WO1995024718A1 - Spacing grid for nuclear fuel-containing fuel rods of a nuclear reactor fuel element - Google Patents

Spacing grid for nuclear fuel-containing fuel rods of a nuclear reactor fuel element Download PDF

Info

Publication number
WO1995024718A1
WO1995024718A1 PCT/DE1995/000214 DE9500214W WO9524718A1 WO 1995024718 A1 WO1995024718 A1 WO 1995024718A1 DE 9500214 W DE9500214 W DE 9500214W WO 9524718 A1 WO9524718 A1 WO 9524718A1
Authority
WO
WIPO (PCT)
Prior art keywords
mesh
fuel
outer edge
corner
tongue
Prior art date
Application number
PCT/DE1995/000214
Other languages
German (de)
French (fr)
Inventor
Alexander Steinke
Original Assignee
Siemens Aktiengesellschaft
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Siemens Aktiengesellschaft filed Critical Siemens Aktiengesellschaft
Publication of WO1995024718A1 publication Critical patent/WO1995024718A1/en

Links

Classifications

    • G—PHYSICS
    • G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
    • G21C—NUCLEAR REACTORS
    • G21C3/00—Reactor fuel elements and their assemblies; Selection of substances for use as reactor fuel elements
    • G21C3/30—Assemblies of a number of fuel elements in the form of a rigid unit
    • G21C3/32—Bundles of parallel pin-, rod-, or tube-shaped fuel elements
    • G21C3/33—Supporting or hanging of elements in the bundle; Means forming part of the bundle for inserting it into, or removing it from, the core; Means for coupling adjacent bundles
    • G21C3/332—Supports for spacer grids
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E30/00—Energy generation of nuclear origin
    • Y02E30/30—Nuclear fission reactors

