Expansion Joint Selector
Calculate how much your pipe grows between anchors, the pressure thrust your anchors must hold, and which expansion joint type fits your temperature, pressure, and media.
Operating Conditions
Get a sized quotation for this line
Our engineers confirm movement, pressure rating, and face-to-face length, then quote the joint.
How it is calculated
Axial growth between two fixed anchors follows ΔL = α × L × ΔT, where α is the pipe's mean coefficient of thermal expansion, L the anchored length, and ΔT the temperature swing from installation. Expansion uses the rise to max. operating temperature; contraction uses the drop to min. operating temperature. The joint must absorb both.
Anchor pressure thrust is estimated as F = P × π/4 × D² using the nominal bore. The real effective area of a bellows or arch is larger, so treat this as a minimum and use tie rods or main anchors sized by your piping engineer.
Joint ratings and movement capacities are typical values for standard designs. Final selection depends on size, face-to-face length, cycle life, and the exact media. For chemical service, check the elastomer in our Chemical Resistance Guide.
Typical joint limits
| Type | Temp. range | Pressure | Best for |
|---|---|---|---|
| Rubber | -20 to 110 °C | to 16 bar | Water, slurry, pump vibration |
| PTFE bellows | -50 to 200 °C | to 10 bar (derated hot) | Acids, alkalis, solvents |
| PTFE-lined rubber/metal | -20 to 180 °C | to 16 bar | Chemicals with higher pressure or movement |
| Metal bellows | -196 to 600 °C | to 40 bar+ | Steam, hot oil, gas, high temperature |
| Fabric | to 1000 °C | to 0.35 bar | Flue gas ducts, large movement |