📋 Case Study

Fatigue-Cracked Articulation Joint on Autonomous Grain Cart

Geometry prevents full-penetration weld; high-cycle fatigue loading (>10⁷ cycles); AI-guided inspection flagged anomaly

🏗️ Project Overview

Micro-crack network in pivot joint of autonomous grain cart operating 22 hrs/day

🎯 Challenge

Geometry prevents full-penetration weld; high-cycle fatigue loading (>10⁷ cycles); AI-guided inspection flagged anomaly

🔧 Design Approach

U-groove partial penetration weld with GTAW root pass + FCAW fill; PQR qualified with accelerated fatigue testing (R=0.1, 10 Hz) per ASTM E466

📐 Design Diagram

AI-generated project design illustration

📐 Key Calculations

Fatigue Life Multiplier

(Δσ_ref / Δσ_test)^m

Result: 1.8×

Quantifies life extension vs. as-welded condition

Stress Concentration Factor (Kt)

σ_max / σ_nominal

Result: 2.3

Driven by groove geometry — minimized via optimized radius

📊 Results

Tested to 12.7M cycles without failure; integrated into OEM’s predictive maintenance algorithm; extended service interval from 1,000 to 3,200 hrs

💡 Lessons Learned

• •Accelerated fatigue testing is essential for autonomous equipment repairs
• •Kt reduction yields greater life gain than filler upgrades alone

✅ Key Takeaways

• 1Accelerated fatigue testing is essential for autonomous equipment repairs
• 2Kt reduction yields greater life gain than filler upgrades alone