How to deal with a vacuum condition in a bottom-reduction pump? ?
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This post was last edited by Catalyzing a Grain on 2013-10-16 at 14:42. The bottom pump has emptied several times recently, which affects normal operations and the quality of the product. We’ve tried several methods, but none of them worked: 1. Starting the backup pump didn’t help either – the backup pump also emptied its contents. 2. Closing the outlet didn’t result in any flow of fluid. 3. Opening the outlet and closing the inlet also didn’t produce any flow. 4. Shutting down the pump and restarting it was ineffective as well. Now we don’t know how to resolve this issue quickly ? ? ?
Try reducing the production load a bit
First, it is necessary to identify the cause; one should not simply switch to a backup pump – an appropriate solution must be found. 1. Is the liquid level at the bottom of the tower not being controlled properly, with the level being too low? It is important to regulate this liquid level properly. It’s also possible that the instruments are faulty, resulting in an incorrect reading of the liquid level, or that the float at the bottom of the tower is stuck and unable to accurately indicate the liquid level. 2. Is the inlet of the pump blocked, such as by the suction pipe or filter screen? This needs to be cleared and unblocked promptly. 3. Is the sealing oil used too light in consistency or in excessive quantity, or is there steam or water leaking into the pump? 4. When evacuating the pump, close the outlet valve tightly and check if there is any pressure. If there is no pressure, it may be a problem with the pump; if there is pressure, slowly open the outlet valve slightly, trying to maintain a certain level of pressure, which in turn ensures a certain amount of fluid being drawn out. If the pressure drops, close the outlet valve again and then open it once more, repeating this process several times. 5. There may be other reasons as well; experts are welcome to add to this list
I agree with the opinion from the 3rd floor. If both pumps fail to deliver the required flow rate, in addition to checking the issues with the pumps themselves, it is also necessary to consider whether there are system-related problems, such as insufficient inlet pressure, blocked inlet pipelines, or gas entering the inlet. The pump outlet can be closed to check whether the pressure on the outlet pressure gauge is normal. If it is not normal, the pump can be refilled and the air inside the pump removed, after which the outlet pressure should be checked again. If that doesn’t work, 1. contact to clean the inlet filter, 2. check whether there is any blockage in the inlet pipeline or if other volatile substances have entered, 3. check the oil sealing injection level to ensure it is not excessive. If it still doesn’t work, contact a blacksmith to disassemble the pump to determine whether it’s a mechanical fault (the likelihood of this being the case is low, presumably).
Agree with the opinion in 2.3.4: strive to increase the yield of atmospheric light oil. Deep drawing of lines 3 and 4 is necessary to ensure that the bottom pump does not get empty
3. Opening the export side and closing the import side doesn’t increase production volume; it seems to be a funk issue:
If air in the pump causes vacuum, the pump can be stopped, the outlet opened, and the oil from the outlet used to push the air back into the inlet, after which the pump can be started again. 6# Mountain Bamboo Shoots
Is that gas still at the inlet?
There are mainly several reasons: 1. Deep drawing of the side lines reduces the residue in the residue oil； 2. Clean the inlet filter or remove it ； 3. Is there any filtering facility at the bottom extraction outlet (inside the tower), as coking may occur and cause blockages? ； 4. It is possible that the pump model is incorrect; a ZE type pump should be used
We mainly focus on asphalt production, so the requirements for side streams are not very high; sometimes it’s even not possible to extract them at a deep level. How significant is the impact of side streams? The filters were cleaned recently, so they shouldn’t be clogged. As for the pump model, it’s been in use for several years now. Sigh...........
Try the following aspects: 1. How is the pump’s seal? Is it the leakage of coolant into the pump body that causes evacuation? 2. Is there line cleaning at the pump inlet? If the sweep valve is not airtight, it can easily become evacuated. 3. If possible, use variable-frequency control for the motor; a lower pump speed makes it less likely to cause evacuation.