Definitions

  • the invention relates to a spacer grid for fuel rods of a nuclear reactor fuel element containing nuclear fuel according to patent claim 1.
  • a nuclear reactor fuel element which is intended for a pressurized water nuclear reactor, has a plurality of control rod guide tubes as rod-shaped bodies which are guided through the guide sleeves of the spacer grids.
  • These control rod guide tubes are attached at one end to a fuel element head and at the other end to a fuel element foot.
  • the spacer grids are located between the fuel assembly head and the fuel assembly foot and, viewed in the longitudinal direction of the nuclear reactor fuel assembly, are arranged next to one another at a distance from one another.
  • the control rod guide tubes are guided through the meshes of the spacer grids, but also the fuel rods containing nuclear fuel, which are neither attached to the fuel element head nor to the fuel element foot.
  • control rod guide tubes are generally attached to the guide sleeves in a form-fitting manner, the fuel rods in the individual meshes of the spacer grids are non-positively held with the aid of springs which press the fuel rods against rigid knobs on the mesh walls of the spacer grids.
  • the tongue drawn outwards at the sleeve end of the guide sleeve and fastened with its tongue edges to the inclined outer edge section of each of the two mesh walls of a stitch of the spacer grid according to the invention stiffens this spacer grid and the connection between the spacer grid and the guide sleeve to a particular degree. Lateral transverse forces that act on the fuel element head and While the nuclear reactor fuel element, which is firmly held in the element base, causes a lateral deflection path of the control discharge pipes together with the spacer grids and the fuel rods, these parts also assume their original shape again after the lateral forces have been eliminated or reversed.
  • Claims 2 to 4 are directed to advantageous further developments of the spacer grid according to the invention.
  • FIG. 1 schematically shows the side view of a nuclear reactor fuel element which is intended for a pressurized water nuclear reactor.
  • FIG. 2 shows an exploded view of a plan view of a spacer grid according to the invention of the nuclear reactor fuel element according to FIG. 1.
  • FIG. 3 shows a top view of the spacer grid according to FIG. 2 in the assembled state.
  • FIG. 4 shows the nuclear reactor fuel element according to FIG. 1 in a side view and in a deformed state.
  • the nuclear reactor fuel element according to FIG. 1 has a fuel element head 2 and a fuel element foot 3. Between focal element head 2 and fuel element foot 3, a control rod guide tube 4 can be seen.
  • This control rod guide tube is rigidly attached, for example screwed, at one end to the fuel assembly head 2 and at the other end to the fuel assembly foot 3.
  • FIG. 1 a number of spacer grids 5 can be seen in FIG. Both the fuel assembly head 2 and the fuel assembly foot 3 have also seen a distance from the spacer grids 5 in the direction of the longitudinal axis 6.
  • a guide sleeve 15 is rigidly attached to both the top and bottom of each spacer grating 5.
  • the control rod guide tube 4 extends through these two guide sleeves 15 on each of the spacer grids 5, and the control rod guide tube 4 is rigidly attached to each of these guide sleeves 15 by welding points.
  • the attachment of the control tube 4 to the guide sleeves 15 can also be positive.
  • a fuel rod 8 filled with nuclear fuel is guided through a large part of the grid meshes of each of the spacer grids 5.
  • This fuel rod 8 has a distance from the fuel element head 2 or fuel element foot 3 at each of its rod ends.
  • the spacer grids 5 have springs with associated rigid knobs on the mesh walls of grid meshes, by means of which the fuel rod 8 is held in a grid mesh on each spacer grid 5 in a force-locking manner .
  • the spacer grids 5 have grid meshes 9 with a square cross section.
  • two mesh walls 10 of such a grid mesh 9 abut one another along a corner edge 11.
  • An outer edge 12 of the two mesh walls 10 runs transversely to this corner edge 11 both on the upper and on the lower side of the spacer grid 5.
  • the outer edges on the underside of the Stand grids 5 are not recognizable in FIGS. 2 and 3.
  • Each of the four corner edges 11 of the mesh 9 forms a mesh corner both on the upper side and on the underside of the spacer grid 5. Both mesh corners are spaced apart from one another, and of both mesh corners only the mesh corner 13 can be seen in FIGS. 2 and 3 on the upper side of the spacer grating 5.
  • the outer edges 12 of two mesh walls 10 of the mesh 9 each have an outer edge section 14 on the corner edge 11, with which the two outer edges 12 meet in the mesh corner 13. In these outer edge sections 14, the outer edges 12 are inclined toward the other mesh corner, which is located on the corner edge 11 on the other side of the spacer grid 5.
  • a hollow-cylindrical guide sleeve 15 for a control rod guide tube 4 has four outwardly drawn tongues 16 on one sleeve end, of which only three tongues are visible in FIGS. 2 and 3. With respect to the central axis of the guide sleeve 15, these tongues 16 are each at an angular distance of 90 °.
  • the tongue edges 16a and 16b are of equal length and form an acute angle with one another, i.e. each tongue 16 represents an acute-angled, isosceles triangle.
  • Each tongue 16 is one between its
  • Tongue edges 16a and 16b running direction 16c are convexly curved on the outside.
  • each of the four tongues 16 is welded to the inclined outer edge portion 14 of one of two mesh walls and the tongue edge 16b is welded to the inclined outer edge portion 14 of the other mesh wall 10 of these two mesh walls, which are the same in the same Hit corner edge 11 of mesh 9.
  • Each tongue 16 is thus arranged between the two outer edge sections 14 assigned to it.
  • this guide sleeve 15 can be rigidly welded to a control rod guide tube that passes through it.
  • Nuclear reactor can also cause a lateral force F and thus lateral deflection paths s of the spacer grids 5.
  • curve I shows the course of the deflection path s recognizable in FIG. 4 as a function of the
  • This curve I passes through the zero point of the coordinate system, i.e. there is no final deformation of the nuclear reactor fuel element, which would also include a hysteresis loop II shown in FIG. 5.

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Plasma & Fusion (AREA)
  • General Engineering & Computer Science (AREA)
  • High Energy & Nuclear Physics (AREA)
  • Monitoring And Testing Of Nuclear Reactors (AREA)

Abstract

A stiff spacing grid has a mesh (9) with two walls (10) adjacent to a corner (11) of the mesh (9). The walls (10) have outer edges (12) that extend transversely to the corner (11) and that meet at a first corner point (13) of the corner (11). One outer edge (12) is associated with the first wall (10) and the other outer edge (12) is associated with the other wall (10). Each outer edge (12) has a section (14) at the corner (11) which is inclined toward the other corner point (13) of the mesh. In addition, a guiding sleeve (15) is provided for a rod-shaped body. One end of the sleeve has an outwardly projecting tongue (16) whose edges (16a, 16b) are secured to sections (14) of the outer edges of both mesh walls (10).

