Know smoking with reversed flow of qi check valve and vacuum pump are interrelated

A, a reversed flow of qi check valve principle and structure of the rotary vane pump, it has a eccentric loading in rotor and stator cavity rotor slot of two or several rotary vane, the rotor and the pump shell surface tangent or intersection, the rotor turns the rotary vane, rotary vane by centrifugal force, Some spring force) Against the cylinder wall, divided into the vent, and make the air intake cavity container cyclical expand the inspiratory, exhaust volume is compressed gas periodically to narrow, borrow pushed aside exhaust valve exhaust gas and oil pressure and vacuum is achieved. As shown in figure 1. 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 senior people low, 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. Second, the rotary vane pump reversed flow of qi principle and structure as a result of the vacuum pump suction valve is a compression process, so when you have the condensable gases such as water vapor, if before discharge pump cavity reached its saturation vapor pressure, will condense in the oil, make the pump oil emulsification metamorphism, lubrication sealing performance becomes bad, condensation will become new gas in the suction chamber, lower the degree of vacuum. According to introducing, when the water cut of more than 50%, also can destroy the lubrication performance, causing frequent oil change and waste. After 18 years of study abroad, invented the gas ballast pump. Its principle is that the exhaust chamber pressure is by air pressure and steam pressure of two parts, only when the sum of the two is enough to overcome the exhaust valve when the atmospheric pressure and stretch, exhaust occurred. Exhaust gas ballast valve, in before the pump exhaust cavity filled with a certain amount of air, to reduce the exhaust pressure of steam partial pressure, when it is lower than the pump under the temperature of saturated steam pressure, can with filling the gas discharge pump, to avoid condensation in the pump oil. In addition, when sealed pump operation, is mixed with oil in the non-condensable gas condensation or substances in gas phase will dissolve in oil, and escape from the oil in the pump cavity, at this moment if KaiQi town work, also can take in addition to a certain amount of condensable and thus play a role in purification, prolong oil pump life. Vacuum pump oil more expensive, supply of goods is limited, so the rational use of gas ballast has great economic significance. In structure, there is a check valve, preventing exhaust the oil, gas from the air hole, air quantity is designed to be adjustable, can obtain different limit of town gas pressure, gas ballast valve open to move to the appropriate location, outside the pump can realize long-distance operation. Trace permeability gas when the gas ballast valve can reduce noise, also can be used as a vent valve, when the pump is going to stop to avoid or delay the return oil pump. In addition, the exhaust temperature is high, the exhaust temperature of saturated vapor pressure is big, the largest licensing inlet steam pressure is bigger, water vapor allowances is larger. Therefore, when the pump is pumping system contains more water vapor can let pump idling about 20 minutes, to pump again after high temperature smoke system, can avoid or reduce water vapor condensation in the pump. For water pump, pump temperature could be controlled temperature control device in the safe and high numerical range. For example, 150 l/s single-stage rotary vane pump, control pump temperature in 75 + 5 ℃, pump water vapor allowances up to 12 ~ 14 kg/h.