The operation method of epoxy resin coated steel bar

Epoxy resin coated steel bar is a kind of steel bar with a protective layer of epoxy resin film on the surface of ordinary steel bar, and the thickness of the coating is generally 0.15mm~0.30mm.

The use of this epoxy-coated steel bar can effectively prevent the steel bar from being corroded under harsh environmental conditions, thereby greatly improving the durability of the engineering structure.

Most of the epoxy-coated steel bars are currently used in reinforced concrete structures, and the construction technology is not complicated. According to the pilot project and foreign application experience, the construction team of general quality can be competent after the disclosure.

The use of epoxy-coated steel bars in structures in corrosive environments has enormous economic and social benefits. The difference is that epoxy-coated steel bars are stronger and more resistant to corrosion than ordinary steel bars.

Epoxy-coated steel bar production: Unlike the usual epoxy resin coating on the surface of the steel bar, the epoxy resin-coated steel bar is made by electrostatic powder spraying, and the surface of the steel bar is coated in the factory.

The United States has successively tested 56 kinds of coating materials, and finally selected this thermosetting electrostatic spray epoxy powder coating material and production process.

Adhesion and influence on concrete grip: The unique properties of epoxy resin powder and the electrostatic spraying process can ensure good adhesion between the coating and the base steel bar, good tensile and bending resistance, short radius 180° bending, Still no cracks appear, which is difficult to achieve with other coatings.

It is important that the reduction of the grip strength of epoxy resin coated steel bars and concrete is the smallest (relevant standards allow a reduction of 10%), while other coatings may greatly reduce the grip strength (even more than 50%) (my country's standard). It is stipulated that the surface of the steel bar cannot be coated with a coating, etc., also because the general coating can significantly reduce the gripping force between the steel bar and the concrete).

The epoxy resin powder coating also has the following properties: a. Alkali resistance. It can withstand the high alkaline environment of concrete for a long time (pH=12.5～13.5); b. Chemical resistance.

Because epoxy resin powder coating has high chemical stability and corrosion resistance, and the film layer is impermeable, it can prevent water, oxygen, chloride and other corrosive media from contacting steel bars; c. Elasticity and friction resistance are all good.

Epoxy Coated Rebars have many advantages and advantages, and as a new technology, they have been rapidly developed abroad. However, problems and deficiencies have also been found in use, leading to engineering accidents.

In addition to the quality of the project, it was also found that the epoxy-coated steel bars had quality problems and problems in the use process. The main problem was whether the integrity of the epoxy coating on the surface of the steel bars could be guaranteed.