Sunyeh Actuated Valve

An actuator valve, more commonly referred to as an "actuated valve," operates by combining a valve with an actuator. The actuator's purpose is to automatically operate the valve based on received control signals. Here’s a detailed explanation of how actuated valves work:

1. Components of an Actuated Valve

• Valve: This is the mechanical device that controls the flow of fluids (liquids, gases, fluidized solids) by opening, closing, or partially obstructing various passageways.

• Actuator: This device automates the valve's operation. It can be electric, pneumatic, or hydraulic.

2. Types of Actuators

• Electric Actuators: These use electric motors to move the valve stem. They are precise, can be easily integrated with digital control systems, and are suitable for remote operation.

• Pneumatic Actuators: These utilize compressed air to move the valve. They are typically faster than electric actuators and are commonly used in explosive environments due to their inherent safety from lack of electrical components.

• Hydraulic Actuators: These use fluid pressure to move the valve. They are powerful and suitable for large valves or where high force is required.

  
  

3. How the Actuator Works with the Valve

• Signal Reception: The actuator receives a signal from a control system, which could be a simple manual switch f the manual actuator valve or a complex automated industrial control system.

• Signal Conversion: Upon receiving the signal, the actuator converts this into mechanical motion. The type of motion depends on the valve and actuator:

• Linear: Moves in and out, typical of gate or globe valves.

• Rotary: Turns around a shaft, typical of ball or butterfly valves.

• Operation: The actuator moves the valve to the required position:

• Open: Fluid is allowed to pass through.

• Close: Fluid passage is blocked.

• Modulate: The valve is partially opened to regulate the flow rate or pressure.

A valve actuator is a mechanical device that provides the force and motion to operate a valve remotely or automatically, eliminating the need for manual intervention. The primary function of a valve actuator is to open, close, or modulate the valve based on the requirements of the system it serves. This operation is crucial in controlling the flow of fluids such as gases, liquids, or slurries through industrial systems and pipelines.

Actuators come in various types, each suited to specific applications and operational requirements. The most common types include electric, pneumatic, and hydraulic actuators:

1. Electric Actuators: These use electric motors to move the valve stem. They are preferred in environments where precise control is needed and where air supply (for pneumatic actuators) is not readily available. They can be used for both on/off and modulating services.

2. Pneumatic Actuators: These use compressed air to operate the valve, making them highly efficient and suitable for explosive or hazardous environments due to their inherent lack of spark risk.

3. Hydraulic Actuators: Powered by pressurized fluid, they offer extremely high force output for large valve or high-pressure applications.

Each actuator type can be equipped with sensors and controllers that allow for feedback and integration into automated process control systems, enhancing operational efficiency and safety. Valve actuators thus play a vital role in automation, enhancing system responsiveness, and reliability in various industrial applications.

Selecting the right valve actuator is crucial for ensuring efficient, reliable, and safe operation in any flow control system. The selection process involves several important factors that need to be considered to match the actuator with the valve type, application requirements, and environmental conditions. Here's a detailed guide on how to choose the appropriate valve actuator:

1. Valve Type and Operation

• Rotary vs. Linear: Determine whether the valve operates through rotary (e.g., ball, butterfly, plug valves) or linear motion (e.g., gate, globe, diaphragm valves). Rotary actuators are used for rotary valves and typically produce torque to facilitate rotation, whereas linear actuators produce thrust to move valves up and down.

• Operation Requirements: Consider whether the valve needs to be modulated or simply opened/closed. Modulating valves require precise control over valve positioning, suitable for electric or pneumatic actuators with positioners.

  
  

2. Actuator Type

• Electric Actuators: Suitable for precise control and where electrical power is readily available. Ideal for remote locations without access to pneumatic or hydraulic infrastructure. They are also preferable for their ease of integration into digital control systems.

• Pneumatic Actuators: Common in process industries due to their simplicity, reliability, and cost-effectiveness. They require compressed air and are suitable for environments with explosive risks as they do not generate sparks.

• Hydraulic Actuators: Best for applications requiring high force and where size and weight constraints are not critical. Suitable for heavy-duty industrial applications.

  
  

3. Power Source Availability

• Assess the availability of the power source (electricity, compressed air, hydraulic fluid) and its reliability in the facility.

  
  

4. Environmental Conditions

• Explosive or Hazardous Areas: In areas with potential explosive atmospheres, choose actuators certified for these conditions, like pneumatic or specially designed electric actuators.

• Weather Conditions: For outdoor installations, consider actuators that can withstand environmental elements like temperature extremes, humidity, and corrosion.

  
  

5. Safety and Reliability

• Fail-Safe Features: Some applications may require fail-safe mechanisms (e.g., fail-open, fail-close) to maintain safety in case of power loss.

• Frequency of Operation: Consider the durability and wear resistance of the actuator, especially in systems that require frequent operation.

  
  

6. Control and Feedback

• Control Signal Compatibility: Ensure the actuator can interface correctly with the existing control system in terms of signal type (4-20 mA, 0-10 V, etc.).

• Feedback Mechanisms: Actuators with built-in sensors for valve position feedback are essential for applications requiring precise control.

  
  

7. Cost

• Evaluate not only the initial cost but also long-term operational and maintenance costs. Pneumatic actuators, for example, might have lower initial costs but could incur higher operational costs due to the need for compressed air.