In this episode, we sit down with Atlas Copco’s tightening expert, known in the industry as the Guru of Tightening, to explore the surprisingly complex and crucial world of bolted joints. The conversation spans everything from fundamental engineering principles to cutting-edge testing and diagnostic tools used in high-precision manufacturing.
We begin with the staggering strength of bolts. A single M8 bolt, though small, can lift a car. In diesel engines, cylinder head bolts collectively deliver over a million pounds of clamp force. These forces aren’t just theoretical—they’re critical to the performance and safety of everything from vehicles to heavy machinery.
Listeners are taken on a virtual tour of Atlas Copco’s laboratory, where robotic arms and specialized multi-spindle torque tools simulate real-world fastening scenarios. The episode explains how testing M18 bolts in engine blocks or evaluating bolt performance on gear assemblies helps customers optimize joint quality before full-scale implementation.
One of the episode’s key themes is friction—specifically, how it undermines traditional torque-based tightening methods. Demonstrations reveal that a tiny drop of hand sanitizer can increase clamping force sixfold due to reduced friction. Since 90 percent of applied torque is consumed by friction, even minor contaminants can cause bolt failures.
This leads into a deeper explanation of torque-angle strategies. Unlike torque-only methods that are susceptible to friction variability, torque-plus-angle tightening allows for greater consistency and accuracy. These methods support lightweight, cost-efficient designs while maintaining structural reliability.
The episode also highlights the importance of data. Atlas Copco tools now feature ultrasonic systems that measure bolt stretch with nanosecond precision, providing real-time insight into tension, torque, and angle. This enables engineers to tailor their tightening strategy based on the exact mechanical and material demands of each application.
Finally, we look at the evolution of Atlas Copco’s tooling—from air-driven systems to the latest wireless, battery-powered torque tools with embedded sensors and software analytics. These technologies are helping manufacturers ensure quality while improving ergonomics and workflow efficiency.
