Shot blasting machine is a kind of processing technology that throws steel grit and steel shot on the surface of the material object at high speed, and uses the thrown high-speed shot to clean or strengthen the surface of the mechanical equipment. We are a professional shot blasting machine manufacturer in China, have kinds of industrial shot blasting equipments for sale, feel free to contact us.
What Is Shot Blasting Machine
Shot Blasting Machine is a surface preparation equipment that removes rust and oxide layer on the surface of the workpiece by steel shots or steel grits which thrown on the surface through high-speed rotating impellers. It is a machine for shot peening, cleaning metal parts such as forging, casting parts, steel surfaces, heavy metal structures, rusted metal parts, etc.
Shot blasting equipment not only can clean off contaminants like dirt or oil, remove metal oxides like rust or mill scale, but also can remove deburr the surface to make it smooth. Which will not change the shape of the workpiece, will not reduce the strength of the workpiece. Meanwhile, shot blasting machine can prepare a metal surface before the painting or coatings process, enhances the adhesion of the paint film and the material surface, increases the lifespan and the endurance of coating.
Blasting Machines
Shot blasting machine is the non-standard machine, also called customized blasting equipment, that can according to the shape, size and cleaning requirements of the different workpiece to choose different types shot blasting machine.
Roller conveyor shot blasting machine is the most common and environmentally friendly shot blasting machine. The machine is mainly used to clean steel plates, H beams, steel structures, steel pipes, steel channels, steel scaffoldings and other steel profiles.
Through the pretreatment of the steel profiles, to achieve the smooth surface. So as to enhance the adhesion of the paint film and the steel surface, thereby ensuring the quality of the steel anticorrosive coating.
Hanger type shot blasting machine is the most flexible and high-efficiency shot blasting machine. The machine operation easily, loading the workpiece on the hook then into blasting chamber to work. After a few times, all progress are completed. Hook type blasting machine is divided into single hook and double hook, hook type blast machine by two hook loading workpieces alternately into the blasting chamber.
Hanger type shot blasting machine mainly used in foundry, mechanism, chemical, motor, and other industries, to clean various of medium or large casting, forging, welding workpiece, including some fragile and irregularly shaped workpieces.
Mesh belt shot blasting machine used the mesh belt as the conveyor device. The machine can work continuously and in the progress of working have no collision. It suitable for small or medium workpiece and the production with large quantities.
The machine is a multi-functional shot blasting machine for cleaning dishes, flakes, castings, machine bodies, and structural parts, and it mainly used in automobile, aerospace, aluminum alloy industry and machinery manufacturing industries.
Overhead rail shot blasting machine is suitable for shot blasting large quantities of small and medium workpieces. The workpiece can run continuously or step by step along with the overhead rail conveyor system, so that the workpiece can be stopped in the loading and unloading area and the shot blasting area.
Compared with hanger type shot blasting machine, that with high production efficiency. The machine is the most ideal choice for automobiles, tractors, diesel engines, motors, valves and other industries.
Beams through type shot blasting machine is particularly suitable for long shape work-pieces such as profile, H beam, I beams, other construction parts.
- Cleaning
- Corrosion removal
- Remove welding slag
- Remove rust
- Paint Stripping
- Provides ideal surface finish (SA2.5-3.0) for securing a continuous and effective bond between the steel surface and coat.
Tumble belt shot blasting machine usually clean some small or medium workpiece. The belt is made of a circular space to let the workpiece roll in it and to achieve the purpose of cleaning. The machine suitable for sand removal, rust removal, descaling and appearance strengthening of small castings, forgings, stamping parts, gears, springs, etc.
It is especially suitable for cleaning and strengthening parts that are not afraid of collision and irregular shape workpiece. Tumble belt shot blasting machine is generally used in hardware manufacturing, die casting, precision casting and forging industries, etc.
Pavers type shot blasting machines are used for surface roughen and aesthetic appearance of marble, granite, concrete block and other stones.
QGMA is one of the earliest manufacturers which bring in stone shot blasting machines to China market. We have rich experience and have won lots of satisfaction from customers all over the world.
A endless rubber conveyor belt or roller conveyor transport work-pieces into blast chamber, after blasting process, extra cleaning units and high efficiency dust collecting units are available for customers’ requests.
