SU1008162A1 - Electrode for glass-melting furnace and method of producing same - Google Patents

Abstract

1, A glass-melting furnace electrode containing a block of tin oxide and a current lead with a contact element characterized in that in order to increase the output of the alloy with h-ilATESTU, (E tchk & 1 I | HLT I i, i ..., j ,. (.. reliability), The contact element is discharged from located in another shroud board, narrowed along a tapered surface, the outer one being made of an elastic material with a thermal expansion coefficient., 1.0-4.6 times larger coefficients of linear thermal expansion} of the block, and internal to c is completed by kr 1-it with one cut along the generatrix and an emphasis for the block 2. A method of manufacturing an electrode of a glass-melting furnace to heat & L to heat and press the contact prodela of Eladkn to the tin yarn short-colored tin yarn, which is increased by operational reliability, heating is carried out to 9OO-1O83 C in an inert atmosphere, and the pressure is carried out vp588) T by pressure 1, О-50О MPa.d

Description

1 The invention relates to the construction industry heap and materials, and, in particular, to devices and methods for producing electrodes for glass production. Izv (utena electrode, currently used in domestic electric glass furnaces, which contains a ceramic block made of tin oxide, a current lead made in the form of a stainless steel collet pipe with a pull-out strut rod. In the process of negotiating an electrode at the end of the block according to the diameter of the collet pipe A blind hole is drilled into which the current lead is inserted. The electrode furnace is brought to a predetermined temperature regime in an atmosphere of ambient air. At a temperature of about 85 ° C, which provides a reduction in the resistance to Tin oxide ores () to the level required for the electrode to work (O, O8-O, 1) y1O Ohm, the collet tube with the help of the spacer pull rod pressed against the wall of the blind hole in the block with a pressure less than 1, €) MPa to the wall of the block, and then connected to the power source 111. The known electrode does not have a sufficiently high reliability and stability of operation due to the formation of an oxide film on the surface of the collet tube at an operating temperature of 900 ° C and an increase in the contact resistances between hard drive and b eye. Under production conditions, the contact area often overheats and collapses. Electrode breakdown is also observed as a result of block cracking, when, in order to reduce the contact resistance, resist pressure is increased between the current supply collet tube and the wall of the mounting bore in the block. Reliable operation of the electrodes leads to premature breakdowns of electric furnace furnaces. Due to the unreliability of work, a known electrode cannot be used on furnaces for vitrifying radioactive waste, which exclude, in view of the safety of the operating personnel, the possibility of their inspection and preventive maintenance during operation. The closest 111 to the proposed property (:: , salt block 022 made of ox dp of tin, tokopodopod, vk; a humaming butt-clamping latch connected to a presser spring rt by a source of electrode pitches, a contact gasket made of plastically refractory metal, Between the pressure cover and the end of the block 121, in the process of assembling the electrode, a ceramic block of a stepped configuration is mechanically processed, after which it is installed on an electric glass furnace and removed to a predetermined temperature in an atmosphere of ambient air. using a spring and a cap, a contact gasket is pressed with a pressure of less than 1.0 MPa, and then connected to a source of electrical energy. Noble metals are used for plastic contact strips, since the use of non-precious metals leads to THEIR oxidation, an increase in the contact resistance, overheating of the pad, and the destruction of the electrode as a result of the leakage of the pad metal. Gasket metal leakage may occur during the electrode operation, when the block is partially eroded by the glass mass at the end of the block in contact with the gasket. The temperature reaches the melting point of the metal from which the gasket is withdrawn. In addition, the machining of a ceramic block complicates the manufacturing process of the electrode, the purpose of the invention is to increase the operational reliability. This goal is achieved by the fact that ... in the electrode of a glass melting furnace containing a block of tin oxide and a current lead with a contact element, the contact element is made up of retaining boards arranged one inside the other, which are conjugated along a conical surface material with a coefficient of lignear thermal expansion, is 1.0–4.6 times greater than the coefficients of the linear thermal expansion of the block, and B1-to-c is made with at least one section along the generator and support for the block. According to the method of the IOLE-11 of the electrode of a glass furnace of the furnace, by najp wa S3, press the contact (contact the block or the oxidoic-i, H.nv-: H1g to 9OO-11083C inert atmosphere) and pressure is carried out by pressure 1 ° -83 ° C. MPa. FIG. 1 shows the electrode, section; in fig. 2 - the same, section AA; in fig. 3 shows an embodiment of the electrode. The electrode contains a block of tin oxide 1 of circular or rectangular cross section, mounted in a masonry p & 2. Block 1 rests on an abutment 3 of the inner retaining belt 4, 4 and 4, via a terminal connection 5, is connected to the power cable 6. C 4 and the outer bandage C 7 are interconnected along the cone of the surface, placed in the tubular cooler 8 and form the current lead of the electrode. In c 4, there is at least one: a cut O along the generatrix for compensation of the size difference between block 1 and cage 4, as well as to compensate for the elongation