Method of welding a lamp feedthrough assembly; and apparatus the

Details Method of welding a lamp feedthrough assembly; and apparatus the Method of welding a lamp feedthrough assembly; and apparatus the

1984-04-27

1986-04-22

Albritton, Clarence L.

Electric heating

Metal heating

For bonding with pressure

2191171, 219 7801, 445 26, 445 29, B23K 1132

Patent

active

045844542

ABSTRACT:
This invention provides a method of electric current welding in a flowing inert gas atmosphere of an electric feedthrough assembly for an electric lamp, and an apparatus for performing such welds. The method and apparatus are well suited to welding refractory metals, e.g., a molybdenum-titanium-nickel alloy feedthrough body a tungsten electrode for use in an alumina arc tube of a high-pressure sodium lamp, and a molybdenum lead-in wire pin. When the tungsten electrode is inserted into a receiving cavity in the feedthrough body and appropriate pressure applied, the electrical resistance of the solid-to-solid rough interface is greater than that of either the electrode pin or feedthrough so that application of an appropriate electrical pulse causes melting to occur only in the immediate vicinity of the interface whereby extensive recrystallization of the feedthrough body does not occur. A welding electrode in the form of a plate having a thickness approximately equal to the insertion depth of the lamp electrode into the feedthrough body has a cylindrical hole into which the feedthrough body is mounted so that the electrical current applied during the welding process flows primarily radially through the feedthrough body whereby the feedthrough body is further protected against extensive heating during the welding process. Provision of welding electrodes of substantial mass and high thermal conductivity draws heat from the feedthrough during and after the weld so that the feedthrough body is further protected from extensive heating.

REFERENCES:
patent: 2265561 (1941-12-01), Hoern
patent: 3992602 (1976-11-01), Ashton
patent: 4334628 (1982-06-01), Buhrer et al.

Affiliated with

Also associated with

Rating

Method of welding a lamp feedthrough assembly; and apparatus the does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Method of welding a lamp feedthrough assembly; and apparatus the, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method of welding a lamp feedthrough assembly; and apparatus the will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1916878