Angle bar is a kind of carbon structural steel used in construction, which is a simple section steel. It is required to have good weldability, plastic deformation and mechanical strength. The raw material for the production of angle bar billet is low carbon steel billet, finished angle bar for hot rolling, normalizing or hot-rolled state delivery.
2. types and specifications
It can be divided into two types: equilateral angle bar and non equilateral angle bar, of which the unequal angle bar can be divided into unequal thickness and unequal thickness of the same kind of two kinds.
The specification of angle bar with the length and thickness of the edge. At present, the domestic steel specifications for 2 – 20 cm, to length number number, the same horn steel often have 2 – 7 different edge thickness. The imported angle bar shall be marked on both sides of the actual size and thickness and indicate the relevant standards. Generally more than 12.5cm side of the large angle, 12.5cm – 5cm between the medium angle, the side length of 5cm for the small angle.
Inlet and outlet angle bar orders to use commonly required in the specification, the steel is carbon steel steel corresponding. That is, in addition to the specifications of the angle, there is no specific composition and performance series.
The length of the angle of the length of the fixed length, two times the size of the domestic angle of the fixed length of the choice of different sizes according to the specifications of the different – 9m, 4 – 12M, – 19m, 6 – 19m range of four -. The length of Japanese steel angle is 6 – 15m.
The cross section of unequal angle bar is calculated by the long side width of unequal angle bar.
3. import and export situation
China’s imports and exports have a certain amount of angle, mainly from Japan, Western Europe imports. Exports to the region mainly for Hong Kong, Macao, Southeast Asia, Latin America and Arabia countries. Export production enterprises mainly in Liaoning, Hebei, Beijing, Shanghai, Tianjin and other provinces and cities of the iron and steel plant (rolling mill).
Most of the imported angle bars are large and small angle bar and special shape angle bar, and most of them are medium angle bar, such as No. 6 and No. 7.
4. appearance quality requirements
The surface quality of the angle bar is stipulated in the standard, and the general requirements for the use of harmful defects such as delamination, scarring, cracks, etc..
The allowable range of the geometric deviation of angle bar is also stipulated in the standard, including the bending degree, the width, the thickness, the vertex angle, the theoretical weight and so on.
5. chemical composition test
(1) composition index: the chemical composition of angle bar is a series of rolled steel series for general structure, and the main indexes are C, Mn, P, S and four. According to the different grades, the content of each difference, the approximate range of C 0.22%, Mn:0.30 – 0.65%, P < 0.060%, S < 0.060%.
(2) test method: detection of the chemical composition, test methods commonly used standard GB223, JISG1211, BS1837, BS – 1215, 19 F C, manual is 22536.
6. commonly used products, specifications and standards
GB/T2101 – 89 (General requirements of steel acceptance, packing, marking and quality certification); GB9787 – 88/GB9788 – 88 (hot rolled / unequal angle size, shape, weight and tolerances); JISG3192 94 (shape, size, and weight of hot rolled steel tolerance; DIN17100 – 80 (mass) standard steel structure; it is common), 535 – 88 f (technical conditions of ordinary carbon steel).
According to the standard requirements, the angle should be a bundle of delivery, the bundle passes, bundle length should be specified. Angle is generally a bare delivery, transportation and storage should pay attention to moisture.
7. mechanical properties test
(1) inspection methods:
Tensile test method. Method for inspection of commonly used standard GB/T228-87, JISZ2201, JISZ2241, ASTMA370, BS18, C, f is 1497 and DIN50145; bending test method. Method for inspection of commonly used standard GB/T232-88, JISZ2204, JISZ2248, ASTME290, F, C and DIN50111 is 14019.
(2) performance indicators: the inspection of the performance of the angle of the main tensile test and bending test. The indexes include yield point, tensile strength, elongation and bending compliance.
Source: China Angle Bar Manufacturer – Yaang Pipe Industry Co., Limited (www.yaang.com)