skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: National Spherical Torus Experiment (NSTX) Torus Design, Fabrication and Assembly

Abstract

The National Spherical Torus Experiment (NSTX) is a low aspect ratio spherical torus (ST) located at Princeton Plasma Physics Laboratory (PPPL). Fabrication, assembly, and initial power tests were completed in February of 1999. The majority of the design and construction efforts were constructed on the Torus system components. The Torus system includes the centerstack assembly, external Poloidal and Toroidal coil systems, vacuum vessel, torus support structure and plasma facing components (PFC's). NSTX's low aspect ratio required that the centerstack be made with the smallest radius possible. This, and the need to bake NSTXs carbon-carbon composite plasma facing components at 350 degrees C, was major drivers in the design of NSTX. The Centerstack Assembly consists of the inner legs of the Toroidal Field (TF) windings, the Ohmic Heating (OH) solenoid and its associated tension cylinder, three inner Poloidal Field (PF) coils, thermal insulation, diagnostics and an Inconel casing which forms the inner wall of the vacuum vessel boundary. It took approximately nine months to complete the assembly of the Centerstack. The tight radial clearances and the extreme length of the major components added complexity to the assembly of the Centerstack components. The vacuum vessel was constructed of 304-stainless steel and requiredmore » approximately seven months to complete and deliver to the Test Cell. Several of the issues associated with the construction of the vacuum vessel were control of dimensional stability following welding and controlling the permeability of the welds. A great deal of time and effort was devoted to defining the correct weld process and material selection to meet our design requirements. The PFCs will be baked out at 350 degrees C while the vessel is maintained at 150 degrees C. This required care in designing the supports so they can accommodate the high electromagnetic loads resulting from plasma disruptions and the resulting relative thermal expansions between the PFC's and the vacuum vessel on which supports are attached. This paper will provide a brief review of the issues associated with the design, fabrication and assembly of the NSTX Torus system including those outlined above.« less

Authors:
; ; ; ;
Publication Date:
Research Org.:
Princeton Plasma Physics Lab., NJ (US)
Sponsoring Org.:
USDOE Office of Energy Research (ER) (US)
OSTI Identifier:
14935
Report Number(s):
PPPL-3396
TRN: US0106857
DOE Contract Number:  
AC02-76CH03073
Resource Type:
Technical Report
Resource Relation:
Other Information: PBD: 1 Nov 1999
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; NSTX DEVICE; ASPECT RATIO; CONSTRUCTION; DESIGN; FABRICATION; TORI; PLASMA DISRUPTION; SOLENOIDS; THERMAL EXPANSION; THERMAL INSULATION; WELDING

Citation Formats

C. Neumeyer, G. Barnes, J.H. Chrzanowski, P. Heitzenroeder, and et al. National Spherical Torus Experiment (NSTX) Torus Design, Fabrication and Assembly. United States: N. p., 1999. Web. doi:10.2172/14935.
C. Neumeyer, G. Barnes, J.H. Chrzanowski, P. Heitzenroeder, & et al. National Spherical Torus Experiment (NSTX) Torus Design, Fabrication and Assembly. United States. doi:10.2172/14935.
C. Neumeyer, G. Barnes, J.H. Chrzanowski, P. Heitzenroeder, and et al. Mon . "National Spherical Torus Experiment (NSTX) Torus Design, Fabrication and Assembly". United States. doi:10.2172/14935. https://www.osti.gov/servlets/purl/14935.
@article{osti_14935,
title = {National Spherical Torus Experiment (NSTX) Torus Design, Fabrication and Assembly},
author = {C. Neumeyer and G. Barnes and J.H. Chrzanowski and P. Heitzenroeder and et al},
abstractNote = {The National Spherical Torus Experiment (NSTX) is a low aspect ratio spherical torus (ST) located at Princeton Plasma Physics Laboratory (PPPL). Fabrication, assembly, and initial power tests were completed in February of 1999. The majority of the design and construction efforts were constructed on the Torus system components. The Torus system includes the centerstack assembly, external Poloidal and Toroidal coil systems, vacuum vessel, torus support structure and plasma facing components (PFC's). NSTX's low aspect ratio required that the centerstack be made with the smallest radius possible. This, and the need to bake NSTXs carbon-carbon composite plasma facing components at 350 degrees C, was major drivers in the design of NSTX. The Centerstack Assembly consists of the inner legs of the Toroidal Field (TF) windings, the Ohmic Heating (OH) solenoid and its associated tension cylinder, three inner Poloidal Field (PF) coils, thermal insulation, diagnostics and an Inconel casing which forms the inner wall of the vacuum vessel boundary. It took approximately nine months to complete the assembly of the Centerstack. The tight radial clearances and the extreme length of the major components added complexity to the assembly of the Centerstack components. The vacuum vessel was constructed of 304-stainless steel and required approximately seven months to complete and deliver to the Test Cell. Several of the issues associated with the construction of the vacuum vessel were control of dimensional stability following welding and controlling the permeability of the welds. A great deal of time and effort was devoted to defining the correct weld process and material selection to meet our design requirements. The PFCs will be baked out at 350 degrees C while the vessel is maintained at 150 degrees C. This required care in designing the supports so they can accommodate the high electromagnetic loads resulting from plasma disruptions and the resulting relative thermal expansions between the PFC's and the vacuum vessel on which supports are attached. This paper will provide a brief review of the issues associated with the design, fabrication and assembly of the NSTX Torus system including those outlined above.},
doi = {10.2172/14935},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Nov 01 00:00:00 EST 1999},
month = {Mon Nov 01 00:00:00 EST 1999}
}

Technical Report:

Save / Share: