One of the most prominent features of any SANDPIPER pump is the exclusive ESADS+Plus Air Distribution System that allows for quick remote site serviceability. Independent of the pilot valve position, the cross-drilled pressure ports in the main directional air valve spool provide a pneumatic bias of the spool at either end of travel. This is accomplished by directing (inner) chamber pressure to the end of the spool, boosting and sustaining pilot pressure until point-of-shift of the pilot valve.  The benefit of this is that it eliminates spool from drifting due to vibration and/or unbalanced pressure or system conditions.

Primary system components = main directional air valve (with PATENTED cross-drilled pressure ports) & pilot valve
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