CNC Machining: Sandblasting Surface Finishing Process of CNC Machining Parts

What is sandblasting?

Sandblasting is a surface treatment process in which the dry sand stream is strongly sprayed onto the surface of metal CNC machined parts with purified compressed air to remove dirt. The compressed air is used as the power to form a high-speed spray beam to spray the spray material to the surface of the part to be processed at a high speed, so that the appearance or shape of the outer surface of the CNC machined part surface changes. Due to the impact and cutting effect of the abrasive on the surface of the workpiece, the The surface of the workpiece obtains a certain degree of cleanliness and different roughness, so that the mechanical properties of the surface of the CNC machined parts are improved, thus improving the corrosion resistance of the CNC machined parts, increasing the adhesion between it and the coating, and prolonging the The durability of the coating film is also conducive to the leveling and decoration of the coating.

The benefits of sandblasting the surface of CNC machined parts

(1) Improve the mechanical properties of CNC machined parts. After sandblasting, CNC machined parts can produce uniform and fine concave and convex surfaces on the surface of the parts, so that lubricating oil can be stored, thereby improving lubrication conditions and reducing noise to improve the use of CNC machined parts. life.

(2) Lighting effect For some special-purpose workpieces, sandblasting can achieve different reflection or matte at will.

(3) Cleaning and polishing of rough surface of castings and workpieces after heat treatment Sandblasting can clean all dirt (such as oxide scale, oil and other residues) on the surface of castings and forgings and workpieces after heat treatment, and polish the surface of CNC machined parts to improve the workpiece. The smoothness of the CNC machined parts can make the CNC machined parts show a uniform and consistent metal color, so that the CNC machined parts have a more beautiful appearance.

(4) Coating of CNC machined parts, sandblasting before bonding of CNC machined parts can remove all dirt such as scale on the surface of the workpiece, and can achieve different degrees of roughness by replacing abrasives with different particle sizes, which greatly improves the workpiece and coating. , the bonding force of the plating material; or make the bonding parts more firmly bonded and the quality is better.

(5) Burr cleaning and surface beautification sandblasting of CNC machined parts can clean up the tiny burrs on the surface of the workpiece, make the surface of CNC machined parts smoother, eliminate the harm of burrs, and improve the grade of the workpiece. At the same time, sandblasting can make small rounded corners at the junction of the surfaces of CNC machined parts, making CNC machined parts more beautiful and precise.

Materials and precautions for sandblasting of CNC machining parts

The sand used for sandblasting is generally quartz sand, or emery and steel shot (correspondingly called shot peening). The type and size of sand are selected according to the surface state and processing requirements of CNC machined parts. In order to prevent oil from contaminating the sand, contaminating the machined surface and blocking the nozzle, CNC machined parts with excessive oil on the surface should be degreasing and drying before sandblasting, and the compressed air sent to the sandblasting machine should also be filtered and purified. Pay attention to the pressure of the air because the pressure is large, the flow rate of the sand particles is large, and it is easy to be broken, which will affect the production capacity of sandblasting. The angle between the sand flow and the surface of the part being machined also has a great influence on the blasting effect.

How to prevent the clogging or damage of the teeth holes of CNC machining parts caused by sandblasting?

Before sandblasting, the protective screw plug is screwed into the threaded hole to prevent the high-speed sandblasting flow from damaging the internal thread during sandblasting; The inner thread of the threaded hole is protected from damage during processing.

If you encounter other surface treatment problems, you can contact us at any time. VMT has been focusing on high-demand, high-quality, high-quality surface treatment and texture precision CNC machining parts service manufacturers for 13 years.