Finished Tube ID & Torque Calculator
The below calculator can help you determine your finished ID target and recommended torque for expansion.
Calculator
NOTE: The calculated values are estimated based on the available inputs. Actual values may vary due to tube thickness, material, tube sheet thickness, lubrication, operation condition, and/or operator technique. Best practices are to start with a lower torque setting and measure each tube to ensure proper wall reduction and finished ID is achieved.
BWG / Wall Thickness (Inch) Conversion Chart
| Tube Wall BWG | Tube Wall Inches |
|---|---|
| 0 | 0.340 |
| 1 | 0.300 |
| 2 | 0.284 |
| 3 | 0.259 |
| 4 | 0.238 |
| 5 | 0.220 |
| 6 | 0.203 |
| 7 | 0.180 |
| 8 | 0.165 |
| 9 | 0.148 |
| 10 | 0.134 |
| 11 | 0.120 |
| 12 | 0.109 |
| 13 | 0.095 |
| 14 | 0.083 |
| 15 | 0.072 |
| 16 | 0.065 |
| 17 | 0.058 |
| 18 | 0.049 |
| 19 | 0.042 |
| 20 | 0.035 |
| 21 | 0.032 |
| 22 | 0.028 |
| 23 | 0.025 |
| 24 | 0.022 |
| 25 | 0.020 |
| 26 | 0.018 |
Industry Recommended Wall Reductions
| Material | TEMA Standard Target % Wall Reduction | API-660 Target % Wall Reduction |
|---|---|---|
| Aluminum 3003 or 4004 | 4 – 6% | 5 – 7% |
| Aluminum 6061-T | 6 – 9% | 8 – 10% |
| Carbon Steel & low-alloy steel (max 9% Chromium) | 5 – 8% | 8% max* |
| Stainless Steel and high-alloy steel | 5 – 8% | 6% max* |
| Duplex Stainless Steels | 4 – 6% | Not Specified** |
| Titanium (and other nonferrous, work hardening materials) | 4 – 6% | 5% max* |
| Admiralty Brass (and other nonferrous, non-work hardening materials) | 4 – 9% | 8%* |
| Copper & Copper Alloys | 7 – 10% | Not Specified |
Additional Resources
Basic Principles Of Tube Expanding
Tube Expanding is the art of reducing a tube wall by compressing the O.D. of the tube against a fixed container, such as rolling tubes into tube sheets, drums, ferrules or flanges. To assure a proper tube joint, the tube wall must be reduced by a predetermined percentage.
Best Practices For Extending Expander Tool Life
To ensure high-quality tube expansions, the tube wall must be reduced by a predetermined percentage and be consistent with each expansion. In order to complete the job efficiently, it is important to achieve the maximum expander tool life in order to reduce cost and downtime.
Challenges Created Due To Over-Rolling A Tube
A mechanical tube joint is formed when the outer diameter of the tube is compressed against a fixed container. Rolling to the proper wall reduction will decrease the chances of under rolling and over rolling a tube, creating higher quality mechanical joints.
Don’t Overlook The Importance Of A Tube Gauge
Tube Hole Gauges make it easy to accurately measure tube IDs and tube sheet holes found in vessels such as heat exchangers, chillers, and surface condensers.