What does coupling runout measure?

Coupling runout measures the amount the coupling is out of true, which is essential for ensuring proper alignment between shafts and preventing excessive wear or damage during operation. When a coupling is not perfectly aligned, it can lead to uneven gaps and misalignment that affect the performance of machinery. This measurement is taken by rotating the coupling and observing any deviation from a true circular path, indicating how much it wobbles or is misaligned. Proper measurement and adjustment of coupling runout are crucial to maintain mechanical efficiency and reduce the risk of failure in rotating machinery.

The other options do not accurately describe what coupling runout measures. For example, while vibration levels can be influenced by coupling conditions, runout specifically focuses on geometric alignment rather than vibration amplitude. Outer alignment of the shaft is related but encompasses more than just the true nature of the coupling itself. Torque during installation is an important consideration for ensuring secure connection but does not pertain to runout measurements. Understanding coupling runout helps identify issues that could result in machinery problems, thereby contributing to better overall maintenance practices.