Screw thread steel Classification of

There are two common classification methods for deformed steel bars: one is to classify or type deformed steel bars according to the geometric shape, the cross section shape of the transverse rib and the spacing between ribs. For example, British Standard (BS4449) classifies deformed steel bars into Type I and Type II. This classification mainly reflects the grip performance of deformed steel bars. The second is based on performance classification (grade). For example, China's standard (GB1499) divides rebar into three grades according to strength grade (yield point/tensile strength); Japanese Industrial Standard (JISG3112) divides rebar into 5 categories according to comprehensive performance; British Standard (BS4461) also specifies several grades of rebar performance test. In addition, rebar can also be classified according to its use, such as ordinary rebar for reinforced concrete and heat treated rebar for reinforced concrete.

Hot rolled ribbed steel bars for reinforced concrete in China are made of HRB and the minimum yield point of the grade according to the national standard. H. R and B are the first letters of hot rolled, ribbed and bars respectively. Hot rolled ribbed bars are divided into three grades: HRB335 (old brand 20MnSi), HRB400 (old brand 20MnSiV, 20MnSiNb, 20Mnnti), and HRB500.

Use of deformed bar

Deformed steel bars are widely used in civil engineering construction of houses, bridges, roads, etc. From public facilities such as expressways, railways, bridges, culverts, tunnels, flood control, dams and so on, to foundations, beams, columns, walls, plates and deformed steel bars of housing construction, they are indispensable structural materials.

The construction industry, as one of the industries with large resource consumption, must adjust the consumption structure of building materials, vigorously apply high-strength steel bars and high-performance concrete, and take an economical development path in order to achieve sustainable development. If the reinforcement currently used is raised to a strength grade, the quantity of steel can be saved to a certain extent.

　　 wire rod Classification and application of

Classification of wire rod

With the development of industry, the application field of wire rod is more and more extensive, and the requirements for its variety and quality are increasingly strict and professional.

The steel types of wire rod are very wide, including carbon structural steel, spring steel, carbon tool steel, alloy structural steel, bearing steel, alloy tool steel, stainless steel, electric heating alloy steel, etc. The steel grades that need to be processed into wires are mostly produced into wire rods by hot rolling wire rod mills and then drawn into wires. Because of the variety of steel types and grades, wire rods are generally divided into the following four categories in the production of wire rods:

Flexible cord. It refers to ordinary low-carbon steel hot-rolled wire rod, and the grades are mainly Q195, Q215, HPB235 specified in the carbon structural steel standard and No. 10, 15, 20 steel specified in high-quality carbon structural steel.

Hard wire. It refers to the wire rod of high-quality carbon structural steel, such as wire rod for rope making wire, tire wire and other special wire rods. The carbon content of hard wire is generally high, generally referring to high-quality carbon structural steel above 45, 40Mn-70Mn, etc.

Solder wire. It refers to wire rod for welding rod.

Alloy steel wire rod. It refers to various alloy steels and special wire rods with high alloy content.

Use of wire rod

Wire rod is widely used. In addition to being directly used in buildings, it can also be processed into various special steel wires, such as spring steel wire, welding wire, galvanized wire, communication wire, steel cord, steel strand, etc; It can also be processed into other metal products, such as rivets, screws, nails, etc. At present, China is in the period of economic development. In addition to infrastructure construction and solving the residential conditions of residents still need a large number of wire rods for construction, the demand for metal products at home and abroad is increasing, and the number of wire rods for deep processing is also growing.