Abstract: In a shaft furnace having a metal shell, a refractory lining of relatively high thermal conductivity and cooling bodies which project inwardly through the shell into the lining and through which in operation cooling liquid flows, has a high uniformity of temperature in the lining. In order to improve its operational characteristics, in particular to improve temperature uniformity yet further while reducing heat loss, the shell and the cooling bodies are screened from the lining. Between the cooling bodies and the refractory lining and between the shell and the refractory lining there are respectively first and second thin layers of refractory material having in each case a .lambda.-value of less than 5 kcal/mh .degree.C., preferably less than 1.5 kcal/mh .degree.C. The thin layers may be of refractory felt or refractory plates.

Abstract: A method of injection of wire into molten steel wherein a coil of the wire is positioned around a mandrel, and the wire is pulled from the coil in the axial direction of the mandrel and is fed by transport means into the molten steel. To avoid the need to rotate the coil and yet to achieve smooth uncoiling and also to permit tow coils to be uncoiled successively without interruption the coil is a self-supporting parallel-wound coil, which is resiliently clamped around at least part of its outer surface over its whole axial length. The axial length of the mandrel is greater than that of the coil and, at the start of uncoiling of the coil there is a gap of at least 5 cm between the inside surface of the coil and the mandrel. The wire is pulled from the inside of the coil from the inside of the coil through a ring which is mounted around the mandrel axially spaced from the coil and which has a slot-shaped radial extension open to the interior of the ring.

Abstract: Pulverized coal feed tanks are emptied in sequence via a transport line into the hot blast of a blast furnace. Each tank is carried by three load cells whose outputs are summed and differentiated to obtain the actual feed rate. Gas pressure in the tank is controlled in dependence on the actual feed rate so as to achieve a desired feed rate. To reduce the possibility of inaccurate feeding of coal, the outputs of the respective load cells are compared, and if deviation from a predetermined weight distribution over the load cells is detected, feed from the tank is stopped. The load cells may be duplicated in series, and the summed outputs of the two sets of load cells compared to detect malfunctioning of a load cell, again resulting in cessation of feeding from that tank.

Abstract: Method and apparatus for producing liquid iron from iron oxide, wherein the iron oxide is substantially converted to sponge iron by passing reducing gas through it in a reduction column and is then melted in a melt vessel which is in open communication with the reduction column by heat generated by reaction of oxygen-containing gas and carbonaceous material which reaction provides said reducing gas. To improve control of the process, the oxygen-containing gas and the carbonaceous material are respectively substantially pure oxygen and coal powder which are delivered separately into the melt vessel, and the liquid iron bath in the melt vessel is stirred so as at least partly to be kept in motion. By separate control of the oxygen and coal supplies, e.g. the level and/or direction of delivery, and by control of stirring, it is possible to control the ratio of CO and CO.sub.2 in the reducing gas and also the heat output in the melt vessel.

Abstract: Ceramic sealing rope, with a core of a strand (1) of yarns (2), each yarn (2) around a solid metal wire (3) and around the core one or more sleeves (4, 5, 7), each sleeve woven crosswire of multiple yarns, each yarn around a solid metal wire.

Abstract: A metallurgical vessel having a bottom, a side wall structure defining an opening remote from the bottom, a refractory lining for the interior of the vessel and a unitary metal flange fixed to the vessel and extending around the opening and over the lining, and having an inner periphery directed towards the opening and an outer periphery wherein in order to reduce thermal stresses in the flange there are a plurality of holes in the flange metal spaced from the inner periphery and extending over the refractory lining and distributed circumferentially around the flange whereby heat flow through the flange from its inner periphery to its outer periphery is restricted.

Abstract: In a shaft furnace having a metal shell, a refractory furnace lining inside the shell and a taphole construction comprising a drilled taphole extending through a plug located in an aperture in the shell and a taphole brick structure forming part of said furnace lining, the taphole brick structure at least partly consists of at least one taphole brick of high thermal conductivity material selected from the group comprising graphite, semi-graphite and material of equivalent heat conductivity, there further being screening means comprising material of substantially lower heat conductivity coefficient than graphite and semi-graphite located between said taphole brick and said furnace shell.

Abstract: In a so-called radial cell for unilateral electroplating of a moving metal strip, the strip as the cathode is in contact with an electrically conductive peripheral surface of a rotating cathode roller. An anode concentric with the roller over a part of the roller circumference is located at a distance from the strip so as to form a slot into which electrolyte is supplied. It has been found that the electrolytic process is improved in uniformity and speed if the electrolyte is supplied only at the entrance end of the slot in the direction of strip movement so that the electrolyte flows turbulently and generally unidirectionally through the slot to the exit end thereof and at a rate such that the average velocity of the electrolyte through the slot is at least 75% of the linear strip velocity. The angular length of the slot can be less than 180.degree.. Preferably the average velocity of the electrolyte through the slot is at least equal to the linear strip velocity.

