Calculators › Thermal Expansion Calculator
🌡️

Thermal Expansion Calculator

Pipeline Thermal Growth & Stress Analysis

Thermal Expansion Calculator
Calculates pipe length change (ΔL = α × L × ΔT) and thermal stress (σ = E × α × ΔT) due to temperature variations. Uses temperature-dependent expansion coefficients per ASME B31.3 Appendix C. Provides expansion loop sizing guidance and anchor force estimates for constrained systems.

Pipeline Parameters

ft

Temperature Conditions

°F
°F

ΔT is difference from installation temp, not ambient

Constraint Condition

Anchored pipes develop full thermal stress; guided pipes allow axial movement

Pipe Dimensions (Optional)

in
in

Enter for anchor force and expansion loop calculations

📚 Learn the Theory

Comprehensive coverage of linear and volumetric expansion, expansion coefficients, thermal stress analysis, and expansion loop design per ASME B31.

Read Engineering Guide → Pipe Stress Analysis →

Formulas

ΔL = α × L × ΔT
ΔL = Length change (in)
α = Expansion coefficient (in/in/°F)
L = Pipe length (in)
ΔT = Temperature change (°F)
σ = E × α × ΔT
σ = Thermal stress (psi)
E = Modulus of elasticity (psi)

Quick Reference

Carbon Steel Rule of Thumb:
~0.78 in expansion per 100 ft per 100°F
Material α (×10⁻⁶/°F)
Carbon Steel6.5
SS 3049.6
Aluminum13.0
HDPE80.0

Standards & References

  • ASME B31.3
    Process Piping - Thermal Expansion and Flexibility Analysis
  • ASME B31.8
    Gas Transmission and Distribution Piping Systems
  • MSS SP-58
    Pipe Hangers and Supports - Design and Manufacture
  • API 650
    Welded Tanks - Shell Thermal Stress

Engineering Notes

  • Installation temperature matters: ΔT is from installation temp, not ambient—install at mid-range when possible
  • Anchored = maximum stress: Fully restrained pipe develops 188 psi/°F thermal stress (carbon steel)
  • Expansion accommodation: Use expansion loops, bellows joints, or ball joints for movements >1"
  • Buried pipelines: Soil friction provides partial restraint—check longitudinal stress per B31.8
  • Plastic pipe: HDPE/PVC have 5-12× higher expansion than steel—frequent supports required

Related Calculators

⚡

Hoop Stress

Circumferential pipe stress
📐

Bending Stress

Pipe bending analysis
💧

Pipeline Hydraulics

Pressure drop calculations