Problem of self-priming pump not delivering flow
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The self-priming pump in the oil sump fails to draw in fluid every time it is started these past two days; it turns out that the pump does not have enough water to start pumping. It is necessary to fill the pump before each start-up, and this problem did not occur before. After filling the pump and running it yesterday, the same issue arose again when trying to start it today. What’s going on? (1. We operate the pumps in accordance with standard procedures; when shutting down the pump, we first close the outlet valve. Sometimes, excessive pressure on the pump can cause damage to the pressure gauge, so instead we cut off the power to stop the pump first, and then close the outlet valve. There is a check valve at the outlet ； 2. Gas is released when the filling port of the pump is opened; it’s likely oil and gas. The pump body isn’t hot. Could it be due to the hot weather lately, with temperatures around 35 degrees? Light contamination by oil might cause the pump to fail to draw water ； ）
-It is necessary to check for any leaks, mainly in the inlet pipe.
Learn the normal operating procedures for starting your pumps! Could you say no?
High temperatures can lead to easier vaporization, and using light oil also increases the risk of cavitation. A self-priming pump has a liquid storage chamber; if this chamber often becomes empty, could it be due to corrosion or leaks, or some other issue? Our unit’s self-priming pumps have also experienced problems with insufficient flow rate. However, the manufacturer and the designers determined that the issue was caused by the overly large diameter of the inlet pipeline, which prevented the pump from delivering sufficient flow; therefore, pressure is increased before starting the pump
Check the bottom valve for any leaks or the possibility that it cannot return to its proper position.
There should be no light oil vapors in the contaminated oil; it is necessary to check whether the inlet pipe flanges and the bottom valve are leaking or not sealed properly.
-It is necessary to check for any leaks, as there is little liquid in the reservoir chamber. . .
If it is a sealless self-priming pump, check the solenoid valve at the inlet
1. Is there any air leakage in the piping? 2. Are there any issues with the valves? 3. The performance of the self-priming pump itself. Our self-priming pumps can achieve a suction height of 8 meters and deliver water in zero time; I can prepare a plan for you if needed
Ensure that there is no air leakage at the inlet and outlet flange connections; the pump chamber must be filled with water. Before starting the pump, open the outlet valve to 5%-10% of its full opening, and after starting the pump, gradually increase the opening of the outlet valve while monitoring the pressure gauge. The day before yesterday, after filling the pump, we closed the outlet valve tightly, which prevented water from being drawn in. Later, someone suggested that the outlet valve should be left slightly open; you should give it a try.