China Pumping Solutions Leader
Pneumatic diaphragm pump is a positive displacement reciprocating pump driven by compressed gas. The aodd pump is composed of two parts of the air flow structure and the liquid flow structure, and is completely isolated by the diaphragm on both sides. The air source pressure needs to be greater than two kilograms per square centimeter to work. Under the working pressure of 5 to 8 kg, the high pressure gas in the air valve chamber drives the connecting rod shaft to do left and right reciprocating movement through the air flow channeling system, and the low pressure gas after consumption is quickly discharged through the exhaust port. Under the alternating action of high and low pressure gas on both sides, the connecting rod shaft drives the diaphragm on both sides to move left and right, so that the air pressure in the volume chamber on both sides changes alternately, so as to achieve continuous suction and discharge of liquid.
Pump does not run or runs slowly.
Ensure that the intake pressure is at least 0.4 bar(5 psig) higher than the starting pressure, and the pressure difference (the difference between the intake pressure and the discharge pressure) should not be less than 0.7 bar(10 psig).
Check the air intake filter for debris.
Check for serious gas leaks (air leaks), which indicate worn seals/bores on the air valve, pilot spool, and spindle.
Remove the pump and check for obstacles or objects in the air passage that would impede the movement of the internal parts.
Check whether the ball check valve is stuck. If the material to be pumped is not compatible with the elastomer of the pump, swelling may occur. Replace ball check valves and seals with appropriate elastomers. Also, as check valve balls wear out, they get smaller and can get stuck in the seat. In this case, replace the ball and seat.
Check the inner piston for damage, which will cause the air valve spool to be unable to move.
Remove plug on pilot spool exhaust port.
Connect the test light to the two leads leading to the pump and make sure the light cycles on and off. Ensure lamp voltage and current requirements with Accu-Flo? Coil voltage and current requirements are the same.
Make sure to switch the air valve manual override control (small red knob on the front of the valve) to the “0” position.
Check the pilot pressure vent at the top of the operator/coil assembly to ensure that it is not blocked.
Check the valve for wear. If the air continuously sweeps away a large amount of exhaust gas, the valve seal may wear and fail to work properly. In this case, the valve must be replaced.
Note: Cost savings can be achieved by completely disassembling the valve, cleaning all components, and re-lubricating the valve before scrapping it.
Check the intake filter and air filter for debris.
Check if the valve is stuck and flush the valve with solvent.
Check the valve for wear. If the piston face of the air valve becomes bright instead of dull, the air valve may be worn out, out of working tolerance, and must be replaced.
Check the central body ring. If they wear too much, they will not seal and the air will simply flow through the pump and out of the exhaust port. Because of their special structure, use only rings.
Check that the piston in the valve is rotating. This indicates that the guide pin has failed.
Check the type of lubricant to be used. Oil with a higher viscosity than recommended may cause the piston to stick or run abnormally. An oil with anti-freeze characteristics (ISO 15-5 weight) is recommended.
Second, the pump runs, but there is little or no product flow.
Check the pump for cavitation. Slowly reduce the pump speed to allow the thick material to flow into the liquid chamber.
Verify that the vacuum required for the fluid suction height is not greater than the vapor pressure (cavitation) of the material to be pumped.
Check whether the ball check valve is stuck. If the material to be pumped is not compatible with the elastomer of the pump, swelling may occur. Replace the ball check valve and seat with an appropriate elastomer. Also, as check valve balls wear out, they get smaller and can get stuck in the seat. In this case, replace the ball and seat.
Check that the discharge isolation valve is closed.
Check if the speed of the electrical signal is so slow that the physical stroke cannot be completed before the signal to change direction is sent. The time required to complete the stroke is determined by a number of factors, including fluid viscosity and indenter pressure. If the muffler is removed, the shaft can be seen (not available on all models).
Ensure that the supply pressure is high enough to meet the application head pressure requirements.
Check the cavitation of the pump; Reduce the pump speed to match the thickness of the material to be pumped
Check whether the ball check valve is stuck. If the material to be pumped is incompatible with the pump elastomer, swelling may occur. Replace the ball check valve and O-ring with an appropriate elastomer.
Check and ensure that all suction connections are airtight and that the clamp rings are properly tightened.
Check the cavitation of the pump; Reduce pump speed to match thickness of material to be pumped.
Check whether the ball check valve is stuck. If the material to be pumped is not compatible with the elastomer of the pump, swelling may occur. Replace the ball check valve and O-ring with an appropriate elastomer.
Check and ensure that all suction connections are airtight, especially the clamp rings around the air intake.
Three, the pump valve freeze.
Check if there is too much moisture in the compressed air. Install a dryer or hot air generator to produce compressed air. Alternatively, in some applications, a coalescence filter may be used to remove moisture from compressed air.
There are bubbles in the pump outlet.
Check the diaphragm for rupture.
Check the tightness of the outer piston.
Check the tightness of fasteners and the integrity of O-rings and seals, especially at the intake manifold.
Make sure pipe connections are airtight.
Fourth, the product is discharged from the exhaust port.
Check the diaphragm for rupture.
Check the sealing of external piston and shaft.
Five, the pump appears crunch.
Forming the wrong discharge head or suction height
Six, the solenoid valve appears buzzing or the solenoid valve is burned out.
The voltage is incorrect, the solenoid valve is faulty or dirty.
Seven, the solenoid valve can not be electrically shifted, but it can be manually controlled.
Incorrect voltage, poor coil or wiring.
Eight, the solenoid valve can not be electric or manual beyond control shift.
Insufficient air supply, contamination, inadequate or improper lubrication, and valve bonding.
- The valve is displaced but cannot be returned.
Spring break, mechanical bond.
- Excessive leakage of air valve exhaust port.
The seal in the air valve is worn.
The air passage of the pump is blocked by ice.
Check whether there is too much water in the compressed air line. As air is discharged from the exhaust port during the operation of the pump, water vapor trapped in the compressed air can freeze and block the air passage in the pump. If this happens, you may need to install a coalescence filter, an air dryer, or a hot air generator for compressed air.
