Selecting the right valve is very important for industrial flow systems with respect to efficiency, safety, and precise flow control functionality in process industries. In fluid control applications, actuated valves and control valves are common technical choices because they are used in different applications of fluid control. Knowing their fundamental differences uses, and cost considerations will assist in identifying the most appropriate valve type for your system.
What is an Actuated Valve?
An actuated valve is a valve that is operated by an external device known as an actuator, thus making it non-manual. The actuator is an independent device that is powered by an external energy source like compressed air, hydraulic fluid, or fluid pressure from hydraulic systems, or electricity and converts the control signals into mechanical force to operate the valve body via actuation.
This force acts on the valve stem and causes the valve stem to lift, rotate or shift the valve mechanism to open, close or regulate the flow of fluids in the case of the different types of valves. For example of diaphragm valves, the force acts on the diaphragm’s surface to control flow. The actuator is fitted on the valve and coupled to the internal mechanism of the valve to enable smooth and efficient operation.
Different types of actuators are selected based on application requirements such as speed, thrust force, torque, and control precision. Actuated valves reduce the need for manual operation, increase productivity, and guarantee the stability of the controlled system.
What is a Control Valve?
A control valve is a valve that is used to control the flow rate, pressure or temperature of a fluid in a system, often utilizing control valve actuators for precise adjustments. It controls the size of the fluid passage either by automatic or remote control and regulates the flow of the fluid depending on the signals received from the controller.
When the controller sends a signal, the actuator which is energized by an external power converts the signal into mechanical energy. This force acts on the valve stem and valve plug to alter the size of the orifice in order to regulate the flow of the fluid. The actuator can be adjusted to make small adjustments to the flow rate in order to sustain the required conditions in the system.
A control valve is an essential part of automated fluid control systems because it is designed to change the flow rate in response to control signals in a stable manner.
Key Differences Between Actuated Valves and Control Valves
While both actuated valves and control valves are used for regulating fluid flow, they function differently. Here’s how they compare:
| Feature | Actuated Valve | Control Valve |
| Control Accuracy |
1% – 5% |
0.1% – 1% |
| Response Time | Fast (usually immediate) | Slower, requires fine adjustments |
| Adjustment Capability | Open/Close only (fixed operation) | Gradual adjustments (0%-100%) |
| Application Scenarios | Emergency shutdown systems, fire safety, on/off control | Chemical processing, power generation, temperature control |
| Cost | Lower cost | Higher cost due to complexity |
| Environmental Suitability | Suitable for harsh conditions (high pressure, corrosive) | Suitable for stable controlled environments |
Control Accuracy
Control valves are used for continuous regulation of the flow of fluids and are intended to offer a smooth variation of the flow rate. They are compatible with the electronic control systems, which enable them to be adjusted depending on the system needs, the control precision is usually between 0.1% and 1%.
In contrast, actuated valves are intended to be operated with different types of actuators that can be selected depending on the requirements for speed, force, and the degree of control. The control accuracy of actuated valves is comparatively low, which is about 1% to 5%. Even though they are not as accurate as control valves, actuated valves help to minimize manual operations, increase efficiency, and ensure stability of the system.
Response Time
In many industrial processes, the response time of a valve is an important factor that needs to be considered. Control valves, which are those that change the position of the valve in order to control the flow rate, are generally slower in response. This is because they need to be adjusted to very small increments in order to control the flow, pressure or temperature of the fluids.
On the other hand, actuated valves, including solenoid valves, are of the type that opens or closes fully depending on the signals received. Since they do not require fine tuning, their response time is usually faster than that of control valves.
Adjustment Capability
Control valves are best suited for applications where the flow rate needs to be changed frequently and gradually from fully open to fully closed, from 0% to 100%. They are usually used in conjunction with other control systems like the PID controllers to help in the regulation of pressure and stability.
On the other hand, actuated valves are mainly used for on/off control, and therefore do not have the level of control as the control valves. These valves are usually used in a way that they can only open or close to a particular level of operation, for instance 0%, 50%, 100%. Some of the actuated valves include butterfly valves and ball valves, which although can offer some degree of modulation, their accuracy is much lower than that of control valves.
Application Scenarios
Control valves are used in industries where there is a need to control the flow, pressure and temperature of fluids such as chemical processing, power generation, oil and gas and water treatment industries. In these applications, control valves regulate the system and ensure that it operates at its best by constantly changing its settings. For instance, in chemical plants, the flow rates of control valves can be controlled with a high degree of accuracy, which can be as low as 0.1% of the set point, thus making the plants safe and efficient.
On the other hand, actuated valves, including safety valves and relief valves, are suitable for applications that require on/off control, for instance, ESD systems, fire safety systems, and production lines. These valves are ideal for use in high pressure or in areas where automation is desirable due to the distance from the control room. For example, in an emergency shutdown system, the actuated valves can close within a few seconds, thus avoiding risks and guaranteeing system safety.
Cost Differences
A control valve costs more to purchase and maintain than an actuated valve, as the former comprises more parts and requires intricate adjustments, including the use of actuators, sensors, and even electronic control systems. However, in case your application demands such a level of control, it might be worth looking into.
The choice of the valve depends on the application and the trade-off between the cost of the valve and the degree of control that is required.
How to Choose the Right Valve for Your System Needs
The choice between an actuated valve and a control valve depends on the system that is being used. Here are some of the factors that should be taken into consideration:
Do you need precise control? –If your application requires continuous modulation of flow, pressure, or temperature, control valves, including small valves, are the right choice for their precision.
Is remote operation required? –Pneumatic actuators, electric motor, or hydraulic actuators are ideal for remote or automatic operation of the valves. Pneumatic actuators can provide a large amount of force and are ideal for applications that require quick response times. Electric actuators are ideal for your system if you need high levels of control and compatibility with digital systems. Hydraulic actuators are preferred for high force applications because of their strength and reliability.
What is the pressure and flow requirement? – Control valves are ideal for applications with varying pressure and flow that require precise adjustments, while actuated valves are best used in systems that have constant flow and pressure.
Cost – Actuated valves are cheaper than control valves but the latter provides more accuracy in controlling the flow of the fluid.
Environmental conditions – take into account the conditions that the valve will be exposed to. Actuated valves are designed to work in severe service conditions like high pressure or corrosive services, control valves, though can work in severe services, are more suitable for stable controlled services.
These methods guarantee that you choose the right valve for your application.
Why Choose Vincer Valves for Your System?
Vincer is a trusted company in industrial automation, specializes in electric and pneumatic actuated valves that are accurate, dependable, and of high quality. Vincer has completed over 800 projects and has 30+ certifications and patents, which proves its high level of innovation and quality.
Vincer valves are designed for long lasting use and they work perfectly in the most challenging conditions. Our electric actuated valves integrate effortlessly with control systems which increases automation efficiency. In addition, our pneumatic actuated valves possess rapid response times in under one second.
If you are in need of a high-performance actuated valve for your system, please do not hesitate to contact Vincer and learn how our innovative technology can enhance your system.
Final Thought
In conclusion, it is important to note that an actuated valve and a control valve are two different products that are designed to suit different systems. If the control is to be very accurate and sustained, then a control valve is the most appropriate one. In applications where it is necessary to open or close the valve or automate it from a distance, actuated valves are more effective and economical. Thus, when considering control accuracy, response time, environment, and cost, you can make the right decision to enhance the performance and dependability of your system.