Continuous working sandblasting machines are liked by some industries because of their high work efficiency. However, continuous working sandblasting machines are not as good as other sandblasting equipment due to frequent operations. Improve continuous working sandblasting machines The processing quality has become a concern of everyone. Belden Machinery, as the largest sandblasting machine production base in Asia, once made an improvement plan for a shipyard to improve the processing quality of continuous working sandblasting machines. Let’s share:

 

Sandblasting machine

The continuous work sandblasting machine is currently the most widely used in the shipyard's segmented coating workshop, and its traditional control process is shown in Figure 3. During sand blasting operation, the lower silo maintains pressure and the upper silo adds sand. When the upper material level detector sends out a full silo signal, the sanding stops. When the lower material level detector sends an empty silo signal, the upper silo blocking valve rises to maintain pressure. The blocking valve of the lower silo automatically falls, and the abrasives in the upper silo automatically fall into the lower silo. This process is controlled by a timer. When the time is up, the upper silo will exhaust and release the pressure, and add sand again. Before the improvement, the capacity of the upper bin of the sandblasting machine is required to be less than that of the lower bin, so that after the abrasive in the upper bin falls to the lower bin, its material level is lower than the lower end surface of the blocking valve, ensuring that there is no abrasive during the ascending process of the blocking valve. To protect the blocking valve and sealing ring. Due to the small capacity of the upper bin and frequent sand additions, the wear of the sandblasting machine is increased. Every time when the machine is turned on, the lower chamber sealing valve is not tightly sealed and air leakage occurs. This is because there are abrasives in the upper and lower chambers when the machine is turned off last time, and the lower chamber sealing valve falls after the pressure is relieved. , The upper silo abrasives will follow the fall, the lower silo sealing valve is submerged in the abrasives, and the abrasives are trapped between the sealing valve and the sealing ring, which causes the eccentricity of the sealing valve to rise, causing air leakage and making the sandblasting machine unable to work normally. , It also increases the wear of the plugging valve and the sealing ring. During the operation, the time for adding sand from the upper silo to the lower silo is controlled by a timer. The length of the timing should be appropriate. It is necessary to ensure that the abrasives in the upper silo completely fall into the lower silo, and to ensure that the abrasive is within a cycle period. The supply is continuous, so the timing should be accurately determined.

 

Principle 1 before improvement of sandblasting machine

 

Figure 4 shows the control flow of the improved continuous work sandblasting machine. First turn on the air source of the sand blasting machine, inflate the lower bin, raise the block valve of the lower bin, then turn on the power of the sand blasting machine, open the sand filling valve, and add sand to the upper bin, when the upper bin level indicator sends out a full bin signal After that, stop adding sand and inflate the upper bin. The upper bin sealing valve is raised, the upper bin keeps the pressure, and when the pressure in the upper and lower bins reaches equilibrium, the lower bin plugging valve's own weight drops, and the abrasive in the upper bin enters the lower bin. Two warehouses are combined into one. As the sandblasting operation progresses, the material level of the lower bin drops. When the lower bin material level detector sends out an empty bin signal, the upper bin stops air intake, and at the same time exhausts and releases pressure, the lower bin block valve rises, and the lower bin can maintain pressure. Continue to work. After the upper bin is relieved of pressure, the blocking valve drops, the sanding valve opens, and the upper bin enters the feeding state. When the upper bin material level detector sends out the full bin signal, the sanding is stopped, and the work is repeated continuously.

 

The improved sandblasting machine increases the capacity of the upper silo, reduces the number of sand additions to 4000, and reduces the wear of the blocking valve. After the upper silo is filled with sand, the upper silo maintains the pressure, the lower silo sealing valve drops, and when the lower silo sealing valve rises again, the lower silo is empty, so as to ensure that the sealing valve has no abrasives during the ascending process. The air leakage caused by the eccentricity of the plugging valve ascends, which also reduces the wear of the plugging valve and the sealing ring. When the upper bin is filled with sand, the upper and lower bins are combined into one, no timer control is required, and the action is simpler.

 

Principle 2 before improvement of sandblasting machine

 

The structure and control process of the sandblasting machine have been improved. At the same time, it is very important to improve the control program. Engineering and technical personnel must pay attention to the following issues when writing the program.

 

(1) The collected material level detector signal must be filtered. When the material level detector sends a signal and keeps it for 2s, it will be regarded as a valid signal to avoid misoperation.

(2) It is advisable to set the exhaust time of the upper warehouse to 30s, which can be adjusted according to the capacity of the upper warehouse.

(3) After the sanding valve is closed, delay about 10s before flushing the upper chamber to ensure that all abrasives have fallen to the upper chamber when the blocking valve is raised In the warehouse. In addition, some auxiliary functions have been added to the operation, such as each sandblasting machine can be initialized separately, and each sandblasting machine can be interrupted to add sand, which is convenient for operation and maintenance. If the processing accuracy and assembly accuracy of the sandblasting machine parts are not up to the requirements, the sandblasting machine will not work normally, which should be paid attention to.