Date of Award
Doctor of Philosophy (PhD)
Composite piping systems are becoming the "System of Choice" in many applications previously the domain of metallic piping systems. For full acceptability and usage of these composite piping systems, new innovative approaches must be developed. Three areas of development are addressed; (i) thermal efficiency, (ii) fire endurance, and (iii) joining techniques. In the development of the energy conserving composite pipe, the thermal contact resistance acts as an additional insulating layer. A model and device to predict and measure the contact resistance for a pipe system has been developed. A corrugated layer, which acts as an enhanced contact resistance layer, forms a "dead air" space between composite layers, improving the insulating capability of the system. With the increased usage of composite pipe in nonessential services, the question of performance in essential services, e.g. fire protection systems, must be addressed. The performance of composite pipe in a deluge water delivery system is specifically addressed, where the system is initially dry until a fire is detected. It is in these critical minutes when the system is most vulnerable. Different configurations, which incorporate the usage of a thicker wall and/or an internal fire shield show that specially designed composite pipe is capable of withstanding exposure to a hydrocarbon fire in the dry condition for a predetermined amount of time. In any piping system, joints are a potential source of weakness. A joining method which connects composite to composite and alloy and using glass fabric pre-impregnated with resin has been developed and tested. Results reveal that this approach offers a stronger weld in comparison to the present state-of-the-art joining approach used to connect composite to composite pipe. This same approach has proven to very effective when joining composite to alloy pipe. By developing the aforementioned approaches, the technical barriers which exist may be addressed. Therefore, the performance of composite piping systems may be greatly improved, extending the service of such systems to essential applications.
Stubblefield, Michael Andre, "Performance of Composite Piping Systems: Thermal, Fire Endurance, and Joining Characteristics." (1997). LSU Historical Dissertations and Theses. 6528.