US3726557A - Handling grab - Google Patents

Handling grab Download PDF

Info

Publication number
US3726557A
US3726557A US00155699A US3726557DA US3726557A US 3726557 A US3726557 A US 3726557A US 00155699 A US00155699 A US 00155699A US 3726557D A US3726557D A US 3726557DA US 3726557 A US3726557 A US 3726557A
Authority
US
United States
Prior art keywords
grab
rods
claws
accordance
claw
Prior art date
Legal status (The legal status 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 status listed.)
Expired - Lifetime
Application number
US00155699A
Other languages
English (en)
Inventor
E Ventre
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Electricite de France SA
Original Assignee
Electricite de France SA
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 Electricite de France SA filed Critical Electricite de France SA
Application granted granted Critical
Publication of US3726557A publication Critical patent/US3726557A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • G—PHYSICS
    • G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
    • G21C—NUCLEAR REACTORS
    • G21C19/00—Arrangements for treating, for handling, or for facilitating the handling of, fuel or other materials which are used within the reactor, e.g. within its pressure vessel
    • G21C19/02—Details of handling arrangements
    • G21C19/10—Lifting devices or pulling devices adapted for co-operation with fuel elements or with control elements
    • G21C19/105—Lifting devices or pulling devices adapted for co-operation with fuel elements or with control elements with grasping or spreading coupling elements
    • 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
    • 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
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S294/00—Handling: hand and hoist-line implements
    • Y10S294/906—Atomic fuel handler

