The Boeing Company
COMPRESSION FITTING WITH VISUAL TORQUE INDICATOR

Abstract:

A tubing nut fastener having elements that are partially rotatable with respect to each other. In between the rotatable elements, engagement members (e.g., balls) are captured within interior channels. The partially rotatable elements include permanent markings or other non-removable visual indicators, which varies spatially depending on whether the tubing nut fastener is in a torqued state or an un-torqued state, thereby providing a visual indication of the status of the tubing nut fastener.