ENERGETICALLY-EFFICIENT HYDRAULIC UNIT FOR OIL PUMPING UNIT

摘要

The invention relates to a hydraulic unit which an oil pumping unit is equipped with, in order to actuate the hydraulic cylinder of the unit. The claimed unit comprises a framework (A) on which a tank (B) containing hydraulic fluid is fixed, a system (C) for heating or cooling the tank (B) being fixed to the framework (A), on a lid of the tank (B) there being a temperature sensor (1), a pilot circuit (2) with accumulators, a hydraulic block (3), a control apparatus (4) and pressure control apparatus (5), an electric motor (6) being mounted to the framework (A), a flange thereof having integrally mounted a flange (7), which is integral with some constant delivery and variable delivery and ratio adjustment pumps (8, 9), respectively, the constant delivery pump (9) being provided with a pilot circuit (10), the pumps (8, 9) being driven by a shaft of the electric motor (6) by means of an resilient coupling, using a common shaft, on the framework (A) there being an electric panel, a hydraulic block (11) being provided with an accumulator (12) for storing the recovered energy, having a control apparatus (13) and some valves (14 and 15) for actuating a hydraulic cylinder (16) of the pumping unit, a transducer (17) mounted on a pipe for collecting the pumped oil, the stroke-end sensors (a and b) and a displacement transducer (c), suitably mounted on the hydraulic cylinder (16) to permit the working beam pace to be regulated by means of a proportional pilot circuit (10), a cooling unit (18) and a filtering system (19) ensuring the hydraulic fluid normal parameters, a proportional throttle (20) permitting the regulation of the descending speed and braking speed, upon the control of the above-mentioned second stroke-end sensor (b).