Definitions

  • the grab comprises a hollow cylindrical body 'which is connected to a suspension and control unit and in which grappling claws are displaced simultaneously between a position of engagement with a load to be handled and a position of disengagement therefrom.
  • Each claw is supported by two parallel metallic rods which are fastened together along their entire length or only at one end, At least one rod which is of hollow construction, is connected at one end to the exterior and at the other end to a source of control fluid. Said fluid is brought to a temperature which is different from the ambient temperature, thereby causing differential expansion of the two rods and displacement of the claws.
  • This invention relates to a handling grab which is applicable in particular to the handling of fuel elements in a nuclear reactor.
  • grabs which are intended for the purpose of handling different objects are at present in existence. These grabs are usually provided with grappling claws carried by articulated lever-arms whose displacements between inward or outward positions of engagement or disengagement of the load are controlled by mechanical components, electrical components or the like. Said grabs are employed in particular in the case of replenishment of nuclear reactor fuel elements, that is to say in particularly hazardous environments and at high temperatures. In point of fact, whether the control devices are mechanical or electrical, they are easily damaged as a result of the action of nuclear radiations and do not readily withstand the temperatures involved. It is therefore necessary to watch them with very close attention and to replace their control devices at frequent intervals since fault conditions or stoppages of operation can have very serious consequences.
  • the object of the present invention is to overcome this disadvantage by means of a grab in which the control devices are no longer liable to sustain damage, the displacement of the grappling claws being caused by a variation in thermal effect on the devices which support said claws.
  • the handling grab under consideration which comprises a hollow cylindrical body connected to a suspension and control device and in which grappling claws are displaced simultaneously between a position of engagement with a load to be handled and a position of disengagement therefrom is characterized in that each claw is supported by two parallel metallic rods which are fastened together at least at one end thereof, at least one of said rods being of hollow construction and extended internally by means of a passageway which provides a communication with the exterior and being connected to a source of control fluid, said fluid being brought to a temperature which is different from the ambient temperature so as to cause the differential expansion of the two rods and displacement of the claws.
  • the rods are formed of the same metal.
  • the displacements of the grab claws are thus initiated by creating a temperature difference between the metallic rods, that is to say in fact by means of a differential expansion of said two rods.
  • No mechanical or electrical device is used within the interior of the grab, the only means employed being a liquid or gaseous fluid and this latter can be the same as the fluid which constitutes the surrounding atmosphere while being brought to a different temperature, said fluid being circulated through one of the rods while being in contact with the internal wall of this latter.
  • the mechanical strength of a grab of this type is therefore very substantial, irrespective of the ambient temperature and the nature of the fluid which surrounds said grab.
  • FIG. 1 is a longitudinal sectional view of a handling grab in the position of engagement in the left-hand portion and in the position of disengagement in the righthand portion of the figure.
  • FIG. 2 is a bottom view of the grab of FIG. 1.
  • FIG. 3 is a longitudinal sectional view of an alternative form of construction of the grab as also shown in the position of engagement and in the position of disengagement.
  • FIG. 4 is a partial sectional view taken along line II of FIG. 3.
  • the grab which is illustrated in FIG. 1 comprises a hollow cylindrical body 1 which is closed at the top portion thereof by means of an end-piece 2 and this latter is connected to a suspension and control unit (not shown).
  • two grappling claws 4 are suspended from the end-piece 2 by means of two hollow rods 6 and 7 which are parallel to each other and securely fastened together along their entire length although they could be attached to each other only at one of their common extremities. These two rods are formed of the same metal.
  • the rod 6 which is located nearest the grappling tip of the claw 4 is closed at both ends on the one hand by means of the claw itself and on the other hand by means of the end-piece 2 whilst the second rod 7 is extended through the claw 4 by means of a passageway 8 which puts said rod into communication with the exterior and especially with slots 10 which are pierced in the base 12 of the body 1.
  • the two rods 6 and 7 are vertical, that is to say parallel to the lateral wall of the body 1.
  • the claw 4 passes through a slot 14 which is pierced in said well in order to project towards the exterior when said claw is in position for holding a load (not shown).
  • the two rods 6 and 7 are subjected in an identical manner to the temperature of the surrounding fluid irrespective of the nature of this latter and can expand only at the same time and in the same manner. No accidental displacement of the claw 4 need therefore be expected. This latter in any case rests on the edge of the slot 14 in order that the weight of the load should be'carried by the wall of said slot', that is to say by the body 1 itself.
  • each of the internal ducts 7a of the rods 7 has an extension within the endpiece 2 in the form of an elbowed duct 16 and is connected by means of this latter to an axial passage 18 which provides a communication with a fluid source (not shown).
  • a fluid source not shown.
  • a cold fluid is introduced through the passage 18 into the internal duct 7a of the rod 7 up to the moment when said fluid initiates the displacement of the claw 4.
