Product Name: High-Pressure Control Valve

Body style: Globe, Angle, “Z” body

Velocity Controlling Stage: Up to 60, special designs available

Sizes: 1/4-48 Inch

Pressure Ratings: Class 150-4500 LB

Materials: Carbon steel, Chrome-moly Steel, Stainless Steel, Duplex Stainless Steel

End Connection: RF/RTJ End

Bonnet Style: Bolted bonnet, metal, gasket seal body-to-bonnet joint, or pressure seal

Characterisation: Linear, equal %, quick open or custom design

Guiding: Disk stack

Plug Design: Unbalanced, balanced, pressurized seat

Rangeability: Carbon steel, chrome-moly steel, stainless steel, duplex stainless steel Bolting: Ferritic, austenitic

Actuator Type: Single acting pneumatic diaphragm, Double acting pneumatic piston

Temperature Range: -350°F to 1100°F (-196°C to 590°C)

Velocity Control

When the fluid pressure decreases across a control valve, the speed of the fluid increases at the valve's control element. Managing these fluid speeds is a major design consideration when selecting the appropriate control valve technology. High fluid speeds can lead to cavitation, vibration, and erosion, which can quickly damage the valve and the associated pipeline system.

Unique Solution for Cavitation

As the liquid passes through a constricted area of the valve control element, its velocity increases, leading to a drop in local pressure. If the fluid pressure falls below the vapor pressure, vaporization and bubble formation occur. When the fluid exits the control element, its pressure recovers. If this recovery pressure exceeds the vapor pressure of the fluid, the newly formed bubbles collapse or implode, causing cavitation. Symptoms of cavitation include pitting damage on valve components, poor process control, and noise. The Resistance? control design addresses the issue of increased speed, thus eliminating the potential for cavitation.

Solutions for Noise and Vibration

Excessively high fluid speeds can cause uncontrolled noise and pipeline movement, leading to valve and process component failure. In addition to the risk of system trips, noise and vibration can pose health hazards to plant personnel and the surrounding environment.

Design Against Erosion

Erosion of valve linings can be caused by the washing action of the fluid or particles worn from the inlet. This effect is most severe under high pressure and/or high particle concentrations, and the erosion rate increases with higher fluid speeds. Therefore, controlling the speed is crucial to preventing erosion.

Uncontrolled Velocity

Valve leakage can result from seat wear, insufficient actuator sizing, or poor sealing materials. As erosion affects the valve lining, the valve’s capacity changes, making flow control difficult and leading to symptoms such as increased vibration and amplified noise levels. The Resistance? technology restricts the speed of the fluid entering the seat area, minimizing erosive forces and maintaining the valve's effective control over leakage.