Estimate tightening torque from a thread specification with explicit assumptions

A diameter does not define tightening torque

An “M10” note is insufficient for selecting assembly torque. Confirm pitch, material, strength requirements, lubrication, joint purpose, and existing assembly instructions. Geometry lookup and preload-related torque estimation answer different questions. Check manufacturer instructions before applying a generic estimate.

Record the evidence behind each input

1. Confirm the complete thread form and specification from drawings, markings, and process documents.
2. Use Thread Torque Master to look up dimensions and tolerance ranges, comparing them with the drawing and applicable standard.
3. Record material and operating conditions. Mark unknowns rather than presenting defaults as measured data.
4. Retain input values, result, units, and assumptions. Compare conditions through separate calculations.
5. Have the responsible engineer reconcile the estimate with the assembly process and required validation.

An illustrative sensitivity calculation

For teaching only, use T = KFd. Assuming preload F = 10,000 N, nominal diameter d = 0.010 m, and factor K = 0.20 gives T = 20 N·m. Changing only K to 0.15 gives 15 N·m. These are not recommended M10 torque values or a statement of the app’s internal algorithm. They illustrate why a precise number without justified conditions may be unusable.

Accept a reproducible record

Another engineer should be able to reproduce the lookup and estimate and distinguish drawing data, manufacturer information, and assumptions. Check units and missing pitch or material information. Acceptance means the estimate is explainable and further validation requirements are visible, not that production assembly has been authorized.

Scope

The store lists dimensional lookup, torque calculation using specification, material, and conditions, and national/international standard comparison. This does not imply automatic friction measurement, physical strength verification, or assembly certification. Critical joints require applicable standards and a validated assembly process; check standard editions separately.

Source: Apple App Store: Thread Torque Master 1.0.