Reciprocating vacuum pump

Reciprocating vacuum pump (abbreviated as reciprocating pump) also known as piston vacuum pump, belongs to one of the low vacuum acquisition equipment. Compared with the rotary vane vacuum pump, it can be made into a large pumping speed pump; compared with the water ring vacuum pump, the efficiency is slightly higher. The main disadvantages of such pumps are complex structure, large volume and large vibration during operation. It can be replaced by liquid ring vacuum pump on many occasions.

The structure and working principle of the reciprocating pump are shown in the figure. The main components are cylinder 1 and piston 2 in which reciprocating linear motion is performed. The driving of the piston is accomplished by crank connecting rod mechanism 3 (including cross head). In addition to the above main components, there are exhaust valve 4 and suction valve 5 and other important components, as well as the frame, crankcase, dynamic seal and static seal and other auxiliary components.Vacuum Pump


When running, driven by the motor, the piston in the cylinder can reciprocate through the action of the crank and connecting rod mechanism. When the piston moves from the left end to the right end of the cylinder, the density of the gas in the cylinder decreases with the increase of the volume of the left chamber of the cylinder, thus forming the pumping process. At this time, the gas in the pumped container enters the left chamber of the pump body through the suction valve 5. When the piston reaches the most right position, the left chamber of the cylinder is completely filled with gas. Then the piston moves from the right side to the left side, when the suction valve 5 is closed. The gas in the cylinder is gradually compressed as the piston moves from right to left. When the pressure in the cylinder reaches or slightly exceeds one atmospheric pressure, the exhaust valve 4 is opened and the gas is discharged into the atmosphere to complete a working cycle. When the piston moves left to right again, it repeats the previous cycle, so repeats, and eventually reaches a stable equilibrium pressure in the pumped vessel.

Application of vacuum pump in sugar industry