The following language is identical to Recommendation C of the Plastics Pipe Institute.
Pressure Rating of PVC Plastic Piping for Water at Elevated Temperatures
The factors given in the attached table are suggested for use in determining the pressure ratings for water for PVC plastic piping at temperatures above the standard temperature, 73.4 F (23 C). These factors are based on the assumption that the piping system should be capable of operating continuously at the rated pressure while the medium in the system, the piping materials and the atmosphere around the piping are at the same design temperature. It is well known that these conditions seldom exist which makes the suggested factors conservative. Any economies in design pressures are better accomplished by more precise determination of operating pressures and temperatures rather than by using less conservative factors.
These factors are only suggestions to be used when actual test data are not available. Further consideration should be given to the type and quality of the joints in the system. Actual test results on the specific PVC pipe compound fittings and joints are more accurate and consequently more reliable. Therefore, it is not the intent that these suggested factors supplant actual test results.
These factors were developed after careful analysis of all the test data, manufacturers' recommendations, and experience available. Any long-term hydrostatic test data or experience that anyone has to either support or indicate that these suggested factors need to be changed and that they would be free to submit will be welcomed.
It is recommended that all PVC pressure pipe to which these service factors are applied meet fully the requirements of current ASTM, Product Standards, Canadian Standards and or standards of similar high quality.
Pressure Rating Factors of PVC Pipe
for Water at Elevated Temperatures
|Temperature||Pressure Ratings Factor (b)|
- Conversions from Fahrenheit to Celcius scale are rounded-off to the nearest whole degree.
- To be applied to the water pressure ratings for specific types and sizes of PVC pipe as given in current Product Standards and in the Appendicies of ASTM specifications.
NOTE: This PPFA User Bulletin is designed to provide guidance in achieving the efficient, effective and proper use of plastic pipe. The suggestions and advice contained in the Bulletin are offered merely to provide plastic pipe users with a general frame of reference. Because specific situations may and often do require special treatment, the suggestions and advice are obviously not universally applicable. Therefore, the user should carefully assess the requirements of his specific situation before making practical application of anything contained in this publication.