GB510963A - Improvements in and relating to the production of pipeless ingots - Google Patents

Abstract

510,963. Castings ; welding by fusion. KELLOGG CO., M. W. Feb. 10, 1938, Nos. 4260 and 4261. Convention dates, Feb. 10, 1937, and Aug. 28, 1937. [Classes 83 (i) and 83 (iv)] Pipes in ingots are filled by electrically depositing weld metal beneath a blanket of flux. An electrode 17 is preferably fed at a predetermined rate by the usual welding head 19 and the voltage maintained while an amperage up to 10,000 per inch diameter of electrode is supplied, this being reduced as the cavity is filled to allow the deposited metal to solidify and avoid the formation of a pipe therein. The ingot, preferably still molten at the pipe, or the electrode may be rotated or oscillated during the process. The electrode should be of such a composition, or have such constituents in its coating or fed separately, that the deposited metal is of the same composition as the ingot. A non-gassing flux should be used ; such as manganese, aluminium, iron, alkaline earth, or other silicate or an aluminate or titanate or the constituents thereof, slag from the manufacture of chrome iron or from a steel finishing furnace. The flux may also include ferro-silicon or other constituent to facilitate the production of the desired deposit. In a modification a number of, preferably two, electrodes are used and these are preferably connected in series to produce an arc struck directly from one to the other or from each to the ingot. If desired metal is supplied separately, in solid or molten form. It a hot top is used in casting an ingot its volume should be only 5 per cent. of the whole ingot and the pipe need only be filled to the crop line. The Specification as open to inspection under Sect. 91 comprises also the use of the process for castings other than ingots, for filling surface cracks, and porous areas in metal bodies. In repairing cracks &c. the metal immediately surrounding the imperfection is removed by chipping, grinding, &c. and the cavity filled as above. Before closing the circuit the end of the electrode may be spaced from the body by an arc starter and be covered with flux. The heat should be sufficient to fuse the walls of the cavity. In another modification a carbon or other substantially non-destructible electrode may be used. This subject-matter does not appear in the Specification as accepted.