Several common use vacuum pumps and its advantages and disadvantages:
1, The chemical industry often use several kinds of vacuum pumps,The common vacuum pump used on the chemical industry can be divided into variable volume simple type vacuum pump and jet vacuum pump, variable displacement pump is the use of the vacuum pump cavity volume to complete the periodic change of the suction and exhaust device, reciprocating vacuum pump, rotary vane vacuum pumps, vacuum pump, water ring vacuum pump, roots vacuum pump is belong to variable displacement type vacuum pump.Jet vacuum pump is the use of venturi effect produced by the pressure drop of the high-speed jet gas transporting to export a momentum transfer pump, water jet vacuum pump and steam jet vacuum pump, soda series jet vacuum pump, combined jet vacuum pump belongs to jet vacuum pump.
2, variable displacement pump work principle and the advantages and disadvantages
(1) the reciprocating vacuum pump, rotary vane vacuum pumps, vacuum pump, roots vacuum pump is to rely on the piston reciprocating motion or rotate the gas suction, compression side by side.Their advantages are put into use new vacuum pump is relatively high, but the pistons are moving parts, so the piston wear cannot be avoided, with the increase of maintenance times work vacuum will continue to decline, until can’t satisfy the production requirements.This kind of pump work noise, fuel consumption, high failure rate is also the fatal shortcomings, need to open a backup a commonly, this virtually increases the equipment investment and running cost.In addition if use this kind of pump suction vapor can non-condensable gas, such as will make lubricating oil emulsification, therefore can only be used in the suction non-condensable gas (air), also can’t pump with granular medium, it also limits its scope of application.
(2) the liquid ring vacuum pump is installed in the pump shell with much of the eccentricity of the rotor rotation, threw the water in the pump shell formation and pump casing concentric rings of water cycle water ring and the rotor blade formed the volume change to gas suction, compression side by side.It has the advantage of low vacuum pumping volume big, can direct suction vapor can non-condensable gas.Its disadvantage is that the vacuum degree is low;Can’t pump with granular media;The rotor high-speed rotation is not easy to do the anti-corrosion treatment, so you can’t pump is corrosive medium.
3, the working principle of jet vacuum pump and the advantages and disadvantages
Jet vacuum pump is the use of venturi effect produced by the pressure drop of the high-speed jet gas transporting to export a momentum transfer pump.It is divided into water jet vacuum pump and steam jet vacuum pump, combination of soda series jet vacuum pump, jet vacuum pump.Jet vacuum pump in the vacuum range, can direct suction vapor can non-condensable gas and with granular medium, simple structure, convenient operation, no moving parts maintenance quantity is small, the advantages of saving energy and reducing consumption is more and more widely used in chemical industry in the operation of each process.