Epoxy Modifications—A Novel Sealing Material for Rehabilitation of Pipe Joints
The main reason for the flexibilisation of this epoxy sealing material is the necessity of the materials ability to compensate relative movements between the pipe segments. Epoxy (EP) modified with ethylene–propylene–diene rubber (EPDM) powder, reactive liquid polymer (ATBN—amine-terminated butadiene–acrylonitrile), and epoxidised modifiers as well as two customised epoxies were analysed. Concerning the dynamic-mechanical analysis, the formulations with reactive liquid polymer (ATBN) or EPDM showed nearly constant mechanical properties in the application temperature range (7–17 ℃). The formulations with epoxidised modifier and the customised proprietary epoxy showed a slope in this temperature range. Generally the glass transition temperature decreased and thus a change of the materials operating temperature range occurred. Thermogravimetric analysis showed that all epoxy modifications absorb water after immersion. Due to the water absorption a plasticisation effect was observed. Further changes in the materials operating temperature ranges have to be considered. A comparison with neat epoxy shows for all formulations a reduction of the mechanical properties like tensile strength and modulus of elasticity. However, no enhancement of strain at break could be achieved by modifying with EPDM powder. The modified epoxy EP/ATBN 2 as well as the customised epoxy C-EP 1 fulfilled the requirement of pressure resistance up to 1 MPa. The measured major strain was negligible. Results of the pressure and inclination test at the fibre concrete test rig show, that the tightness as well as the flexibility (inclination) of the repaired socket can be guaranteed up to a pressure of 1.3 MPa. Finally, a pressure test in a first field application confirmed the suitability of the epoxy based material C-EP 1 for use as a robot processed sealing material.
This work is part-financed by the Project DeWaLoP from the European Regional Development Fund, Cross-Border Cooperation Program Slovakia-Austria 2007–2013 “Creating the Future” and Vienna Water.
- 1.Werderitsch, M.: Personal communication, 25th Aug. 2010Google Scholar
- 2.Kottmann, A.: Rohre und Rohrwerkstoffe in der Gas- und Wasserversorgung. Vulkan-Verlag, Essen (1997)Google Scholar
- 3.Burn, S., DeSilva, D., Eiswirth, M., Hunaidi, O., Speers, A., Thornton, J.: Pipe leakage—Future challenges and sulutions. In: Pipes Wagga Wagga (Wagga Wagga, 12.–14.10.1999). Wagga Wagga (1999), p. 18Google Scholar
- 5.Hunaidi, O., Chu, W., Wang, A., Guan, W.: Detecting leaks in plastic pipes. J. Am. Water Works Assoc. 92, 82–94 (2000)Google Scholar
- 6.Werderitsch, M.: Personal communication, 17th Oct. 2012Google Scholar
- 7.Schoberleitner, C., Archodoulaki, V.-M., Koch, T., Lüftl, S., Mateos, L.A., Vincze, M., Werderitsch, M., Kuschnig, G.: Development of a sealing material and robot for automatic socket rehabilitation of grey cast iron pipes in drinking water supply systems. Water Sci. Technol. Water Supply 13, 924–931 (2013)CrossRefGoogle Scholar