Convert Millimetres per metre per degree Fahrenheit to ppm per kelvin
Convert Millimetres per metre per degree Fahrenheit (mm/(m·°F)) to ppm per kelvin (ppm/K) instantly and accurately.
Conversion Formula
ppm/K = mm/(m·°F) × 1800
About Millimetres per metre per degree Fahrenheit
The mm/(m·°F) equals 9/5 × 10⁻³ /K ≈1.8 × 10⁻³ /K, combining metric displacement with Fahrenheit temperature. It appears in US-origin pipeline and structural reports where dimensions are given in metres but temperatures in °F. Steel: ≈0.00667 mm/(m·°F); aluminium: ≈0.01283 mm/(m·°F). 1 mm/(m·°F) = 9/5 × 10⁻³ /K.
About ppm per kelvin
The ppm/K (= μm/(m·K) exactly) equals 10⁻⁶ /K and is the universal CTE unit in international materials standards (ISO, EN, DIN). Aluminium: 23.1 ppm/K; steel: ≈12 ppm/K; ordinary glass: ≈9 ppm/K; fused silica: 0.55 ppm/K; Invar: ≈1.2 ppm/K. 1 ppm/K = 10⁻⁶ /K.
Quick Reference Table
| Millimetres per metre per degree Fahrenheit (mm/(m·°F)) | ppm per kelvin (ppm/K) |
|---|---|
| 1 mm/(m·°F) | 1800 ppm/K |
| 2 mm/(m·°F) | 3600 ppm/K |
| 5 mm/(m·°F) | 9000 ppm/K |
| 10 mm/(m·°F) | 18000 ppm/K |
| 25 mm/(m·°F) | 45000 ppm/K |
| 50 mm/(m·°F) | 90000 ppm/K |
| 100 mm/(m·°F) | 180000 ppm/K |