Overflow issue when starting the feed pump

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The rated current of the power-frequency feed pump is 43.8! At that time, the current reading on the gauge of the feed pump was 43.4. A large machine was started in one of the workshops to alert all other workshops. Soon after, the feed pump stopped operating due to overflow; it’s not clear whether this was caused by an increase in the feed volume or by low voltage resulting from the operation of those other large machines. The outlet of the pump would not open, and when the minimum flow setting was set to two and a half, overflow occurred. When the minimum flow setting was adjusted further, the outlet still wouldn’t open; once the outlet was finally opened, flow occurred at a slow pace, and overflow happened again when the outlet was opened to half its capacity. On the third attempt, the minimum flow rate is not activated; the outlet starts to open slowly. Once the outlet is opened by two notches, the normal processing volume is reached. The current is 43.1, and when it is increased further, over-flow occurs. The voltage during normal operation of the pump at its rated frequency is essentially the rated voltage, with a difference of less than 5%. The current increases as the outlet is opened more – could it be that the actual output power of the pump is too high, causing the starting current to remain high? At present, the outlet of the pump is set at two notches, and the minimum flow rate setting results in oil being trapped; yet the pressure at the pump outlet remains normal. The pump’s rated voltage is 10,000, the current is 43.8; it is a 2-pole motor operating at 2,980 rpm with a power factor of 0.85