# Boltspan: Joint Design — Preload, torque and fatigue

> Preload, torque and fatigue (iPhone/iPad app by Robert Corbin.)

- Source: https://appshunter.io/ios/app/boltspan-joint-design/id6793156778 (this page in markdown: same URL + `.md`)
- Developer: [Robert Corbin](https://appshunter.io/developer/1890247992)
- Category: Utilities, Productivity
- Price: $3.99
- Age rating: 4+
- Requires: iOS 17.0 · 209 MB
- Released: 2026-08-04
- Data updated: 2026-08-11
- User reviews in markdown: https://appshunter.io/ios/app/boltspan-joint-design/id6793156778/reviews.md

## What is Boltspan?

Boltspan: Joint Design is a focused, fully on-device app. A transparent bolted-joint calculator for preload scatter, torque, joint stiffness, load fraction, separation, proof margin, fatigue, and tightening sequences.

KEY FEATURES
- Metric thread stress-area library
- Torque-preload scatter envelope
- Bolt/joint stiffness model
- Separation and proof margins
- Sequence and inspection worksheet
- Editable complete sample and local project persistence
- CSV input plus local PDF and data export
- Fifty-two original offline reference plates

ONE-TIME AND PRIVATE
- One paid download; no subscription or in-app purchase
- No account, advertising, analytics, tracking, or developer-operated backend
- Core features and bundled content work offline
- Work remains on device unless you deliberately share or export it through an Apple system interface

Engineering screening only. Confirm material, lubrication, thread engagement, embedment, temperature and governing code.


## Version history (last 1 release)

### 1.0 — 2026-08-04

No release notes.

## More apps by Robert Corbin

- [Daily Word Journey](https://appshunter.io/ios/app/daily-word-journey/id6761548266)
- [Hush Secret Text](https://appshunter.io/ios/app/hush-secret-text/id6761658175)
- [Renew Guard](https://appshunter.io/ios/app/renew-guard/id6761755447)
- [Receipt to PDF](https://appshunter.io/ios/app/receipt-to-pdf/id6761782025)
- [Route Your Pay](https://appshunter.io/ios/app/route-your-pay/id6761783719)
- [Tip Arbiter](https://appshunter.io/ios/app/tip-arbiter/id6761786879)

All apps by Robert Corbin: https://appshunter.io/developer/1890247992

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-11.*