Description

Beschreibungdescription
Abstandhaltergitter für Kernbrennsto f enthaltende Brennstäbe eines KernreaktorbrennelementsSpacer grid for fuel rods containing a nuclear reactor fuel element
Die Erfindung betrifft ein Abstandhaltergitter für Kernbrenn¬ stoff enthaltende Brennstäbe eines Kernreaktorbrennelements nach Pate tanspruch 1.The invention relates to a spacer grid for fuel rods of a nuclear reactor fuel element containing nuclear fuel according to patent claim 1.
Insbesondere ein Kernrekatorbrennelement, das für einen Druckwasserkernreaktor bestimmt ist, weist mehrere Steuer¬ stabführungsrohre als stabförmige Körper auf, die durch die Führungshülsen der Abstandhaltergitter geführt sind. Diese Steuerstabführungsrohre sind mit einem Ende an einem Bren¬ nelementkopf und mit dem anderen Ende an einem Brennelement- fuß befestigt. Zwischen Brennelementkopf und Brennelementfuß befinden sich die Abstandhaltergitter, die in Längsrichtung des Kernreaktorbrennelements gesehen nebeneinander mit Ab- stand voneinander angeordnet sind. Durch die Maschen der Ab¬ standhaltergitter sind nicht nur die Steuerstabführungsrohre geführt, sondern auch die Kernbrennstoff enthaltenden Brenn¬ stäbe, die weder am Brennelementkopf noch am Brennelementfuß befestigt sind. Während die Steuerstabführungsrohre in der Regel an den Führungshülsen formschlüssig befestigt sind, sind die Brennstäbe in den einzelnen Maschen der Abstandhal¬ tergitter kraftschlüssig mit Hilfe von Federn gehaltert, die die Brennεtäbe gegen starre Noppen an den Maschenwänden der Abstandhaltergitter pressen.In particular, a nuclear reactor fuel element, which is intended for a pressurized water nuclear reactor, has a plurality of control rod guide tubes as rod-shaped bodies which are guided through the guide sleeves of the spacer grids. These control rod guide tubes are attached at one end to a fuel element head and at the other end to a fuel element foot. The spacer grids are located between the fuel assembly head and the fuel assembly foot and, viewed in the longitudinal direction of the nuclear reactor fuel assembly, are arranged next to one another at a distance from one another. Not only the control rod guide tubes are guided through the meshes of the spacer grids, but also the fuel rods containing nuclear fuel, which are neither attached to the fuel element head nor to the fuel element foot. While the control rod guide tubes are generally attached to the guide sleeves in a form-fitting manner, the fuel rods in the individual meshes of the spacer grids are non-positively held with the aid of springs which press the fuel rods against rigid knobs on the mesh walls of the spacer grids.
Die am Hülsenende der Führungshülse nach außen gezogene und mit ihren Zungenkanten an den geneigten Außenkantenabschnitt jeder der beiden Maschenwände einer Masche des erfindungsge¬ mäßen Abstandhaltergitters befestigte Zunge versteift dieses Abstandhaltergitter und die Verbindung zwischen dem Abstand¬ haltergitter und der Führungshülse in besonderem Maße. Seit¬ liche Querkräfte, die auf das an Brennelementkopf und Bren- nelementfuß fest gehalterte Kernreaktorbrennelement einwir¬ ken, rufen deshalb zwar einen seitlichen Auslenkweg der Steu¬ erstabführungsrohre samt den Abstandhaltergittern und den Brennstäben hervor, nach Wegfall oder Umkehr der seitlichen Querkräfte nehmen diese Teile aber auch wieder ihre ursprüng¬ liche Ausgangsform an. Eine Hysterese von seitlicher Quer¬ kraft über dem seitlichen Auslenkweg, die dazu führen würde, daß die Steuerstabführungsrohre, Abstandhaltergitter und Brennstäbe nie wieder in ihre Ausgangsform zurückfänden, wird also vermieden. Eine endgültige und daher unerwünschte Ver¬ formung des gesamten Kernreaktorbrennelements kann somit nicht eintreten.The tongue drawn outwards at the sleeve end of the guide sleeve and fastened with its tongue edges to the inclined outer edge section of each of the two mesh walls of a stitch of the spacer grid according to the invention stiffens this spacer grid and the connection between the spacer grid and the guide sleeve to a particular degree. Lateral transverse forces that act on the fuel element head and While the nuclear reactor fuel element, which is firmly held in the element base, causes a lateral deflection path of the control discharge pipes together with the spacer grids and the fuel rods, these parts also assume their original shape again after the lateral forces have been eliminated or reversed. A hysteresis of lateral transverse force over the lateral deflection path, which would lead to the control rod guide tubes, spacer grids and fuel rods never being returned to their original shape, is thus avoided. A final and therefore undesirable deformation of the entire nuclear reactor fuel element cannot therefore occur.
