The Fatigue Fuse is a small device that can be attached to a metallic structure to measure its remaining life. It is a thin piece of metal consisting of a series of parallel metal strips connected to a common base, much as fingers are attached to a hand. Each of the fingers has a different geometric pattern. In predetermining the geometric contour of each finger, the fatigue life of each of the fingers are finite and predictable. When the fatigue life for a given finger (or fuse) is reached, the fuse breaks.
By using different geometry for each finger, different increments of fatigue life are measurable. Typically, these fingers are constructed to fail at increments of 20% of the metal’s fatigue life. By mechanically attaching or bonding these devices, the Fuse undergoes the same strain sequence as the structure. As the fuses break, they indicate the increment of fatigue life reached for that area of the structure. This allows our clients to accurately plan ahead and know when a structure is failing.
The FF is of value in monitoring aircraft, ships, bridges, conveyor systems, mining equipment, cranes, windmills, turbine engines, etc. Fatigue Fuses have been applied to movable aluminium bridges for the US Army, made by a division of General Dynamics, Inc. No special training is needed to qualify individuals to report any broken segments of the FF to the appropriate engineering authority for any necessary action.