The Shift from Torque to Clamping Force
In 1997, the primary focus was on ensuring that wheels had the correct torque applied to the studs, securing them to the hub. Despite torque being measurable and defined as tension on the studs, a significant issue persisted – many wheels were still coming loose, resulting in damage or, worse, wheel-offs. The Tire Industry Association (TIA) later discovered and heavily implemented a shift in focus towards achieving proper clamping force, a measurement of the force applied between the mating surfaces of the wheel and hub face.
Challenges in Clamping Force Measurement
One major challenge is the absence of convenient tools to measure the clamping force on a wheel assembly. Additionally, the correlation between torque and clamping force is not straightforward. It is erroneous to assume that the torque applied is achieving the required clamping force. Instead, a thorough inspection of factors influencing clamping force, such as debris, rust, or dirt caught between mating surfaces during the mounting process, is crucial to prevent potential wheel-offs.
TIA’s Solution – The RIST Procedure
To address these challenges, the TIA introduced the RIST procedure:
- R – Remove debris from mating surfaces
- I – Inspect components for excessive wear.
- S – Snug fasteners in a star pattern
- T – Torque to specification.
Ensuring Adequate Clamping Force with RIST
Implementing the RIST procedure provides fleets with a method to significantly reduce the risk of wheel-offs. By ensuring that clamping force is met through meticulous steps like removing debris, inspecting components, and following a specific torque sequence, the procedure enhances wheel safety.
Counteract’s RIST Procedure Kit
Part # STK-WMK – One of Counteract’s Commercial Wheel Maintenance Kits
Counteract has developed a RIST procedure kit designed to clean all major mating surfaces efficiently. This includes the hub and wheel face, studs, nuts, stud holes, and even the valve stem hole on the wheel. With a focus on quality and speed, these kits facilitate the swift execution of the RIST procedure, ensuring optimal safety measures are applied to prevent wheel-related incidents.
Check out Counteract’s Kits at the link below!
https://counteractbalancing.com/products/kits/