Die Patentansprüche 2 bis 4 sind auf vorteilhafte Weiterbil- düngen des erfindungsgemäßen Abstandhaltergitters gerichtet.Claims 2 to 4 are directed to advantageous further developments of the spacer grid according to the invention.
Die Erfindung und ihre Vorteile seien anhand der Zeichnung an einem Ausführungsbeispiel näher erläutert:The invention and its advantages are explained in more detail with reference to the drawing using an exemplary embodiment:
FIG 1 zeigt εchematisch die Seitenansicht eines Kernreaktor¬ brennelements, das für einen Druckwasserkernreaktor bestimmt ist .1 schematically shows the side view of a nuclear reactor fuel element which is intended for a pressurized water nuclear reactor.
FIG 2 zeigt in Exploεionsdarstellung eine Draufsicht auf ein erfindungsgemäßes Abstandhaltergitter des Kernreaktorbrenn¬ elements nach Figur 1.2 shows an exploded view of a plan view of a spacer grid according to the invention of the nuclear reactor fuel element according to FIG. 1.
FIG 3 zeigt in Draufsicht das Abstandhaltergitter nach Figur 2 im montierten Zustand.3 shows a top view of the spacer grid according to FIG. 2 in the assembled state.
FIG 4 zeigt in Seitenansicht und verformtem Zustand das Kern¬ reaktorbrennelement nach Figur 1.FIG. 4 shows the nuclear reactor fuel element according to FIG. 1 in a side view and in a deformed state.
FIG 5 zeigt zwei Auslenkweg-Querkraft-Kurven.5 shows two deflection-lateral force curves.
Das Kernreaktorbrennelement nach Figur 1 weist einen Brenn¬ elementkopf 2 und ein Brennelementfuß 3 auf. Zwischen Brenn- elementkopf 2 und Brennelementfuß 3 ist ein Steuerstabfüh¬ rungsrohr 4 erkennbar. Dieses Steuerstabführungsrohr ist mit einem Ende am Brennelementkopf 2 und mit dem anderen Ende am Brennelementfuß 3 starr befestigt, z.B. festgeschraubt.The nuclear reactor fuel element according to FIG. 1 has a fuel element head 2 and a fuel element foot 3. Between focal element head 2 and fuel element foot 3, a control rod guide tube 4 can be seen. This control rod guide tube is rigidly attached, for example screwed, at one end to the fuel assembly head 2 and at the other end to the fuel assembly foot 3.
Ferner sind in Figur 1 mehrere Abstandhaltergitter 5 erkenn¬ bar, die in Richtung der Längsachse 6 des Kernreaktorbrenn- elementε gesehen nebeneinander mit Abstand angeordnet sind. Sowohl der Brennelementkopf 2 alε auch der Brennelementfuß 3 haben ebenfalls Abstand von den Abstandhaltergittern 5 in Richtung der Längsachse 6 gesehen.Furthermore, a number of spacer grids 5 can be seen in FIG. Both the fuel assembly head 2 and the fuel assembly foot 3 have also seen a distance from the spacer grids 5 in the direction of the longitudinal axis 6.
Sowohl an der Ober- als auch an der Unterseite jedes Abstand¬ haltergitters 5 ist eine Führungshülse 15 starr befestigt. Durch diese beiden Führungshülεen 15 an jedem der Abstandhal¬ tergitter 5 erstreckt sich das Steuerstabführungsrohr 4, und an jeder dieser Führungshülεen 15 iεt daε Steuerstabführungs¬ rohr 4 durch Schweißpunkte starr befestigt. Die Befestigung deε Steuerεtabführungsrohrs 4 an den Führungshülsen 15 kann auch formschlüssig sein.A guide sleeve 15 is rigidly attached to both the top and bottom of each spacer grating 5. The control rod guide tube 4 extends through these two guide sleeves 15 on each of the spacer grids 5, and the control rod guide tube 4 is rigidly attached to each of these guide sleeves 15 by welding points. The attachment of the control tube 4 to the guide sleeves 15 can also be positive.
