Pump Isolation Valve - Nordson ProBlue P4 Customer Product Manual

D-2
SP Pump Diagnostics and Repair
Pump Function
Part 1024496_06
(contd)
When the air valve directs the stroke of the piston upwards, the piston
creates suction within the pump body, which opens the siphon ball valve and
closes the pressure ball valve. As the piston moves upwards, material is
simultaneously drawn into the pump below the pressure ball valve and forced
out of the pump chamber above the pressure ball valve. Material leaving the
pump chamber passes through a filter and then into a manifold, where it is
distributed to the hoses/guns.
Attached to the piston assembly is a shifter fork. The fork travels along the
shaft of the actuator assembly that has a magnet at both ends. When the
stroke of the piston carries the shifter fork upwards, a magnet in the shifter
fork attracts the magnet at the end of the actuator, which shifts the position of
the air valve. When the valve shifts, air is redirected to the opposite side of
the air cylinder, which forces the piston downwards.
On the piston downward stroke, material pressure below the piston closes
the siphon ball valve and opens the pressure ball valve. As the piston moves
downwards, material below the pressure ball valve is displaced, and forced
through the pressure ball valve and out of the pump chamber, where again, it
passes through the filter and into the manifold.

Pump Isolation Valve

To prevent siphoning of the tank when the pump is removed from the
manifold, the manifold is equipped with an isolation valve.
Pressure Discharge Valve
The manifold is equipped with a pressure discharge valve. When the pump is
switched off at the control panel, air is removed from the top of the valve
causing it to open. When the valve opens, pressurized material within the
pump and manifold is bypassed through the pressure discharge valve back
to the tank.
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