📏 Pipe Thermal Expansion & Flexibility

Compute thermal expansion ΔL, stress, anchor forces, and expansion loop requirements for carbon steel, stainless steel, HDPE, and copper pipes per ASME B31.3.

📝 Configuration

🔧 Pipe & Material
🌡️ Temperatures & Boundary
Key Equations:
ΔL = α·L·ΔT
σ = E·α·ΔT (fixed)
SA = f·(1.25·Sc + 0.25·Sh)
L_loop = √(3·E·OD·ΔL/SA)

📊 Results

Configure inputs and click Compute.

📘 Methodology

Thermal Expansion

Free expansion ΔL = α·L·ΔT, where α is the material's coefficient of thermal expansion. For constrained pipes (both ends anchored), the restrained thermal stress is σ = E·α·ΔT.

ASME B31.3 Allowable

The allowable displacement stress range SA = f·(1.25·Sc + 0.25·Sh), where Sc and Sh are basic allowable stresses at cold and hot temperatures, and f is the stress range reduction factor for cyclic conditions.

Expansion Loops

When σ exceeds SA, an expansion loop or expansion joint is required. The approximate loop leg length is L_loop = √(3·E·D·ΔL/SA). For critical applications, formal flexibility analysis per B31.3 Appendix D is recommended.