Vacuum filters in concentrators and large water ring vacuum (before starting) all need to use vacuum pumps to extract air from them. Because a vacuum pump is a compressor that sucks gas out of thin air and discharges it into the atmosphere. Generally, the pressure of the gas it sucks out is lower than the atmospheric pressure (the vacuum pump manufactured recently can make the residual pressure in the vessel 1 x 10-15 mm silver column), and the pressure of the gas it exhausts is slightly higher than the atmospheric pressure.
At present, the vacuum pumps used in concentrators are rotary vane vacuum pumps. Rotary vane vacuum pump only sucks air from a certain space (such as air in the filter), and can suck 98% of the air; while wet vane vacuum pump sucks liquid and air together, and can only suck 85% of the air. In order to maintain a certain volume of vacuum pump and discharge heat, water must be continuously circulated. In order to supply water to the vacuum pump, a special water tank connected with the discharge pipe is installed, and a gate valve on the tank is used to regulate the circulating water volume. The used water is put into the box with air. In order to avoid blade end wear, there should be no inclusions in circulating water. Otherwise, the blade will be worn, and the exhaust volume will decrease with the increase of wear. Generally, the wear should not be greater than 0.1 mm.
SV Rotary Vane Vacuum Pump
Rotary Vacuum Pump Working Principle
The rotary vane vacuum pump is mainly composed of stator, rotor, rotary vane, fixed cover, spring and other parts. The structure is composed of a rotor eccentrically mounted in the stator cavity (the clearance between the outer circle of the rotor and the inner surface of the stator is very small) and two rotating plates which slide in the rotor slot and are attached to the inner wall of the stator by spring tension and centrifugal force. When the rotor rotates, it always slides along the inner wall of the stator.
The crescent space enclosed by the rotor, stator cavity and fixed cover is divided into three parts: A, B and C. When the rotor rotates in the graphic direction, the volume of space A connected with the suction port increases continuously, and the pressure of space A decreases continuously. When the pressure in space A is lower than that in the pumped container, according to the gas. The principle of pressure balance is that the exhausted gas is continuously pumped into the suction chamber A, which is in the process of suction. The volume of B-cavity space is gradually decreasing, and the pressure is continuously increasing. At this time, it is in the process of compression. The volume of space C connected with the exhaust port decreases further, and the pressure of space C increases further. When the pressure of the gas is stronger than the exhaust pressure, the compressed gas pushes the exhaust valve open. The pumped gas continuously passes through the oil reservoir in the tank and is discharged into the atmosphere. During the continuous operation of the pump, it continuously sucks. Gas, compression, exhaust process, so as to achieve the purpose of continuous pumping.
The exhaust valve is immersed in oil to prevent the atmosphere from flowing into the pump. Oil enters the pump cavity through the clearance, oil hole and exhaust valve on the pump body, so that all moving surfaces in the pump cavity are covered by oil, forming the seal between the suction cavity and the exhaust cavity. At the same time, oil is filled with all harmful spaces to eliminate their influence on the limit vacuum.