Durch einen großen Teil der Gittermaschen jedes der Abstand¬ haltergitter 5 ist jeweils ein mit Kernbrennstoff gefüllter Brennstab 8 geführt. Dieser Brennstab 8 hat an jedem εeiner Stabenden Abstand vom Brennelementkopf 2 bzw. Brennelementfuß 3. Ferner weisen die Abstandhaltergitter 5 Federn mit zuge¬ ordneten starren Noppen an Maschenwänden von Gittermaschen auf, mit denen der Brennstab 8 an jedem Abstandhaltergitter 5 in einer Gittermaεche kraftεchlüssig gehaltert iεt.A fuel rod 8 filled with nuclear fuel is guided through a large part of the grid meshes of each of the spacer grids 5. This fuel rod 8 has a distance from the fuel element head 2 or fuel element foot 3 at each of its rod ends. Furthermore, the spacer grids 5 have springs with associated rigid knobs on the mesh walls of grid meshes, by means of which the fuel rod 8 is held in a grid mesh on each spacer grid 5 in a force-locking manner .
Wie die Figuren 2 und 3 zeigen, haben die Abεtandhaltergitter 5 Gittermaschen 9 mit quadratischem Querschnitt. Jeweils zwei Maschenwände 10 einer solchen Gittermasche 9 stoßen längs ei¬ ner Eckkante 11 aneinander. Quer zu dieser Eckkante 11 ver- läuft sowohl an der Ober- als auch an der Unterseite des Ab¬ standhaltergitters 5 jeweils eine Außenkante 12 der beiden Maschenwände 10. Die Außenkanten an der Unterseite des Ab- standhaltergitters 5 sind in den Figuren 2 und 3 nicht er¬ kennbar.As FIGS. 2 and 3 show, the spacer grids 5 have grid meshes 9 with a square cross section. In each case two mesh walls 10 of such a grid mesh 9 abut one another along a corner edge 11. An outer edge 12 of the two mesh walls 10 runs transversely to this corner edge 11 both on the upper and on the lower side of the spacer grid 5. The outer edges on the underside of the Stand grids 5 are not recognizable in FIGS. 2 and 3.
Jede der vier Eckkanten 11 der Maεche 9 bildet εowohl an der Oberεeite als auch an der Unterseite deε Abstandhaltergitters 5 eine Maschenecke. Beide Maschenecken sind voneinander beab¬ standet, und von beiden Maschenecken iεt in Figur 2 und 3 nur die Maεchenecke 13 an der Oberεeite deε Abεtandhaltergitterε 5 erkennbar. Jeweils die Außenkanten 12 von zwei Maschenwän- den 10 der Masche 9 weisen an der Eckkante 11 einen Außenkan- tenabεchnitt 14 auf, mit dem sich die beiden Außenkanten 12 in der Maschenecke 13 treffen. In dieεen Außenkantenabschnit¬ ten 14 sind die Außenkanten 12 zur anderen Maschenecke hin geneigt, die sich auf der Eckkante 11 auf der anderen Seite des Abstandhaltergitterε 5 befindet.Each of the four corner edges 11 of the mesh 9 forms a mesh corner both on the upper side and on the underside of the spacer grid 5. Both mesh corners are spaced apart from one another, and of both mesh corners only the mesh corner 13 can be seen in FIGS. 2 and 3 on the upper side of the spacer grating 5. The outer edges 12 of two mesh walls 10 of the mesh 9 each have an outer edge section 14 on the corner edge 11, with which the two outer edges 12 meet in the mesh corner 13. In these outer edge sections 14, the outer edges 12 are inclined toward the other mesh corner, which is located on the corner edge 11 on the other side of the spacer grid 5.
Eine hohlzylinderför ige Führungεhülse 15 für ein Steuerstab¬ führungsrohr 4 weist an einem Hülsenende vier nach außen ge¬ zogene Zungen 16 auf, von denen in den Figuren 2 und 3 nur drei Zungen sichtbar sind. In bezug auf die Mittelachse der Führungshülse 15 haben diese Zungen 16 voneinander jeweils einen Winkelabstand von 90°. Die Zungenkanten 16a und 16b sind gleich lang und bilden miteinander einen spitzen Winkel, d.h. jede Zunge 16 stellt ein spitzwinkliges, gleichschenkli- geε Dreieck dar. Jede Zunge 16 iεt um eine zwischen ihrenA hollow-cylindrical guide sleeve 15 for a control rod guide tube 4 has four outwardly drawn tongues 16 on one sleeve end, of which only three tongues are visible in FIGS. 2 and 3. With respect to the central axis of the guide sleeve 15, these tongues 16 are each at an angular distance of 90 °. The tongue edges 16a and 16b are of equal length and form an acute angle with one another, i.e. each tongue 16 represents an acute-angled, isosceles triangle. Each tongue 16 is one between its
Zungenkanten 16a und 16b verlaufende Richtung 16c an der Au¬ ßenseite konvex gewölbt.Tongue edges 16a and 16b running direction 16c are convexly curved on the outside.
