Liquid ring vacuum pump troubleshooting treasury of knowledge

一、Vacuum pump degree is not enough

Possible reasons for：Insufficient motor power lead to speed is not enough; inadequate water supply; the gap between the impeller and the distribution plate is too large; mechanical seal leak caused the leakage damaged; impeller wear too much; not circulating water discharge

Elimination methods：
Check supply voltage if it is within the rated motor voltage range; increase supply the amount of water (must be within the control correct range, otherwise it will cause motor overload fever); transfer of small impeller clearance and Port plate (usually 0.15-0.20mm); Replacing the mechanical seal; replace impeller; check the outlet pipe

二、Not start or started and have a big noise

Possible reasons for:The motor supply voltage is not enough ,Motor phaseless running;Pump long time doesn’t use then lead to rust,In the pump suction sundry; Impeller drag port board.

Elimination methods：

Check whether the power supply voltage is too low;check whether the motor wiring are secure;
Check the supply voltage is too low; Check whether the electrical wiring are solid; if the pump useless long can cause corrosion or rust remover add artificially removing rust pump cover open; open pump cover to remove debris; adjust the impeller and port plate distance.

三、motor overheating

Possible reasons for: supply too much water lead to motor overload;Motor phaseless ;discharge port blocked;Impeller drag other components.

Elimination methods：
Reduce the amount of water to the normal range (see pump instructions for use of the amount of fluid); checking the wiring is solid; check the exhaust port; adjust the gap open impeller and pump cover other parts.

四、Insufficient flow

Possible reasons for：Pipeline leak leakage; Resistance losses increased

Elimination methods：Check connections mechanical seals; check pipeline and back valve if have trouble.

Liquid ring vacuum pump routine maintenance

(1)In the normal work should pay attention to inspection and lubrication of the bearing, the temperature (bearings and cylindrical office) than the ambient temperature is usually higher than 15 ℃ ~ 20 ℃ is appropriate, the maximum allowed to exceed 30 ℃ ~ 35 ℃ that the actual temperature at the outer bearing frame should not exceed 55 ℃ ~ 60 ℃; bearing normal working year should refuel 3 to 4 times, bearing at least once a year to clean and replace the lubricant.

(2) during normal operation but also regular compression packing, if the gland packing is worn out and can not guarantee that the required sealing performance, should be replaced with a new  gland packing. If the mechanical seal, found leakage, check the mechanical seal ring is damaged or if the movement auxiliary seal aging, such as the above circumstances, need to be replaced with new parts

(3) in the event of a special sound can be removed two linking piece on the end cover, check whether the two face impeller with splitter grind, also can check whether the exhaust valve plate is normal

Vacuum pump mechanical seal leakage causes:

①、Mechanical seal disassembly inappropriate

When the replacement of non-energy end mechanical seal, found within the assembly seal O-ring on the ring means no good. O-rings should be attached to the outside of the ring seat seal groove, and O-ring assembly review found no such device, but the wrong equipment to the outside of stretched spring positioning pieces that stretched spring deformation, completely not achieve axial static sealing effect, resulting in leak.

②、mechanical seal freeze water pressure is too large .
Machine static ring seal dense book cover affixed by a stretched spring force is imposed on the ring. When freezing water pressure is too large, the water pressure will act on the static ring, as motionless stationary ring is born, thus will stimulate pressure ring, stationary ring in the same position compression springs stretched, thus weakening or cancellation of movement toric contact force, resulting in dense cover leaks. After the overhaul seal leak through into the freezing water to energy end machine, the inlet valve open 2/3 inferior race, complete mechanical seal leak, when the valve is open over than 2/3, mechanical seal emerge leakage. Tripartite (maintenance side, iron motorized division, Sichuan Daewoo mechanical seal build factory) initially concluded that because the water pressure is too large due to the cause, it is proposed to be switched on after the motor Peixiu use, further tracing to identify their true leakage cause.

③、 dynamic and static ring cover broken

This is the main reason causing the number of times before replacement of the pump seal leak.

Energy and non-energy-side end mechanical seal is disassembled in the same shaft, impeller means beside the shaft, the shaft ends of bearing support means vivid. When the joint replacement or energy end energy end mechanical seal, the corresponding end of the bearing (bearing) must be stored in the assembly down capability old mechanical seal, install a new mechanical seal, but this time so the shaft and impeller gravity, lose one end of the bearing support impeller and shaft with conviction collapse down the shaft to the bearing end without skew. Because static ring is not opened at one end with a bolt on the pump cover raw motionless, moving ring is shrouded together vivid shaft and the shaft, the other because the quiet inner ring and the shaft with a small gap, when the shaft staying skew , it will cause: a, movement is not opened at one end of the ring absolute displacement, so that the static ring dense book cover mutual pheasant squeeze, leading to fragmentation; b, the shaft is not opened indirect pressure on the inner end of the stationary ring, causing the stationary ring secret book cover broken or crushed.

