Abstract
The possibility of applying glow discharge in hydrogen for the cleaning of the FTU (Frascati Tokamak Upgrade) vacuum chamber was analyzed on a 1:1 scale toroidal section by using the same operating conditions as foreseen for the machine. The discharge was maintained for six hours in the chamber with the wall temperature kept at 150 degrees C. The partial pressures at the end of the cleaning run were compared with those obtained by using only thermal outgassing at the same temperature. A reduction of about a factor of two in the H/sub 2/0 and C0/sub 2/ partial pressures was observed, related to a better cleanness of the surface. It was found that the high temperature during the glow discharge cleaning not only increases the efficiency of the discharge, but it is an efficient tool to remove impurities from the hidden regions, defined by the thermal shields that cover all the vacuum vessel walls not directly exposed to the glow discharge.
Citation Formats
Ciotti, M, Apicella, M L, Verdini, L, and Ferro, C.
FT Tokamak Upgrade (FTU) vacuum vessel section cleaning by glow discharge in hydrogen.
Italy: N. p.,
1991.
Web.
Ciotti, M, Apicella, M L, Verdini, L, & Ferro, C.
FT Tokamak Upgrade (FTU) vacuum vessel section cleaning by glow discharge in hydrogen.
Italy.
Ciotti, M, Apicella, M L, Verdini, L, and Ferro, C.
1991.
"FT Tokamak Upgrade (FTU) vacuum vessel section cleaning by glow discharge in hydrogen."
Italy.
@misc{etde_10107692,
title = {FT Tokamak Upgrade (FTU) vacuum vessel section cleaning by glow discharge in hydrogen}
author = {Ciotti, M, Apicella, M L, Verdini, L, and Ferro, C}
abstractNote = {The possibility of applying glow discharge in hydrogen for the cleaning of the FTU (Frascati Tokamak Upgrade) vacuum chamber was analyzed on a 1:1 scale toroidal section by using the same operating conditions as foreseen for the machine. The discharge was maintained for six hours in the chamber with the wall temperature kept at 150 degrees C. The partial pressures at the end of the cleaning run were compared with those obtained by using only thermal outgassing at the same temperature. A reduction of about a factor of two in the H/sub 2/0 and C0/sub 2/ partial pressures was observed, related to a better cleanness of the surface. It was found that the high temperature during the glow discharge cleaning not only increases the efficiency of the discharge, but it is an efficient tool to remove impurities from the hidden regions, defined by the thermal shields that cover all the vacuum vessel walls not directly exposed to the glow discharge.}
place = {Italy}
year = {1991}
month = {Sep}
}
title = {FT Tokamak Upgrade (FTU) vacuum vessel section cleaning by glow discharge in hydrogen}
author = {Ciotti, M, Apicella, M L, Verdini, L, and Ferro, C}
abstractNote = {The possibility of applying glow discharge in hydrogen for the cleaning of the FTU (Frascati Tokamak Upgrade) vacuum chamber was analyzed on a 1:1 scale toroidal section by using the same operating conditions as foreseen for the machine. The discharge was maintained for six hours in the chamber with the wall temperature kept at 150 degrees C. The partial pressures at the end of the cleaning run were compared with those obtained by using only thermal outgassing at the same temperature. A reduction of about a factor of two in the H/sub 2/0 and C0/sub 2/ partial pressures was observed, related to a better cleanness of the surface. It was found that the high temperature during the glow discharge cleaning not only increases the efficiency of the discharge, but it is an efficient tool to remove impurities from the hidden regions, defined by the thermal shields that cover all the vacuum vessel walls not directly exposed to the glow discharge.}
place = {Italy}
year = {1991}
month = {Sep}
}