  • the passageway 8 moves away progressively from the slots 10 in order to come into position above the central portion of the base 12.
  • the outlet of the rod 7 is then progressively closed by said base.
  • FIGS. 1 and 2 presupposes that the load to be engaged is pierced by a central bore into which the grab penetrates and is provided with a groove or a shoulder for locking the outwardly-displaced claws.
  • the passage 18 must therefore be supplied with control fluid in order to bring the claws together during introduction of the grab into the load. This supply is then interrupted in order to permit the claws 4 to penetrate into the groove or beneath the shoulder. Handling and displacement of the load can then be carried out in a simple manner without making use of the control fluid and without any danger of accidental disengagement.
  • the shape of the slots 10 can readily be slightly trapezoidal (FIG. 2) in order to ensure progressive closure of the passageway 8 and consequently a complete displacement of the claw.
  • the passageways 8 can be elbowed and open in the direction of the axis of the grab. The discharge of fluid is then prevented progressively by the closing movement of the claws which place the passageways 8 in the line of extension of each other or apply them against a fixed central abutment.
  • FIGS. 3 and 4 show an embodiment of this type in which the grappling members are also maintained in the position of engagement when no control fluid is present but this position of engagement is the position of closure of the claws, the grappling members being directed towards the axis of the grab whilst the lower portion of the body 1 is open.
  • a cooling fluid passes through the rod 7 which is located at the greatest distance from the grappling tip and the two rods have a rectilineal vertical position when no action is produced by the control fluid.
  • the claws are then engaged with the head 22 of the load. Admission of the fluid is intended to initiate the opening movement of the claws, that is to say the displacement of said claws towards the lateral wall of the body 1. Since said body 1 does not have a base, the passageways 8 which form an extension of rod 7 through the claw 1 remain open in the position of disengagement of the claw, deformation of the rods being nevertheless limited by the contact made between the claw and the wall of the body 1.
  • a grab of this type is similar to that of the grab of FIG. 1. In the same manner as this latter, it must be supplied with control fluid while it approaches the load in order to cause the outward displacement of the claws or when it withdraws from the deposited load.
  • the grab is provided with a central projection 20 and when said grab is lowered onto the load to be engaged such as a nuclear reactor fuel element, for example, said projection is abuttingly applied against the head 22 of this assembly. The contact made between these two members then causes the downward movement of the grab to stop and closes off the supply of the duct 18, thereby permitting the inward displacement of the claws as a result of reheating of the rod 7 and return of the rods 6 and 7 to the same temperature.
  • the grab can be displaced with the lpad.
  • the fluid which controls the grappling members is a relatively cold fluid but it is wholly apparent that, if the grab were to be employed for displacing objects placed in an atmosphere at a low temperature, the grab would be capable of operating in the same manner by making use of a relatively hot fluid.
  • This fluid would in that case flow through the rod 6 which is placed in proximity to the grappling tip of the claw and would consequently produce a similar displacement of the claws. The same safety and the same ease of operation would be obtained in this case.
  • Said grab could also be pierced by two series of ducts such as 16 for connecting the rods 6 and 7 respectively to two passages such as 18 which are intended to be connected in one case to a source of hot fluid (supply of the rods 6) and in the other case to a source of cold fluid (supply of the rods 7).
  • the choice of the source and of the control rod is accordingly determined by the intended use of the grab.
  • the rod which is not intended to carry a circulation of fluid need not be closed at both ends but can be solid.
  • the diflerence in temperature between the two rods can also be increased by interposing a heat insulator such as, for example, a layer of metallic wires between said rods and along their entire length in order to ensure thermal decoupling.
  • a heat insulator such as, for example, a layer of metallic wires between said rods and along their entire length in order to ensure thermal decoupling.
  • the two rods can in any case be fastened together only at both ends, thereby permitting deformation of said rods along different curves while nevertheless permitting of sufficient displacement of the claw under the action of differential expansion.
  • the number of the claws can also vary according to the magnitude of the load. Provision is thus made for two claws in FIGS. 1 and 2 and for eight claws in FIGS. 3 and 4.
  • a handling grab comprising a hollow cylindrical body connected to a suspension and control unit and in which grappling claws are displaced simultaneously between a position of engagement with a load to be handled and a position of disengagement therefrom, wherein each claw is supported by two parallel metallic rods which are fastened together at least at one end thereof, at least one of said rods being of hollow construction and extended internally by means of a passageway which provides a communication with the exterior and being connected to a source of control fluid, said fluid being brought to a temperature which is different from the ambient temperature so as to cause differential expansion of the two rods and displacement of the claws.
  • a grab in accordance with claim 1, wherein the hollow body comprises a lateral opening through which the extremity of each claw passes in the position of engagement and a base pierced with slots so as to permit discharge of the control fluid during the greater part of the displacement of the claws towards the position of disengagement.

