Sandblasting - an environmentally friendly industrial surface treatment process

Sandblast Definition: The process of cleaning and roughening the surface of the substrate using the impact of high-speed sand flow.

First, the general composition:

A complete inhalation dry sandblasting machine generally consists of six systems, namely, structural system, medium, power system, piping system, dust removal system, control system and auxiliary system.

Second, the working principle:

Sand blasting is powered by compressed air to form a high-speed jet beam. Spray material (ore sand, glass sand, quartz sand, corundum, iron sand, Hainan sand, plastic sand, and plant sand) is jetted at high speed to the surface of the workpiece to be processed, making the workpiece The appearance or shape of the outer surface of the surface changes. Due to the impact of the abrasive on the surface of the workpiece and the cutting action, the surface of the workpiece is given a certain degree of cleanliness and roughness, so that the mechanical properties of the workpiece surface are improved, thus improving the workpiece The fatigue resistance increases the adhesion between it and the coating, prolongs the durability of the coating, and also facilitates the leveling and decoration of the coating.

Third, the main application of sandblasting:

(1) Before workpiece coating and workpiece bonding, sandblasting can remove all the dirt such as scale on the surface of the workpiece, and establish a very important basic pattern on the surface of the workpiece (which is usually called a rough surface). Through the exchange of abrasives with different particle sizes, for example, the abrasives of the flying abrasive abrasives reach different degrees of roughness, which greatly improves the binding force between the workpiece and the coating and the plating material. Or make the adhesive bond more firm and better quality.

(2) Cleaning and polishing sandblasting of the matte surface of the casting and the heat-treated workpiece can clean up any dirt (such as scales, oil and other residues) on the surface of the workpiece after heat treatment, and polish the workpiece surface to improve the finish of the workpiece. , Can make the workpiece exposed uniform metal color, so that the appearance of the workpiece is more beautiful and beautiful.

(3) The burr cleaning and surface beautification of the machined parts can clean up the tiny burrs on the surface of the workpiece and make the surface of the workpiece smoother, eliminating the danger of burrs and improving the grade of the workpiece. And sandblasting can make a small round at the interface of the workpiece surface, making the workpiece more beautiful and more precise.

(D) to improve the mechanical properties of the parts After the mechanical parts by sandblasting, the surface of the parts can produce uniform and fine concave and convex surface, so that the lubricating oil is stored, so that the lubrication conditions improve, and reduce noise and improve mechanical life.

(5) Polishing effect For some special-purpose workpieces, sandblasting can be used to achieve different reflective or matte finishes. Such as stainless steel workpieces, plastic grinding, polishing jade, wooden furniture surface matt, frosted glass surface pattern, as well as the fabric surface of the wool processing.

Fourth, the safety operation regulations:

Sandblasting machine is a modern, high-efficiency, low-cost, cost-effective cleaning equipment. Sandblasting machines are commonly used for the surface derusting of erosive materials or workpieces, and the de-oxidation of non-rusted metals, and the cleaning of surface soils. , product enhancement, beautification, stress removal and other application areas, in the daily work, sandblasting machine operating procedures are directly related to the safety of production.

Fifth, sandblast safety operating procedures:

1. Must wear protective equipment before work, no naked arm work, holding certificates;

2. The blasting work is finished in each shift and workers need to clean the spilled abrasive.

3. Regularly check the system's connection ports are good, to ensure the sealing performance of the compressed air pipeline. If there is a leak, it needs to be maintained in time (this work is done once a month);

4. Regularly check the performance of consumables such as spray guns and sand tubes, and replace them if they are damaged (this work is performed once a week);

5. The electrical control cabinet should be isolated from the work area;

6. The compressed air valve should be opened slowly and the air pressure should be maintained at 0.8MPa.

7. Sandblasting particle size should be compatible with the work requirements, sand (abrasive) should be kept dry;

8. When the sand blaster is working, it is forbidden to get close to the unrelated person. When cleaning and adjusting the operating position, it should be stopped;

9. It is forbidden to blow dust or joke on the body with a spray gun.

10. After the work is completed, the ventilation and dust removal equipment should continue to operate for five minutes before closing to remove indoor dust and keep the site clean.

11. Occurrence of personal and equipment accidents shall be maintained on site and reported to relevant departments.

Failure Analysis: Sandblasting machine is a common cleaning machine. With the wide application of sandblasting machines, operators who are troubled by some sandblasting machines will not be able to continue using the sandblasting machine if they do not eliminate the trouble in time.

Sixth, the common sandblasting machine failures The main possible causes: Failure phenomenon There is no compressed air, no abrasive 1. The compressed air is not open 2. The pressure regulating valve sets the pressure too low 3. The switch is not adjusted or damaged 4. Blasting or abrasive Valve blockage 5. Safety air path is cut off 6. The main pressure regulating valve of the blasting machine is broken 7. The pressure regulating valve for control is broken 7. Remedy 1. Open the air source 2. Adjust the pressure to 0.5 MPa or more 3. Adjust Or replace the switch. 4. Clean the nozzle or abrasive valve or reinstall. 5. Check the valve on the safety valve. 6. Check the main valve of the sandblasting machine. 7. Check the sandblast control valve. Detailed answer!