Wie Figur 3 zeigt, ist die eine Zungenkante 16a jeder der vier Zungen 16 mit dem geneigten Außenkantenabschnitt 14 der einen von zwei Maschenwänden und die Zungenkante 16b mit dem geneigten Außenkantenabschnitt 14 der anderen Maschenwand 10 dieser zwei Maschenwände verschweißt, die sich in der glei¬ chen Eckkante 11 der Gittermasche 9 treffen. Jede Zunge 16 ist also zwischen den beiden ihr zugeordneten Außenkantenab¬ schnitten 14 angeordnet. An in Figur 3 angedeuteten Punktschweißstellen 17 außen am Mantel der Führungshülse 15 kann diese Führungshülse 15 mit einem durch sie hindurchgeführten Steuerstabführungsrohr starr verschweißt sein.As FIG. 3 shows, the one tongue edge 16a of each of the four tongues 16 is welded to the inclined outer edge portion 14 of one of two mesh walls and the tongue edge 16b is welded to the inclined outer edge portion 14 of the other mesh wall 10 of these two mesh walls, which are the same in the same Hit corner edge 11 of mesh 9. Each tongue 16 is thus arranged between the two outer edge sections 14 assigned to it. At the spot welding points 17 indicated in FIG. 3 on the outside of the jacket of the guide sleeve 15, this guide sleeve 15 can be rigidly welded to a control rod guide tube that passes through it.
In anderen Gittermaschen 9 deε Abεtandhaltergitters 5 nach den Figuren 2 und 3 sind an Maschenwänden ausgebildete starre Noppen 18 erkennbar, denen Federn 19 an gegenüberliegenden Maεchenwänden zugeordnet εind. Diese starre Noppen 18 dienen zusammen mit den Federn 19 zum kraftschlüεεigen Haltern eines Brennstabeε 8 in der jeweiligen Gittermasche 9.In other lattice meshes 9 of the spacer lattice 5 according to FIGS. 2 and 3, rigid knobs 18 formed on mesh walls can be seen, to which springs 19 on opposite mesh walls are assigned. These rigid knobs 18, together with the springs 19, serve to hold a fuel rod 8 in the respective grid mesh 9 in a force-locking manner.
In Figur 4, in der gleiche Teile mit gleichen Bezugszeichen wie in Figur 1 versehen sind, können z.B. axiale Wärmedehnun- gen der Brennstäbe 8, die im Kernreaktor auftreten und die entsprechend dem Leistungεgradienten über den Querεchnitt deε Kernreaktorbrennelementε für die verschiedenen Brennεtäbe 8 deε Kernreaktorbrennelements verεchieden groß sind, eine Querkraft F und damit seitliche Auslenkwege s der Abstandhal- tergitter 5 bewirken. Auch der über den Querεchnitt des Kern¬ reaktorbrennelements unterschiedliche Neutronenfluß in einem Kernreaktor induziert verschiedenen starkes Längenwachstum der einzelnen Brennstäbe 8, was ebenfalls zu einer Querkraft F und damit zu seitlichen Auslenkwegen s der Abstandhaltger- gitter 5 führen kann. Querströmungen eines Kühlmittels imIn Figure 4, in which the same parts are provided with the same reference numerals as in Figure 1, e.g. axial thermal expansions of the fuel rods 8, which occur in the nuclear reactor and which differ in size according to the power gradient across the cross section of the nuclear reactor fuel element for the various fuel rods 8 of the nuclear reactor fuel element, cause a lateral force F and thus lateral deflection paths s of the spacer grids 5. The neutron flow in a nuclear reactor, which differs across the cross section of the nuclear reactor fuel element, also induces various strong longitudinal growths of the individual fuel rods 8, which can likewise lead to a lateral force F and thus to lateral deflection paths s of the spacer grids 5. Cross flows of a coolant in the
Kernreaktor können ebenfalls eine Querkraft F und damit seit¬ liche Auslenkwege s der Abstandhaltergitter 5 bewirken.Nuclear reactor can also cause a lateral force F and thus lateral deflection paths s of the spacer grids 5.
Im Diagramm nach Figur 5 zeigt die Kurve I den Verlauf deε in Figur 4 erkennbaren Auslenkwegs s in Abhängigkeit von derIn the diagram according to FIG. 5, curve I shows the course of the deflection path s recognizable in FIG. 4 as a function of the
Querkraft F an einem Kernreaktorbrennelement mit Abstandhal¬ tergittern entsprechend in den Figuren 2 und 3. Diese Kurve I durchläuft den Nullpunkt des Koordinatenεystems, d.h. eine endgültige Verformung deε Kernreaktorbrennelementε, zu der eine in Figur 5 ebenfallε eingezeichnete Hystereseεchleife II gehören würde, findet nicht statt. Shear force F on a nuclear reactor fuel element with spacer grids in accordance with FIGS. 2 and 3. This curve I passes through the zero point of the coordinate system, i.e. there is no final deformation of the nuclear reactor fuel element, which would also include a hysteresis loop II shown in FIG. 5.

