722,494. Supply systems for welding arcs. AIR REDUCTION CO., Inc. Dec. 8, 1952 [Dec. 28, 1951], No. 31074/52. Drawings to Specification. Class 38 (4). To permit the employment of a relatively low high-frequency (say 50 to 500 kcs. per sec.) current for starting and stabilizing a D.C. or low-frequency A.C. welding arc, the highfrequency inductor or transformer disposed in the welding circuit and necessary for the injection of the high-frequency current has a core of ferrite material or powdered iron and is arranged to saturate at normal welding currents so as to offer little impedance to the flow of welding current, but to be unsaturated by the high-frequency currents alone, so as to offer high impedance to these-and thus provide good injection of high-frequency currentwhen the arc extinguishes. The high-frequency generator may comprise a push-pull valve oscillator normally cut off by external bias, but triggered into oscillation by a voltage pulse induced in a winding of the injection transformer upon interruption of the flow of welding current.

Electric arc welding

Fluxes of the following compositions in parts by weight: (a) 45 rutile, 5 fluorspar, 15 felspar, 16 high carbon ferro-manganese, 185 other alloying materials, eg, ferro-molybdenum and ferro-chromium or (b) 30 rutile, 10 fluorspar, 8 limestone, 5 felspar, 22 ferro-chromium, 6 nickel, 10 ferro-niobium are used as electrode coatings in arc welding (see Group XXII) Specifications 584,299, 795,672 and 860,959 are referred to

Method and apparatus for arc working with gas shields having coherentstreaming

This invention relates to electric arc welding, and finds particular application when direct current is used in the process known as stud welding In this process a stud is held in a gun with its end near to a metal surface to which the stud is to be welded, and an arc is struck between the

A narrow groove welding torch having an internally insulated metallic housing and a rectangular cross section with cooling ducts and shielding gas ducts disposed within the housing.

Mikhalapov George

Papers

Method and apparatus for welding with gas shields having laminar flow