Patents Assigned to Sigri GmbH
  • Patent number: 5104518
    Abstract: Carbonates, oxides, carbides or fluorides of alkaline earth metals are added to coal tar pitches before coking. After the coking, which is preferably carried out by the delayed coking process, this produces coal tar pitch cokes or coal tar pitch needle cokes which have no irreversible expansion or a strongly reduced irreversible expansion upon heating in the temperature range of 1400.degree. to 2000.degree. C.
    Type: Grant
    Filed: March 6, 1990
    Date of Patent: April 14, 1992
    Assignee: Sigri GmbH
    Inventor: Hubert Jager
  • Patent number: 5068026
    Abstract: The process produces carbon bodies from coal tar pitch coke which have a strongly reduced or no irreversible thermal expansion in the temperature range of 1400.degree. to 2000.degree. C. Before shaping, a sulphonate, carboxylate or phenolate of an alkaline earth metal which is at least partially soluble in the binder is added to the mixing constituents which consist of particulate coke and a cokable binder as raw materials. After the mixing, shaping and firing, bodies are obtained which have only slight puffing upon graphitization.
    Type: Grant
    Filed: March 6, 1990
    Date of Patent: November 26, 1991
    Assignee: SIGRI GmbH
    Inventors: Hubert Jager, Alfred Lorenz
  • Patent number: 4941692
    Abstract: Carbon or graphite tubes which are mutually connected by an adhesive connection are less stressable than individual tubes. A sleeve formed of fibers and impregnated with a thermoplast is pulled onto the connection position. The new connection increases the stressability of connected tubes. The thermoplast limits the build up of stressing so that the reduction factor of the strength of the connection amounts only to 10 to 15%.
    Type: Grant
    Filed: May 22, 1989
    Date of Patent: July 17, 1990
    Assignee: SIGRI GmbH
    Inventors: Kurt Schaffner, Adolf Swozil, Gerhard Ullmann
  • Patent number: 4921283
    Abstract: Carbon or graphite tubes which are mutually connected by bonding are less highly stressable than individual tubes. A sleeve formed of fibers is drawn on to the connection location of the tubes. An intermediate section of the sleeve is firmly connected with the tubes. Foils are introduced between end sections of the sleeve and the tubes. The foils are displaceable in the direction of the tube axes. This structure increases the resistance of the connected tubes to stress. The strength reduction factor of the connection is about 10% as compared to the tubes alone.
    Type: Grant
    Filed: May 22, 1989
    Date of Patent: May 1, 1990
    Assignee: SIGRI GmbH
    Inventors: Kurt Schaffner, Adolf Swozil, Gerhard Ullmann
  • Patent number: 4903641
    Abstract: A method and apparatus for generating saturated steam by the combustion of chlorine and hydrogen to produce hydrogen chloride gas includes combusting chlorine and hydrogen to produce hydrogen chloride gas in an elongated synthesis oven having an upper segment, a lower segment and a middle segment having a walll in the form of a heat exchanger. A heat transfer medium is recirculated between the heat exchanger and a steam generator while heating the heat transfer medium to between 170.degree. and 230.degree. C. by heat exchange between the heat of the combustion and the heat transfer medium. Saturated steam is generated from water at a pressure of at least 7 bar in the steam generator.
    Type: Grant
    Filed: February 27, 1989
    Date of Patent: February 27, 1990
    Assignee: Sigri GmbH
    Inventors: Eduard Gohl, Johann Muller, Alois Spaderna
  • Patent number: 4716572
    Abstract: Coating graphite and carbon bodies with a protective layer containing predominantly silicon, by plasma spraying a silicon powder with a grain size under 0.05 mm and with an argon/hydrogen mixture as the plasma gas at reduced atmospheric pressure of at most 200 h Ps. The layer thickness is 0.1 to 0.5 mm and has a density which is at least 95% of the theoretical density. The coated bodies, for instance, graphite electrodes have a lower burnoff rate than unprotected ones in an oxidizing or corrosive atmosphere.
    Type: Grant
    Filed: December 17, 1985
    Date of Patent: December 29, 1987
    Assignee: Sigri GmbH
    Inventors: Heinrich Kuhn, Olaf Stitz, Karl Wimmer
  • Patent number: 4698189
    Abstract: Manufacture of vitreous carbon bodies in which thermoplastic materials containing aromatic groups are formed into bodies, are thermally stabilized by irradiation with ionizing radiation and are carbonized by heating them in an inert atmosphere.
    Type: Grant
    Filed: January 17, 1986
    Date of Patent: October 6, 1987
    Assignee: SIGRI GmbH
    Inventor: Ernst Tetzlaff
  • Patent number: 4691324
    Abstract: Connection between the sections of a graphite electrode in whose faces a socket is sunk to accommodate a threaded nipple. The socket base has a rotation-symmetrical recess whose principal sections are defined by a second or higher order curves and go over into the socket generating surface continuously differentiably. The annular stress active in the connection zone is reduced in particular by the recess.
