Gas-separation shielded pump
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I would appreciate it if experts could help analyze this: Our gas handling system uses shielded pumps throughout, and these pumps are currently failing quite frequently; as a result, they are all being operated in single-pump mode at present. The cause of the failure was pump cavitation, which damaged the pump. The operation of this pump is characterized by the following: 1. When the pump outlet is opened wider, the increased flow rate can easily cause the pump to overload and stop operating. 2. When the opening of the pump outlet control valve is small, it is easy to cause the medium inside the pump to vaporize and damage the pump. Urgently need a solution, waiting online. . . . . . . . .
Process operation adjustment or process modification
It is recommended to add a return line process; operating things this way will definitely be costly and time-consuming
Thank you. Has anyone done this before? The feasibility of using a pump to pay instead of a pump return line.
I’m completely speechless at such actions!
This post was last edited by 3983596_FPPZ on 2018-11-14 08:01. Device: 1. I think the net positive suction head available for this device is too low, such that even slight adjustments can cause cavitation. Some way should be found to increase the net positive suction head of the unit (by pressurization/cooling/increasing the liquid level in the inlet tank), although it is difficult. Pump: 1. I think the net positive suction head of the canned pump is too high; it fails to meet the cavitation requirements at least at the high-flow and low-flow points. (Regarding the frequent adjustments to the flow rate when placing initial orders, was this due to the supplier’s failure to take this into account during model selection, or was the supplier not informed about it?) 2. It is unknown what the cooling circulation scheme for this pump is; the heat generated by the shielding sleeve of the canned pump can easily cause the medium to vaporize. Is it possible to change the pump’s internal cooling circulation to an external one, so that the heated medium flows back to the inlet tank through external pipes, rather than returning internally to the pump inlet, thereby avoiding cavitation caused by this heat. Operations: 1. Is it possible to adjust the pump’s flow rate by changing process parameters or other aspects of the system, rather than adjusting it directly through the pump itself? 2. I’m not quite sure if the flow rate range of this pump varies greatly? Does it need to be adjusted frequently? I agree with some of the other users’ opinions: instead of adjusting the flow rate at the pump’s outlet valve, it is better to add a return circulation pipe. This way, the pump maintains a basically constant flow rate, and by adjusting the valve on the return pipe, the ultimate discharge flow rate of the pump can be controlled indirectly, thereby minimizing the impact and effects that flow rate adjustments have on the pump.
1. Compare the pump’s parameter sheet to find its maximum flow rate, and install a flow-limiting orifice plate at the outlet to restrict the pump’s flow. 2. Install a low-current protector that can automatically shut down to protect the stator when the opening degree of the inlet valve is too small. 3. Install a temperature protector that will automatically shut down the system when the temperature of the stator coils becomes too high. The above should be able to protect the pump from being damaged as much as possible in case of operational errors.