Spare Parts for Water Ring Vacuum Pump

Water ring pumps were originally used as self-priming pumps. It is composed of impeller, pump body, suction and exhaust disk, water ring formed in the pump body wall, suction port, exhaust port, auxiliary exhaust valve and so on.
Water ring pump system
Water ring pump system (4 sheets)
In many processes of industrial production, such as vacuum filtration, vacuum water diversion, vacuum feeding, vacuum evaporation, vacuum concentration, vacuum regathering and vacuum degassing, water ring pump has been widely used. Because of the rapid development of vacuum application technology, water ring pump has been paid more attention to the crude vacuum acquisition. Because the gas compression in the water ring pump is isothermal, it can remove flammable and explosive gases, in addition to the removal of dust, water containing gas, therefore, the application of water ring pump is increasing.
The pump body is equipped with an appropriate amount of water as the working liquid. When the impeller rotates clockwise, the water is thrown around by the impeller. Due to the centrifugal force, the water forms a closed ring of approximately equal thickness, which is determined by the shape of the pump cavity. The lower inner surface of the water ring is just tangent to the impeller hub, and the upper inner surface of the water ring is just in contact with the top of the blade (in fact, the blade has a certain insertion depth in the water ring). At this point, a crescent-shaped space is formed between the impeller hub and the water ring, and this space is divided into several small cavities equal to the number of blades by the impeller. If the lower part of the impeller 0° as the starting point, then the impeller in the rotation of 180° before the volume of the small cavity from small to large, and connected with the suction port on the end face, at this time the gas is inhaled, when the end of the suction small cavity is isolated from the suction port; When the impeller continues to rotate, the small cavity from large to small, so that the gas is compressed; When the small cavity is connected with the exhaust port, the gas will be discharged from the pump.
To sum up, the water ring pump relies on the change of the pump chamber volume to achieve suction, compression and exhaust, so it belongs to the variable-volume vacuum pump.
The impeller is installed in the pump body eccentrically. When the impeller rotates, the water entering the pump body is thrown around by the impeller. Due to the centrifugal force, the water forms a closed water ring of equal thickness similar to the shape of the pump cavity. The upper inner surface of the water ring is just tangent to the wheel hub of the impeller, and the lower inner surface of the water ring is just in contact with the top of the blade. At this point, a crescent-shaped space is formed between the impeller hub and the water ring, and this space is divided into several small cavities equal to the number of blades by the impeller. If the upper part of the impeller 0 ° as starting point, and then in front of the rotating impeller, 180 °, the small cavity volume gradually changed from small to big, the pressure reduced constantly, and the mines with suction mouth of the suction or discharge tray, when the pressure inside the small cavity space is less than the pressure of the pump container, according to the principle of balance of gas pressure, the gas is pumped continues to be draw in small cavity, is in the process of suction. When the suction is completed with the suction port isolation, from A  to B section, the volume of the small chamber is gradually decreasing, the pressure is increasing, at this time is in the compression process, when the compressed gas reached the exhaust pressure in advance, from the auxiliary exhaust valve in advance. From the sectio, interlinked with vent small cavity volume further decrease the pressure rise further, when the gas pressure is greater than the exhaust pressure, the compressed air to escape from the vent is in the process of the continuous operation of the pump, continuously carrying on the suction, compression, exhaust process, so as to achieve the purpose of continuous extraction.

Advantages
Simple structure, low manufacturing accuracy requirements, easy to process.
Compact structure, high pump revolution, generally can be directly connected with the motor, no reduction device. Therefore, with small structure size, large displacement can be obtained, and the floor area is also small.
Compressed gas is basically isothermal, that is, the temperature of compressed gas changes very little.
Because there is no metal friction surface in the pump cavity, there is no need to lubricate the pump, and the wear is very small. Sealing between rotating parts and fixed parts can be completed directly by water sealing.
Even suction, stable and reliable work, simple operation, convenient maintenance.

