Vibration in the boiler feed water pump pipeline

Are there bubbles inside the pipeline? It happened to us once

Check whether the boiler check valve is malfunctioning, and whether the pump is running dry.

Does vibration occur frequently? If it happens only once or a few times, it is most likely cavitation in the feed pump; opening the exhaust valve at the pump outlet to release the vapor inside the pump usually resolves the issue

I also think there is air present; the pipe design allows too many bends, preventing the air from escaping

If the problem persists after ruling out other causes, please check the support structures for the boiler feedwater pipes; this is very important. If the pipe supports or clamps in certain areas are loose or damaged, it can alter the flexibility of the pipes and lead to resonance.

What was said on the sixth floor is correct; pipe supports and hangers are very important. If the stress calculation for supports and hangers is incorrect, or if they are not installed as designed or are not installed properly, it can lead to pipe vibration.

Everyone has covered everything very comprehensively. One additional point: although it’s not common, if all the above measures have been tried and the problem still persists, it is recommended to consider replacing the valve. An inappropriate selection of valve model can also lead to vibration. In some large-diameter pipelines, in order to prevent vibration in the valves – which are naturally quite large-sized – pressure-reducing orifice plates are installed in front of them. This is done to avoid vibrations caused by pressure fluctuations in the valves and other associated equipment. Of course, it’s not appropriate to use such orifice plates in water supply pipelines (where an increase in pressure is actually desired, haha). This is just for reference.

Is that recirculation valve a valve that returns the boiler feedwater at the pump outlet to the deoxidation tank? Generally, there is a flow control orifice plate behind such a valve; we call it a return valve. There is also a pipe on the main pump outlet line, usually quite thin, that leads back to the deoxidation tank. Additionally, there is a check valve on the main pump outlet line – typically, the check valve is located after the recirculation valve, with a globe valve following it. If it is indeed such a valve setup, it’s best to open it before starting the pump. This way, the boiler feedwater in the deoxidation tank can return to the pump due to the difference in pressure, and the gas inside the pump can flow into the deoxidation tank through this pipe. As a result, the pump and the recirculation valve will not vibrate when the pump is started. Another advantage of the recirculation valve is that it prevents the pump from building up too high a pressure, making it safer to start the pump. The flow-limiting orifice plate behind the recirculation valve can affect the pressure at the pump outlet. There are generally standards. It is not possible to use a large orifice plate with a high-pressure pump.

The solutions above are already very comprehensive, so I won’t add anything further!

There are several reasons that can lead to the phenomenon described by the poster: 1. No air release before starting the pump; 2. The temperature of the water in the boiler is too high, resulting in a high vapor content; 3. If the pump body vibrates, it is necessary to inspect the pump or its motor

There are usually two pipelines at the outlet of the boiler feed water pump: one leads back to the deaerator, and the other goes to the steam drum. Before starting the high-pressure feed water pump, the self-circulation manual valve that leads back to the deaerator should be opened. After the pump starts, slowly open the manual valve leading to the steam drum; once things are stable, close the self-circulation manual valve. Give it a try to see if that makes a difference. :) :) :)

There’s absolutely no need to worry about overcurrent! ! !