A SMALL TRIODE: 8000 WATT...
May be this page will be not useful to you; I'll give you information about a tube (FTL 3-2 by BROWN BOVERI) capable to give us 8000 W P.E.P; it was in an industrial "furnace" (something like a big micro-wave-furnace!");
you can download data sheet for triode FTL 3-1/FTL 3-2/FTW 3-1 and for diode DQ4/DQ4a/DQ4c (high voltage rectifier).
Download Triode Data Download Diode Data
73 de iz7ath Talino