Detailed analysis of the fire because of the following points:
1. The case of two rust dust flammable solids, which are low energy ignition and ignition. If the average particle diameter of rust dust in 100 ~ 150um, the ignition temperature in the range of 240-439 deg.] C, far below the melting temperature. Its combustible dust particle size, composition,
The concentration of a variety of factors, heat of combustion and combustion speed, etc., and the smaller the particle size, the greater the surface area, the more easily ignited. Fine dust generated during blasting, mainly composed of iron, iron oxides and dust, take the rust dust ignition test, is that is a, as in the fan air flow combustion, burning fast. Meanwhile filter cartridge filter material is usually paper or polyester fibers, which were mostly later, these two materials are flammable. Rust caused by flammable dust is on fire there are several possible scenarios, the source is usually caused by the fire burning hot particles, impact and friction sparks, sparks caused by static electricity.
2. External hot inhalation of dust. Resulting in fire external hot dust particles are inhaled, igniting internal rust dust, resulting combustible cartridge on fire, gas cutting and welding sparks Mars temperature generated by the number of Baidu reached, igniting dust rust easily. Shot blasting machine used in the impeller speed is typically n = 2250fmin, projectile speed is greater than 80m / s, high-speed steel shot hit the steel sheet may also produce sparks or hot particles is sucked into the dust caused by fire.
3. blasting machine cartridge inside temperature is high. Natural cause a fire into the steel temperature in the process of shot blasting machine generally controlled within 80 ℃, the single shot blasting machine total power usually in the tens to hundreds of kilowatts, of which most of the mechanical energy is converted into thermal energy in the production operation, the temperature of the system will be gradually increased. At the same time the material is converted to dust the surface area increase and improve the active substance in conditions with combustible, flammable dust exothermic oxidation rate than their cooling capacity, ultimately into the combustion dust called natural. The finer the dust, the easier it is natural. Rust dust of Fe, FeO, Fe20, Fe 0 at high temperature oxygen-rich environment will accelerate the oxidation of a large number of auto-ignition temperature oxidation heat , reached, which occurred burn itself out.
4. static electricity caused the fire. Rust dust in the high-speed air will produce static electricity. Due to natural radiation, ion or electron attachment, friction between dust particles and dust between objects or, usually causes dust particles with a charge. Rust dust flow in the pipeline, the self-friction, dust and piping, wall friction device can generate electrostatic potential of thousands of volts, while having such an electrostatic dust dispersion and suspension characteristics, dispersion increases friction area, suspension makes contact with rust particles, but not in a row, leading to increasingly high electrostatic potential. When the cumulative potential to increase the breakdown field of dust between the strong, it will generate static electricity spark, when the discharge energy to meet or exceed the minimum ignition energy of dust, rust, fire accident occurs. Tests showed chemical fiber filter is usually static where the most concentrated, the dust deposited on the cartridge to make room for the electric field intensity increases, when accumulated to a breakdown field strength between the dust, electrostatic spark discharge occurs, the discharge enough energy to ignite rust dust.
5. Another possible reason is itself shot blasting machine precipitator design is unreasonable, and this is no solution, only to find manufacturers to allow them to re-create a filter and own type of shot blasting machines supporting.
Fourth, shot blasting machine cartridges fire response
1. Repair of the fire source control. When subsequent shot blasting units inside and outside maintenance operations, strictly control the fire, to prevent ignition circuit, when gas welding work to be dismantled after 10 minutes dust around the maintenance job after Xu boot test or production, while throwing non-smoking unit near pill or other ignition, avoid sparks or hot particles is sucked into the dust collector.
2. The ground protection
 Related equipment and facilities to maintain good grounding, the grounding resistance requirements in the range of 1 ~ 4fZ, equipment and facilities to avoid the accumulation of static electricity; moreover increase the conductivity, instead of high insulating material with a conductor or a conductive material, in particular the use of the antistatic filter material.
3. Regular cleaning of rust and dust
 Prevent rust dust deposition, thermal accumulation, to promptly clean up dust fouling within the prescribed per shift should be carried out cleaning cinder.
 4. Raise awareness of the risks of the operation of the operation maintenance personnel, maintenance personnel training theory and practical knowledge to make staff aware of rust dust flammability, pay close attention to the health of cartridge filter in production.