Recently many clients to contact us, and their problems in the process of the use of shielding pump ask us, I hope we can help, today small make up of these questions about shielding pump damage judgment based on the knowledge to discuss with you about, the hope can give the customers friends to help and inspire, let people have a deep knowledge of shielding pump. So we can also do in the process of use in the future know, do not hurry, play the biggest role of the shield pump. Shielding pump after a long time of use, the equipment will appear for a variety of reasons, so how should we judge whether the shield pump is damaged?
1. Vibration and noise analysis of the pump
(1) The pump has vibration, and the vibration source comes from the motor part of the two bearings are set, indicating that the bearing has wear, bearing wear should be checked.
(2) Vibration of the pump, noise, TRG gauge indicates low pressure in the red zone, the pump outlet pressure pressure gauge, pump not up indicates pump reversal, need to adjust the power line phase sequence.
(3) The pump has vibration, and the vibration source is from the pump body. The pump pressure is normal when the outlet valve is closed, but the pressure gauge suddenly drops when the valve is opened, and the operating current is lower than the normal value, indicating the pump cavitation state. It is necessary to increase the height of the inlet liquid level to meet the following requirements: device cavitation allowance =1.3× pump cavitation allowance.
2. Analysis and judgment by TRG (bearing detector) indicator
(1) The table indicates in the yellow zone or the red zone (other conditions are normal), indicating that the bearing has been worn out and needs to be replaced.
(2) There is no reaction after the pump is opened, but the outlet pressure, current and other normal, indicating that the table has been damaged, need to replace a new table.
3, by the breakdown of the pump components wear analysis and judgment
(1) The pump body mouth ring and impeller mouth ring are worn, indicating excessive wear of bearing inner diameter, the bearing needs to be replaced.
(2) There is wear between the front cover plate of the impeller and the pump body, indicating excessive wear on the front bearing end face and the bearing needs to be replaced.
(3) The fixed and rotor shielding sleeves are worn, and the bearing inner diameter size does not exceed the limit value, indicating that there is foreign matter entering the motor cavity, check whether the inlet filter is damaged.
(4) The end face of the rear bearing and the thrust plate are worn, while the front bearing and the thrust plate are not worn, indicating that the shaft thrust is backward and the flow may be too large. Check whether the outlet valve is opened too large.
(5) The front bearing end face and thrust plate surface are worn, while the rear bearing and thrust plate are not worn, indicating that the shaft thrust is forward and the shield pump is in a state of liquid shortage. Check whether the inlet filter is blocked, the system is short of liquid supply and the pump is cavitating.
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