Orival OR-02-PE, Operation And Maintenance Manual, Page: 50 / 51

ORIVAL, INC. • 213 S. Van Brunt St. • Englewood, NJ 07631 • (201) 568-3311
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If the pin does not reach the end of its stroke in time, just increase the rinse time setting
in the controller.
If the pin reaches the end of its stroke too soon and the rinse time has been properly set
to the recommended interval, then this stroke must be slowed down. This can be
accomplished with the addition of a flow control needle valve in the piston’s hydraulic
tubing line. ORIVAL can supply this valve. The valve is a bi-directional check valve that
can have its flow adjusted in one direction. When used and properly adjusted, it will
slow the flow out of the piston to provide a gradual movement of the dirt collector to
allow a thorough cleaning of the screen.
The installation of this flow control needle valve is easy. See drawing on page 45.
1. Disconnect the piston’s hydraulic tubing line at the two-stage manifold.
2. Remove the vacated elbow fitting at the two-stage manifold.
3. Thread a short ¼’’ nipple in the open port.
4. Thread the flow control needle valve onto the nipple noting to use the low-
pressure port of the valve.
5. Thread the elbow fitting removed in step 2 into the valve’s other port.
6. Reconnect the piston’s tubing to the elbow fitting.
7. Perform several manual rinse cycles while observing the piston’s pin and making
adjustments to the flow control needle valve. The ideal adjustment is reached
when the pin reaches the end of its stroke just as the rinse solenoid is de-
energized. This allows a brief period before the rinse valves close while the dirt
collector is at the end of its stroke.
It is also important to remember that the efficiency of the cleaning and rinsing is
dependent on the dirt collector nozzles’ ability to always remove the particles. Having
the proper pressures and a slow, deliberate dirt collector travel provides the best
conditions for the nozzles to do an efficient cleaning job. However, filter and nozzle
maintenance must also be performed. The PVC nozzles wear with time as particle are
sucked across its tips and into the openings. With wear, the tips get shorted and the
distance to the dirt increases. This reduces the suction effect. Inspection of nozzle tips
for wear should be part of routine filter preventive maintenance.
Also, the dirt collector is suspended on the center axis of the screen. With time, the dirt
collector shaft and upper bearing may wear and cause a dirt collector mis-alignment.
And a similar mis-alignment can occur at the dirt collector’s rear support of the lower
bearing and piston bushing assembly. These low cost parts should be inspected and
replaced if any signs of wear are observed or when filter performance has decreased.