WLW series vertical oil-free reciprocating vacuum pumps
Instruction of the principle of reciprocating vacuum pumps
Reciprocating vacuum pump (also called piston vacuum pump) is one of the low-vacuum obtaining equipment. Its ultimate pressure is usually within 1330~2660Pa, and the pumping rate range is wider that is from 50L/S to 600L/S. Reciprocating vacuum pump is applicable to the vacuum impregnation, vacuum treatment of molten steel, vacuum distillation, vacuum evaporation, vacuum concentration, vacuum crystallization, vacuum drying, vacuum filtration in petroleum, chemical industry, medicine, food, light industry, metallurgy, electric and other industries, as well as pumping gases for the vacuum treatment of concrete and other areas, but either not applicable pump the gases which have excessive oxygen content, poisonous and explosive feature, corrosive effects to metals, and dust particles, nor act as a transfer pump to transfer gas form one container to another.
The functional diagram of reciprocating vacuum pumps is shown in the figure. The major components of a reciprocating pump include cylinder 1 and piston 2 which makes a straight reciprocating movement in the cylinder. The piston is driven by crank-link mechanism 3 (including the crosshead). In addition to the above components, there are exhaust valve 4, suction valve 5 and other important components, as well as the frame, crankcase, dynamic and static sealing, and other accessories. During the operation, driven by the motor, the piston in the cylinder makes a straight reciprocating movement thought the crank-link mechanism (rotary motion is turned to a rectilinear motion). When the piston traveling from left to right in the cylinder, as the volume of the left chamber of the cylinder increases, the pressure in the left chamber space continuously gets down, and when the pressure in the left chamber is lower than the that in the container in which the gas is pumped, according to the principle of gas pressure balance, the gas in the container is drawn into the left chamber through suction valve 5, that is, the pump is in the process of suction. When the piston reaches the right most position, the left chamber of the cylinder is full of gas. Then, the piston moves from right to left, and at this time, the suction valve 5 automatically closes. The gas is gradually compressed with the piston movement from right to left. When the gas pressure in cylinder reaches exhaust pressure, exhaust valve 4 is open, and the gas is exhausted to complete one working cycle. When the piston moves from the left to right, repeat the cycle until the pressure in the pumped container reaches a certain balance. In the reciprocating pump, suction valve and exhaust valve are very important components, and they wearing parts. Their working directly impact on the ultimate pressure, pumping rate, power consumption and reliability of running of the reciprocating pump.
Range of use
WLW vertical oil-free (corrosion-resistant) reciprocating vacuum pump is the upgraded product to replace W horizontal vacuum pump, and the principal equipment to obtain rough vacuum. As adopt the full sealing device, it realizes the complete isolation of the crankcase from the cylinder; in addition, self-lubricating materials are used for piston ring to achieve the advanced oil-free lubrication. Since no sewage is discharged, this type of vacuum pump is especially suitable for the vacuum distillation, vacuum evaporation, vacuum drying, vacuum concentration, vacuum impregnation, and other processes in chemical, medicine, food and other industries.
(1) Small power consumption and significant energy-saving effect; (2) Small floor space and low working noise; (3) Cylinder adopts forced water cooling with good cooling effect; (4) Adopt advanced sealing structure to put an end to oil splash; (5) Due to the rational structure and uniform stress of each moving part, the service life is extended.