Friday, May 6, 2016

CPVC Adapter Failures

Following series of photographs show CPVC fire sprinkler head adapter.  Thread assembly appears to have separated from plastic molding.

Following photograph shows a CPVC fire sprinkler head adapter and a recalled horizontal sidewall fire sprinkler head (HSW).  Adapter assembly departed CPVC pipe during wrenching by a fire sprinkler service technician.  Fire sprinkler head was installed with anaerobic pipe dope.  Pipe dope solidified making fire sprinkler head removal impossible. Design/install error, not an adapter failure, per se.

The next series of photographs shows a CPVC adapter (reducing coupling) failure.  A longitudinal crack is noted on the adapter.  A working hypothesis is that the adapter failed under high mechanical torque loads applied during fire sprinkler installation.  No test data is available to support or refute this hypothesis.  Assembly was for standard spray upright (SSU) fire sprinkler head installed in a wet pipe system protecting ordinary combustible construction a hotel. Evidence of particulate matter/contamination in the water supply is shown.

The following series of photographs show another reducing coupling CPVC head adapter failure.  Cause of the failure is unknown.  A hypothesis of excessive torque loads applied during fire sprinkler installation would be reasonable; there is, unfortunately, no evidence to support such a hypothesis.  The sprig up was installed with SSU head in an ordinary combustible concealed location, not subject to NFPA 25 inspection.  Occupancy was another hotel.

Another adapter failure or damaged adapter (you will need to "zoom in" to the female threaded inlet of this fitting)

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