First, the steel in large, medium and small division

Large

Medium

Small

I-beam high ≥ 180mm high <180mm

Channel height ≥ 180mm high <180mm

Equilateral angle edge width ≥ 160mm edge width 50-140mm edge width 20-45mm

Uneven angle steel edge width ≥160 & # 215; 100mm edge width 140 & # 215; 90-50 & # 215; 32mm edge width & lt; 45 & # 215; 28mm

Round steel diameter ≥ 90mm diameter 38-80mm diameter 10-36 mm

Square steel edge width ≥ 90mm Edge width 50-75 mm Edge width 10-25 mm

Flat steel width ≥120mm width 60-100mm width 12-55 mm

Rebar diameter ≥40 mm Diameter 10-36 mm

Rivet steel diameter 10-22 mm

Other profiled steel: profiled steel such as crawler plate and steel sheet pile, profiled steel such as compound flat steel for small-scale farmers, tool steel, window frame steel, etc.

Second, hot-rolled ribbed steel

1. Variety specifications

Hot-rolled ribbed steel grades by HRB and grades of the minimum yield point form. H, R and B are the first letters of the alphabet of Hotrolled, Ribbed, and Bars respectively. Hot-rolled ribbed bar is divided into HRB335 (old grade 20MnSi), HRB400 (old grade 20MnSiV, 20MnSiNb, 20MnTi), HRB500 three grades.

2. Vanadium Ⅲ thread steel

① Prospect of vanadium-containing grade Ⅲ rebar market Vanadium-containing grade III rebar (20MnSiV, 400Mpa) is added with vanadium, niobium and titanium alloy during the production process. Compared with ordinary grade Ⅱ rebar, it has the advantages of high strength and toughness Good, good welding performance and shock resistance. In Europe and other developed countries, the construction market, Ⅲ grade rebar accounted for 80% of the total rebar, such as Britain, Germany, Australia, ** and other countries use high-strength grade III steel rebar has reached 80-90%. In 1995, the Ministry of Metallurgy and Ministry of Construction jointly issued a document to promote the use of the Ministry of Construction of the new grade Ⅲ rebar into the national standard technical conditions GBJ10-89 "Concrete Structure Design Code", since January 1, 1997 into effect, the new Grade Ⅲ rebar has been successfully applied in high-rise buildings, large-scale power stations, bridges, tunnels, airports and other projects. The market prospect is broad. Ministry of Construction requirements in 2002 the amount of new grade Ⅲ rebar to reach 50% of the total rebar, "Tenth Five-Year" to reach 80% at the end. However, due to publicity, promotion efforts are not enough, the amount is still significantly lower than the old grade II 335Mpa ordinary grade rebar, so the new grade III rebar also need to vigorously promote and promote.

② The advantages of the reinforced bar containing vanadium Ⅲ level

A. Economy: Due to high strength, the use of new grade III rebar can save 10-15% of the steel compared with grade II rebar, thus reducing the construction cost of construction.

B, high strength, good toughness: micro-alloying treatment, the yield point of 400Mpa above, the tensile strength of 570Mpa above, respectively, than the Ⅱ grade reinforced rebar increased by 20%.

C, Seismic: Vanadium-containing steel bars have higher bending, aging properties, higher low-cycle fatigue properties, the seismic performance was significantly better than Ⅱ-level rebar.

D, easy welding: As the carbon content of ≤ 0.54%, good welding performance, to adapt to a variety of welding methods, the process is simple and convenient.

E, the construction is convenient: Adopt the new grade III rebar to increase the construction clearance, has provided the guarantee for the construction convenience and the construction quality.

Third, hot-rolled H-beam

1. Hot-rolled H-beam representation.

H-beam is divided into wide flange H-beam (HK), narrow flange H-beam (HZ) and H-beam pile (HU) three categories. The method is expressed as follows: Height H & # 215; Width B & # 215; web thickness t1 & # 215; wing thickness t2 as shown in Q235, SS400200 & 200; # 8 & # 215; Width 200mm web thickness 8mm, wing thickness 12mm wide flange H beam, its grade is Q235 or SS400.

2. The advantages of hot-rolled H-beam H-beam is a new type of economic construction steel.

H section steel is economical and reasonable in cross-sectional shape and has good mechanical properties. The points on the cross section of the H-beam are extended uniformly and the internal stress is small. Compared with ordinary I-beam, H beam has the advantages of large section modulus, light weight and metal saving, Structure to reduce 30-40%; and because of its parallel to the inside and outside the legs, leg ends are right angles, assembled into components, saving welding, riveting workload up to 25%. Commonly used in large-scale buildings (such as factories, high-rise buildings, etc.) that require large bearing capacity and good cross-sectional stability, as well as bridges, ships, hoisting and transporting machinery, equipment foundations, brackets and foundation piles.

Fourth, cold-formed steel

Cold-formed steel is an economic section of light-weight thin-walled steel, also known as steel cold-formed or cold-formed profiles. It is made of hot-rolled or cold-rolled strip as a blank by bending the various cross-sectional shape and size of steel. Cold-formed steel has the following characteristics:

1. cross-section economy and reasonable, save material. Cold-formed steel cross-sectional shape can be designed according to needs, reasonable structure, the unit weight of the cross-section coefficient higher than the hot-rolled steel. In the same load, can reduce the weight of components, saving materials. Cold-formed steel structure for the construction of hot-rolled steel can save 38-50% of the metal, for agricultural machinery and vehicles can save 15-60% of the metal. Easy construction, reduce the overall cost.

2. Variety, can produce the general hot-rolled method is difficult to produce uniform thickness, cross-sectional shape of the various sections and a variety of different shapes of cold-formed steel.

3. Products smooth surface, good appearance, precise size, and the length can also be flexibly adjusted according to need, all according to the length or double supply, improve material utilization.

4. Production can also be punched and other processes to meet different needs.

Cold-formed steel variety, from the cross-sectional shape, with openings, semi-closed and closed mouth, the main products are cold-formed channel, angle steel, Z steel, cold-formed corrugated steel, rectangular pipe, welded steel pipe, shutter doors Wait. Cold-formed steel usually produced below 6mm in thickness and below 500mm in width. Products are widely used in mining, construction, agricultural machinery, transportation, bridges, petrochemicals, light industry, electronics and other industries.

Zhangjiagang Xiaofeng building materials mainly produces cold-formed profiles in Shanghai, Jiangsu.