The sandblasting machine is a device for gas-powered transmission of sand to do work, and it has a very important application in oral dentistry. After intraoral medical staff perform ultrasonic cleaning on patients, they often use sandblasting to polish the surface of the teeth to consolidate the effect of dental treatment.
In dental restoration, sandblasting and polishing is one of the indispensable procedures when dental technicians are casting porcelain teeth.
1. Structure principle of sandblasting machine
The compressed air is used to transport sand powder particles from the sand storage tank to the surface of the object to be polished. This process is called sand blasting, and its function is to improve the roughness of the surface of the object. To make this process effective, the sand particles should be in a suspended and pulsating state. The most ideal working condition is to make the sand particles appear in a uniform suspended flow state in the pipeline. The proper sand flow rate and the proper compressed air flow rate are the key factors that determine the effect of sandblasting. The size of the compressed air should be such that the flow velocity of the air in the pipe is at least greater than the sedimentation velocity of the largest sand particle in the flow process. The aerodynamic force is sufficient to overcome the friction loss and resistance of the sand particles blown in the pipeline, so as to ensure the smooth flow of the sand particles in the pipeline.
Due to the influence of the length of the pipeline, the pressure of the compressed air will also drop to slow down the airflow speed. At this time, the sand particles will appear unevenly suspended. When the airflow is small to a certain extent, the flow of sand grains presents a pulsating state, and even some sand grains will be deposited at the bottom of the pipeline, and the other part will show a sliding forward motion. Finally, the sand grains block the pipeline and the sandblasting work cannot be carried out.
2. Failure phenomenon of sandblasting machine
In the process of sandblasting and cleaning in the oral cavity, since the sand particles are water-soluble salts, the sand powder will become moist and agglomerate when exposed to the air for a long time, which increases the friction between the sand particles. The moisture (moisture) in the pipeline adsorbs some sand particles, causing the sand particles to block the pipeline, causing the sandblasting machine to fail to work.
3. Troubleshooting of sandblasting machine
Once this happens, you can use the following methods to exclude:
(1) After removing the connecting member of the compressed air end of the pipeline, add compressed air in the reverse direction from the use end. When the blockage in the pipeline is not serious, this method can be used to break open the blockage and make the blocked pipeline unblocked.
(2) While adding compressed air in the reverse direction, tap the pipe with a stick to activate the glued sand particles and make them flow out of the pipe.
(3) If the above method still does not work, for the sandblasting machine that blasts the teeth in the oral cavity, you can consider soaking the pipeline with warm water, because the sand component of this kind of sandblasting machine is soluble salt. For the artisan sandblasting machine, the blocked part should be removed, the steel wire should be used for mechanical dredging operation, and then the sand particles on the pipe wall should be blown with air, reinstalled, and the pipeline should be blown dry with compressed air before being put into use.
If there is a control valve (such as an electric porcelain valve) in the sand road and the valve body part is blocked, the valve body must be disassembled, cleaned and reinstalled before use. Considering that the power supply failure of the control valve body causes the sand road to be blocked, then the control circuit is repaired and the fault is eliminated.
In the artisan sandblasting machine, in order to avoid sand and dust from polluting the working environment, a dust collector is equipped. Due to long-term use, the dust collector motor will be damaged.
Due to limited conditions, replacement of the original specification motor is expensive or difficult to buy, so it can be replaced by a household dust collector. By using the above-mentioned method to repair the sandblasting machine of this unit, the effect is very good.