Abstract: The device comprises an immersion probe (10) which is permeable to hydrogen and is made of melt-resistant sintered or calcined ceramic material connected, in a vacuum tight manner via a capillary tube (4), to a pressure gauge (2). The immersion probe (10) features at least two essentially plate-shaped diffusion membranes (7,8) that in each case form a common interface (9). The capillary tube (4) as such communicates freely with the interface (9). The immersion probe (10) is preferably situated in a crucible featuring openings above the level of the probe (10); on dipping the crucible into the melt 12, the openings allow the melt (12) to flow in, permit equalization of the hydrogen content of the metal and, after removing the crucible from the melt (12), allow the melt to flow out leaving a residual amount that protects the probe (10). The measuring probe is robust, easily changed and features a short response time.

Abstract: A process for feeding metal to molten metal, in particular for the purpose of melting solid metal such as scrap metal or dross granules, is such that at least part of the melt is divided and each divided part set into motion rotating in opposite directions so that at least two rotating streams or "rolls" of molten metal are produced. The central axes of these rotating streams of molten metal form an angle. The metal to be melted is charged at the place where the two "rolls" of molten metal meet. The "rolls" of molten metal are produced by introducing the molten metal into a pair of pipe lengths approximately perpendicular to their central axes and approximately tangential to the cross section of the said pipe lengths, the central axes forming an angle, or by causing the molten metal in the pipe lengths to rotate by means of electrodynamic forces.

Abstract: A process for feeding metal to molten metal, in particular for the purpose of melting solid metal such as scrap metal or dross granules, is such that at least part of the melt is divided and each divided part set into motion rotating in opposite directions so that at least two rotating streams or "rolls" of molten metal are produced. The central axes of these rotating streams of molten metal form an angle. The metal to be melted is charged at the place where the two "rolls" of molten metal meet. The "rolls" of molten metal are produced by introducing the molten metal into a pair of pipe lengths approximately perpendicular to their central axes and approximately tangential to the cross section of the said pipe lengths, the central axes forming an angle, or by causing the molten metal in the pipe lengths to rotate by means of electrodynamic forces.

Abstract: The temperature measuring device comprises a rod which passes approximately vertically through the anode block and terminates at the level of the working face of the anode. Fitted over the rod at the top is a light plug which provides an optical connection to the fiber bundles with the minimum of reflection. This optical connection is usefully in a coupling fluid which, like the rod and the bundle of fibers, is able to transmit infra-red radiation.

Abstract: A tool for underwater welding comprises an open-mouthed bell with an axially extending electrode inside, part of that electrode being surrounded by a tube supplying gas under pressure from a pumping station floating on the surface. Another tube linking the bell with that pumping station supplies water under pressure to an annular chamber open toward an array of fluid-guiding blades carried by the bell. In one embodiment, the bell is rotatably mounted and carries the blades on its outer surface, being set in rotation by the oncoming flow; in another embodiment, the bell is stationary and the blades are arranged on its inner surface whereby the water swirls in a film along that surface. In either case the circulating water forms a vortex that passes along the bell periphery and around the bell mouth which is slightly spaced from the workpiece to be welded, the resulting centrifugal forces preventing the entry of surrounding water into the bell whereby a gaseous atmosphere is maintained in its interior.

Abstract: A self-implanting anchor comprising an elongated body having a first portion comprised of a consumable combustible material extending from a leading end of the body and back along the length of the body, and a second portion defining an anchor for implantation in a compact material and which extends from the first portion of the body and back along the length thereof. The elongated body includes a conduit extending axially therethrough and opening at the leading end of the body for supplying an oxidizer through the conduit to the consumable combustible material at the leading end. In use, the leading end portion is positioned against a surface of the compact material and the combustible material is ignited to melt the compact material in a vicinity of the leading end portion of the elongated body.