The shielded pump does not operate
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The weather has turned cold, the pressure in the ammonia tank is low; I started the booster pump, but it still won’t start. The pump has a flow rate of 1 cubic meter and a head of 80 meters. Strangely, the inlet pipe diameter is 25, while that of the pump inlet is 50; I’m not sure if this is the reason for vaporization at the inlet.
The piping is truly of high quality; the diameter of the inlet pipe must not be smaller than that of the pump’s inlet pipe
When you say the temperature is too low, do you mean that the pump worked properly when the temperature was higher in the past? It indicates that although there are issues with the piping, they are not the root cause of this incident; is there a possibility of crystalline blockages inside the pipes? What is the pressure in the ammonia tank? Open all valves from the ammonia tank to the pump outlet. When the pump is stopped, can the pressure at the pump outlet balance with the pressure in the ammonia tank?
1 The inlet pipeline is defective. 2. Check the steering. 3. Check the opening degree of the pipeline valves. 4 Check how low the feed temperature is. 5 Check for phase loss. Check the speed, current, and so on
It’s getting cold, and the saturation pressure of the ammonia tank has dropped. This pump has not been turned on since it was installed; the pipes are unobstructed. It is winter now, and the pressure in the ammonia tank is low, so pressure needs to be increased before the pump can be started.
Check whether the installation height of the liquid ammonia pump and the pressure drop in the inlet pipeline meet the required net positive suction head of the pump
The ammonia supply pump is designed as a metering pump; each time it is started, it is difficult to increase the flow rate. The stroke needs to be set to its maximum value, and it takes several hours of operation with the return flow closed before pressure can be increased. I would like to ask the experts: for an ammonia supply pump with a capacity of 1 cubic meter, which type of pump can achieve rapid flow rate increase and is easy to adjust? The amount of liquid ammonia used after vaporization varies depending on the user.
You are using a canned motor pump on site; the reason for the inability to build pressure is likely cavitation. Whether pressure can be built depends on the specific circumstances. Is there pressure with the outlet valve closed? Or, if there is pressure at this time, it can be manually switched on; if there is no pressure even when the valve is closed, it indicates system cavitation, which is far from sufficient for the pump to function properly.