Valve Accessories

Since , TVI has provided quality valves and accessories to customers around the world. We offer a range of specialized accessories for everything from petrochemicals to pharmaceuticals. With an extensive selection of plastic and metal valves and components, we have what you need for fluid flow optimization. Learn more about our valve accessories below or browse our catalog.

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Actuators

A valve actuator is the mechanism used to open and close a valve. It can be operated manually through the use of a gear, wheel, or lever; however, actuators that require more force often use hydraulic, pneumatic, or electrical power. Actuators can be automated for industrial settings, which is also more efficient and allows remote operation. All actuators from TVI are mounted and tested to ensure optimal operation. Our heavy-duty designs ensure reliable operation and long-term stability. 

Stem Extensions

Valves are controlled through manipulation of valve stems, and a valve stem extension allows for buried valves to operate above ground level. This creates simple access to the valve without having to implement a more arduous solution such as valve pits, man holes, and other alternatives.

Manual Gears

Manual valves are often used to regulate the flow of liquid or gas within a system. In a gear-operated valve, a manually operated wheel or lever is connected to a gear. When the gear turns, it moves a valve disc, which controls the fluid flow. Manual gear valves offer a high level of control and accuracy. Our durable design is made of corrosion-resistant materials that can withstand a broad range of temperatures.

Threaded Lugs

Lug-style butterfly valves used in dead-end service generally have a reduced pressure rating. Lug-style valves are unique because both sides of the valve's body have threaded inserts ' which can be adapted for all types of liquid and constraint.

• 304 & 316 ss available

• Corrosion-resistant

• Dead-end service

• Easy to Install

Locking Devices

Valve locking devices include butterfly valves, ball valves, and sluice valves. They prevent valves from opening during system repairs and maintenance, which helps to ensure worker safety. TVI's valve locking devices incorporate durable, corrosion-resistant designs with an easy-to-use color display. We make our devices easy to install to reduce overhead and keep your operation running smoothly.

Valve Flanges

Valve flanges use bolts, gaskets, and other connectors to seal pipes, valves, and other fluid system components together. Although they may be welded together, removable flange hardware allows for easy maintenance, repair, cleaning, and inspection. TVI offers a wide range of corrosion- and temperature-resistant valve flanges with an exceptionally high degree of design accuracy and durability.

Valve Fasteners

Valve fasteners are the hardware used to connect components at joints in a fluid system. Common valve fasteners include screws, nuts and bolts, and wing nuts. TVI provides a range of valve fasteners in a variety of materials, including metal alloys, PVC, PP, and PVDF. Our valve cover fasteners are easy to use and inexpensive, with a compact, sturdy design and long service life.

Superior Valve Solutions From TVI

For more than three decades, customers have relied on TVI to provide superior fluid control systems and accessories. We continuously expand our relationships with valve manufacturers to meet our customers' needs and increase serving capacity. Contact us today to learn more about our valve accessories and other products. 

CONTROL VALVE ACCESSORIES

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What are control valves?

A control valve is the most commonly used to regulate fluid flow in the process. Control valves are the element controlling the pressure and the flow inside a system or within a process. These mechanical devices are there to control liquids, gasses, vapours, slurry, and so on. Some of the control valves are manual but automatic control valves are also available when the condition and environmental condition is suitable for such units.

To understand the different applications of compressed air and how valves are used, one must first have knowledge of the kinds and types of valves used by industries.

What are different control valve parts?

Depending on the control valve characteristics and its design, some parts differ within the control valve, but the rest is pretty much the same. Control valve positioner, trim, body, etc. are all there within control valves as their basic components. Examples of different control valve types are Gate, Globe, Check, Plug, diaphragm, Ball, Butterfly, pressure relief, etc. Each type has multiple models and each model has different parts with different features and functionalities.

The main goals of different control valve parts:

1. Controlling the flow direction

2. Relieving the system from specific pressures

3. Increasing or decrease the flow

4. Turning the flow on or off

5. Regulating the flow or process pressure

Control Valve Accessories

The following list shows the most commonly used accessories with the control valve, as per the requirements.

1. Pneumatic Positioners

2. I/P Transducers

3. Volume Boosters

4. Position Transmitters

5. Limit Switches

6. Solenoid Valves

7. Air Lock relay

8. Handwheel

I/P Transducer-

A current to pressure uses a converter module that converts a 4 to 20 mA current input to a proportional 3 to 15 psi pressure output.

In some applications, where a high level of positioning accuracy by a positioner is not required. In these applications, an electro-pneumatic (I/P) transducer only can be used.

Position Transmitter-

The purpose of a position transmitter is to provide independent, separate valve position feedback to the control system. Position feedback of the control valve often becomes necessary as it is used for process monitoring, troubleshooting, or startup/shutdown verification from the control room by an operator. The position transmitter is mounted directly to the valve yoke and measures the position of the valve stem or shaft.

Limit Switches

The purpose of a Limit Switch is to provide a discrete open or discrete close input signal to the control system when the valve reaches a specific position within its range of travel.

Limit switches, which are mounted on the control valve and on the yoke are also used for process monitoring, troubleshooting, or startup/shutdown verification from the control room by an operator.

These switches will only provide specific valve position feedback. These can be mounted on the control valve to get additional feedback signals to the DCS or PLC systems as per our requirement.

Valve Positioner:

Valve positioners are devices used to put a valve in the correct position by increasing or decreasing the air load pressure on the actuator. Instead of the process controller sending a signal directly to the actuator to move the valve, a valve positioner senses the exact position of the valve and communicates to the actuator to move the valve.

Valve positioners are usually mounted on the yolk or top casing of a pneumatic actuator (for linear control valves), or near the end of the shaft (for rotary control valves). For either set-up, the positioner is connected mechanically to the valve stem or valve shaft. This allows for the valve's position to be compared with the position requested by the controller.

Advantages of Valve Positioner :

1. Minimizing the effect of friction, hysteresis, and dead band on the valve stem.
2. Enables signal range change.
3. Allows control valve signal reversal: A positioner can operate in either direct or reverse acting mode. In direct acting mode, an increase in control signal pressure causes an increase in positioner output air pressure. In reverse acting mode, an increase in control valve signal pressure causes a decrease in positioner output air pressure.
4. A positioner Increases the speed of response of the actuator.

5. Allows valve flow characteristics to be changed.

6. Allows split range operation. In a split range control loop, one controller output is used to drive two control valves.

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