    Type: Grant
    Filed: February 26, 1986
    Date of Patent: September 1, 1987
    Assignee: Sigri GmbH
    Inventor: Gunter Kraus
  • Patent number: 4663010
    Abstract: Anode, especially for the electrowinning of metals and metal compounds, formed of titanium alloy containing 0.5 to 5% nickel, 1 to 10% manganese and the remainder titanium.
    Type: Grant
    Filed: April 24, 1986
    Date of Patent: May 5, 1987
    Assignee: Sigri GmbH
    Inventors: Heiner Debrodt, Petra Kluger, Dieter Lieberoth
  • Patent number: 4651655
    Abstract: Dissolving salt encrustations which are deposited by exceeding the saturation limit from a gas saturated with water vapor on the heat exchanging surfaces of a heat exchanger, by passing the gas through a heat exchanger subdivided into several sections. The predominant part of the sections is subjected to a hot fluid heating the gas saturated with water vapor and the smaller part of the sections to a cold fluid for cooling the gas below the dew point. The salt crust is dissolved in the cooled sections by the separated condensation water and the salt solution is drained from the heat exchanger. After the salt crust is removed, the cooled sections are subjected to the hot fluid and parts of the heated sections to the cold fluid.
    Type: Grant
    Filed: March 4, 1986
    Date of Patent: March 24, 1987
    Assignee: Sigri GmbH
    Inventor: Jurgen Kunzel
  • Patent number: 4641321
    Abstract: Furnace head for heavy-current resistance furnaces of refractory masonry and at least one cooled electrode inserted into the masonry. Cooling devices extending over the entire length of the electrode are inserted into the latter and the temperature of the electrode can be set by controlling the cooling to the temperature of the masonry.
    Type: Grant
    Filed: July 22, 1985
    Date of Patent: February 3, 1987
    Assignee: Sigri GmbH
    Inventor: Jurgen Semmler
  • Patent number: 4639930
    Abstract: Port for a longitudinal or Castner-type graphitizing furnace, the masonry of which consists of a bottom section, lateral blocks and a yoke. The electrode rests on the bottom section and is pressed by the superimposed yoke against the bottom section. The lateral blocks are clamped to the electrode. Horizontal or vertical gaps cannot develop between the electrode and the masonry of the port in the operation of the graphitizing furnace.
    Type: Grant
    Filed: February 7, 1985
    Date of Patent: January 27, 1987
    Assignee: Sigri GmbH
    Inventor: Ulrich Kandzia
  • Patent number: 4629280
    Abstract: Connections between sections having thread sockets at the end face of carbon or graphite electrode by a double-conical threaded nipple screwed into the sockets in which the cone halves of the nipple are different in height.
    Type: Grant
    Filed: December 17, 1985
    Date of Patent: December 16, 1986
    Assignee: Sigri GmbH
    Inventors: Jurgen Semmler, Gunter Kraus
  • Patent number: 4615379
    Abstract: A corrosion-resistant storage body for a regenerator includes a multiplicity of carbon shapes having profiles formed thereon, the shapes being stacked together with the profiles spacing the shapes apart defining canals between the shapes passing through the storage body, and a frame holding the stacked shapes together.
    Type: Grant
    Filed: June 5, 1985
    Date of Patent: October 7, 1986
    Assignee: Sigri GmbH
    Inventor: Jurgen Kunzel
  • Patent number: 4594722
    Abstract: Graphite electrode for arc furnaces composed of a plurality of graphite electrode parts comprising a plurality of electrode sections connected by threaded graphite nipples, wherein at least one part of a graphite electrode has a plurality of graphite-filament yarn tensionally connected to the electrode part.
    Type: Grant
    Filed: May 17, 1985
    Date of Patent: June 10, 1986
    Assignee: Sigri GmbH
    Inventor: Horst Boder
  • Patent number: 4589967
    Abstract: Cell for the fusion-electrolytic production of aluminum which consists of a steel shell lined with graphite blocks, a heat-retarding insulation layer between the shell and the lining and cathodic bus bars inserted into the lining. Features of the invention are(a) the lining consists of graphite blocks with a heat conductivity of 80 to 120 W/m.multidot.K, an electric resistivity from 6 to 13 .mu..OMEGA.m and an accessible pore volume of at most 22%,(b) the insulating layer contains at least two partial layers with a heat conductivity of 0.1 to 0.2 and 0.8 to 1.2 W/m.multidot.K,(c) the thickness ratio of the lining and the insulating layer is 1.5 to 3.0.
    Type: Grant
    Filed: July 9, 1984
    Date of Patent: May 20, 1986
    Assignee: Sigri GmbH
    Inventor: Karl W. F. Etzel