Rotary table shot blasting machine is suitable for the cleaning of flat, thin-walled, sand-sticky oxide scale on the surface of parts that are afraid of collision in the casting and forging and heat treatment workshops.
It not only can remove the rust on the surface of the workpiece, but rust and dirt on various workpieces can also be cleaned, and the surface quality of the workpiece can be improved. This machine is widely used in steel, metallurgy, rolling stock, construction machinery, heavy mining machinery and other manufacturing industries.
Rotating drum or barrel shot blasting machine is suitable to blast work-pieces in batch, the work-piece keep mixing and tunbling under abrasive stream while the drum keeps rotating and tilting. Applications:
- Automative
- Iron, steel and metal foundries
- Heat treat operations
- Small stamping parts manufacturers
Steel plate shot blasting machines are specially designed for surface treatment to steel plates. Applications:
- Cleaning plate
- Corrosion removal
- Remove welding slag
- Remove rust
- Paint Stripping
- Provides ideal surface finish (SA2.5-3.0) for securing a continuous and effective bond between the steel surface and coat.
Pipe shot blasting machine is suitable for continuous shot blasting of the outer and inlet surface of batches of steel pipes before welding or painting to thoroughly remove rust, oxide scale and other dirt. After shot blasting, it can obtain a smooth surface with a certain roughness, increase spray adhesion, improve surface quality and anti-corrosion effect. The machine mainly used in some gas and oil industry, cylinder industry, shipbuilding and some other heavy industry.
Floor shot blaster is used to remove the coating on the floor, decontamination of nuclear power buildings; small-area steel surface cleaning; cross-street overpass coating cleaning; airport demarcation project; railway bridge deck waterproofing construction; highway bridge-tunnel pavement roughening. The machine can make the concrete surface uniform and rough, which greatly improves the adhesive strength of the waterproof layer and the concrete base layer.
Steel structure shot blasting machine is specially designed to clean all kinds of steel structure, the machine is designed with large dimension capacity to produce different work-pieces of all sizes. Applications:
- Cleaning
- Corrosion removal
- Remove welding slag
- Remove rust
- Paint Stripping
- Provides ideal surface finish (SA2.5-3.0) for securing a continuous and effective bond between the steel surface and coat.
Diabolo type shot blasitng machines are designed for descaling, derusting of steel cylinder, steel tube, pipe, round bar and all kinds of round work-pieces. Applications:
- Cleaning
- Corrosion removal
- Remove welding slag
- Remove rust
- Paint Stripping
- Provides ideal surface finish (SA2.5-3.0) for securing a continuous and effective bond between the steel surface and coat.
Bogie work car shot blasting machine is a fine solution for the treatment of middle and large size and heavy castings or forgings from 5 to 200 tons, such as
- marine engines
- energy and power generation components
- wind towers
- Removing of casting sand and filings, consolidating of the surface before coloring, etc.
Tunnel type shot blasting machines can process work-pieces like:
- Agricultural machinery parts
- Tower crane
- Large castings
- Heat-treated parts
- Truck chassis
- Large steel structure
- ect…
There are 2 main types of anchor chain shot blasting machines: vertical and horizontal, both can achieve a fine surface cleaning effect to chains with different dimensions. Main applications:
- Drive Chain
- Conveyor Chain
- Drag Chain
Blast Turbine
Blast turbines are the heart of shot blasting machine, as they represent one of the most important elements for its efficient operation. Blast wheels are made up of blades, control cage, distributor, impeller and guard plates. The abrasive enters distributor from silo by self-weight, then rotates in the blast turbines. The abrasive rotates to the window of the control cage, then thrown onto the workpiece along with the high-speed rotating blades.
How to choose different types of blades?
The blades have two kinds of types. The one is the same as its name, straight blades. The other one is the curve. If viewed from the side, the blades have a certain angle.
Compared with the same size of the straight blades, the biggest advantage of the curved blades is the higher grinding speed. So the energy shock transferred to the workpiece is greater.
Abrasive Recycle System
Abrasive recycle system is composed of a screw conveyor, bucket elevator, separator and storage hopper.
