I need help determining which electric actuator to use
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Our factory needs to install an electric actuator on a DN100 saturated steam pipeline, with a pressure of less than 1.0 MPA. This actuator is used for venting to the atmosphere; we would like to know what type of actuator would be suitable, as well as what kind of valve body would be appropriate
What material should be used for the valve body? It depends on the temperature of the saturated steam in degrees Celsius If it is below 425°C, WCB material is generally sufficient
The key question I have is: for this electric actuator that vents to the atmosphere, what type of valve should be used – a butterfly valve, a ball valve, or something else?
If it’s a butterfly valve, what type of butterfly valve should be used? Is there a specific name for it?
What is the steam pressure? Forget the butterfly valve; ball valves are more reliable
For the actuators, we use imported switch valves with opening-degree feedback and a hold function
The pressure isn’t high either; it’s below 1.0 MPa. Would a ball valve work? It’s not necessary to open it fully when venting to the atmosphere – analog control will suffice. I’m just trying to figure out what type of valve would be best. A ball valve has indeed been considered, but since it hasn’t been used before, I’m not sure how it will perform. Is it suitable for such operating conditions?
Ordinary carbon steel is sufficient for steam use, but my only concern is that if you use an electric actuator, the steam temperature will definitely be transmitted to the actuator, and I suspect the electrical components inside it won’t be able to withstand 185 degrees℃
That’s true indeed. Do you have any good suggestions?
To be honest, I have never seen a steam vent valve that is an electric valve. Firstly, steam pipes don’t need to be emptied frequently; in most cases, they are emptied only once when steam is first introduced, and there’s no need to do so at other times
A steam vent valve with a DN100 diameter is considered small. Butterfly valves are not recommended, and ball valves are even less suitable. Conventionally, GLOBE valves, also known as plug valves, should be used; they come in single-seat or cage types, and the specific choice requires calculation. The valve body is made of carbon steel WCB, while the internal components are made of 316 material with a hardening treatment; due to the high flow velocity during venting, which causes severe erosion, the vent valve must have excellent sealing properties. Pneumatic diaphragm actuators are the preferred choice for actuators due to their simple structure and ease of maintenance. If no air supply is available, electric actuators must be used instead. When it comes to electric valves, attention should be paid to the surrounding temperature and vibration levels; in such cases, a split-type design can be considered.