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Control Valve · Glossary

What is Valve Trim?

internal wetted partsControl Valve

Valve trim is the set of internal parts in contact with the flow that control it, such as the plug, seat, cage and stem.

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Valve Trim Explained

Trim sets capacity, characteristic, leakage and resistance to cavitation, flashing and noise. Reduced trims let one body size cover a smaller Cv.

Hardened materials, such as stellite overlays, resist erosion in severe service.

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Calculators for Valve Trim

CalculatorCv Calculator for LiquidsFree online calculator with formula and worked example.CalculatorValve Outlet Velocity CalculatorFree online calculator with formula and worked example.

Free Downloads

Free downloadControl Valve Datasheet Template in Excel with Cv CheckFree download in Excel and PDF.

Frequently Asked Questions

What is Valve Trim?

Valve trim is the set of internal parts in contact with the flow that control it, such as the plug, seat, cage and stem.

What is reduced trim?

A smaller seat and plug in a standard body, giving lower Cv while keeping the line size body.

Why do trims wear?

High velocity, cavitation, flashing and solids erode surfaces, especially near closed.

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All control valve terms · Full glossary A to Z

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