LOCK SUPPORT OF INSERT OIL-WELL PUMP Russian patent published in 1996 - IPC

FIELD: oil industry. SUBSTANCE: support has mounting nipple and two-stage attachment housing. Mounting nipple is provided with flexible single-acting collar mounted in its upper portion and taking up the pressure differential directed upward. Diameter of lower portion of double-stage attachment housing exceeds that of upper portion. Mounting nipple, flexible collar and attachment housing form hermetic chamber filled with liquid. In starting the pump, attachment housing moves upward, thus decreasing the volume of chamber and increasing the pressure of liquid contained in it. Excessive pressure in chamber acts on circular area between stages, thus creating holding force. When it is necessary to lift, lock support opens in course of withdrawing the pump by rods within definite period of time due to leakage of liquid from chamber through clearances. EFFECT: enhanced reliability. 1 dwg