Selection of boiler feedwater control valve

If explosion protection is required on site and a gas source is available, I think a pneumatic diaphragm control valve would be a good choice. Cheap ； If explosion protection is not required on-site and there is no gas supply, an electric version is preferable.

Is the boiler feed water control valve referred to by the poster the main feed water control valve? If so, I recommend choosing a pneumatic option. The reason is that pneumatic diaphragm actuators have a simple structure and require little maintenance. However, I think when selecting this valve, the operator should not focus on the actuator itself; in fact, as long as the actuator meets the torque requirements, there are no other special demands. The key factor in choosing this valve is its pressure resistance and noise reduction capabilities, as the main feedwater control valve has to withstand the maximum pressure difference throughout the process. Therefore, the valve structure and the materials of the valve internals are the key factors in choosing this control valve! Personal opinion! :P

Our factory uses the same type as what the original poster mentioned; we opt for control valves driven by electric actuators.

Using electric control valves can reduce gas supply costs. The boilers in our factory are equipped with Yokogawa Electric products

I agree with the suggestion from the third floor too! ! ! It also depends on what price range you are willing to accept for the valves :) :) :)

Why isn’t there a rating option today? ? ? Have you all noticed?

Domestic pneumatic sleeve valve, with a pressure of 5 MPA and a flow rate of 70 cubic meters; it produces no noise or vibration, and has not required maintenance in 5 years.

I’ve never used an electric control valve before; is it okay to operate it frequently in forward and reverse directions?

A feedwater control valve for a fluidized bed boiler typically consists of two valves: a main feedwater control valve and an auxiliary feedwater control valve. In my opinion, control valves for boiler feedwater should not be driven by pneumatic actuators; instead, electric actuators should be used. This is because, in the event of a malfunction, both pneumatic control valves – whether they operate in an open or closed mode – tend to end up in either the fully open or fully closed position. When fully open, this can lead to an overfilling of the steam drum, resulting in water hammer effects. On the other hand, when fully closed, it can cause a shortage of water in the steam drum, a situation commonly referred to as a \"dry drum\" condition. Neither of these two situations is desirable. When using an electric actuator, there is a control feature in it known as the power-off retention mode; this allows the valve to remain in its position before a failure occurred, even if the electric actuator malfunctions. This prevents excessive fluctuations in the level of liquid in the steam drum, as well as avoiding situations such as water hammer or dry running of the valve. As for the selection of the valve body, the water pressure is high and the temperature is around 105 degrees Celsius during the boiler water filling process. From a field perspective, it is recommended to use butt-welded plunger valves for individuals.

Pneumatic sleeve valves are better, having withstood practical testing. :handshake

1. From the perspective of actuators, both electric and pneumatic types are commonly used and are viable options； 2. From the perspective of the valve itself, a specific calculation and selection must be made taking into account the process conditions (pressure, temperature, flow rate).