How should shielded pumps be maintained when not in use for extended periods?
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This post was last edited by Guan Gongyu on 2015-8-14 at 16:17. How should a canned motor pump be maintained when it is not in use for an extended period of time? As the title suggests: we have 2 shielded pumps. Since the intermediate buffer tank is not used for long periods of time and is only utilized during operation, its extraction pump has never been used. Since there is no material in this intermediate buffer tank, the shielded pump cannot operate either. Question ； This pump hasn’t been in use for 2 years now; it shouldn’t have any impact on the pump body, right? ? How needs it to be maintained? ?
The liquid inside the pump must be completely drained, all inlet and outlet valves should be closed, and nitrogen should be introduced for protection.
Well, it’s sealed with nitrogen. Tank-type micro-positive pressure, connected to the pump body. What about the others? ? Won’t it damage the pump shaft? Or a bushing? I’m not very familiar with the internal components.
There are 2 questions: Is the nitrogen pressure always kept at a positive level? Can you guarantee that the pump interior is replaced very cleanly? Under normal circumstances, if a canned motor pump has been out of use for more than 1 year, it needs to be disassembled and inspected before being used again; at the same time, the motor’s insulation and the balance of the three phases must be checked.
Nitrogen pressure retention. The tank is equipped with a pressure gauge. The pump body has been thoroughly cleaned, and nitrogen has been used to purge it into the underground tank. We are C4 materials, and they are easy to clean. You’re absolutely right about what you said later; we don’t know anything about the other types of maintenance for pumps. It’s also unclear whether it will get damaged if left unused for a long time.
It won’t get damaged, but it’s fine to take it apart for inspection before starting.
The bearings of shielded pumps are sliding bearings, which are mainly lubricated by the medium being transported. The gap between the rotor shield and the stator shield is small; it is essential to ensure that all process media are completely removed to prevent crystallization. Additionally, the cooling water supply must be shut off and the cooling water drained thoroughly. As mentioned above, these measures should prevent any damage, but it is necessary to rotate the shaft during startup to check whether it moves smoothly. If there is any sticking, the shaft needs to be disassembled for inspection. While driving, pay attention to ensure that the bearing monitor is in the green zone.
Rotate the impeller at the pump inlet to turn the shaft