Pumping-Out of ElectroVacuum Devices with Parts Separation

The object of the research is the technological process of VED pumping-out with parts - separation.

The aim of the work is to optimize a technological process which provides the lowest pressure in the VED and helps in reducing negative self-influencing of electrodes at degassing.

For achieving the goal the following theoretical and experimental research has been conducted:

the model of the pumping-out technological process has been developed. It allows taking into consideration parts - clearance, gas disposal from inter-electrode space and vacuum parameters of the equipment;

the influence of parts - separation size on the effective pumping-out speed and vacuum conditions of the device degassing has been investigated;

gas flows emitted from electrodes at pumping-out have been searched for finding out optimal conditions of cathode vacuum-thermal treatment.

The theoretical and experimental dependences received allow optimizing VED pumping-out, i.e. maximum eliminate electrodes negative self-influencing.

-VED pumping-out cycle with parts - separation for 20-25 mm reduces 1,6-1.7 fold in comparison with the VED pumping-out cycle with parts - separation for 0,5-5,0 mm;

At pumping-out there is an optimal parts - separation, providing the lowest gas pressure in the device. At the following parts - separation vacuum and electrical parameters of the device do not change;

At pumping-out electrodes separation in an optimal distance provides improving vacuum-thermal conditions of the cathode treatment at the expense of reducing pressure in the inter-electrode space 1-1,5 fold. Devices working at current density up to 0,25 A/cm2 may be treated in the inter-electrode distance 5-10 mm, and at the current densities up to 1 A/cm2 a cathode and anode should be separated for 15-20 mm. The following electrodes separation does not improve the device parameters.