Sealless Pressure Regulating Valves

Assuming your pump system is properly sized, pressure regulating valves enable your high pressure coolant pump system to maintain a constant pressure no matter which tool or the number of tools requiring coolant.

Although it is possible to control the volume of coolant by controlling the pump/motor shaft speed using a programmable pump controller and customized PLC, most high pressure coolant systems simply let the pump system operate at full flow when high pressure coolant is required and letting the pressure regulating valve  "send" the correct amount to the machine tool, bypassing the "extra" flow back to the coolant sump.

The pressure regulating valve supplied with our high pressure coolant pump systems are sealless, which means that there have no sliding or rotating components exposed to the reclaimed machine tool coolant.  This is important because conventional designs have o-rings seals which wear and leak due to the fines within the recycled coolant.

 

How A Pressure Regulating Valve Works

Fluid enters one side and exits the other.  In the center of the valve is a valve seat which has a hole in it, enabling fluid to exit through the bottom of the valve.  The valve seat is normally plugged shut with a spring loaded plunger.  The valve chamber is machined such that the differential pressure is negligible.

The user can adjust the force causing the plunger to seat onto the valve by compressing a spring.  Fluid only bypasses the system and discharges through the bottom of the valve when the system pressure exceeds the pressure of the spring keeping the plunger in-place.

Therefore, as long as you have sized your pump based upon the largest capacity tool used, the maximum pressure remains constant regardless of your tool size because the "excess" flow that isn't required for the smaller tools simply bypasses back to the sump.