摘要:
Le dispositif suivant l'invention concerne les assemblages combustibles pour réacteurs nucléaires tels que ceux refroidis par eau bouillante ou pressurisée. De façon plus précise, ce dispositif concerne les jonctions entre les plaques d'extrémité et des tubes ou tiges de liaison. Le dispositif de jonction comporte au moins une ailette radiale, disposée autour de l'extrémité d'un tube ou tige de liaison. L'extrémité de ce tube ou tige traverse un trou percé dans la plaque d'extrémité et un déplacement angulaire permet d'engager l'ailette dans un logement ménagé dans la paroi de la plaque. Ce dispositif de jonction s'applique à la réalisation d'assemblages combustibles à démontage et remontage faciles au moyen d'outils commandés à distance.
摘要:
The invention relates to a connecting assembly of a centering pin (10) on a core grate (3) of the reactor pressure vessel (1) of a pressurized-water reactor, which centering pin is used to center a fuel element (2), wherein the centering pin (10) is retained in an accommodating bore (16) of a plate (4) present on the core grate (3), with an expanded projection (19) protruding from the accommodating bore (16), in such a way that a form closure is formed. In a pre-assembly state, in which said form closure does not yet exist, the fixing segment (18) is a hollow cylinder, which has, over the entire length of the hollow cylinder, an outer circumferential surface (27) that extends on the lateral surface of a circular cylinder having uniform outside diameter (26). In a final assembly state, the projection (19) is expanded as a consequence of an expansion by means of an expanding tool in such a way that said form closure is formed.
摘要:
The invention relates to a nuclear fuel assembly for a boiling water reactor comprising a base (2), a head, and a bundle of full length fuel rods and partial length fuel rods (11), said bundle extending upwardly and longitudinally from the base (2) to the head, the nuclear fuel assembly (1) comprising at least one clamp (33) for longitudinally retaining a lower plug (13) of a partial length fuel rod (11) with respect to the base (2). The clamp (33) is an additional part fitted to the base (2), the clamp (33) is at least partially received in a housing (30) provided in the base (2), and the clamp (33) is assembled to the base (2) by mechanical engagement of complementary assembly means.
摘要:
The invention relates to a fuel element, for a boiling-water reactor, comprising a water channel (4) and a fuel element base (6), made from a sieve plate (8) and a frame section (7) enclosing the same, whereby the water channel (4) supports a plug (17) with a drilling (16) running therethrough, at the lower end thereof, to which the fuel element base (6) is fixed. The embodiment of the fuel element further comprises an opening (14) through the sieve plate (8), a skirt (19), formed on the underside (18) of the plug (17), surrounding the drilling (16), extending into the opening (14) in the sieve plate (8), a bush (22), provided with a first and a second longitudinal section (23, 24), whereby the first longitudinal section (23) extends from the underside (27) of the sieve plate (8) into the opening (14) in a rotationally-fixed manner and a radial shoulder (25) is provided between both sections (23, 24) which contacts the underside (27) of the sieve plate (8). A threaded section (35) of a screw (34) extends through the bush (22) which engages in a thread in the drilling (16) in the plug (17).
摘要:
A core plate assembly (50) for a nuclear reactor includes a plurality of support beams (60), a flat plate (58) positioned on top of the support beams, a plurality of control rod guide tube openings arranged in staggered rows, and a plurality of fuel supports (98) extending through the flat plate. Each guide tube opening has a cruciform shape which defines four fuel bundle receiving areas. Each fuel support includes a coolant flow inlet (100), and a coolant flow outlet (102) sized to receive a lower tie plate (94) of a fuel bundle (36). The coolant flow inlet is offset from coolant flow outlet so that a centerline (106) of the coolant flow inlet is parallel to a centerline (108) of the coolant flow outlet. The coolant flow inlets are positioned adjacent a support beam, and the coolant flow outlets are positioned in a fuel bundle receiving area.
摘要:
Fuel bundle and control rod assemblies for a nuclear reactor are described. In one embodiment of the apparatus, the nuclear reactor includes several conventional size fuel bundles (162) and at least one large control rod (160). The large control rod (160) includes four fuel bundle receiving channels, and each such channel is sized to receive four conventional size fuel bundles(162).