I've been working with a team of 'designers' that are highly concerned over a potential failure mode of ABS plastic. Their theory is that under a static load well under the yield point of the material that a plastic ABS part will eventually stretch and fail.
The specific example is a handle that I've calculated to hold over 190 lbs before yielding is being loaded to 30 lbs and held there for seven plus days.
The only type of failure I can think of that this could be would be creep, but since we're working at constant room temperature, constant load, evenly distributed load over a wide surface (3 square inches) and so far below the yield point I can't imagine that this test would produce any useful results.
Can anyone think of anything this test would show? Is there a failure mode that I'm not thinking of (specific to ABS or not)? Or is this more likely a test in futility?