Water ring vacuum pump (also known as liquid ring vacuum pump).It is a kind of rough vacuum pump, it can get the limit of vacuum is 2000 ~ 4000 pa, Equiped with air ejector can reach 270 ~ 270.Liquid ring vacuum pump can also be used for compressor, called water ring compressor, belongs to low pressure compressor, the pressure range of 1 ~ 2 x 105 pa gauge pressure.Originally used as water ring pump self-priming pump, and then gradually used in petroleum, chemical industry, machinery, mining, light industry, medicine and food and many other industries.In many industrial production process, such as vacuum filter, vacuum water diversion, vacuum feed, vacuum evaporation, vacuum concentration, vacuum resurgence and vacuum degassing, water ring pump is widely used.
Due to the rapid development of vacuum technology, water ring vacuum pump in rough vacuum obtain aspect has been paid great attention by people.Because water ring pump in the gas compression is isothermal, so can pumping flammable, explosive gas, it also can smoke in addition to the dust, water, gas, therefore, water ring pump application is increasing.In the pump body is equipped with the right amount of water as working fluid.When the impeller rotates clockwise and impeller water to be thrown around, due to the effect of centrifugal force, water creates a decision in the pump cavity shape similar to the thickness of the closed circle, etc.Water ring surface of the lower part coincided with the impeller wheel tangent, water ring on the division of surface just contact with the top of the blade in water ring (actually leaves insertion depth).As the impeller wheel hub with a crescent-shaped space formed between water ring, and the space was divided into impeller and blade number equal to a number of small cavity.If the bottom of the impeller 0 ° as starting point, so in front of the rotating impeller 180 ° when small cavity volume changes from small to big, and with suction mouth on the face, the gas is inhaled, when the suction at the end of the small cavity is isolated from the rest of inspiratory mouth;When the impeller to rotate, small cavity from large to small, make the gas is compressed;When small cavity with vent gas was discharge pump.To sum up, the water ring vacuum pump is accomplished by the change of the pump cavity volume of suction, compression and exhaust, so it belongs to the variable capacitance type vacuum pump.
Rotary vane vacuum pump, it has to install in the rotor cavity of the stator and the rotor slot of two or several rotary vane, the rotor and the pump shell surface tangent or intersect, rotor turns the rotary vane, rotary vane by centrifugal force, and some spring force, close to the cylinder wall, divided the inlet and exhaust ports and cyclical expand the inhale, and make the air intake cavity container is periodically to reduce the exhaust volume and compressed gas, borrow pushed aside exhaust valve exhaust gas and oil pressure and vacuum is achieved.
Double pump is composed of two series single stage, when the inlet pressure is high, large and medium-sized general pump, secondary can exhaust at the same time, low inlet pressure, gas by advanced into the lower, and then discharge pump.Due to the change of pump is the use of inspiratory volume to pump gas, its nominal pumping speed can be designed according to inhale the geometric volume calculation.
Roots vacuum pump in the pump cavity, there are two “8” glyph of rotor, roots vacuum pump need backing pump.The limits of roots pump vacuum besides depending on the pump itself structure and manufacturing precision, also depends on the limit of vacuum pump before.In order to improve the limiting vacuum pump, roots pump series can be used.The working principle of roots pump and roots blower are similar.Due to the constant rotation of the rotor, in the smoke gas from the air inlet into the space between the rotor and the pump shell, and then through the vent discharge.Because after inhaling space is closed state, so in the pump cavity gas without compression and expansion.But when the edge at the top of the rotor turning vent, space and exhaust side are interlinked, because of the exhaust gas pressure is higher, is part of the gas recoil into space, make the gas pressure increases suddenly.When the rotor continues to turn, the gas discharge pump.