"If this method to restore emission is to work, how do you keep the filament from burning up and the acetylene gas from igniting while in a non-vacuum filament on time? What`s the rest of the story Mr. Measures? Jim."
Actually I have heard of this. They first pull another vacuum before they introduce the acetylene gas. Without oxygen, the acetylene gas can not ignite nor can the filament burn out. After it is allowed to cook, the acetylene is purged, another vacuum is pulled and the evacuation tube is heated, pinched off and closed. They generally place the evac tube on the bottom of the glass envelop between the pins. After it is closed, they re-heat the tit and use a tool to flatten it. It takes a good glass blower to do this. On the production line, as was stated, they are all automated and everything is aligned with jigs. The envelope is the closed in two pieces in a lathe, a vacuum drawn, and the evac tube sealed off. The tube itself is allowed to burn in. On the smaller tubes, a "getter" is flashed to absorb any left oxygen or other gasses before the burn in. If I'm not mistaken, the getter is made in the form of a magnesium alloy. On rebuilds, if the grids plating is not harmed, they re-use the old. In the case of damaged components, it has to be rebuilt from scratch. This info, I got from a tech at GE years ago down in Owensboro, KY.
Will Matney
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
|