Bucket elevator lower part feeding gate is connected with screw conveyor, its upper part discharging gate is connected with separator. So the abrasive from screw conveyor into the bucket elevator, then transported by the bucket elevator to the separator on the top, and then the cleaned abrasive get into the storage hopper to recycle, the residue will get out of the recycling system from the separator system.
The separator is the most important part of the blasting machine, that determines the steel shot recycling rate. After into the separator, the steel shot and contaminants are uniform distributed in the separation chamber, presenting a flowing curtain. At this time, the separator fan absorbs air through the exhaust opening and separates the contaminants and steel shot by using the principle of gravity winnowing.
Dust Collector
In the shot blasting process of the shot blasting machine, the steel shot is projectile with a high speed, it will collide and friction with the workpiece. After passing through the recovery system, dust will be generated. The dust collector is to remove the dust in the blasting chamber and other devices to prevent air pollution.
The dust collector can be divided into three levels: coarse purification, medium purification, and fine purification according to the size of the collected dust particles. Coarse purification is to capture dust articles larger than 100 microns, medium purification is to capture dust particles of 10-100 microns, and fine purification is to capture dust particles of 10 microns.
The function of the dust collector is basically the same as that of the volumetric separator, but the structure is simpler. Its main function is to make the airflow to settle down the coarse particles in the airflow when it flows down in a roundabout way, so as to reduce the burden of the dust collector used in the second and third levels of dust removal and purification. The settling box is used for coarse purification, the second level dust collector is used for intermediate purification, and the third level dust collector is used for fine purification.
Test Standard of Shot Blaster
Rust removal grade and surface roughness are the important standards for testing whether the shot blasting machine is qualified.
The removal grade that can be achieved by shot blasting machine is SA2.5-SA3, which means after the shot blasting, the surface of steel without oil, oxide scale, rust and other contaminants, and the surface show a uniform metallic luster.
The surface roughness that can be achieved by shot blasting machine is 25-75μm, the influencing factors including blasting speed, blasting time, type and size of steel shot, etc…
Working Routine
- Dust collect system running
- Elevator running, separator running
- Screw conveyor running
- Workpiece transport system running, let the workpiece into blasting chamber.
- Blast wheels running
- Open abrasive supply valve, start work
- After the blast, close abrasive supply valve
- Blast wheel stop
- Workpiece transport system running, move out the chamber
- Continue to work, repeat step 4-9
- If stops working, please let the elevator stop, the separator stop, the dust collector stop, the whole machine stop.
Blast Machines’ Application Field
Shot blasting machine can perform sand dropping, core removal and cleaning on the casting at the same time. It can also be used for surface treatment of forged parts, aluminum-magnesium alloy parts, sheet welding parts, etc. Some areas are also known as blasters, sandblasters orally. It is faster and more effective than other surface treatment technologies, and it can be used for part-retaining or stamping after casting.
They can also be used to remove burrs, diaphragms, and rust, which may affect the integrity, appearance, or definition of parts of an object. The shot blasting machine can also remove surface contaminants on a partially coated surface, and provide a surface profile that increases the adhesion of the coating to achieve the purpose of strengthening the workpiece. Shot blasting machine is different in that it is used to reduce the fatigue life of parts, increase different surface stresses, increase the strength of parts, or prevent fretting.
Shot blasting machine is divided into drum type, chain plate type, rotary table type, trolley type, squirrel cage type and hanging type according to the structure of the casting carrier. It is mainly composed of blasting machine, shot blasting chamber and blower. It consists of scanning chamber, particle circulation system, dust removal system, guide roller, support roller, protection roller, sealing curtain and sealing roller.
Maintenance of Shot Blasting Machines
Daily Maintenance
- Check whether the bolts on the shot blasting machine and motor are loose, whether the wear-resistant parts in the shot blasting machine are worn and whether the access doors are closed.
- Check whether there is air leakage in the dedusting pipeline ,whether there is dust in the filter bag or whether there is debris on the filter screen in the separator.
- Check whether the electric control shot supply gate valve is closed and check the abrasion of the guard board in the shot blasting room.
- Check whether the limit switches are normal, whether the signal lights on the console are normal and clean the dust on the electrical control box.
Month Maintenance
- Check whether the bolts at the connection of each component are fixed.
