Pneumatic diaphragm pump inspection 1. Ensure that the air supply pressure is at least 0.35bar(5psig) above the pressure head and that the pressure difference (the difference between the air supply pressure and the liquid discharge pressure) is not less than 0.7bar(10psig). 2. Check whether the filter membrane at the air inlet is blocked by foreign bodies (see recommended installation). 3. Check the air leakage (leakage), which will show whether there is bad seal or small hole on the air valve, guide shaft and main shaft. 4. Disassemble the pneumatic diaphragm pump and check whether there are obstacles in the gas path or whether there are objects that hinder the operation of the internal parts. 5. Check whether the check valve is adhered. If the pumped liquid is not compatible with the elastomer of the pump and will expand, replace the check valve and the ball seat with the appropriate elastomer. In addition, the ball will become smaller due to wear, which may cause the ball to get stuck in the seat, in which case the ball and seat should be replaced. 6. Check whether the inner pressure plate is damaged, which will prevent the movement of the valve shaft. 7. Remove the plug from the exhaust end of the guide shaft to check whether the exhaust end of the guide shaft is blocked. Pneumatic diaphragm pump maintenance pump action, but the flow is small or no liquid outflow: 1, check the hole phenomenon of pneumatic diaphragm pump, reduce the pump speed to make thick liquid into the liquid cavity. 2. The height of liquid lifting under vacuum required by verification is not greater than the vapor pressure of liquid being pumped (hole phenomenon). 3. Check whether the check valve is glued. If the pumped liquid is not compatible with the elastomer of the pump and will expand, replace the check valve and the ball seat with the appropriate elastomer. In addition, the ball will become smaller due to wear, which may cause the ball to get stuck in the seat, in which case the ball and seat should be replaced. Pneumatic diaphragm pump valve icing: check whether the compressed gas is too wet, can be installed by the dryer or hot air generator for compressed gas treatment. Alternatively, in some cases a condensate filter may be installed to remove moisture from the compressed gas. Air bubbles at the outlet of pneumatic diaphragm pump: 1. Check whether the diaphragm is broken. 2, check the tightness of the external pressure plate. 3, check bolt torque and O-ring and seat integrity, especially suction pipe. 4. Ensure that the pipe connection is sealed. Product outflow from gas outlet: 1. Check whether the diaphragm is broken. 2, check the sealing of the external pressure plate and shaft.
