Selection criteria for boiler spraying materials

       1. Selection criteria for blasting materials



The sandblasting material is brown corundum, angular, Mohs hardness above 7, Al2O3 content above 90%, particle size 1.0 mm-3.0 mm, and quartz sand with particle size 1.0 mm-3.0 mm is screened before use, and fine particles below 1.0 mm are used. The powder content is not more than 5%, and no oil pollution is allowed. The moisture content is not more than 1%, preventing moisture, rain and impurities.

2. Selection criteria of spray wire

According to the analysis of the corrosion and wear mechanism of the water wall and the actual situation of your boiler, the anti-wear coating should meet the following requirements:



①The anti-corrosion material has sufficient corrosion resistance, and the wear-resistant material has sufficient coating hardness.



②A stable and dense oxide film can be formed on the surface at high temperature, which can resist the corrosion of harmful components such as sulfuric acid, nitric acid, hydrogen sulfide, sulfur dioxide, and alkali.



③High bonding strength, fully integrated with the base material to prevent falling off.



④The thermal expansion coefficient is close to the base metal to prevent peeling and cracking under alternating cold and hot conditions, such as heating or shutdown.



⑤ High thermal conductivity, does not affect the boiler heat collection.



3 Criteria for selection of sealing agent

It can be quickly cured at room temperature, has good air permeability, high temperature and wear resistance, high thermal conductivity, strong corrosion resistance, strong adsorption and thermal shock stability when it is bonded to the metal surface, no peeling, no cracking and other phenomena.