Convert Percent per degree Fahrenheit to Millimetres per metre per degree Celsius

Convert Percent per degree Fahrenheit (%/°F) to Millimetres per metre per degree Celsius (mm/(m·°C)) instantly and accurately.

Percent per degree Fahrenheit (%/°F)
Millimetres per metre per degree Celsius (mm/(m·°C))

Conversion Formula

mm/(m·°C) = %/°F × 18

About Percent per degree Fahrenheit

The %/°F equals 9/5 × 10⁻² /K ≈ 0.018 /K, the Fahrenheit percent-expansion unit used in US polymer and rubber industry specifications. PTFE: ≈0.0075 %/°F; HDPE: ≈0.0083 %/°F; silicone rubber: ≈0.056 %/°F. 1 %/°F = 9/5 × 10⁻² /K ≈1.8 %/K.

About Millimetres per metre per degree Celsius

The millimetre per metre per degree Celsius (mm/(m·°C)) equals exactly 10⁻³ /K = 1 mm/(m·K), since temperature intervals 1 °C = 1 K (exact). Used in European structural engineering, EN standards, and civil/mechanical design codes for expansion joint sizing. Steel rail: 0.012 mm/(m·°C); aluminium curtain wall: 0.023 mm/(m·°C). 1 mm/(m·°C) = 10⁻³ /K = 1 mm/(m·K).

Quick Reference Table

Percent per degree Fahrenheit (%/°F)Millimetres per metre per degree Celsius (mm/(m·°C))
1 %/°F18 mm/(m·°C)
2 %/°F36 mm/(m·°C)
5 %/°F90 mm/(m·°C)
10 %/°F180 mm/(m·°C)
25 %/°F450 mm/(m·°C)
50 %/°F900 mm/(m·°C)
100 %/°F1800 mm/(m·°C)

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