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HYDRAcone
1. Fill the pump with the appropriate oil.
2. Set stroke length adjustment to maximum stroke setting.
3. Turn on the pump motor.
4. Loosen the pressure relief valve located at the top of the hydraulic system to atmosphere
and any air present will vent back into the gearbox oil reservoir as the automatic makeup
valve fills the piston/diaphragm chamber. Air bubbles will be evident at the vent hole, top
center of pump head behind return spring.
5. When last traces of air have been expelled retighten pressure relief valve.
6. Reconnect pump to process and adjust pressure relief valve to desired setting using
pressure gauge in the process line. Approximately a ½ turn more after process pressure
setting has been reached will seat valve. The valve can be set higher if desired but do
not exceed Maximum Operating Pressure indicated on the pump nameplate.
7. After the pump has run for several hours, again check for any last traces of air at the
pressure relief valve.
Double Diaphragm Flat Leak Detection
Please refer to Appendix I for detailed information for priming of the Leak Detection Diaphragm.
8.6 Check Valves
Description of Check Valves
Most fluid metering problems are related to check valves. Problems usually stem from solids
accumulation between the valve and seat, corrosion of seating surfaces, erosion, or physical
damage due to wear or the presence of foreign objects.
The check valve incorporates a ball or disc, guide, and seat. Flow in the unchecked direction lifts
the ball or disc off the seat, allowing liquid to pass through the guide. Reverse flow forces the ball
or disc down, sealing it against the sharp edge of the seat. The guide permits the ball to rotate
but restricts vertical and lateral movement to minimize “slip” or reverse flow. Ball rotation prolongs
life by disturbing wear over the entire surface of the ball.
Since check return is by gravity, the valve must be in the vertical position to function properly.
The guide and seat are sealed by O-rings.
Figure 35
