Plunger Pump

Plunger Pump Points : Plunger Pump The plunger type pump lends itself radially to variable delivery, high pressure, and smooth flow and, alone or together with a constant- delivery unit, is an important factor in many hydraulic applications. In the under type of pump the piston, or plunger, which fits closely in its cylinder, draws in the oil as it moves outward and expels the oil as it is pushed back. These pumps have five or more radial cylinders, each of course, with its plunger.

Which is a sort of stud shaft with oil ports and passages, is fixed; that is, it does not revolve, nor is its position changed at any time. Second the cylinder barrel carries in its radial cylinder bores the plunger-pistons A, B, C, D, and E. It rotates on the spindle and therefore is not adjustable. Third, the plunger heads work against the reaction ring. which is carried by the rotor , and the ring and the rotor will therefore rotate with the cylinder barrel .Forth, the rotor and the ring are carried in the adjustable slide bock and therefore may be adjusted off center of rotation of the cylinder barrel by an amount equal to the distance X.. Fifth, since the plungers are kept always against the reaction ring, and the rotation of the cylinder barrel is out of center of the rotating reaction ring, the plungers will be given a reciprocating movement in their cylinders. Note plunger E pushed in, and plunger B pulling outward, in their respective cylinders. Sixth, the pintle has two lengthwise oil passages, one acting as in take or suction port, and the other as the outlet or pressure port. Seventh, the piston C, which has been pulled outward and has filled its cylinder with oil, has just started to push the oil from its cylinder into the outlet port and the piston A is well started in drawing the oil from the suction port. In action the pump shaft is driven clockwise at constant speed. This rotation is transmitted through a suitable coupling to the cylinder barrel mounted on the pintle . The plungers in the rotating barrel are confined in the rotor by the reaction ring while the rotor is carried on antifriction bearings in the adjustable: slide block. may be varied from zero to maximum. Also, by moving the slide block to bring the rotor to the other side of center, the flow of oil from the pump maybe reversed. The port then becomes the intake port.

The “creep” of the plunger heads on the ring, caused by the constantly .changing are distances between the plunger-heads is adjusted (compensated) by a slow movement of the convex plunger head on the surface of the ring, which gives a slight rolling of the plunger in the cylinder, in one direction during half its whirl around the pintle, and in the other direction during the other half.