What Is a Control Valve?
Control valves are mechanical devices designed to control the flow, pressure, temperature, or liquid level of a fluid in a system. They act as the final control element in a process, influencing the fluid flow based on signals received from controllers. These controllers continuously monitor and adjust the conditions to maintain the desired parameters within the system.Amongst those available at Athenavalve are:
Single seated valve
Self operated pressure control valve
Cage guided control valve
Three way control valves
View our full range of control valves
How Does A Control Valve Work?
By now, it is common knowledge within the process control industry that the control valve serves as the most prevalent final control element. The primary objective of a control valve is to manage the temperature, pressure, level, or flow of a medium while compensating for load disturbances, ensuring that the regulated process variable closely aligns with the predetermined set value. This medium can encompass substances such as water, steam, oil, gas, or other compounds.
In a typical control loop, several components collaborate to maintain control over the process. These include a sensor for detecting process parameters, a transmitter, a control valve, and a controller.
The sensor and transmitter operate as vigilant observers within the loop, constantly monitoring changes in individual parameters like temperature, pressure, or level of the medium. Subsequently, the collected data is transmitted to the controller. Acting as the "brain" of the system, the controller compares the received "process variable" with the predetermined "set point" and generates a corrective signal sent to the control valve. In essence, the control valve, functioning as the final control element, serves as the "hand" in the control loop, thus establishing itself as the most pivotal component in the automatic control system.
Applications of Control Valves
The utilization of control valves in power plants is extensive, with hundreds of valves playing a pivotal role in regulating every facet of plant operations. These control valves are indispensable for optimizing the efficiency of power plants but are often exposed to challenging conditions, including high temperatures and abrasive chemicals.
As the demand for renewable power sources and the reduction of carbon emissions continues to rise, the production of high-quality valves becomes increasingly crucial. Athenavalve has pioneered the development of innovative control valves that not only endure high environmental demands but also remain cost-effective. Our valves excel in accurately supporting throttle functions, thereby enhancing the performance of critical operations within power plants.
Moving on to petrochemical plants, the petroleum industry is renowned for its global endeavors in oil exploration and extraction. However, its applications extend beyond oil and gas to the production of plastics, dyes, food additives, and various other petrochemicals derived from natural gas, coal, or oil.
Given the extreme temperatures and pressures required in the manufacturing processes, top-notch engineering is imperative for the smooth operation of petrochemical plants. Control valves emerge as critical components in maintaining the system's performance. The chemicals involved in this industry can pose hazards to both the environment and people, underscoring the essential role of system regulation facilitated by control valves.
Types of Control Valves
There are many types of control valves, each designed for specific types of applications.
Butterfly Type(High Performance and Triple Offset)
butterfly motorized valve
Generally speaking, butterfly control valves refer to high-performance butterfly valves (double eccentric butterfly valves) and triple eccentric butterfly valves (triple offset butterfly valves).
The butterfly valve has the same basic functions as other types of control valves, but often has more safety features and is more efficient. The use of butterfly valves in your application can reduce maintenance costs, improve flow control accuracy, and reduce leakage risks. In addition to controlling water treatment plants, butterfly valves provide the best seal and can withstand water pressure. Butterfly control valves are especially effective in large-diameter pipelines.
Reduced Trim Full Ball Valve
Reduced trim full ball valves have a triangular window on the ball side.
When oversized ball control valves are discovered after a plant has been started, reduced trim ball valves are frequently used, not for initial selection and sizing. Due to the larger capacity than the process needs, a reduced trim full ball valve would be the best solution if you cannot alter the piping to accommodate the smaller size valve and the necessary piping reducers.
To simulate the inherent flow characteristics of EQ%, most flow path windows are triangular or V-shaped. The width of the window determines the maximum flow capacity of the control valve.
Globe Type Control Valve
Control valves are characterized by their spherical form, and their ports vary depending on the type of control they provide. Globe control valves are classified as 2-way control valves, 3-way mixing control valves, and 3-way diverting control valves based on their ports.
V-Port or Segment Ball Valve
In many industries, ball valves are widely used because of their low cost, durability, and excellent closing performance. V-ports or segmented balls are the most common types of ball control valves. In flow control applications requiring high precision and control sensitivity, they are less effective than butterfly valves. For this reason, the ball valve requires high torque to open and close, which makes fine adjustments difficult. Fluid control applications are also complicated by the gap between the stem and the ball, which makes finding a specific flow rate difficult.
Eccentric Plug Control Valve
The eccentric rotary valve represents a pioneering technological advancement that blends the robustness, compact design, and extended stem seal life characteristic of globe valves with the virtues of simplicity and reliability.
Eccentric plug rotary control valves feature a dual offset construction design. Firstly, the shaft is positioned behind the valve seat, and secondly, the shaft is offset from the centerline of the valve.
During the initial movement of the valve shaft and plug in the eccentric plug control valve, the plug smoothly moves away from the seat, initiating an open position. Importantly, at this initial stage, there is no friction between the plug and the seat. This design feature enhances the efficiency and longevity of the valve's operation.
Control Valve Advantages
Precision Control
Flexibility
Energy Efficiency
Process Stability
Automation Integration
Safety Enhancement
Reduced Wear and Tear
Environmental Compliance
Cost Savings
Adaptability to Various Industries
Control Valve Disadvantages
Opening and closing is not prompt
The pressure control valve creates vibration.
It is prone to leakage when operated at high temperatures
A large space is required when assembling, starting, and maintaining it
Further Information
At Athenavalve Valve Division, you’ll find various products suited to an array of industrial markets worldwide, including Power Generation, Oil & Gas, Chemical/Petrochemical, and Defense. Athenavalve is an expert manufacturer in control valve manufacturing.
Our range of valves includes Ball Valves, Butterfly Valves, Check Valves, Control Valves, Gate Valves, Globe Valves, Level Gauge,Strainer and Instrumentation Equipment.
more detailed information please visit: https://www.athenavalve.com/what-is-a-control-valve.html