Patents Assigned to Zircotube
  • Patent number: 5946365
    Abstract: A tubular blank (22) is rolled on a mandrel (14) in a pilgrim rolling mill. In a first rolling stage, a first part of the blank (22) is rolled on a first part (18,19) of the mandrel (14), with a reduction of the outside diameter of the blank (22) to the outside diameter of the guide tube and a reduction of the wall thickness of the blank (22) to one of a first wall thickness (e1) and a second wall thickness (e2) exceeding the first wall thickness (e1). The mandrel (14) is advanced in the axial direction. A second part of the blank (22) is rolled on a second part (20,21) of the mandrel spaced from the first part in the axial direction with a reduction of the outside diameter of the blank to the outside diameter of the guide tube and a reduction of the wall thickness of the blank (22) to the other of the first wall thickness (e1) and second wall thickness (e2).
    Type: Grant
    Filed: January 6, 1998
    Date of Patent: August 31, 1999
    Assignee: Zircotube
    Inventors: Jean Drillon, Jean-Luc Aubin
  • Patent number: 5788935
    Abstract: A substantial part of the water contained in the spent solution is evaporated under vacuum in an evaporator (7) and is then condensed, so as to obtain slightly acidic water and a concentrated acidic solution polluted by zirconium fluoride ZrF.sub.4. The polluted concentrated acidic solution is treated by evaporation under vacuum in a crystallizer (8), so as to obtain zirconium fluoride ZrF.sub.4 crystals and a purified concentrated acidic solution. The slightly acidic water and the purified concentrated acidic solution are mixed in desired proportions in order to obtain a regenerated pickling solution.
    Type: Grant
    Filed: January 24, 1996
    Date of Patent: August 4, 1998
    Assignee: Zircotube
    Inventor: Bernard Furic
  • Patent number: 5735978
    Abstract: A method of manufacturing a tube suitable for use as sheath of a nuclear fuel rod zirconium based alloy. The alloy contains 0.18% to 0.25% iron, 0.07% to 0.13% chromium, 0.35% to 1.70% tin, all percentages by weight, 900 ppm to 2300 ppm oxygen, 80 ppm to 200 ppm carbon, and 50 ppm to 120 ppm silicon. A drawn blank is subjected to successive passes of metallurgical treatment and of heat treatment. The Fe/Cr ratio by weight in the alloy lies in the range 1.6 to 3. The heat treatment includes, after at least one rolling pass, a plurality of annealing passes under an inert atmosphere such that the sum .SIGMA.A is greater than 1.5.10.sup.-17, and advantageously in the range 2.10.sup.-17 to 2.10.sup.-16. The first rolling pass is performed on the tube coming from the drawing operation, without an intermediate annealing. .SIGMA.A designates the sum of the products of the times t (in hours) multiplied by the exponential of --Q/RT, where T is the temperature in K.
    Type: Grant
    Filed: October 11, 1996
    Date of Patent: April 7, 1998
    Assignees: Framatome, Compagnie Generale des Matieres Nuclearies, Cezus, Zircotube
    Inventors: Jean-Paul Mardon, Jean Senevat, Daniel Charquet
  • Patent number: 5577088
    Abstract: The tubular cladding (1) comprises an internal surface of substantially prismatic shape, having successive faces. An ultrasonic examination head (3) makes it possible to emit ultrasound waves in the form of pulses from the outside of the cladding (1), so that the ultrasound waves pass through the wall of the cladding (1) and scan the wall over its entire periphery. The frequency of the ultrasound pulses is adjusted as a function of the circumferential scanning speed of the cladding (1). An ultrasound signal reflected by the internal surface of the cladding (1) is recorded and the reflected signal is analyzed in order to examine the number and the amplitude of the faces and the variation in thickness of the tubular cladding (1) over one revolution.
    Type: Grant
    Filed: February 24, 1995
    Date of Patent: November 19, 1996
    Assignee: Zircotube
    Inventors: Jean Senevat, Christian Roy, Eric Lucas
  • Patent number: 5373541
    Abstract: A nuclear fuel rod cladding for a water moderated and nuclear reactor comprises an inner portion of Zircaloy 4 and an outer portion of a zirconium-based alloy which contains by weight, besides zirconium and unavoidable impurities:0.35% to 0.65% tin0.18% to 0.25% iron0.07% to 0.13% chromium, and0.19% to 0.23% oxygen,with the sum of the iron, chromium, tin, and oxygen contents being less than 1.26% by weight. It may alternatively or additionally comprise 0.80% to 1.20% by weight niobium and then the oxygen content is in the range 0.10% to 0.16% by weight. The thickness of the outer layer is 10% to 25% of the total thickness of the cladding. In a modification, up to 0.5% of iron, chromium, niobium is replaced by an equivalent content of vanadium.
    Type: Grant
    Filed: January 19, 1993
    Date of Patent: December 13, 1994
    Assignees: Framatome, Compagnie Generale des Matieres Nucleaires, Zircotube
    Inventors: Jean P. Mardon, Jean Senevat
  • Patent number: 5329561
    Abstract: The duplex tube (1) comprises a tubular core (2) and a cladding or covering layer (3) made from an alloy, the base metal of which is identical to the base metal of the alloy constituting the tubular core (2).
    Type: Grant
    Filed: February 12, 1993
    Date of Patent: July 12, 1994
    Assignees: Framatome, Cogema, Societe en nom Collectif Zircotube
    Inventor: Didier Desruelles
  • Patent number: 5023048
    Abstract: The fuel rod comprises a sheath having an inner tubular layer and an outer surface layer composed of zirconium alloys which differ from each other. The surface layer, whose thickness is between 10 to 25% of the total thickness of the wall of the sheath, is constituted by a zirconium-base alloy containing by weight 0.35 to 0.65% tin, 0.20 to 0.65% iron, 0.09 to 0.16% oxygen and niobium in a proportion of 0.35 to 0.65% or vanadium in a proportion of 0.25 to 0.35%. The inner layer may be constituted by an alloy such as Zircaloy 4 or a zirconium-niobium alloy.
    Type: Grant
    Filed: January 22, 1990
    Date of Patent: June 11, 1991
    Assignees: Framatome, Cogema, Compagnie Europeenne du Zirconium dite Cezus, Societe en Nom Collectif Zircotube
    Inventors: Jean-Paul Mardon, Daniel Charquet, Marc Perez, Jean Senevat