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Title: Fusion bonding of non-pressurized process piping: A new technology and a new approach

Abstract

Perhaps the best-known method of thermoplastic fusion bonding for process piping is hot-plate or heated-tool butt welding. Despite the age of this method and the considerable research available on the subject, in practice, this method of heat fusion relies largely on the skill and knowledge of the machine operator. Hence, the quality of the completed fusion bond is largely dependent on human factors. Another method for joining thermoplastic process piping with heat fusion has been through the use of electrofusion fittings or couplings. A sleeve with an embedded resistance wire is slipped onto mating pipe ends, and welding takes place by electrically heating the resistance wire and forming a molecular bond on the outside surface of the mated pipes. While butt welding tends to rely heavily on the knowledge and experience of the machine operator, electrofusion fittings tend to rely more on automated mechanisms such as the software in the computerized fusion box. An alternative form of thermoplastic welding that employs the features of both butt welding and electrofusion couplings has recently been developed. This unique method employs the principles of electrofusion for performing butt welding. The authors have successfully demonstrated this technology at a major US chemical manufacturer`s facilitymore » to produce reliable, leak-tight fusion joints in non-pressurized, process piping applications. Research and practical experience were blended to provide consistent fusion quality based on monitoring key fusion parameters, while still relying on the experience and training of a fusion operator.« less

Authors:
;  [1]
  1. Evanco Environmental Technologies, Inc., Bracebridge, Ontario (Canada)
Publication Date:
OSTI Identifier:
253820
Report Number(s):
CONF-960156-
ISBN 1-57698-001-4; TRN: IM9630%%271
Resource Type:
Conference
Resource Relation:
Conference: 2. international symposium on the mechanical integrity of process piping, Houston, TX (United States), 30 Jan - 1 Feb 1996; Other Information: PBD: 1996; Related Information: Is Part Of Second international symposium on the mechanical integrity of process piping: Proceedings; Sims, J.R.; Aller, J.E.; Becht, C. IV; Reynolds, J.T.; Salot, W.J.; Sanders, B.J.; Springer, S.P. [eds.]; PB: 420 p.
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING NOT INCLUDED IN OTHER CATEGORIES; 36 MATERIALS SCIENCE; PIPES; BONDING; THERMOPLASTICS; PIPE JOINTS; QUALITY CONTROL; ELECTRIC HEATING; TECHNOLOGY ASSESSMENT; MATHEMATICAL MODELS

Citation Formats

Cooper, R.J., and Pinder, R. Fusion bonding of non-pressurized process piping: A new technology and a new approach. United States: N. p., 1996. Web.
Cooper, R.J., & Pinder, R. Fusion bonding of non-pressurized process piping: A new technology and a new approach. United States.
Cooper, R.J., and Pinder, R. 1996. "Fusion bonding of non-pressurized process piping: A new technology and a new approach". United States. doi:.
@article{osti_253820,
title = {Fusion bonding of non-pressurized process piping: A new technology and a new approach},
author = {Cooper, R.J. and Pinder, R.},
abstractNote = {Perhaps the best-known method of thermoplastic fusion bonding for process piping is hot-plate or heated-tool butt welding. Despite the age of this method and the considerable research available on the subject, in practice, this method of heat fusion relies largely on the skill and knowledge of the machine operator. Hence, the quality of the completed fusion bond is largely dependent on human factors. Another method for joining thermoplastic process piping with heat fusion has been through the use of electrofusion fittings or couplings. A sleeve with an embedded resistance wire is slipped onto mating pipe ends, and welding takes place by electrically heating the resistance wire and forming a molecular bond on the outside surface of the mated pipes. While butt welding tends to rely heavily on the knowledge and experience of the machine operator, electrofusion fittings tend to rely more on automated mechanisms such as the software in the computerized fusion box. An alternative form of thermoplastic welding that employs the features of both butt welding and electrofusion couplings has recently been developed. This unique method employs the principles of electrofusion for performing butt welding. The authors have successfully demonstrated this technology at a major US chemical manufacturer`s facility to produce reliable, leak-tight fusion joints in non-pressurized, process piping applications. Research and practical experience were blended to provide consistent fusion quality based on monitoring key fusion parameters, while still relying on the experience and training of a fusion operator.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = 1996,
month = 7
}

Conference:
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  • A fusion technology development and demonstration concept is conceived using a plasma based volumetric neutron source capable of providing a range of fusion power and wall loading levels during testing, developing, and demonstration stages of operation. The high performance anticipated for the spherical torus (ST) plasma permits large physics margins for the initial neutron wall loading of 0.5 MW/m(2), while still allowing a long-term power reactor relevant physics performance goal of 5 MW/m(2) with reduced margins. An ST-VNS takes advantage of low magnetic field and compact plasma to implement full remote replacement of the center leg of the toroidal fieldmore » coil, the divertor, the first wall, the shield, and the test blanket modules. At the initial stage of operation, only modest neutron wall loading (0.5 MW/m(2)) would be attempted. Success in achieving reliable operations at 2 MW/m(2) in wall loading at a later stage would fulfill the goals of the VNS; success at 5 MW/m(2) would permit component testing for the demonstration power plants. This approach of ST-VNS provides a realistic opportunity for the ultimate demonstration of safe, reliable, and environmentally attractive fusion systems.« less
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