2. The working principle of the suction dry sandblasting machine is that the compressed air is used as the power, and the abrasive is sucked into the spray gun through the sand conveying pipe through the negative pressure formed in the spray gun by the high-speed movement of the airflow, and then sprayed out through the nozzle to the machined surface, thus achieving the expected machining purpose. In the suction dry sandblasting machine, compressed air is not only the supply power of jet, but also the acceleration power of jet. For the press-in dry sandblasting machine, we mainly introduce the press-in sandblasting work unit, that is, the basic work unit composed of pressure tank and spray gun.
1. General ingredients
A complete press-in dry sandblasting machine generally consists of four systems, namely pressure box, medium power system, pipeline system and control system.
2. The working principle of press-in dry sandblasting machine.
Pressurized dry sandblasting machine is powered by compressed air. Through the working pressure established by compressed air in the pressure tank, the abrasive is pressed into the sand conveying pipe through the sand outlet valve and sprayed out through the nozzle to the machined surface, thus achieving the expected machining purpose. In the press-in dry sandblasting machine, compressed air is not only the supply power of the jet, but also the acceleration power of the jet. Compared with dry sandblasting machine, the biggest feature of liquid sandblasting machine is to control the dust pollution during sandblasting and improve the working environment of sandblasting operation. The structure and working principle of the liquid sandblasting machine will be introduced in detail below.
1. General ingredients
A complete liquid sandblasting machine generally consists of five systems, namely, structural system, medium power system, pipeline system, control system and auxiliary system.
2. Working principle
The liquid sandblasting machine uses grinding fluid as the supply power of grinding fluid, and delivers the evenly stirred grinding fluid (mixed fluid of abrasive and water) to the spray gun through the grinding fluid pump. As the accelerating power of grinding fluid, compressed air enters the spray gun through the gas pipeline. In the spray gun, compressed air accelerates the grinding fluid entering the spray gun and sprays it to the surface to be machined through the nozzle to achieve the expected machining purpose. In the liquid sandblasting machine, the grinding pump is the feeding power and the compressed air is the accelerating power.
Freezing sandblasting machine, full name is automatic spraying freezing trimmer. The theory of frozen sand blasting originated in Europe and America in 1970s, and was invented and improved by Showa Carbonic Acid Co., Ltd. of Japan. This equipment is mainly used to replace the manual deburring of rubber molded parts, precision injection molding and die casting products. This kind of equipment has been widely used in developed countries since the late 1970s, and has been gradually popularized in China since 2000, becoming one of the necessary post-processing equipment in rubber and plastic alloy industry. 1, simple operation: ordinary workers can operate the machine skillfully after half an hour of training, and advanced automatic control system can prevent workers from misoperation.
2. High production efficiency: the average daily processing capacity of a frozen sandblasting machine is equivalent to the sandblasting workload of 50-80 skilled workers.
3. High sandblasting accuracy: tiny and hidden flash can be removed, which is not limited by product shape, with high qualified rate and stable sandblasting quality.
4. Small rubber-plastic alloy products, brittle plastic products and magnesium alloy, zinc alloy and aluminum alloy castings with complex structures and arbitrary shapes can be removed.
5, the product surface is not damaged, the appearance quality of the product is improved, and the service life of the product is prolonged.
6. The floor space is small, and a frozen sand blasting machine and auxiliary equipment only need 10 square meter.
7. To reduce the use cost of the mold and the cost of rubber compound, the equipment does not need to tear the edge, but only requires that the flash should be as thin as possible below 0.2mm, and the overflow groove should be as small as possible. The flash margin is only1/5-1/kloc-0 of the edge-tearing mold.
8. Energy saving and environmental protection: the energy consumption of the machine is extremely low, and the discharged gas is nitrogen, the original component of air. Rubber-plastic alloy materials belong to polymer materials and will be in different phases at different temperatures. From the phase state, the material is only the change of mechanical state. When materials are at low temperature, their state changes, and when they return to normal temperature, their properties will recover.
The freezing sandblasting machine embrittles the rubber-plastic alloy material by using the low-temperature freezing effect of liquid nitrogen. At this point, the burr embrittles before the product. During the time difference when the raw edges are embrittled and the products are not embrittled, high-speed polymer particles are sprayed to impact the raw edges of the products, so that the raw edges of rubber-plastic alloy products and aluminum-zinc alloy products are removed, and the quality is high.
The physical properties of rubber-plastic alloy materials change with the decrease of temperature;
Hardening → embrittlement → vitrification
After the temperature drops, the rubber-plastic alloy material begins to harden and will not be deformed or damaged below the brittle temperature. Its physical and chemical properties will not change after returning to normal temperature. 1, host structure
It mainly includes: feeding system, circulation system, temperature control system and electric control system.
2. High-speed motor and projectile wheel
The vertical projectile spraying and freezing sandblasting machine must use high-performance motor components to ensure that it can drive the projectile to shoot at the highest speed of 7200 rpm, so as to knock off the raw edge of the product. Under high-speed operation, the dynamic balance error of the elastic wheel should not be higher than 3mm, otherwise the service life of the motor will be greatly reduced due to load operation.
3. Necessary auxiliary systems
OBD system: After testing by authoritative departments, the frozen sandblasting machine without OBD system can not guarantee to meet the national environmental protection requirements, but after dust removal with OBD system, it can guarantee to meet the national environmental protection standards. At the same time, OBD system can effectively prevent the moisture contained in the air from entering the equipment, and ensure the long-term stable operation of the equipment, thus prolonging the service life of the equipment. 1, high efficiency: a frozen sandblasting machine can handle the sandblasting amount equivalent to 80- 100 skilled workers on average every day.
2. Low cost: The use of frozen sand blasting machine can greatly reduce the production cost, such as saving sand blasting cost, management cost, raw material cost, mold cost, factory floor area, etc.
3. High quality: Freezing sandblasting machine can remove the burr of products perfectly according to production requirements, and can handle some special structures that cannot be handled manually without damaging the products.
4. Environmental protection: Freezing deburring is a physical method with no waste discharge and no pollution to the environment. Application field and scope of low temperature type
Applicable product materials: all kinds of rubber (including silica gel), injection molded parts, magnesium alloys, aluminum alloys, zinc alloys and other materials.
Applicable product industries: automobile, aerospace, computer, communication, home appliances and other 3C industries. At present, the most popular frozen shot blasting machine in the world is vertical shot blasting machine, and there are other horizontal shot blasting machines, but they are all outdated models and are gradually replaced by vertical shot blasting machines.
Conventional brands of vertical freeze sandblasting machines are:
Nisaki, polar shooting, etc. Among them, only Polar Jet is a brand authorized by Showa Carbonic Acid Co., Ltd. ..