Getter

Operation

It avoids the appearance of remanent Gaz in the tube. The modern tubes are often equipped with a getter of small size, generally of circular form, which contains a Métal which oxidizes quickly; the Baryum is most current. Once the Vide carried out and it sealed off envelope, the getter is heated at high temperature (often by induction with radio frequencies) what causes the evaporation of the metal contained by the getter . Metal then absorbs residual gases by creating in the majority of the cases a deposit of color silver plated on the envelope of the tube. If an escape develops on the tube, the deposit disappears by reaction with the Oxygène, leaving a white deposit. The specialized tubes and the tubes of strong power often use more exotic getters . Those are of " type; Non-Evaporables" but require nevertheless to be " actives" c.a.d heated has temperatures ranging between 300 and 900°C. They act by chimi-sorbtion, for all chemically active gas, and by adsorbtion for hydrogen. This type of getter is always based on alloys containing Zirconium or of Titanium. The principal manufacturer is an Italian company: Saes Getters.

Diagram

Random links: