Shot Blast Media

The world's first shot blasting machine was born in the United States. The shot blasting machine refers to the casting equipment that uses the high-speed abrasive thrown by the blast turbines to clean or strengthen the surface of the casting. The shot blasting machine can de-core and clean the workpiece at the same time. In the process of shot blasting, some shot blast media is needed. Let me show you today.

1. What is Shot Blasting Process?

First, let's introduce the working principle and workflow of the shot blasting machine. When the shot blasting machine starts to work, the workpiece is transported on the transportation system. Different types of shot blasting machines have different transportation methods, such as roller conveyor systems, v-wheel conveyor systems, hook conveyor systems, and others. When the workpiece into the blasting chamber, the blast turbines start to work.

The blast turbines use a high-speed rotating impeller to project steel grits in a certain direction under the action of centrifugal force. Each impeller with 8 blades, with the distributor and control cage formed a complete impeller body.

The cover is lined with a guard plate, and the cover is equipped with a control cage and an abrasive inlet pipe. Inlet pipe flows into the blast turbine, and the distributor that rotates synchronously with the blade makes the steel grit get the initial speed. Steel grit flies out through the window of the control cage and is thrown onto the high-speed rotating blade outside the control cage. After being further accelerated by the blade, it is projected to on the surface of the workpiece to be cleaned, because the distributor and the blade rotate synchronously, Vibration-free transmission of the steel grit to the blade is ensured, thereby reducing the wear on the blade. Then talk about the abrasive recovery system. The abrasive falls into the screw conveyor. The screw conveyor transports the abrasive to the bucket elevator, and then to the separator on the top. The separator separates the recyclable abrasive into the abrasive silo. Unusable abrasives and some large particles of impurities that fell during the cleaning process are transported to the waste abrasive hopper and discharged through the pipe. Finally, Is the dust collector system, because, in the shot blasting machine process, there will be some from the cleaning workpiece the dust generated at the time,  dust needs to be processed. At this time, the fan of our dust collector starts to work. Dust is absorbed to the cartridge filter of the dust collector through the pipe connected to the blasting chamber, and the dust on the cartridge filter is blown back by pulse. It is blown into the dust bag at the bottom. At this time, the whole shot blasting process has ended.

2. What Material is Used for Shot Blasting?

There are many types of abrasive used as shot blasting material, such as cast steel shots, cut steel wire shots, alloy steel shots, steel grit, stainless steel shots, and strengthened steel shots. Steel grit is divided into GP, GH, and steel shot is also divided into S110 and S330. S460, S780, and other models have different hardness and are suitable for different workpieces.

2.1 Steel wire cut shot

Steel wire cut shots, also known as wire-cut shots, cut shots, and wire cut sections, are cylindrical particles with a certain proportion of length cut from scrap steel wires of various specifications. The steel wire cutting shot has high hardness, is not easy to deform, and has high impact resistance. It is used for the cleaning and strengthening of the shot blasting machine. The service life of cut steel wire shot is about 5 times longer than that of cast iron shot, and it is more economical to use.

Steel wire cut shots are widely used in machinery, chemical equipment, ships, containers, automobiles, light industry and other manufacturing industries.

2.2 Strengthened steel shot

A strengthened steel shot is refined by wire drawing, cutting, strengthening, and other processes. The particle size of the product ranges from 0.2mm to 2.5mm and the shape is cylindrical G1, G2, G3, and the service life is 3500 to 9600 cycles.

A strengthened steel shot has stronger toughness and is not easy to break, so it has a long life and strong impact resistance. It can reach the shot blasting strength in a faster and shorter time, and can maintain the shot blasting strength for a better and longer time; more consumption during use low, strengthened steel shot service life is 3-4 times longer than that of ordinary specifications. Strengthened steel shots can bring a higher quality of shot blasting cleaning and significantly improve the cleaning efficiency. Taking conventional spring cleaning and gear cleaning as examples, the use of reinforced steel shot cleaning can improve the efficiency compared with ordinary high-carbon steel shots. More than 50%, compared with ordinary high steel shot, Dust emission is reduced by at least 30%, which reduces the compliance of the dust removal system, extends the service life of the dust collector, and reduces the pollution to the environment. It is a real green steel shot.

Strengthened steel shots are mainly used in the metal surface treatment fields of aerospace, national defense, military industry, nuclear industry, wind power industry, automobiles, motorcycles, shipbuilding, transmissions, spring industries, and other industries.

2.3 Stainless steel shot

Stainless steel shot is made of stainless steel wire through drawing, cutting, rounding and other processes. There is no rust on the surface, no acidification, and the service life is 3-5 times that of carbonized steel shot, which is economical and environmentally friendly. After cleaning, the surface defects of the product can be eliminated to highlight the metal color. It makes the product surface smooth, bright and has a matt effect. It does not require pickling and rust removal. It meets environmental protection requirements. It is a non-polluting shot blasting material. wear resistance is 3-5 times that of cast steel shots, which can reduce production. cost.

This product is widely used in large, medium and small castings, steel plate pretreatment, engineering machinery, stainless steel plate cleaning, pipeline anti-corrosion and other industries for descaling, rust prevention, etching, and enhanced shot blasting.

2.4 Zinc shot

Zinc shot is mainly used for deburring and cleaning various aluminum and zinc pressure castings, deburring of various products, peeling and cleaning of various coatings. It can effectively deburr the surface of ferrous metal and non-ferrous metal parts, polish the non-ferrous metal parts and finish the main surface of the parts.

Pure zinc shots are widely used in automobiles, airplanes, shipbuilding, containers, machinery manufacturing, metal casting, metal surface treatment, and other industries. The products are known as beauticians on metal surfaces.

