SUCKER-ROD PUMP PLANT Russian patent published in 2014 - IPC F04B47/02 

FIELD: engines and pumps.

SUBSTANCE: proposed plant comprises flow strings. It includes cylinders with different-diameter steps arranged one above the other and hollow plungers, smaller diameter bottom plunger and larger diameter top plunger equipped with pressure valve and suction valve, respectively. Pressure valve is arranged in pressure valve box at smaller-diameter plunger end. Valve box diameter is larger than that of smaller-diameter plunger to allow increasing the pressure valve diameter which ups the efficiency of pump plant owing to easier access of thick has-fluid mix into said plunger. Maximum distance between pressure valve box top to the point of joint between cylinder steps is larger than plunger stroke. Larger diameter plunger cavity communicates with cylinder cavity via bores, with smaller diameter plunger cavity via pressure valve and with filter bed via suction valve which ensure normal serviceability of this pump plant. Cylinder top part is provided with toroidal weights to prevent its moving at upward string motion while bottom part is equipped with rubber rings to seal the cylinder seat equipped with scraper bush for cleaning the plant filter arranged in hollow part of filter bed.

EFFECT: higher efficiency of operation, longer life.

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