- Check whether the rotating parts operate normally and lubricate them timely.
- Check whether the fan air duct is worn and fixed.
Quarterly Maintenance
- Check the intact condition of the bearing electric control box and fill it with lubricating oil.
- Check the wear of the abrasive blast guard of the shot blaster.
- Check the tightness of the bolts and flange connections of the motor, sprocket, fan, vibration transmission.
- Replace the bearings on the main bearing block of the shot blasting machine with new high-speed lubricants.
Annual Maintenance
- Check the condition of all bearings of the shot blasting machine and add lubricating oil, check the bag filter, check all motor bearings, replace or replace the guard board in the shooting area, and the machine shall be maintained regularly.
- Check the shot blasting cleaning indoor high manganese steel guard board, wear-resistant rubber and other guard boards, check the tension of the hoist, and timely tension when loosening.
- Check the vibration of the shot blasting machine, stop working immediately in case of any abnormality, and regularly lubricate all motors and bearings on the equipment.
- Add new projectiles regularly. When installing the blades of the shot blaster, the quality difference of a group of eight blades shall not be more than 5g, and check the abrasion of the blades.
How to Solve Common Problems
In the process of using shot blasting machine, we always have some problems, such as the dust collector with lower efficiency, the bucket elevator belt slippage, etc. Now QGMA Machinery will introduce some common problems and solutions to you, which can prolong the service life of the shot blasting machine.
Too much steel shot in dust collector
Reason: The separator air volume is too large.
Solution: Properly adjust the tuyere baffle until the dust removal effect can be ensured, but it is better not to suck out the projectiles.
Low dust efficiency of dust collector
Solution 1: The wiring of the dust collector fan is wrong, the fan is reversed and the wiring is re-wired;
Solution 2: The filter cartridge in the dust collector is not installed firmly or damaged or lacks the filter cartridge;
Solution 3: The joints of the dust removal pipes are not well sealed to ensure the sealing of all parts;
Solution 4: The cleaned work piece does not fall out as required, the molding sand remains too much and the dust content of the dust removal inlet is too high;
Solution 5: The back-blowing mechanism of the dust collector is not activated or the number of activations is small, the filter cartridge is blocked by dust and the dust attached to the filter cartridge is removed in time.
Bucket elevator does not operate
Reason 1: Clamp
Solution: Remove the oversized particles at the bottom of the elevator;
Reason 2: The belt slips.
Solution: Adjust the drive wheel tensioning device to tighten the belt;
Reason 3: There are too many shots at the bottom of the hoist.
Solution: Stop the machine in order and remove the shots.
The cleaning effect is not ideal
Reason 1: Insufficient supply of projectiles.
Solution: Add new projectiles appropriately;
Reason 2: The shooting direction of the shot blasting device is not accurate.
Solution: Adjust the window position of the directional sleeve of the shot blasting device;
Reason 3: The particle size of the steel shots is suitable.
Solution: The particle size of the steel shots is re-selected;
Reason 4: If the steel shots are agglomerated or used for too long.
Solution: Replace the steel shots.
The door of blasting room does not work or cannot be opened
Reason: The door shaft is not well lubricated.
Solution: Add lubricating oil.
The machine is not agile
Reason 1: Relevant electrical components are damaged.
Solution: Check and replace;
Reason 2: There is too much dust and dirt in the electrical box. The electrical contacts are in poor contact
Solution: Suggest to clean or replace.
Reason 3: Too much dust and dirt on the time relay.
Solution: Suggest to clean or replace.
Screw conveyor does not work
Reason 1: The steel shot are blocked.
Solution: Shut down in order and clear the pellets;
Reason 2: The spiral shaft is bent.
Solution: The outer diameter of the blade is corrected or polished;
Reason 3: The welding seam of the screw shaft head is broken
Solution: Re-welding.
Poor separation effect of separator
Reason 1: Uneven flow curtain.
Solution: Adjust the flow control panel to achieve full curtain;
Reason 2: The wind speed in the separation zone is suitable.
Solution: Adjust the butterfly valve of the separator tuyere to make the wind speed in the separation zone reach 4～5m/s, and adjust the position of the first and second regulating plates.
