Pipe Failure

    CPVC Plastic Pipe Failure

    By Dr. Duane Priddy Sr. · Published August 6, 2020

    Plastic pipe failure can be catastrophic and leads to millions of dollars of property damage every year. These failures have a number of causes, including:

    • improper selection of materials
    • manufacturing or fabrication defects
    • poor part design

    A Case Study

    PROBLEM: CPVC pipe failure leading to water damage property loss.

    Plastic pipe failure can be catastrophic and leads to millions of dollars of property damage every year. These failures have a number of causes, including:

    • improper selection of materials
    • manufacturing or fabrication defects
    • poor part design
    • improper installation
    • exposure to aggressive chemicals, contaminants, or UV
    • abuse

    QUESTION: Were the caulks and spray applied to CPVC plastic piping compatible?

    CPVC pipe has been used successfully for decades. However, if exposed to certain chemicals, premature failure can occur. Plastic Expert Group was tasked with determining if the applied caulks and sprays were compatible with CPVC, or if the use of these materials led to the failure of the CPVC pipes.

    Three orange CPVC pipes running through foil-faced insulation, with arrows labelling caulk deposits at three joints and overspray on the pipe surface

    ANALYSIS: Determine the identity of the caulks and spray through scientific analysis, then determine the compatibility of each product with CPVC plastic piping.

    All caulks and sprays were removed and analyzed at the molecular level to determine their exact chemical makeup. Our scientists were able to determine each product’s identity with >99% accuracy. It’s as accurate as reading a label.

    FTIR transmittance spectrum of the unknown caulk, captioned Unknown Caulk Molecular Makeup

    A grey double-headed arrow captioned greater than 99% Match

    FTIR transmittance spectrum of the known reference material, captioned Known Material Molecular Makeup

    CONCLUSION: Caulks and spray used were incompatible with CPVC, leading to premature failure.

    Plastic Expert Group concluded that each of the materials in contact with the CPVC pipe was incompatible. These incompatibles were both known and well documented by the caulk manufacturer. Because of the application of these products, premature failure of the CPVC pipe occurred.

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