Investigation of extrusion failures of PTFE-based gaskets in chemical plant service
- Eastman Chemical Co., Kingsport, TN (United States)
- Monsanto Co.--The Chemical Group, Pensacola, FL (United States)
PTFE-based gaskets in chemical plant service typically fail in an extrusion mode, sometimes referred to as blowout. Test work previously published by Monsanto indicated that correctly installed PTFE-based gaskets have pressure performance far exceeding system pressure ratings. These results have since been confirmed by extensive testing at the Montreal based Ecole Polytechnique Tightness Testing and Research Laboratory (TTRL), funded by a consortium of gasket users and manufacturers. With the knowledge that properly installed gaskets can withstand system pressures in excess of 1,000 psig [6,894 kPa], failures at two chemical plants were re-examined. This analysis indicates that extrusion type failures can be caused by excessive internal pressures, associated with sections of pipe having an external source of heat coincident with a blocked flow condition. This results in high system pressures which explain the extrusion type failures observed. The paper discusses details of individual failures and examines methods to prevent them. Other causes for extrusion failures are reviewed, with a recommendation that stronger gasket materials not be utilized to correct problems until it is verified that excessive pressure build-up is not the problem. Also summarized are the requirements for proper installation to achieve the potential blowout resistance found in these gaskets.
- OSTI ID:
- 404145
- Report Number(s):
- CONF-960706-; ISBN 0-7918-1773-3; TRN: IM9652%%5
- Resource Relation:
- Conference: American Society of Mechanical Engineers (ASME) pressure vessels and piping conference, Montreal (Canada), 21-26 Jul 1996; Other Information: PBD: 1996; Related Information: Is Part Of Computer technology -- 1996: Applications and methodology. PVP-Volume 326; Hulbert, G.M. [ed.] [Univ. of Michigan, Ann Arbor, MI (United States)]; Hsu, K.H. [ed.] [Babcock and Wilcox, Barberton, OH (United States)]; Lee, T.W. [ed.] [FMC Corp., Santa Clara, CA (United States)]; Nicholas, T. [ed.] [USAF Wright Laboratory, Wright-Patterson AFB, OH (United States)]; PB: 217 p.
- Country of Publication:
- United States
- Language:
- English
Similar Records
HIGH-TEMPERATURE FLANGED JOINTS INCORPORATING PTFE SEALING GASKETS
Collective Summary of sCO2 Materials Development (Supercritical Transformational Electric Power Generation (STEP) Level 2 Milestone Report) (Parts I - II)