Common faults and troubleshooting methods
First, vacuum pump degree is not enough
Possible causes: Insufficient motor power supply leads to insufficient speed. Insufficient water supply; The gap between the impeller and the distribution plate is too large; Mechanical seal damage resulting in water leakage; Impeller wear too much; Circulating water can't be drained.
Elimination method: check whether the power supply voltage is within the rated voltage range of the motor; Increase water supply (must be controlled in the correct range, otherwise it will lead to motor overload heating); Adjust the clearance between impeller and distribution plate (generally 0.15-0.20mm); Replace the mechanical seal; Replace the impeller; Check the water outlet piping.
Two, can not start or start the noise
Possible causes: The power supply voltage of the motor is insufficient. Motor phase failure operation; The pump is not used for a long time, resulting in corrosion; Pump suction debris; Impeller drag distribution plate.
Troubleshooting method: Check whether the power supply voltage is too low; Check whether the motor wiring is firm; If the pump does not lead to corrosion for a long time, you can add a rust remover or open the pump cover to artificially remove rust; Open the pump cover to remove debris; Adjust the distance between impeller and distribution plate.
Three, motor overheating
Possible causes: excessive water supply leads to motor overload; Motor phase loss; The vent is blocked; The impeller drags other parts.
Elimination method: reduce the water supply to the normal range (refer to the pump's operating instructions for liquid supply); Check whether the wiring is firm; Check the exhaust port; Open the pump cover to adjust the clearance between impeller and other parts.
Four, insufficient flow
Possible causes: Pipe leakage; Resistance loss increases;
Elimination method: check the mechanical seal at the joint; Check pipes and check valves for faults.
Regular maintenance
(1) In normal work, attention should be paid to check the working and lubrication of bearings. The temperature (bearing and outer circle) is generally 15ºC ~ 20ºC higher than the ambient temperature, and the highest temperature is not allowed to exceed 30ºC ~ 35ºC, that is, the actual temperature at the outer circle of the bearing frame should not exceed 55ºC ~ 60ºC; The normal working bearings should be refuelled 3 ~ 4 times a year, the bearings should be cleaned at least once a year, and all the lubricating oil should be replaced.
(2) In normal work, the packing should be pressed regularly. If the packing cannot guarantee the required sealing performance due to wear, the new packing should be replaced. If the mechanical seal is used and leakage is found, check whether the static and static ring of the mechanical seal is damaged or the auxiliary seal is aging. In such cases, new parts should be replaced.
(3) In the appearance of special sound, can remove the pressure plate on the two ends of the cover, check whether the two end faces of the impeller and the distributor are damaged, but also check whether the exhaust valve plate is normal.
Selection criteria
1, water ring pump vacuum requirements unit 2, water ring pump pumping speed requirements 3, water ring pump operating conditions 4, water ring pump motor power 5, water ring pump voltage requirements 6, water ring pump material requirements.
Matters needing attention
Remove the
Before disassembly, the water in the pump cavity should be released, and the gas-water separator and suction tube parts should be removed. In the process of disassembly, all the gaskets should be carefully removed. If there is damage, the same gasket should be replaced. The pump shall be removed from the rear end (without coupling or pulley end) in the following order:
(1) Remove the rear shaft bearing cap, loosen the two round nuts with hook hand, remove the bearing seat and bearing;
(2) Loosen the packing gland nut and remove the packing gland;
(3) remove the hexagonal bolt connecting the pump cover and the pump body and the bolt at the bottom foot of the pump cover, remove the back end cover;
(4) remove the pump body;
(5) Loosen the foot bolt at the other end;
(6) remove the coupling and remove the key on the shaft;
(7) Remove the bearing parts before;
(8) Remove the front end cover and remove the shaft and impeller together.
After disassembly, the parts should be coated with oil on the mating surface, thread should also be coated with oil to protect.