Cold-rolled ribbed steel bars (GBl3788-1992)

The Cold Rolled Ribbed Steel Bars (GBl3788-1992)

Cold rolled ribbed steel bars, referred as steel bars for short, are mainly used in building constructions and reinforcing concrete structure. The type, specifications and standards of cold rolled ribbed steel bars can be found in industrial catalogues or related industrial standardization documents.

GBl3788-1992 is the national standard for requirements and design of cold rolled ribbed steel bars in China. It mainly refers to the production specifications and size dimensions of this special steel bar. According to GBl3788-1992 and its section 4, cold rolled ribbed steel bars must be produced through following steps.

The material used to manufacture the bars must be qualified carbon structural steel or other specified steel materials. Firstly, the steel material is cleaned and pickled upon arrival of the factory, in order to remove oil stains, such as mill scale, rust, and other impurities. Secondly, chemical composition test and other tests should be conducted on cleaned steel materials. Only the material with qualified analysis result can move on to the next stage of production.

The steel materials are next heated for hot rolling and then cooled for cold rolling. Being a cold formed ribbed steel bar, the steel bar is then shaped through a series of processes, ranging from cutting machinery to rolling machinery. And finally the ribbed steel bars get its surface treated. Chemical passivation via phosphating or galvanizing is used to protect the steel surface against oxidation and corrosion.

The quality of cold rolled ribbed steel bars must meet certain criteria. Such as the tensile strength of the bar, the elongation percentage, and the shape and size. In addition, after all production processes are done, the surface of the steel bars should be clean and be free from rust and other defects. All the quality requirements must be fulfilled before the steel bars leave the factory.

In conclusion, the standard GBl3788-1992 lays the foundation for the production of cold rolled ribbed steel bars in China, from material selection to quality control and other aspects. Manufacturers of ribbed steel bars must strictly follow this standard to produce qualified steel bars for construction projects.

介绍

Cold-rolled ribbed steel bars (GBl3788-1992)

Cold-rolled ribbed steel bars are produced according to GB/T 19378-1992. It is a kind of plain carbon steel that has been cold-formed into bars which are ribbed both in the center and on the edges. Specifically, the ribbed center portion provides greater elasticity and tensile strength of the steel bar, while the ribs on the edges increase the bonding area at the connection point between the steel bars and concrete. The ribbed steel bars produced by cold-rolling lead to higher strength, ductility and weldability in comparison to traditional steel bars.

Cold-rolled ribbed steel bars are primarily used for reinforced concrete and prestressed concrete structures, such as floor slabs, columns, beams, stadia, bridge decks and others. The ribbed steel bars also have been accepted for use in the steel framing of industrial and commercial buildings. They combine the strength of the steel with the security of the concrete for better resistance against external loads.

The cold-rolled ribbed steel bars produced by us meet and even exceed the quality requirements of GBl3788-1992. The size ranges from 6mm to 25mm and the length of the steel bars are usually 12m or 13m. Moreover, all the cold-rolled ribbed steel bars are now marked and finished to control the duration of the steel bars under proper storage. The reliable quality together with our fast and efficient service has won us clients all over the world.