external dimensions, using a vernier card gauge to simply measure whether the actual size is smaller than the stated size (generally the rebar is rolled with a specification mark) by about one specification or more (e.g. the standard internal diameter of a 12 rebar is 11.5±0.4mm
Secondly, the surface quality is poor due to the use of adobe, often with defects such as scars and an overall roughness. At the same time, some small rolling mills have a reddish surface colour due to insufficient heating temperature and rolling speed.
Most regular steel mills pack large bundles of steel from the factory, with the actual corresponding metal hangtags on the ladle, indicating the manufacturer, steel grade, batch number, specification and inspection code.
When purchasing rebar, it is advisable to go to a regular steel business or point of sale to obtain a steel quality certificate and have it inspected. If you are in doubt about the quality, go to a professional inspection agency for quality advice and testing.