The oil pump starts automatically, and an alarm is triggered when either pump stops, why?
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Yesterday I encountered a question like this: After the backup lubricating oil pump starts automatically, it was found that stopping either of those pumps would trigger an alarm indicating low transmission oil pressure. What should be done in such a situation? Those who know the answer, please help reply. This post was last edited by 156026692 on 2009-3-3 22:19.]
Is it a pipe leak, or is there a massive leak in the lubrication equipment? To the extent that a single pump cannot meet the oil pressure requirement. Stop the machine for maintenance, check the interlock of each pump, and identify the cause of the problem.
After the backup pump starts operating, the flow rates of both pumps increase. If the oil station is equipped with a self-regulating valve, this valve will open. When one pump stops operating, the delay in the self-regulating valve’s ability to adjust may cause the system’s oil pressure to drop to the shutdown level. In the absence of a self-regulating valve, an increase in flow rate causes the safety valve to activate; when one pump is shut down, the delay in the safety valve returning to its normal position also results in the system oil pressure dropping to the shutdown level. In short, after the standby pump starts operating, slowly close the outlet valve until the system pump is shut down, and then fully open the outlet valve for standby use.
In the absence of pipeline leaks, I think it’s likely that the pressure generated by a single pump is not sufficient; both pumps should be used simultaneously. If one wants to use only one pump, then another pump that meets the pressure requirements can be used instead.
I think it’s caused by the pipeline valves; I agree with what was said on the second floor
The issue arises because the pipeline control valve opens up after the oil pump starts automatically, while the standby pump closes later; it would be sufficient to find a way to close the control valve first, and then shut down the standby pump. When the oil temperature is too high, the pressure drops and the standby pump starts; once the oil temperature returns to normal, the pump can be stopped ；
There is another reason: to check whether the pressure transmitter and its circuit are functioning properly
The answer on the third floor is quite accurate; if there is no oil leakage, it could be a delay in the self-acting valve or safety valve, or an internal short circuit in the oil circuit of the control oil system, which causes the speed control oil to lose pressure slowly through the return line. Another possibility is a problem with the instrument’s pressure indication. To resolve the issue, check the control oil return sight glass and the pump outlet safety valve return sight glass, service the check valve, and inspect the instrument interlocks.
1. When a pump is shut down, the system oil pressure is likely to drop to the shutdown level due to the lag in the recovery of the self-regulating valve. 2. It is also possible that the oil pressure control valves at each lubrication point are set too wide open, resulting in the pipeline oil pressure not being able to be maintained. 3. If there are no issues with the two reasons mentioned above and there is no pipeline leakage, I think it’s likely that the flow rate and pressure of a single pump do not meet the requirements; therefore, both pumps should be operated simultaneously. One of the units in our factory is in this situation; after various checks, it was determined that the flow rate of the oil pump was insufficient. SHENGU replaced two oil pumps and two motors for us at no cost.
The check valve at the pump outlet is leaking severely; it should be repaired.