Circulating fluidized bed boiler is a kind of clean combustion technology boiler with high efficiency and low pollution developed in recent years. It has become the preferred equipment because of its wide adaptability of fuel, high combustion and desulfurization efficiency, good load regulation performance and easy comprehensive utilization of ash. However, because the water wall tube of this type of furnace works in the harsh environment of high temperature, solid erosion wear and flue gas corrosion, it is very easy to produce tube wall wear and high temperature corrosion, which makes the tube wall thin and even wear through the tube explosion. This not only seriously affects the safe operation of the boiler, but also causes huge economic losses. In order to solve the above problems, the supersonic arc spraying technology is used to spray a layer of metal alloy coating with wear resistance and high temperature corrosion resistance on the pipe wall, which can effectively protect the pipe wall from corrosion and wear, and effectively improve the service life of the equipment.

Advantages of supersonic arc spraying:

(1) The maintenance cost of the power plant is reduced (2) the economic benefit of the power plant is improved (3) the heavy maintenance labor intensity is greatly shortened, and the shutdown operation time is shortened.

Scope of application:

(1) It is suitable for "four tube" heating surface of coal-fired boiler (water wall tube, superheater tube, reheater tube and economizer tube) and blades of induced draft fan and coal exhauster with serious wear. Extend the service life of workpiece for 6-8 years.

(2) The long-term anti-corrosion of large steel structure can extend the service life of equipment for 25-30 years, such as large bridges, ships, iron towers, mine derricks, etc.

Technical features: the coating features high bonding strength, high hardness and high temperature corrosion resistance.

Bonding strength > 70MPa, hardness: HW ≥ 1000, HRC ≥ 70, porosity of coating < 1%. The oxidation resistance of the coating at 1100 ℃ is 20 times higher than that of No. 10 steel, and the erosion resistance of the coating does not decrease even at 1200 ℃.

             Water wall tube spraying                                    After spraying in dense phase area (1 year operation)

After spraying on the severely scoured parts              Before spraying                                       After spraying

Advanced equipment

            Lg-6.2/8 air compressor                         Dxt-20 spraying machine                   Supersonic arc spraying machine

            Spraying wire feeder                                       Spray gun head                            Super wear resistant alloy wire