This assembly is adapted to use air-controlled sand control valves.If a manual sand control valve is used, the pressure in the sand cylinder will continue to press sand into the sand blasting pipe after the air source is turned off, causing sand blockage.
Two) Pressure-relieving pressure mobile sand blasting machine: automatic exhaust air cut-off valve directly controls the main air source switch, and at the same time switches the sand cylinder and the side main air pipe to operate.
Features: The sand blasting machine operates automatically for each operation, and is operated by one person, which is simple and convenient. When each operation is completed, the air control switch is released, and the sand cylinder is automatically vented, which is safe and reliable. At the same time, the pressure relief can reduce sand blocking.
Pressure mobile sand blasting machine is a kind of thermal spraying pre-processing machine. It uses compressed air as the power to spray clean and dry abrasive at high speed to the surface of the workpiece to be sprayed to meet the requirements of surface cleaning and hairening. It can also remove paint, The effect of removing rust on welds, and blasting for preparing frosted glass and other workpieces is very significant. The cleaning level reaches SA2.5-3.0, and its roughness meets process requirements. The product has a wide range of uses, compact structure, simple maintenance, easy to use, etc. It is a necessary machine for thermal spraying (welding) various anticorrosive layers.
The pneumatic remote control system of the pressure-relieving pressure mobile sand blasting machine is composed of an intake valve, an automatic exhaust valve, a control air pipe, a manual control switch and an air-controlled sand control valve assembly.
When working, the handle is depressed, and the air flow is controlled to reach the manual control switch through one air pipe (the A port on the shut-off valve), and is discharged to the air inlet (port B) on the stop valve through the other air pipe, so that the main The air inlet valve of the pipeline is opened, and the air source entering the sand cylinder and the cylinder side air supply pipe is operated. At the same time, the air source coming in from port B is flushed out to the exhaust valve and the sand regulating valve through the exhaust port (c port) on the stop valve. The sand control valve opens and the exhaust valve closes. At this time, the pressure in the sand cylinder rises, and the blasting operation starts.
The characteristics of this model are that each time the three valves, air shut-off valve (intake valve), automatic exhaust valve, air-controlled sand control valve, must be activated, the gas of the blasting cylinder will increase and discharge, and every time All the switches have a certain time, because all the gas from the blasting cylinder is exhausted, and the operator can lower the nozzle.
(Due to the use of pneumatic remote control abrasive valve, when shutting down, the sand regulating valve is normally closed. When starting up, the air pressure impacts the rubber lining in the sand valve, and the impact pin against the rubber core in the I-shaped seat will loosen. The valve is open. Therefore, every time the switch is opened, there will be a certain amount of storage in the sand tube, and there will be an instant pulse when the gun is fired.)
This system is not suitable for sandblasting operations longer than 20m, because the pneumatic remote control reaction has a lag time. For sandblasting operations longer than 20m, it is recommended to add a power distribution control system to greatly reduce the reaction time. If it is necessary to use pneumatic control, it is better to use a manual butterfly sand adjustment valve with 45 degrees of sand output, and also have to endure a delay of 3-5 seconds, or use our new air shutoff valve (the latest design, Add a control port for the instant exhaust hole D port), which can exhaust instantly, reduce the delay, and produce a control response in 1 second.
I. System parameters of this model:
1. Main technical parameters and structure of equipment
1) Main technical parameters
Cylinder block diameter: 600mm Sand blasting efficiency: 15-35 square / H
Cylinder height: 1300mm Blasting grade: SA2.5-3.0
Volume: 0.3-0.6 cubic metersAir consumption: ≥3 cubic meters / min
Air supply pressure: 0.6-0.7Mpa
Features: pneumatic control, low failure rate, less wearing parts, less investment, high efficiency, wheeled structure, fixed-point and mobile sandblasting, easy to move.
Connect all connections and circuits and all pipelines as shown in the figure, and check whether they are firm and sealed.
Check whether the pneumatic control system is normal and whether the manual control switch is normal.
Check that the exhaust valve is closed.
Wear a protective mask for sandblasting.
1) Connect the sand blasting machine to the air source with an air hose and tighten it correctly.
2) Connect the blast tube to the quick connector of the abrasive valve outlet and lock it.
3) Start the air compressor so that the indicated pressure reaches the required working pressure. The air compressor is placed on the air outlet of the sand blasting machine to prevent dust caused by sand blasting from being sucked into the air compressor.
4) Put the clean and dry abrasive into the barrel of the sand blasting machine.
5) Wear protective equipment for sandblasting.
1) The sand blaster holds the sand blasting gun to prepare for work and closes the manual sand control valve;
2) Press the manual control switch, the intake valve delays for a few seconds, and the air source is turned on.
