The support bearing came apart again 1 month after the bearings of the 500KW pump were replaced; what could be the reason?
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I invite all experts to discuss this – there are no issues with the bearing installation. The original ones had steel retainers, and I replaced them with steel retainers a month ago as well – both sets have fallen apart. In February, a total of 3 were replaced. All 3 units originally had steel retainers; during the maintenance in February, one unit had its retainer replaced with a copper one, and to date there have been no issues regarding noise, vibration, or temperature. The other two units have steel retainers; from the moment the pumps started operating, their sound was not as good as that of those with copper retainers. On March 6th, one of them was overhauled again; it had already fallen apart. But this time it’s been changed to copper as well; I’m not sure what will happen this time. Also, none of these pumps have oil slinger rings in their bearing housings.
Complete the device information； Let’s clarify again whether it’s a newly installed pump Process medium? Process parameters? The operation process – these will help everyone analyze it for you
The unit started operation in November last year, and by February the bearings began to fail. After replacing it once, it worked for a month before failing again. The medium of the pump is water and powder. Rated flow rate: 2100 m3/h. Rotation speed: 1481 rpm. The impeller diameter is 558 mm.
Factors to consider: 1. Choose manufacturers with reliable quality, such as SKF, NSK, etc； 2. The clearance data for the bearing model must be selected in strict accordance with the manufacturer’s requirements ； 3. The installation quality must comply with the technical requirements of the bearing manufacturer
If possible, please provide the actual flow rate, pressure, and temperature during the operation of the pump. Faults of this type should not be attributed solely to issues with the equipment itself
The pressure and flow rates during actual operation are unknown; the temperature is between 50 and 60 degrees Celsius. The vibration is between 1.2 mm/s and 2.2 mm/s. The horizontal direction is larger than the vertical direction.
I just tested the unit that was repaired yesterday this morning (the support bearing cage is made of copper). Upon startup, the vibration on the drive side is 0.3 mm/s in the vertical direction and 0.8 mm/s in the horizontal direction. 0.4 mm/s vertically and 0.7 mm/s horizontally on the non-driving side. Outlet pressure: 1.4 Mpa. After running for two hours, the temperature at the drive side was 58°C, with a horizontal vibration of 1.0 mm/s and a vertical vibration of 0.4 mm/s. Temperature on the non-driven side: 54°C; horizontal vibration: 0.9 mm/s, vertical vibration: 0.5 mm/s.
It is recommended to send a few photos of the device, including a panoramic view and images of the areas where lubrication takes place, so that we can see what it looks like and facilitate discussion. Based on the description, there are two possible explanations for now; one is a usage issue ； The second is the material issue. It would be best to get some pictures of the equipment on site as well.
From the perspective of operating parameters, these parameters are also normal. Based on the information you provided, there are a few questions: 1. Is the image you attached related to this pump? The diagram shows that the pump’s head is 80 meters, the rated flow rate is 600 m3/h, and the density of the fluid is 720 kg/m3. Please confirm this. Was it the wrong pump chosen, or was it used for another purpose? 2. According to your description, is the outlet pressure of the pump 1.4 Mpa and the inlet pressure 0.5 Mpa? 3. How much is the actual output? You can check the outlet flow meter; if there is no flow meter, it can be calculated based on the current. If you have any questions, you can also add me as a friend to communicate privately
This diagram is from the equipment specifications; the pump is the one used here. The medium is water and powder