Abstract: A vertical spigot joint for sealing the space between the socket and the end of a pipe inserted in the socket has an aluminium cord sealing the space and a filler mixture. The filler mixture comprises aluminium cement, vermiculite grains and a plastics material which retains its plastic properties in use. A sleeve of a glass fibre cloth coated with protective layers covers the joint and is secured to the pipe end and socket by silicone putty and by clamping strips. A thermally insulating refractory ceramic felt is provided between the pipe end and the filler material. The use of this filler mixture, together with the provision of the sleeve enables a joint to be produced which is gas-tight and absorbs relative movement of the pipe end and socket due to the media in the pipe or due to thermal expansion and contraction.

Abstract: A gas-transmitting wall element for a metallurgical vessel having a refractory lining is described which is subject to low wear, is reproducible and makes unnecessary continuous blowing of gas through it. The element has an outer sheet metal box, open at one end, and a refractory filling in the box comprising at least one brick spaced from the closed end of the box, into which a gas inlet opens. The brick contacts the metal sidewalls of the box and has grooves to allow the gas to pass to the open end of the box.

Abstract: In a process of hot-rolling steel wherein use is made of a heat-reflecting screen (13) by which heat radiating from the work (1) is reflected back to the work, the invention comprises the step of cooling the heat-reflecting-surface (10) of the screen during use, e.g. by flowing fluid coolant along the paths (18) in heat-conducting relationship to such heat-reflecting surface.

Abstract: A hot metal car is used for the transport of molten pig iron from a blast furnace to a steel making plant, the car having an opening through which it is filled and emptied. To restrict heat loss from the car, the opening is closed during at least one of (a) the journey from the blast furnace station to the steel making plant and (b) the journey from the steel making plant back to the blast furnace by a disposable cover which is at least partly lost into the molten iron during the course of the emptying or filling of the car at the end of the journey concerned.

Abstract: In an arrangement for mixing a first gas into a main flow of a second gas, comprising a main conduit for said main flow and a plurality of supply conduits for the first gas which open into said main conduit, the supply conduits are arranged as at least one set of three outlet openings. This set consists of a first opening which opens into the main flow perpendicularly to the main conduit wall and two second openings which are arranged so as each to provide a lesser flow rate of the first gas than the first opening and are offset with respect to the first opening. The three openings of the set thus direct the first gas into two contra-rotating circulatory movements, as viewed in the direction of the axis of the main conduit. This mixing arrangement is applicable for example to mixing a hot gas into the gas obtained from an ore pellet drying bed and to mixing a hot gas into a water-laden gas from a desulphurization plant.

Abstract: A process for monitoring the wear of a refractory lining of a metallurgical furnace wall during use of the furnace, it is sought to improve the reliability and accuracy of the measurement comprising the following steps:(1) arranging a bar of ceramic material in the wall so that the bar has an inner end at the inner face of the lining and extends to the exterior of the wall, the bar thus being subjected to wear at its inner end as the lining wears and determining(2) the position of the worn inner end of the bar ultrasonically by generating ultrasonic pulses in the bar and detecting the reflection of the pulses from the worn inner end of the bar.

Abstract: A method of producing steel by the LD process using a metallurgical vessel by blowing gas through an oxygen lance onto the top of the molten metal bath in the vessel for a period of time and during the final portion of the period blowing nitrogen directly into the metal bath through a gas-transmitting wall element. The duration of the final portion is from 0 to 2 minutes. The rate of gas supply through the wall element during the final portion is 5 to 8 Nm.sup.3 /h per ton of metal in the vessel.This is a division of application Ser. No. 440,401 filed Nov. 9, 1982, pending.

Abstract: A process of producing steel in a converter, wherein the starting materials comprise pig iron and ferrous scrap, involves blowing of oxygen into the molten metal bath in the converter. Advantageous results, in particular savings of Fe and Mn and in the amount of liquid metal used, are obtained by the combination of the following process steps:(a) during at least part of the time of blowing oxygen into the bath, inert gas is passed through the bottom of converter into the bath,(b) during at least part of the time of blowing oxygen into the bath, secondary oxygen is blown into the atmosphere above the bath,(c) at least once during the time of blowing oxygen into the bath, carbon is added to the reaction from above.