Wine Bottle Failure Analysis that Revealed a Manufacturing Defect as the
Cause of Failure
Introduction
A root cause failure analysis was performed
by Read Consulting on a failed wine bottle. The failure initiated in the bottle
neck under the label.
Strategy
Examine the visible fracture surfaces and
determine approximate location of the fracture initiation site.
Expose the fracture surface at the initiation
site and perform a root cause failure analysis
Results
An overview of the bottle as it was received
for the failure analysis is shown in Figure #1. The travel directions of the
exposed cracks indicated that the failure origin was in the bottle neck under
the foil.
Figure #1: Overview of the as received wine bottle.
The foil was removed (Figure #2) and what
appeared to be the failure origin was inside the neck (Figure #3). Therefore,
the neck was cut from the opposite side of where the apparent origin was
seen. The neck was opened up and the failure origin was exposed (Figure #'s 4 &
5).
Figure #2: Photograph of the neck of the failed wine bottle.
This photo was taken after the foil was removed.
Figure #3: Detailed photograph of the neck in the region of the
failure initiation site (star shaped crack cluster right of the red bar).
Figure #4: Photograph of one half of the bottle neck after the
neck had been opened up to allow proper failure analysis. The failure origin is
the milky white region in the photograph.
Figure #5: Close-up of the failure origin. The cracking emanates
from the milky white material in the center of the photograph. It appears as if
the root cause of this failure is a piece of un-melted cullet (recycled glass)
(Mag. 20X).
Root Cause of Failure
This failure analysis revealed that a piece
of un-melted glass had created cracks in the bottle as it cooled down from the
forming operation. The final failure occurred when the cork screw was leveraged
to remove the cork.
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