FU-22S/Z is a direct thermal carbonization thorium tungsten cathodes,metal,glass triode.anode cooling as water-cooled (S) and evaporative cooling(Z),the maximum anode dissipation power is 20kw(S)/30kw(Z),the maximum operating frequency is 26MHz,the output power up to 30KW,the pipes are mainly used in industrial high-frequency heating equipment.