Frequent damage to centrifugal pump bearings
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I’m seeking advice from everyone. We have a centrifugal pump that uses 1% saline as the fluid. However, the bearings on the side of the pump head are failing frequently, and the bearing caps on that side are also worn out. The bearings on the side near the motor, on the other hand, seem to be fine. Could anyone tell me what might be causing this issue?
Please check the following: 1. Lubricant issues: Are there any problems with the quality and level of oil in the bearing housing? Has the lubricant not been replaced on a regular basis, and is it dirty? The oil level should be at least at the level of the center of the lowest ball, but it shouldn’t be too high either, to prevent overheating； 2. Mechanical damage: Whether there is wear between the impeller collar and the pump body collar, whether there is excessive vibration during operation (due to poor impeller balance), and whether the shaft is bent ； 3. Axial force: If this condition persists from the moment the new pump is put into use, it is likely that there is an issue with the balance of the axial force on the impeller (this is merely a speculation, as the installation structure of the bearing housing is not known). The excessive forward axial force is the cause of this problem, and the manufacturer should be contacted to address it. If the new pump does not have this issue but the old pump does, then this point can be ignored. Based on the oil stains on the cover in the picture, if the oil in pumps that are not having any problems also looks like this, it’s likely due to the failure to replace the lubricant over an extended period of time
It would be good to add another panoramic view, so that one can see what the pump looks like and understand what the structure of the so-called pump head and pump tail is. Also, it is necessary to check whether the use of production materials meets the requirements of the pump. For example, the density, viscosity, and sediment content of the material, etc. Mechanical technicians performing maintenance pay attention not only to the mechanical damage to the equipment itself, but also to whether the manufacturing processes and operating procedures comply with relevant regulations. For reference.
Equipment maintenance and equipment assembly issues are just one aspect. Process operating conditions and medium parameters are also very important
The pump is not short of oil; the lubricant has only been in use for less than two months, and there is no friction on the seal rings. As for whether the pump shaft is bent, this has not been checked. This is a new pump that has been in use for less than a year, and pumps of the same model have all suffered from damage to the bearings on the pump side
It is saltwater at a 1% concentration, with basically no impurities, and it does not operate at an excessive flow rate when in use
The medium is a saltwater solution with a concentration of about 1%, similar to plain water
The gland is also worn out; it’s very likely that there is a problem with the pump’s clearance. It is also recommended to pay attention to the pump’s operating temperature, especially in the area around the volute, to check for any signs of cavitation
This should not happen with the new pump. Was there a problem with aligning the coupling during installation? Is there significant vibration when the machine is turned on? The bearing is running on the inner circle; the shaft needs to be repaired. If not repaired, either a new bearing will be needed or it will still break. Whether the spindle is deformed, and the dynamic balance of the impeller.