The standard of Q235 is GB / T700. The standard of SS400 is JIS G3101. Comparison of chemical composition between Q235 and SS400: Q235B C: not more than 0.18, Mn: 0.35-0.80, Si: not more than 0.3 Q235B sulfur S: no more than 0.04, phosphorus P: no more than 0.04. SS400 sulfur S: not more than 0.05, phosphorus P: not more than 0.05. Comparison of mechanical properties between Q235 and SS400, plate steel A36: Q235 yield strength: not less than 185, tensile strength: 375-500, elongation: not less than 21. SS400 yield strength: not less than 215, tensile strength: 400-510, elongation: not less than 17.
The aging treatment of plate steel A36 steel plate: in order to eliminate the size and shape changes of precision measuring tools or molds and parts in long-term use, the workpiece is often reheated to 100℃ -150 ℃ and maintained for 5-20 hours before finishing at low temperature after tempering. This plate steel A36 process is called aging to stabilize the quality of precision parts.It is particularly important to aging steel members under low temperature or dynamic loading conditions to eliminate residual stress and stabilize steel structure and size.
Welded steel pipe refers to the steel pipe with a joint on the surface which is welded after the steel strip or steel plate is bent and deformed into circular, square and other expected shapes. According to different welding methods, it can be divided into arc welded pipe, high frequency or low frequency resistance welded pipe, gas welded pipe, furnace welded pipe, Bondi pipe, plate steel A36, etc. According to the weld shape, it can be divided into straight welded pipe and spiral welded pipe. Electric welded steel pipes are mainly used in oil drilling and production, machinery manufacturing, etc.; furnace welded pipes can be used as water gas pipes, large-diameter straight seam welded pipes for high-pressure oil-gas transmission, etc.; spiral welded pipes are used for oil-gas transmission, pipe piles, piers, etc. Welded steel pipe has lower cost and higher production efficiency than seamless steel pipe.
Facing the future, BBN Steel is willing to work with BHP Billiton to promote low-carbon metallurgy and recycling technology innovation and R&D deployment. Green raw materials are used to make green steel and contribute to the realization of green and low-carbon development of the steel industry chain and the building of a community with a shared future for mankind.
