How does each part of the shot blasting machine works

Shot blasting machine function

1. Remove the rust layer, welding slag, and oxide scale on the surface of the workpiece to obtain a uniform metallic luster.

2. The surface produces a certain degree of unevenness, increases the surface density, increases the friction coefficient of the components and the adhesion of the coating, so as to improve the coating quality and anti-corrosion effect of the steel.

The working principle of shot blasting machine

1. The working principle of the wheel blast

Wheel blast is the main part of shot blasting machine accessories it is composed of impeller, blades, abrasive distributor, control cage, spindle, and other spare parts.

The steel shot flows from the funnel into the abrasive distributor by its own weight, and the abrasive distributor that rotates at the same speed as the main shaft rotates around the steel shot. Under the action of centrifugal force, the steel shot is pressed to the inside of the control cage. When the steel shot reaches the opening of the control cage, it will be thrown out from the opening. It is received by the high-speed rotating blade and accelerates from the inside to the outside along the blade. At a speed of 60~80m/s, it is thrown towards the workpiece to be cleaned in a fan shape, so that the surface of the workpiece can be shot blasted Adjusting the position of the opening of the control cage can change the direction of the steel shot so that the thrown iron shot is projected to the workpiece to be cleaned as much as possible. The incorrect position of the control cage not only reduces the efficiency of shot blasting process but also increases the abrasion of the arc-shaped guard plate. The size of the outlet of the control cage will affect the spread angle of the steel shot (the angle between the sectors). The larger the outlet, the larger the spread angle, and the worse the cleaning effect. Therefore, after the opening of the control cage is worn, it needs to be adjusted in time. When the amount of wear exceeds 15 mm, it needs to be replaced.

The main parameters that affect the cleaning efficiency of the wheel blast are the ejection speed and shot blasting volume of the steel shot. The higher the ejection speed, the greater the impact force; the increase in the amount of shot blasting per unit time, the greater the concentration of steel shots on the unit area of the tool to be cleaned. The effect of increasing the ejection speed and distance. After the steel shot is thrown from the wheel blast, the speed will gradually decrease due to the resistance of the air during the movement. Under normal circumstances, the kinetic energy loss of the steel shot increases by about 10% for every additional meter of the projectile distance. Generally, the distance between the surface of the workpiece to be cleaned and the centerline of the wheel blast is preferably 0.7~1.5m. If it is too close, the shot mark of the steel shot will be too deep and the projectile area will be too small, and if it is too far, the cleaning effect will be reduced.

working principle of the wheel blast

2. The working principle of the separator.

The mixture of steel shot and impurities flowing in from the bucket elevator is sent to the upper part of the air-wash zone by the screw conveyor at the bottom, and the screw at the bottom makes it uniformly transported along with the separator over the full length of the separation zone, forming a waterfall-like steel Pills and impurities flow curtain. At the same time, the dust collector fan draws air through the tuyere of the separator, and uses gravity winnowing to effectively separate the steel shots, molding sand, metal oxide fragments, broken steel shots, and dust in the flow screen, and then flow into the silo after secondary filtration by the bottom screen. Store and enter the next step of recycling.

During the descending process of the mixture of steel shot and impurities, it is pushed by the horizontal airflow to the particles, thereby forming a skewed curved trajectory. Due to the difference in the specific gravity and particle size of the particles, the degree of deflection is not the same, so that the slag can be After separation, the dust is sucked into the dust collector for purification treatment, the broken pellets, sand, oxide skin, etc. enter the waste storage hopper, and the qualified shot blasting and some small pieces of debris are screened again and enter the storage hopper for recycling.

The better separation effect of the separator is achieved by adjusting the position of the weight on the gate, the position of the adjustment plate on the primary and secondary skimmer, and the butterfly valve on the pipeline. Reasonable adjustment can obtain a good separation effect and make the separation the efficiency can be as high as 99% or more.

The shaft of the cloth spiral is equipped with a pulse wheel, which can detect and follow up the working status of the cloth spiral. Once there is a failure such as blocking and not rotating, the signal will be immediately fed back to the PLC to start an emergency signal or stop gradually to ensure the safe operation of the equipment.

The choice of steel shot is directly related to the cleaning effect of the workpiece and the surface quality of the workpiece. The grain size and material of the steel shot are selected according to the difference of the cleaned workpiece.

working principle of the separator

3. The working principle of bucket elevator

The bucket elevator is composed of a cycloidal pinwheel reducer, upper and lower belt pulley, conveyor belt, hopper, closed covers, and tensioning devices.

The inlet of the bucket elevator is connected with the screw conveyor, and the outlet is connected with the separator.

The cover of the bucket elevator adopts bending forming welding structure. There is an inspection door on the elevator cover, which can repair and replace the bucket. Open the inspection door on the lower cover to repair the lower transmission and eliminate the blockage of the steel shots at the bottom. This machine uses a flat belt to rotate. When working, the hopper fixed on the conveyor belt scrapes up the abrasive at the bottom of the elevator, and then is driven by the elevator motor to send the abrasive to the top of the elevator, and then drop the abrasive by centrifugal gravity. Enter the steel shot and impurity separator.

In order to ensure that the conveyor belt does not slip during work, the roller is made into a squirrel cage type, which not only improves the friction between the lifting belt and the pulley, avoids the slipping phenomenon of the old-fashioned smooth pulley, but also reduces the pre-tightening force of the lifting belt. Extend the service life of the lifting tape. At the same time, the hoist is equipped with a set of tensioning devices. When the belt is slack, the belt can be tightened by adjusting the adjustment bolts on both sides of the upper part of the hoist.

4. The working principle of dust collector

When the dust-containing gas enters a large settling chamber because the cross-sectional area of the settling chamber is much larger than that of the dust suction pipe, the dust-containing gas flow rate of the shot blasting machine for sale is greatly reduced, and the flow rate can be reduced by 10-20 times. During the period of time when the dust-containing gas passes through the settling chamber, the larger dust particles have enough time to settle down under the action of gravity in the settling chamber, and the purified dust-containing gas is discharged from the other end of the settling chamber. Since the settling chamber is a dust collection device that uses gravity to make the dust settle naturally, it is also called a gravity settling chamber, or settling chamber for short.

The settling chamber of the dust collector of the shot blasting machine has the advantages of simple structure, low cost, low energy consumption, low-pressure loss, simple maintenance and management, and the ability to directly process high-concentration dust-containing gas. But its large size and low dust collection efficiency are its fatal shortcomings. In the past, the sedimentation chamber was mostly used in industry to collect dust particles >40um, or used as a pre-collection of the multi-stage dust collection system.

working principle of dust collector