The shot blasting machine is not driven by compressed air, but by the mechanical and electrical shot blasting machine, which uses the high-speed shot blasted by the shot blasting machine to clean or strengthen the metal workpiece surface. Shot blasting machine can clean all kinds of residues on the surface of metal workpiece, and can also drop sand, remove core, clean casting, etc. shot blasting relies on the high-speed rotation of impeller. The abrasive in the center of the impeller is pre accelerated by the regulator and impeller propeller, sent to the blade area, and then thrown at high speed. Its speed can reach more than 100m / s. because of the large coverage of shot blasting, no air pressure is needed, and its energy efficiency is much higher than that of sand blasting. Impeller is the heart of shot blasting machine, driven directly or indirectly by motor. Each impeller manufacturer has unique design, mainly divided into single disc impeller and double disc impeller. Shot blasting machine is a casting equipment for cleaning or strengthening casting surface with high-speed shot blasted by shot blasting machine. The shot blasting machine can also drop sand, remove core and clean casting at the same time. In order to meet the requirements of surface treatment, the high-speed rotating impeller is mainly used to throw the granular sand out at high speed and hit the surface of parts.
Application scope of shot blasting machine
1. Cleaning of metal surface
When the blasting device was first used in the cast iron and steel industry, the surface bonded sand cast iron and oxide were removed. Almost all steel castings, gray castings, malleable castings, nodular cast iron, etc. shall be sandblasted. This not only can remove the surface oxide and cast sand, but also is necessary in the casting preparation process. For example, before the nondestructive test, the quality inspection of the large gas turbine shell must be carried out, and the shot blasting machine must be strictly carried out to ensure the reliability of the test results. Generally, in the production of castings, shot blasting machine found surface defects such as pinholes and tapped holes sand stick, low temperature compartment, a basic process from skin etc. in the device. Surface cleaning of non-ferrous metal castings, such as aluminum, copper alloy, etc., in addition to descaling, the more important purpose of the casting defect surface is to shoot the die-casting to remove the burr and obtain the comprehensive effect of significant decoration on the surface quality.
In metallurgical iron and steel production, shot peening and pickling is a mechanical chemical method to remove phosphorus skin, so as to ensure high productivity of large-scale production of iron and steel. In the production of silicon steel sheet, stainless steel sheet and other alloy steel sheets, annealing, shot peening and pickling must be carried out in the process of cold rolling to ensure the surface roughness and thickness accuracy of cold rolled steel sheets.
2 strengthening of metal workpiece
In modern metal strength theory, when the dislocation density of metal increases, the metal is increased
The main direction of power. Practice shows that shot blasting is an effective method to improve dislocation structure of metal. This is of great significance for some metals which can not be hardened by transformation (such as martensite quenching) or further strengthened on the basis of transformation hardening. Aircraft, aerospace, automobile, tractor and other parts have higher and higher requirements for lightweight, but also higher and higher requirements for reliability. Shot peening technology is an important technical measure to improve the strength and fatigue strength of components.
Shot peening and hardening application
Principle of shot blasting
The ball rotates at high speed by the impeller. The abrasive in the center of impeller will be accelerated in advance by the regulator and impeller, and sent to the blade area to throw abrasive at high speed. The speed can exceed 100M / s. Because of the large covering area of pellets, the energy efficiency is much higher than that of sandblasting without using air pressure.
Shot peening is a method to improve the fatigue strength of workpiece under high stress and alternating stress. Shot peening has replaced other time-consuming and expensive processes on a large scale, and can design components with lower cost and lighter weight. Shot peening plays an important role in improving the physical properties of workpieces.
