Heat Exchanger, Coil & Radiator Manufacturing calculator
Tube Expansion Time Calculator
Use this calculator to convert a tube expansion workload into adjusted hours. It helps production planners schedule expanders, operators, fixtures, and downstream brazing or leak test capacity.
What this calculator does
- Estimate adjusted tube expansion time for finned coils and tube bundles from tubes to expand, expansion rate, and allowance.
- Use it when mechanical expansion, bullet expansion, mandrel expansion, or roll expansion needs to be scheduled before brazing, leak testing, or final assembly.
- Converts tube count, expansion rate, and allowance into adjusted expansion hours for coil or tube bundle production.
Formula used
- Base tube expansion hours = tubes to expand ÷ expansion rate
- Adjusted tube expansion hours = base tube expansion hours × allowance factor
Inputs explained
- Tubes to expand: undefined
- Expansion rate: undefined
- Expansion allowance: undefined
How to use the result
- Use it to schedule expansion equipment, support labor planning, and check whether expanded cores will reach brazing or assembly on time.
- It does not model tube diameter changes, wall thickness, fin collar fit, lubricant issues, expander wear, or re-expansion after defects.
Common questions
- What is the expansion rate? It is the number of tubes the process can expand per hour on a similar core or tube bundle, including normal handling between passes.
- Should rejected tubes be included? Include expected rework or rejects in the tube count or allowance if they consume expansion time before the part can move forward.
- How does this help the schedule? The adjusted hours show whether expansion is likely to feed brazing, welding, leak testing, or final assembly without creating a queue.
- When should I update the allowance? Update it when tube alloy, diameter, wall thickness, fin pack depth, expander tooling, or operator experience changes from the historical basis.
Last reviewed 2026-05-12.