of heat 4 when heated. In c 4, it is made of ductile metal, for example, of copper, but it can be made of different ductile metals, for example, of iron, nickel, coated with copper, or silver. C 7 is made of an elastic metal with a CLTR equal to (5О-23О) х, for example, from molybdenum, nickel alloys. The current lead may contain two (Fig. 1) or three (Fig. 3) retaining bands. When three retaining bands are used, the two outer surfaces 7 and 10 are made of elastic metal and conjugated along the conical surface and inner along C 11 — made of ductile metal — along the profile of the block 1, the RSLTR of which is usually (49–4 O) x Density (6.1-6.7) x The electrode is attached to the frame of the furnace 12 with the help of the cable 13 and the dielectric strip 14. The production of the electrode was carried out as follows. Into the cavity of the tubular cooler 8, the outer-in with 7 is inserted, the inner in with 4 and the block 1 of tin oxide up to the stop 3 in the cross-section 4. When assembling the electrode, the electrical unit 1 can be used without additional mechanical processing, t. e. Block 1 may have small pores on the surface, pits, scratches and technologically acceptable after firing, the distortion of geometrical dimensions is within the limits, usually 1 The assembly is heated in an electric furnace in an inert atmosphere, for example, nitrogen at a temperature lowering the resistance of the block of tin oxide to ohm m is lower. In practice, the assembly is heated to about 90 ° -10 ° -83 ° C — not higher than the temperature, the melting tours of the copper contact box 4, and then cooled to ambient temperature. Similarly, an assembly can be heated in a gas muffle furnace with natural gas combustion products during flameless gas combustion with an excess air ratio of 1, O1-1, and O4. The heated outer c 7 is expanded and, under the action of the weight of the block 1 or the additional load, is tightly fitted onto the block 1 with a contact 4, covering them. When the assembly is cooled to ambient temperature, the outside is at 7, due to more you-. CTL presses the contact across the 4 to the block 1, fill the surface shells and irregularities of the block 1 metals Saa 4. The pressure of the contact Sa 4 to the unit 1, which is (1, O-5OO) MPa, per - is lamented by the yield strength of material 4 and 4 of compressive strength of the material of unit 1, and the pressure value is determined with sufficient accuracy for practice by the amount of external surface deformation 7. In the electrodes manufactured according to the proposed technology between block 1 and contact spacer 4, to the block with pressure (1, O-5OO) MPa, p and ambient temperature is fixed elektrosoprotivletsho not prevyschayuschee (O, O-OO5 1) U1O ohms l closest to the electrical resistance, which has a block of at okaada ogyuva 9OO-1O83 ° C. It was found that with increasing temperature above 900 C, the resistance of ceramics from. tin oxide a decreases from a value of 0.1. Acceptable: the minimum value of the order of 0.005-10-2 Ohm.m at 1050-1060 ° C then increases slightly, reaching, in particular, a value around O, 0i4n Ohm м m at 1080 ° s Experimental samples of electrodes (tab 1) also had a lower electrical resistance when heating electrode assemblies in the at-atmosphere of nitrogen to 1050–1060 ° C in the process of manufacturing these electrodes. Approx. Experimental samples of electrodes were made on the basis of rods of tin oxide with a diameter of 10 mm and a length of 80 mm. 5l Rods had an average density of (6.38-.6.42) 1.CH. The results of measurements of the electrical resistance of five samples are listed in the table. The resistance of the rods of tin oxide and made of rods of the experimental electrodes at. heating them in a nitrogen atmosphere to a temperature of 9OO-1O8O ° C, followed by cooling to room temperature and final compression to 36 MPa. Experimental test electrodes (I for 10 ч h at 1150 ° C in a glass melt of the following composition, bes. - SO.OjNcijO - 26.0; Ae203 21, 0; fByO - 2.5; KiO - O, 5 on the surface of the birth element, the contacting glass was maintained at a level of up to 3 A / c. Experimental samples worked steadily for 1 0 h without any changes in the electrical parameter. , its fusion with a contact gasket and the formation of metaskshch; The contact between the block and the current lead, which is not achieved in the bulk medium, is limited by the concentration of the most dispersed tin in the proposed method. () The offered electrode and method of its manufacture have high reliability due to tight pressing of the contact gasket to the block, high current carrying capacity in the range of 25, due to low electrical resistance, exclude; The machinability of a ceramic block having a Mohs' hardness of 7 and having the ability to hammer in a cutting tool also eliminates the need to use precious metals.

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13О 900

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Claims (2)

1. The electrode of a glass melting furnace, containing a block of tin oxide and a current supply with a contact element, characterized in that in order to increase the operation ..... I. In terms of reliability, the contact element is made of bandage belts arranged in one another, mated along a conical surface, and the rifle belt is made of an elastic material with a coefficient of linear thermal expansion of 1.0-4.6 times greater than the coefficients of linear thermal expansion block, and the inner belt is made with at least one cut along the generatrix and focus for the block. Glass furnace 2. A method of producing an electrode by heating and pressing the contact pads to the block of tin oxide about Whitlock aspirants and in that, in order to increase operational reliability, the heating is carried out until ^J 900-1083 C in an inert atmosphere, and the pressing pressure is carried out 1.0-500 MPa.