Magnetic pumps often fail to start
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The magnetic pump designed by our company for transporting 50% sulfuric acid often fails to operate properly. No abnormalities were found after maintenance of the equipment. Has anyone else encountered a similar issue? The operating conditions are relatively stable; the sulfuric acid concentration may fluctuate, ranging between 40-60%. The outlet pipe is made of carbon steel lined with PTFE, resulting in very low pressure drop.
Please provide the parameters: what is the pump capacity designed for, what is the actual situation in your case, what are the conditions of the inlet pipeline – its diameter and length, the liquid level height, etc. Nothing meaningful is mentioned at all; God only knows where the problem lies
This post was last edited by 3983596_FPPZ on 2019-1-22 at 11:31. The superuser is right – the information provided is indeed too limited to allow for a definite conclusion; I can only offer a rough analysis to help you troubleshoot the issue. There are many reasons why a magnetic pump may not deliver the desired flow rate, and these mainly fall into the following 4 categories. The likelihood of each of these issues occurring in your situation, from highest to lowest, is as follows: 1. The magnetic torque of the magnetic rotor is low from the start, and it cannot meet the torque requirements at high flow rates. This might be due to an excessively high flow rate during operation (no flow meter available), coupled with changes in specific gravity caused by fluctuations in concentration. 2. The magnetic rotor is partially demagnetized, resulting in a torque that is not sufficient for normal operation (check the reasons for demagnetization). 3. Friction between the moving and stationary parts inside the pump leads to an increase in torque ； 4. No liquid at the inlet or poor liquid flow (check the inlet filter) ； 5. Cavitation evacuation (this medium should not experience cavitation). In the first two cases, the impeller rotates at a lower speed; there is some pressure at the outlet, but the flow rate is very low ； In other cases, there is almost no flow pressure at all
Is it a stainless steel magnetic pump or a fluorine-lined magnetic pump? What model? Be more specific?
It’s most likely that demagnetization occurred after rotor slippage
It is likely due to demagnetization of the inner and outer magnetic rotors after overheating.
Does it stop producing output from the very beginning, or only after being used for a while?