3) After venting, the high-pressure air automatically opens the air inlet valve (air shutoff valve), closes the air release valve, the air enters the sand cylinder, and the cylinder is pressurized. The umbrella-shaped seal valve automatically lifts up to seal the inlet and the pressure in the sand blasting machine. Continue to raise, the blast gun can automatically enter the blasting state. At this time, only air flows out of the nozzle.
2) During the blasting operation, according to the blasting state, adjust the handle on the hand-controlled abrasive valve to adjust the abrasive outlet flow. The abrasive flow should not be too large. Observe under the sun or other bright light sources. There is not much difference between air flow and pure air flow.
Because the machine uses a pneumatically controlled sand control valve, the valve core in the I-shaped seat is closed during normal shutdown, that is, the left screw is adjusted to the middle part of the sand valve rubber core, and the nut under the right hand of the sand control valve is adjusted. Squeeze the right cross beam in the I-shaped seat, so that the cross beam squeezes the rubber core to the left to the middle, and closes with the rubber core top of the left screw to form a close, that is, the left screw and the right nut are tightened to the valve core When the manual control switch is pressed, after the compressed air enters the sand control valve, the rubber pad inside the sand control valve will be squeezed, which will cause the spring to contract and the right beam in the I-shaped seat to return, thereby opening the inner channel of the rubber core and the abrasive passing Sand valve, forming sand blasting work. (Manual valve does not need to look at this part, just manually adjust the sand amount to a suitable position.)
3) At the end of the operation, release the manual control switch. Within a few seconds after losing the control signal, the machine automatically closes the air intake valve, opens the air relief valve, exhausts in the cylinder, and the blasting gun automatically stops the blasting operation slowly.
After the sand blasting operation is completed, the power supply and intake valve must be turned off, the air compressor must be turned off, and the remaining abrasive in the cylinder must be cleaned to prevent wet agglomeration or block sand.
When the blasting machine takes a long time to shut down, the abrasive in the barrel should be cleaned to prevent failure due to the damp of the abrasive when it is reused. The steps to clean the abrasive are:
1. Remove the nozzle.
2. Place the sandblasting hose in a container.
3. Close the main air valve and exhaust valve and the abrasive valve is opened to the maximum.
4. Open the intake valve. Let the sandblaster work until you drain more than the abrasive in the cylinder.
The sand blasting machine should be covered when it is placed outdoors at night to prevent water from entering the bucket.
1.Replace closed valve (umbrella bucket)
Open the service port valve, and use a small pipe wrench to unscrew the connection (conduit) under the conical closed valve (umbrella bucket) and remove them from the barrel. Replace it with a new shut-off valve. Install the inspection hole cover and tighten all the screws.
2.Replace the inlet seal
Use your nails or a screwdriver to gently remove the old seal and press the new seal into the seal seat.
3. Regularly check the lubrication and wear of the O-rings, pistons, springs, gaskets and other parts in the intake and exhaust valves.
4. Clean the filter element in the filter twice a day to ensure the normal operation of the system. The filter element should be replaced in time if it is damaged or blocked.
1) No abrasive or air at the nozzle exit
Close the inlet valve and open the exhaust valve. After the pressure of the blasting machine is released, check whether the nozzle is blocked.
2) Abrasive with air
Open the abrasive valve to the maximum limit, quickly open it and then immediately close the main air valve (ball valve switch at the air inlet). If this method does not work, you need to open the inspection hole to clear the debris in the bucket or open the abrasive valve to clear the abrasive valve Internal blockage.
2. It is normal that the abrasive flow is slightly unstable. If the abrasive flow continues to be unstable, quickly open it and then immediately close the main air valve to eliminate this fault.
3.Remove dampened abrasive
Remove the blasting hose and the corresponding gasket, open the abrasive valve and the inlet valve, and the damp abrasive can be removed (note: the inlet speed of the abrasive is very high, and unrelated personnel must stay away from the inlet of the abrasive valve). Then close the intake valve, open the exhaust valve, and then connect the blasting hose after removing the nozzle to the blasting machine. Open the intake valve and the main air valve, and the wet abrasive in the blasting hose is also removed. Close the exhaust valve, and then connect the nozzle to the blasting hose. The blasting operation can be resumed in normal steps.
4, the exhaust valve does not exhaust or exhaust slowly
1) Clean or replace the filter element in the filter
2) Clean or replace the muffler
3) Replace the spring or film in the exhaust valve.
Effective pressure (MPa)
Cleaning efficiency m2 / h (Sa2.5—Sa3.0)
Air consumption (m3 / min)
Abrasive consumption (Kg / h)
Air consumption (m3 / min)
Abrasive consumption (Kg / h)
Air consumption (m3 / min)
Abrasive consumption (Kg / h)