Classification and use of steel

Steel classification: The product types of construction steel are generally divided into rebar, wire, disk screw, round steel.

1. round steel:

Round steel is a long, solid steel bar with a round cross-section. Its specifications are expressed in millimeters of diameter, such as 50, which means round steel with a diameter of 50 mm.

Round steel material: 10#, 20#, 35#, 45#, 304, 316, 20Cr, 40Cr, 20CrMo, 35CrMo, 42CrMo, 40CrNiMo, GCr15, 65Mn, 50Mn, 50Cr, 3Cr2W8V, 20CrMnTi, 5CrMnMo, etc.

Round steel is divided into hot rolled, forged and cold drawn three kinds. Hot rolled round steel is 5.5-250 mm in size. Among them: 5.5-25 mm small round steel is mostly supplied in straight strips in bundles, commonly used as steel bars, bolts and various mechanical parts; Round steel larger than 25 mm, mainly used for the manufacture of mechanical parts or seamless steel blanks.

The role of construction steel:

Rebar is widely used in various building structures.

2. wire:

Usually involved more specifications are 6.5mm, 8.0mm, 10mm (diameter); In addition, there are 5.5mm, 6.0mm, 7.0mm and so on. At present, the maximum diameter of wire rod produced in China can reach 30mm. In addition, the general allowable tolerance for wire production is 0.4mm.

Common grades of wire generally divided into Q195, Q215, Q235 three kinds, of which construction steel wire rod only Q215, Q235 two grades; For example: Q235 (Q- refers to the yield strength of steel, 235 refers to the yield strength is not less than 235Mpa).

According to the rolling speed, the wire can be divided into: general line, high line and quasi-high line

3. Disc screw:

Construction steel, as the name suggests, is like wire plate together rebar, the general market is 6.5-8.0-10-12-14 majority.

Disc screw advantages: the steel bar is only 9-12, and the disc screw can be intercepted at will according to demand.

4. steel bar:

The specification range of rebar is generally 6-50mm, and we usually involve more 8mm, 10mm, 12mm, 14mm, 16mm, 18mm, 20mm, 22mm, 25mm, 28mm, 32mm, 36mm, 40mm and so on. The deviation allowed by the country: 6-12mm deviation in 7%, 14-20mm deviation in 5%, 22-50mm deviation in 4%.

Rebar is generally fixed length 9m, 12m, of which 9m long thread is mainly used for normal road construction, 12m long thread is mainly used for bridge construction.

Rebar can be divided into three categories according to strength: HRB335, HRB400, HRB500 three categories.