Temperature Pressure Ratings Valves

Overview

Engineering reference data for Temperature Pressure Ratings Valves in material science and properties.

Key Formulas

Stress

$\sigma = \frac{F}{A}$

Force per unit area.

Strain

$\varepsilon = \frac{\Delta L}{L_0}$

Change in length per original length.

Hooke's Law

$\sigma = E \varepsilon$

Stress proportional to strain in elastic region.

Thermal Expansion

$\Delta L = \alpha L_0 \Delta T$

Length change due to temperature.

Variables

Symbol	Description	Unit
$\sigma$	Stress	Pa
$\varepsilon$	Strain	—
$E$	Young's modulus	Pa
$\alpha$	Thermal expansion coefficient	1/°C
$\Delta T$	Temperature change	°C

API 6D Pipeline Valve Standards

The API 6D specification establishes pressure-temperature ratings for gate, plug, ball, and check valves used in pipeline service. Ratings are based on valve class, material group, and operating temperature.

Interpolation Between Temperatures

For temperatures between listed values, linear interpolation is recommended:

$P_{interp} = P_1 + (P_2 - P_1) \times \frac{T_{service} - T_1}{T_2 - T_1}$

Where:

• $P_{interp}$ = interpolated pressure rating at service temperature
• $P_1, P_2$ = pressure ratings at tabulated temperatures $T_1$ and $T_2$
• $T_{service}$ = actual operating temperature

Note: Ratings decrease as temperature increases due to reduced material strength at elevated temperatures. Always verify ratings against the specific valve manufacturer's data sheet.

Interactive Charts

References

• Original Source