Claims

Patentansprüche claims
1. Abεtandhaltergitter für Kernbrennεtoff enthaltende Brenn¬ stäbe eines Kernreaktorbrennelementε1. Spacer grid for fuel rods of a nuclear reactor fuel element containing nuclear fuel
mit einer Gittermasche (9) , die zwei längs einer Eckkantewith a mesh (9), the two along a corner edge
(11) der Gittermasche (9) aneinanderstoßende Maεchenwände (10) mit zwei quer zur Eckkante (11) verlaufenden und sich in einer ersten von zwei beabstandeten Maschenecken (13) der Eckkante (11) treffenden Außenkanten (12) aufweist, von denen die eine Außenkante (12) der einen und die andere Außenkante(11) the mesh (9) abutting mesh walls (10) with two transverse to the corner edge (11) and in a first of two spaced mesh corners (13) of the corner edge (11) meeting outer edges (12), one of which Outer edge (12) of one and the other outer edge
(12) der anderen Maschenwand (10) zugeordnet ist und von de¬ nen jede Außenkante (12) an der Eckkante (11) einen Außenkan¬ tenabschnitt (14) aufweist, an dem diese Außenkante (12) zur anderen der beiden Maεchenecken (13) hin geneigt iεt, εowie(12) is assigned to the other mesh wall (10) and each outer edge (12) of which has an outer edge section (14) on the corner edge (11), on which this outer edge (12) to the other of the two mesh corners (13 ) inclined towards, as well
mit einer Führungshülse (15) für einen stabförmigen Körper, die an einem Hülεenende eine nach außen gezogene Zunge (16) aufweist, deren Zungenkanten (16a, 16b) an dem Außenkantenab- schnitt (14) jeder der beiden Maschenwände (10) befeεtigt iεt .with a guide sleeve (15) for a rod-shaped body, which has an outwardly drawn tongue (16) at one end of the sleeve, the tongue edges (16a, 16b) of which are attached to the outer edge section (14) of each of the two mesh walls (10).
2. Abεtandhaltergitter nach Anεpruch 1, bei dem die Zungen¬ kanten (16a, 16b) mit den Außenkantenabschnitten (14) ver- schweißt sind.2. Spacer grid according to claim 1, in which the tongue edges (16a, 16b) are welded to the outer edge sections (14).
3. Abstandhaltergitter nach einem der Ansprüche 1 und 2, bei dem die Zunge (16) um eine zwiεchen ihren Zungenkanten (16a, 16b) verlaufende Richtung (16c) an ihrer Außenεeite konvex gewölbt iεt.3. Spacer grid according to one of claims 1 and 2, in which the tongue (16) is convexly curved on its outer side around a direction (16c) extending between its tongue edges (16a, 16b).
4. Abεtandhaltergitter nach einem der Anεprüche 1 biε 3, bei dem die Zunge (16) zwischen den Außenkantenabschnitten (14) angeordnet iεt. 4. spacer grid according to one of claims 1 to 3, in which the tongue (16) is arranged between the outer edge sections (14).
PCT/DE1995/000214 1994-03-08 1995-02-20 Spacing grid for nuclear fuel-containing fuel rods of a nuclear reactor fuel element WO1995024718A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DEP4407711.4 1994-03-08
DE4407711 1994-03-08

Publications (1)

Publication Number Publication Date
WO1995024718A1 true WO1995024718A1 (en) 1995-09-14

Family

ID=6512172

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/DE1995/000214 WO1995024718A1 (en) 1994-03-08 1995-02-20 Spacing grid for nuclear fuel-containing fuel rods of a nuclear reactor fuel element

Country Status (2)

Country Link
TW (1) TW289116B (en)
WO (1) WO1995024718A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2005013286A2 (en) * 2003-07-28 2005-02-10 Framatome Anp Gmbh Fuel element for a compressed water nuclear reactor

