LUFKIN RHA API Pump

Don-Nan RHA API insert pumps are heavy-walled, stationary barrel, top anchor pumps recognized by API as a standard design — built for wells where sand fallback on shutdown is a recurring problem.

These pumps are suited to moderate-depth wells with high sand fallback on well shutdown. Fluid dispersion directly above the seat nipple prevents the pump from sticking when sand settles back around it after the well is shut in — a common failure point for standard insert pumps in sandy formations.

The RHA's heavy-walled barrel is less pressure-sensitive than the similar Don-Nan RWA pump, which means it can typically be run slightly deeper than the thin-walled RWA insert pump. If your well doesn't have significant sand fallback, the RWA is usually the more cost-effective choice; the RHA earns its heavier barrel specifically in high-sand-fallback conditions.

RHA pumps are available with mechanical or cup-type seating. A mechanical hold-down doesn't need repair unless it sustains major damage, while cup hold-downs should be replaced every time the pump is unset. Both types follow the same set/unset procedure: setting is done by lowering the sucker rod weight onto the pump, unsetting by lifting it back up.