Issues regarding the operation of turbine condensate pumps
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The inlet of the turbine condensate pump is under negative pressure; there is a connection line on the inlet pipeline that connects to the gas phase in the inlet tank, thereby balancing the pressure and allowing the condensate to reach the pump inlet. The pump is now running, with the outlet pressure fluctuating continuously; the current also fluctuates as a result. It is inferred that the flow rate is changing erratically, and air has entered the equipment. Apart from the issue of air leakage at the various inlet connections due to the faulty gasket, there is another question: does the line that connects to the gas phase need to be closed after the pump is turned on? Could air be drawn in from the vapor line? I think this situation is similar to a pump with atmospheric pressure at the inlet, where an opening is created in the inlet pipe to connect it to the atmosphere; in that case, air can also easily get in, right?
The balance line is for exhaust; it should be turned off when the pump is started. As for the large fluctuations in flow rate after the pump starts, check to see if your flushing line wasn’t activated before starting the pump.
But our engineering team said they’ve consulted with the design team, and that this line needs to remain operational at all times. I contacted the turbine manufacturer, who also said that this line is open; if there is air leakage from the packing, it needs to be vented through here. But I don’t quite agree; if the filler leaks air, doesn’t it just come out directly from the pump outlet? Will it go back and be discharged through imports? So everyone should share their opinions more
The condensate pump is used to pump condensate; it is usually turned on before starting the pump to ensure that the pump is filled with liquid and to remove any gas from within the pump chamber. It should be turned off after the pump starts operating.
That line is not as you described it; it should be the non-condensable gas vent line at the pump inlet, which leads to the condenser. Its purpose is to remove the non-condensable gases present in the condensate during operation, thereby preventing the pump from running out of fluid
Since the tank is under vacuum, when starting the pump it is necessary to close the outlet valve and use a return pipe to vent air until the pressure indicated by the outlet pressure gauge reaches zero; afterwards, the outlet valve can be slowly opened to the operating pressure, which will prevent vibrations
That pipeline is used to prevent vaporization in the condensate pump. Since the inlet of the condensate pump is connected to the condenser (the condensate water is saturated water at the pressure of the condenser), there is also a negative pressure at the pump inlet, which makes it easy for the condensate water to vaporize there. If such a pipeline is not present, there is no place for the vaporized condensate to be discharged, resulting in the condensate pump failing to draw liquid. Additionally, air may also leak in at the areas where the flanges are not tightly connected, resulting in the pump failing to deliver fluid. This pipeline should remain open during normal operation to allow the discharge of various gases at any time (the standby pump should also remain open so that it can be started promptly). Due to the hydrostatic pressure of the condensate water level in the hot well, the pressure at the inlet of this pipeline and the condensing pump is slightly higher than the pressure in the condenser; however, it remains below atmospheric pressure, meaning it is still a negative pressure. As a result, there is no need for any pumping action to draw in air or vaporized condensate into the condenser.
Thank you all for helping me understand; I get it now. Thanks to everyone