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0077709A1 (en) * 1981-10-16 1983-04-27 Commissariat à l'Energie Atomique Spacer grid for a nuclear reactor fuel assembly
EP0088675A1 (en) * 1982-03-04 1983-09-14 Commissariat à l'Energie Atomique Nuclear reactor fuel assembly
GB2238902A (en) * 1989-12-06 1991-06-12 Mitsubishi Nuclear Fuel Grid for nuclear fuel assembly
GB2239124A (en) * 1989-12-06 1991-06-19 Mitsubishi Nuclear Fuel Grid for nuclear fuel assembly
EP0516542A1 (en) * 1991-05-30 1992-12-02 Framatome Thermohydraulic grid and its application in a nuclear fuel assembly

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0077709A1 (en) * 1981-10-16 1983-04-27 Commissariat à l'Energie Atomique Spacer grid for a nuclear reactor fuel assembly
EP0088675A1 (en) * 1982-03-04 1983-09-14 Commissariat à l'Energie Atomique Nuclear reactor fuel assembly
GB2238902A (en) * 1989-12-06 1991-06-12 Mitsubishi Nuclear Fuel Grid for nuclear fuel assembly
GB2239124A (en) * 1989-12-06 1991-06-19 Mitsubishi Nuclear Fuel Grid for nuclear fuel assembly
EP0516542A1 (en) * 1991-05-30 1992-12-02 Framatome Thermohydraulic grid and its application in a nuclear fuel assembly

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2005013286A2 (en) * 2003-07-28 2005-02-10 Framatome Anp Gmbh Fuel element for a compressed water nuclear reactor
WO2005013286A3 (en) * 2003-07-28 2005-06-23 Framatome Anp Gmbh Fuel element for a compressed water nuclear reactor
CN1320553C (en) * 2003-07-28 2007-06-06 法玛通Anp有限公司 Fuel element for a compressed water nuclear reactor

Also Published As

Publication number Publication date
TW289116B (en) 1996-10-21

Similar Documents

Publication Publication Date Title
EP0261544B1 (en) Nuclear reactor fuel element
DE4006264A1 (en) BOILER WATER CORE REACTOR AND CORE REACTOR FUEL ELEMENT FOR THIS BOILER WATER CORE REACTOR
WO1992005564A1 (en) Fuel element for a boiling water reactor with a sealing spring between the foot and the fuel element case
EP0210526B1 (en) Nuclear-fuel assembly
DE1944932B2 (en) SPACER FOR FUEL RODS OF NUCLEAR REACTORS
EP0224728B1 (en) Boiling water nuclear reactor fuel assembly
DE2055339C3 (en) Core grid for a nuclear reactor
EP0184064B1 (en) Nuclear reactor fuel element
DE2233904A1 (en) HOLDING GRID FOR A BUNCH OF CYLINDRICAL ELEMENTS THAT PARTICIPATE IN A HEAT EXCHANGE PROCESS
EP0527244A1 (en) Spacer grid for fuel elements with curved attached springs
EP0285920B1 (en) Nuclear reactor fuel assembly
EP0529128B1 (en) Fuel bundle for nuclear reactor with leaf springs
EP0192092A1 (en) Nuclear-reactor fuel element
EP0307705A1 (en) Nuclear-reactor fuel assembly
WO1995024718A1 (en) Spacing grid for nuclear fuel-containing fuel rods of a nuclear reactor fuel element
DE2941320A1 (en) SPACER FOR FUEL ELEMENTS
DE2755723C2 (en) Tubular heat exchanger
DE9101773U1 (en) Fuel element for a boiling water reactor with a reinforced box
EP0512137B1 (en) Nuclear fuel assembly
EP0750318B1 (en) Spacer grid for nuclear reactor fuel assembly and fuel assembly with such a spacer grid
EP0512132B1 (en) Nuclear pressure water fuel assembly comprising a bottom nozzle with integrated debris catcher
DE19915444A1 (en) Nuclear reactor fuel element has a hexagon-shaped cross-section with fuel rods running vertical to this cross-section and distributed in a triangular pattern
EP0406471B1 (en) Nuclear reactor fuel element
WO1993024933A1 (en) Bundle of nuclear-reactor fuel rods with hexagonal spacers made up of an assembly of basic components
DE19522159C2 (en) Grid-shaped spacer for a nuclear reactor fuel element and a nuclear reactor fuel element

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): JP KR US

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE CH DE DK ES FR GB GR IE IT LU MC NL PT SE

DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
121 Ep: the epo has been informed by wipo that ep was designated in this application
122 Ep: pct application non-entry in european phase