2.5 Cast steel shot

Cast steel shots, also called alloy steel shots, are made by atomizing or granulating molten steel into spherical particles, and after subsequent multiple heat treatments, mechanical treatments and screening, the finished product is finally obtained. Cast steel shot has great economic benefits, has good toughness, high strength, does not break, and can reduce blade wear and improve the cleaning quality of the shot blasting machine. It has the advantages of polishing, rust-removing and grinding for the processed workpieces, no pickling, and rust-removing treatment is required, and high wear resistance, which can reduce production costs.

It is widely used in the surface spraying and polishing pretreatment of various steel such as steel structure, container, machinery manufacturing, and shipbuilding industries before coating.

2.6 Steel grit

Steel grit is commonly known as cast steel grit abrasive. Different types of cast steel grit products will be used in different processes. They are applicable to the industrial range. Cast steel grit is made of high-quality steel scraps. First, it is melted, and then the molten steel is formed by high-pressure water jetting. Small spherical.  Formed pellets are heated again to purify and homogenize and then quenched. The quenched pellets are dried in the furnace and reheated and tempered to achieve the appropriate hardness. Tempered alloy steel pellets are sorted into 11 grades that meet the SAE standard through a mechanical screen for use in shot blasting equipment.  Products of different particle size and hardness are used in different processes, such as surface strengthening.

Cast steel grit is widely used for descaling and rust removal of steel workpieces before coating. In this case, centrifugal shot blasting equipment is often used.

2.7 Aluminum shot

Aluminum shots are refined with aluminum wire, cutting, grinding and other processes. Appearance is bright and cylindrical. Aluminum shots are used for surface treatment of non-ferrous metals and stainless steel products. Aluminum shots are used in conjunction with stainless steel shots. The processed workpieces can achieve matte whitening, smooth effects. After use, there is no need for pickling treatment to highlight the metal Natural color, with good applicability and safety. The aluminum shot is applied to the surface of aluminum, zinc or thin-walled workpieces.

3. Shot Blasting Equipment

There are many types of shot blasting machines, the workpieces to be processed, and the processing speeds are also different. Next, I will introduce several common shot blasting machines.

3.1 Tumble belt shot blasting machine

Used for cleaning and strengthening of castings and forgings, small round springs, bearings, and other workpieces. Tumble belt shot blasting machine is general equipment, the main models are QG326 tumble belt shot blasting machine, QG3210 shot blasting machine.

3.2 Hook type shot blasting machine

It is mainly suitable for the surface treatment of various medium and large castings, forgings, weldments and heat-treated parts, including fragile and irregularly shaped workpieces. The general equipment models of hook type shot blasting machine, Is QG376 single (double) hook type shot blasting machine, and QG378 single (double) hook type shot blasting machine. This type of shot blasting machine can also be designed and manufactured according to the parameters of the workpiece specifications provided by the customer.

3.3 Rotary table shot blasting machine

It is suitable for cleaning flat workpieces that are afraid of collision. Put the workpiece on the rotary table, and the abrasives are hit vertically to the surface of the workpiece, which can achieve the purpose of shot blasting. Rotary shot blast machine is a piece of general equipment.

3.4 Tunnel type shot blasting machine

The tunnel type shot blasting machine is used to clean large structural parts and castings with a single piece weight of more than 2 tons, such as the boom of excavators, sticks, and tower cranes in the construction industry. This type of machine has high efficiency and good effect characteristics.

3.5 Overhead rail shot blasting machine

Overhead rail shot blasting machine is suitable for shot blasting of small iron castings, steel castings, forgings and stamping parts, to remove sticky sand, rust, oxide scale and dirt on the surface of the workpiece to make the surface of the workpiece appear metallic, eliminate the internal stress of the workpiece, improve the fatigue resistance of the workpiece, increase the adhesion of the paint film when the workpiece is painted to improve the surface and inner quality of the workpiece.

3.6 roller conveyor shot blasting machine

It is a multifunctional shot blasting equipment for cleaning structural parts, H-shaped steel, steel plate and other types of steel. There are two types of flat roller conveyor and V-shaped roller conveyor. It can apply strong shot blasting to the surface of the steel in its original state to remove its rust spots, welding slag and oxide layer. In order to eliminate stress, improve the quality and corrosion resistance of steel structure and stell surface coating. This machine is suitable for stress relief and surface rust removal of steel plates, section steels, steel pipes, metal structural weldments, steel products, railway vehicles, engineering machinery, bridge manufacturing, etc. It is the most widely used shot blasting machine.

3.7 wire mesh shot blasting machine

The wire mesh shot blasting machine is mainly used for surface shot blasting of thin-walled castings, thin-walled and fragile iron or aluminum alloy castings and other small parts. It can also be used for shot blasting strengthening of mechanical parts. It has the characteristics of good continuity, high cleaning efficiency, small deformation, no pits, etc. It can be used alone or as a part of the line.

3.8 Steel plate/profile shot blasting and painting line

Process of steel shot blasting and painting line refers to the process in which steel is shot blasted to remove rust and coated with a protective primer before processing (that is, the state of the raw material). The pretreatment of steel can improve the corrosion resistance of mechanical products and metal components, improve the fatigue resistance of the steel plate, and prolong its service life; at the same time, it can also optimize the production state of the steel surface, which is conducive to CNC cutting machine blanking and precision blanking. In addition, because the steel shape is relatively regular before processing, it is conducive to mechanical rust removal and automatic paint spraying. Therefore, using the steel shot blasting and painting line can greatly improve the efficiency of the cleaning work and reduce the labor intensity of the cleaning work and the pollution to the environment.