MULTI-SCREW AND MULTI-STAGE PUMP AND METHOD OF MANUFACTURING SAME Russian patent published in 1997 - IPC

FIELD: pump engineering. SUBSTANCE: race consists of several parts the number of which is equal to the number of pressure stages. Each of the parts extends along one pressure stage and is enclosed by individual counter-pressure chamber. The method of manufacturing the race comprises machining the parts of the race providing a necessary configuration of bores for screws, facing the parts, making ring grooves, drilling through openings for counter-pressure chambers, and preliminary machining to the outer diameter. The parts of the race are then assembled to provide a stack. The stack is finished to the outer diameter and openings are drilled for pins used for locking mutual angular position of the parts of the race. EFFECT: improved design of the pump and simplified method of its manufacturing. 2 cl, 1 dwg