The shot blasting and sand blasting are both methods of surface cleaning. Both of them have similarities and differences. We will explain the differences between the two below.
Shot blasting is to use a high-speed rotating impeller to throw small steel shots or small iron shots to hit the surface of the part at high speed, so the oxide layer on the part surface can be removed. At the same time, the steel shot or iron shot hit the surface of the parts at high speed, making the lattice distortion of the part surface and increasing the surface hardness. It is a method for cleaning the surface of the part. The shot blasting machine is often used to clean the surface of the casting or strengthen the surface of the part.
Generally, the shot blasting is used for regular shapes. Several shot heads are up and down, left and right together, with high efficiency and low pollution. In the ship repairing and the ship building industry, the shot blasting, and the sand blasting are both commonly used. However, whether it is shot blasting or sand blasting, the compressed air will always be used. It is dispensable to use a high-speed rotating impeller for shot blasting. Generally speaking, in the ship repairing and the shipbuilding industry, the shot blasting (small steel shot) is mostly used for pretreatment of steel plates (rust removal before painting); the sand blasting (it is the ore sand that is used in the ship repairing and the shipbuilding) is mostly used in forming ships or any other sections, and its role is to remove old paint and rust from the steel plate and repaint. In the ship repairing and the ship building industry, the main role of the shot blasting and the sand blasting is to increase the adhesion of steel plate coating paint. In fact, the cleaning of castings is not just by shot blasting. For large pieces, sandblasting is generally performed first. That is, the riser of the casting is cut off and placed in the drum. The parts collide with each other in the drum, and most of the sand on the surface should be removed first and then have the shot blasting or sand blasting.
Many studies have shown that, in terms of the destruction, tensile stress is much easier than compressive stress on the surface of metallic materials. When the surface is under compressive stress, the fatigue life of the material will be greatly improved. Therefore, for the parts that are prone to have fatigue fracture such as shafts will usually use shot blasting to generate surface compressive stress and increase product life. In addition, the mental materials are very sensitive to tensile, and that is why the tensile strength of the material is much lower than the compressive strength, and this is also why the general tensile strength (yield, pull-resistance) indicates the cause of material properties for the mental materials. The working surface of the steel plate of our daily car is strengthened by shot blasting, which can significantly improve the fatigue resistance of the material.
The shot blasting is to use an electric motor to drive the impeller body to rotate, relying on the effect of centrifugal force, throw balls with a diameter of 0.2 ~ 3.0 (including cast shot \ cut shot \ stainless steel shot, and so on) on the surface of the workpiece, so that the surface of the workpiece can have a certain roughness, making the workpiece more beautiful, or change the welding tensile stress of the workpiece to compressive stress, and improve the service life of the workpiece. It is almost used in most areas of machinery, shipbuilding \ auto parts \ aircraft parts \ the surface of gun or tank \ bridge \ steel structure \ glass \ steel plate \ pipe \ and so on. The sand blasting (pellet) is the use of compressed air as the power to spray shots with a diameter of 40 ~ 120 mesh or about 0.1 ~ 2.0 to the surface of the workpiece, so that the workpiece reaches the same effect. The treatment effect will be different, depending on the size of the pellet.
The sand blasting is a method of cleaning the surface of parts by blowing out quartz sand at a high speed, by using compressed air. It is also called sand blowing by some sandblasting room factory, which can not only remove rust, but also remove oil, and that is very useful for painting. It is often used for rust removal on the surface of parts; it is useful for the surface modification of small parts (the small wet sand blasting room sold on the market is used for this purpose, the sand is usually corundum and the medium is water); in the steel structures, the use of high-strength bolts for connection is a relatively advanced method, because the high-strength connection uses the friction between the bonding surfaces to transmit force, so the quality of the bonding surface will be very high. At this time, the bonding surface must be treated by sand blasting. The sandblasting room is used for situations where the shapes are complex, and when removing rust by hand, but the efficiency is low, the on-site environment is poor, and it is uneven to remove the rust.
The normal sand blasting rooms have a variety of blasting guns. As long as the box is not particularly small, you can put the gun in and clean it.
Qinggong Machinery has a wide range of shot blast machine and sandblasting equipment for sale, which can meet your requirements for different objects' surface treatment. Please contact us to get more information!