After a comprehensive understanding of how many times before replacement operation, so that one end of the replacement is good but on the other side of the machine seal is the cause of the leak is caused by the above ingredients. We actually have the operator of the thought to a problem, just take the wrong steps: how many times before the change is to use winter squash capture disassembling the shaft to prevent shaft of swinging, confirm the lifting steps in the theory of operation is there is a big mistake, especially not suitable for vacuum pump of this kind of heavy machine sealing device. When lifting point, winter squash, tension is difficult to thoroughly grasp well, it is difficult to prevent shaft of swinging.

2 vacuum pump turning causes hardship

①, pump positioned at both ends of the bearing clearance is not adjusted well

The pump bearings are adopted at both ends of the double row tapered roller bearings, double row tapered roller bearing inner and outer rings are two rows of cone contacts the inner ring is capable of binding to the outer ring taken from the outset. There are two columns between a bearing inner ring gap adjusting spacer ring, which is bearing the original clearance by the spacer rings between two columns to grasp the inner ring, the normal bearing factory the gap once adjusted.

Removing the shaft bearing, the inner ring in two columns at the top of a column shaft shoulder, another column back by locking cap retaining the shaft, after locking the inner ring and the retainer ring two columns need not be closely linked to together with the rotation axis of the outer ring and bearing housing tight fit does not move. Then the gap adjustment spacer ring Bohou smaller than the original thickness, when the locking cap back, inner and outer rings to produce two columns incomparable regulation squeezing force, so that the rotation of the bearing rotation hardship or frustration

②、  the bearing inner ring no device in place

Bearing inner ring no means in place will produce the following 1) the problem, the cause is absolute around in outer axial dislocation, resulting in two columns of one of the columns in the inner and outer rings extremely Regulation squeezing force. Remove the energy found in the shaft end of the bearing surface of the device bearing the status of a great eating marks, concluded that the bearing inner ring is not completely integrated into the top of the shaft shoulder, which is the main reason leading to the crank hardship.

③、both ends of the impeller and the pump didn’t adjust the clearance

Water ring vacuum pump impeller gap by moving both end faces at both ends of the bearing to adjust. Adjusting step is between the bearing and the bearing bracket means positioning surface subtraction gasket.

④, mechanical seal ring movement card to help each other after the Secretary of skin breakdown.

Water ring vacuum pump maintenance and daily maintenance

1.Liquid ring vacuum pump maintenance

(1)should always pay attention to the oil level and oil cleanliness, the new pump oil change once work 150 hours, after every February-March oil change once. If the condition is not good, when the vacuum drops, it can shorten the oil change time

(2)pumps and pumping housing should be kept dry and clean

(3)constant attention to the cooling water and oil temperature, the maximum should not exceed 85 ℃, the cooling water inlet temperature does not exceed 30 ℃, the water temperature does not exceed 5 ℃, and keep the water clean

2.routine maintenance precautions

(1)Regularly check the water ring vacuum pump line and the junction with or without loosening. Hand rotating water ring vacuum pumps,and proved the water ring vacuum pump is flexible.

(2)added to the bearing body bearing lubrication oil, observe the oil level should be the subject of centerline oil, lubricating oil should be replaced or supplemented

(3)Remove the water ring vacuum pump diversion drain plug, filling water (or cited pulp)

(4)Close the valve outlet road of  pipeline and outlet pressure gauge and inlet  vacuum gauge.

(5)to move the motor, try to look the motor rotation if it is correct

(6)After starting the motor, when the water ring vacuum pump functioning, open the outlet and inlet water ring vacuum gauge, depending on which shows the proper pressure, and gradually open the valve, and check the motor load conditions.

(7) try to control the water ring vacuum pump flow and head indicated on the label range to ensure that the water ring vacuum pumps operate at maximum efficiency point, to achieve maximum energy savings.

(8)during the water ring vacuum pump operation, the bearing temperature must not exceed the ambient temperature of 35C, the maximum temperature must not exceed 80C.

(9)if found the water ring vacuum pump abnormal sound should stop immediately check the reason

(10) when the water ring vacuum pump to stop use, turn off the valve, pressure gauge, and then stop the motor.

(11) water ring vacuum pump in the first month of work, replacement of oil after 100 hours, after every 500 hours and oil change once.

(12) regularly adjusted packing gland, packing indoor drip ensure normal (with a drip out appropriate).

(13) regularly check the wear sleeve, wear large should be promptly replaced.

(14) water ring vacuum pumps used in the winter season, parking, the need to pump the lower drain plug unscrew the media put the net. Prevent cracking.

（15) water ring vacuum pump stopped for a long time, the pump must be opened entirely, dry moisture, rotating parts and junction are coated with grease packed, properly kept.