Carbon structural steel Q235 is used to transport low pressure fluids

〣Introduction to carbon structural Steel Q235

This kind of steel is generally smelted by converter or open furnace, and its main raw material is molten iron and scrap steel. The content of sulfur and phosphorus in steel is higher than that of high-quality carbon structural steel, with sulfur ≤0.050% and phosphorus ≤0.045%. The content of other alloying elements, such as chromium, nickel and copper, brought into the steel by the raw material generally does not exceed 0.30%.International standard ISO: HR2(σs235).

〣Production technology

This kind of steel output is the largest, very wide use, more rolled into plate, profile (round, square, flat, work, groove, Angle, etc.) and profile and manufacturing welded steel pipe. Mainly used in building, bridge, ship and other building structure and general fluid pipeline. This kind of steel is generally not used directly after heat treatment.

Q235 steel pipe is used to transport low pressure fluid. General welding pipe Q195A, Q215A, Q235A steel manufacturing. It can also be made of other mild steels which are easy to weld. Water pressure, bending, flattening and other experiments should be carried out on the steel pipe, which has certain requirements on the surface quality. Usually, the delivery length is 4-10m, and the delivery length is usually fixed (or multiple) feet. The specification of the welded pipe is expressed by the nominal diameter (mm or inch). The nominal diameter is different from the actual diameter. The welded pipe has two kinds of ordinary steel pipe and thickened steel pipe according to the specified wall thickness, and the steel pipe has two kinds of thread and no thread according to the form of the pipe end.

Q235 steel pipe can be used for a variety of abrasive handles and other non-essential abrasive parts. Q235 steel is used as punch material, which is used directly after quenching without tempering, and the hardness is 36~40HRC, which solves the cracking phenomenon of punch in use.

〣National production Grade

GB700-88 standard carbon structural steel Q235 is divided into A, B, C, D four grades according to the metallurgical quality, the Si content of each grade of steel is 0.3%, the difference is the carbon content and sulfur, phosphorus content is different. The carbon content of Grade AB is 0.14%-0.22% and 0.12%-0.20%; the carbon content of grade CD is ≦0.18% and ≦0.17%; Grade A contains the least Mn and Grade D contains the least SP.

〣parameter