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Plasma & Fusion (AREA)
  • General Engineering & Computer Science (AREA)
  • High Energy & Nuclear Physics (AREA)
  • Manipulator (AREA)
  • Physical Or Chemical Processes And Apparatus (AREA)
  • Load-Engaging Elements For Cranes (AREA)
  • Filling Or Discharging Of Gas Storage Vessels (AREA)
US00155699A 1970-07-31 1971-06-23 Handling grab Expired - Lifetime US3726557A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
FR7028420*A FR2104696B1 (OSRAM) 1970-07-31 1970-07-31

Publications (1)

Publication Number Publication Date
US3726557A true US3726557A (en) 1973-04-10

Family

ID=9059630

Family Applications (1)

Application Number Title Priority Date Filing Date
US00155699A Expired - Lifetime US3726557A (en) 1970-07-31 1971-06-23 Handling grab

Country Status (3)

Country Link
US (1) US3726557A (OSRAM)
FR (1) FR2104696B1 (OSRAM)
GB (1) GB1311383A (OSRAM)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4351631A (en) * 1979-07-09 1982-09-28 Tpt Machinery Corporation Transfer device for parisons and finished products in injection blow molding devices
US4666198A (en) * 1984-09-06 1987-05-19 Microflex Technology, Inc. Piezoelectric polymer microgripper
US4667997A (en) * 1984-10-31 1987-05-26 Hitachi, Ltd. Grip device
US4713210A (en) * 1985-11-18 1987-12-15 General Electric Company Control rod driveline and grapple
US4858980A (en) * 1988-08-23 1989-08-22 Cincinnati Milacron Inc. Article gripper
US20050135540A1 (en) * 2003-11-17 2005-06-23 Pabis George S. Fuel assembly nozzleless handling tool and method

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0198501B1 (en) * 1985-04-17 1992-07-01 Hitachi, Ltd. Gripping device
US4913617A (en) * 1988-07-20 1990-04-03 Martin Marietta Energy Systems, Inc. Remote tong/tool latch and storage bracket for an advanced servo-manipulator

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3253853A (en) * 1962-12-20 1966-05-31 Alsacienne Atom Electric grab for cartridges

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3253853A (en) * 1962-12-20 1966-05-31 Alsacienne Atom Electric grab for cartridges

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4351631A (en) * 1979-07-09 1982-09-28 Tpt Machinery Corporation Transfer device for parisons and finished products in injection blow molding devices
US4666198A (en) * 1984-09-06 1987-05-19 Microflex Technology, Inc. Piezoelectric polymer microgripper
US4667997A (en) * 1984-10-31 1987-05-26 Hitachi, Ltd. Grip device
US4713210A (en) * 1985-11-18 1987-12-15 General Electric Company Control rod driveline and grapple
US4858980A (en) * 1988-08-23 1989-08-22 Cincinnati Milacron Inc. Article gripper
US20050135540A1 (en) * 2003-11-17 2005-06-23 Pabis George S. Fuel assembly nozzleless handling tool and method
US7239683B2 (en) * 2003-11-17 2007-07-03 Framatome Anp, Inc. Fuel assembly nozzleless handling tool and method
US20080112529A1 (en) * 2003-11-17 2008-05-15 Pabis George S Fuel assembly nozzleless handling tool and method
US7424084B2 (en) 2003-11-17 2008-09-09 Areva Np Inc. Fuel assembly nozzleless handling tool and method

Also Published As

Publication number Publication date
DE2136256A1 (de) 1972-02-03
GB1311383A (en) 1973-03-28
FR2104696B1 (OSRAM) 1973-12-07
FR2104696A1 (OSRAM) 1972-04-21
DE2136256B2 (de) 1975-11-27

Similar Documents

Publication Publication Date Title
US3726557A (en) Handling grab
US3226101A (en) Insulated furnace members
US5459768A (en) Safety device against overpressure failure of a nuclear reactor pressure vessel
KR20190125181A (ko) 물품 반송 장치 및 물품 반송 설비
US4309583A (en) Heat-treating apparatus for prolonging the life of a pressure vessel, especially a reactor pressure vessel
US10026536B2 (en) Holding apparatus, mounting system, and method for holding components during mounting
US3201076A (en) Constant-height vertical support device, in particular for tanks
US3115335A (en) Furnace rolls
US3027611A (en) Stopper rod assemblies
US3252692A (en) Woven heat shields
JPH11109071A (ja) 高速増殖炉およびその炉心上部機構の引抜装置
EP0893510A1 (en) Automatic plant for thermal treatment of metals, in particular steel
CN211040125U (zh) 一种具有防碰撞功能的化工管道补偿器
US3703276A (en) Corrugated inner cover structure
US2278275A (en) Seal for furnace openings
US3301546A (en) Furnace construction
US4707323A (en) Duct closure
CN110056711A (zh) 一种自卸式吊放装置
SU1162731A1 (ru) Устройство дл удержани крупногабаритных изделий при термообработке
US2217384A (en) Protective system for furnace crowns
US2152138A (en) Heat treating equipment
US1481338A (en) Annealing furnace
US3153266A (en) Stopper rod assemblies
JPH0348202Y2 (OSRAM)
US3884624A (en) Nuclear fuel preheating system