EP0934218A1

EP0934218A1 - Transportation system and apparatus for remote handling

Info

Publication number: EP0934218A1
Application number: EP97943956A
Authority: EP
Inventors: Graham John British Nuclear Fuels Plc WILSON
Original assignee: British Nuclear Fuels PLC
Current assignee: Sellafield Ltd
Priority date: 1996-09-28
Filing date: 1997-09-26
Publication date: 1999-08-11
Also published as: AU4561597A; GB9620276D0; KR20000048694A; CN1231644A; BR9712137A; JP2001500833A; WO1998013283A1

Abstract

A system and apparatus are described for the transportation of a load within an unmanned area. The apparatus comprises: an elongate conduit following a predetermined desired route in said unmanned area; the interior of the conduit being sealed from the environment in said unmanned area; shuttle means movable within said elongate conduit and having integral on-board drive means to propel said shuttle means along said conduit; slave bogie means outside said elongate conduit, said bogie means being for carrying a payload thereon; said shuttle means having magnetic coupling means to said slave bogie means to move said bogie means substantially coterminously with said shuttle means relative to said elongate conduit; and said shuttle means being accessible from a manned area without the need for decontamination thereof.

Description

TRANSPORTATION SYSTEM AND APPARATUS FOR REMOTE HANDLING

The present invention relates to a system for the remote control of movement of loads within an unmanned area or environment.

It is sometimes necessary to be able to handle and move loads remotely within an unmanned area. Such loads may be hazardous and the environment within the unmanned area may be hostile to human life. However, the environment may not necessarily be hostile but may be unmanned in order to maintain it in a sterile condition such as m the case of handling pharmaceutical materials OJ electronic devices for example.

US-A-4 682 927 describes a clean conveying system wherein light loads of silicon wafers for the manufacture of electronic devices are from one clean room to another via a clean tunnel. The silicon wafers are transported on a driven cart rolling on wheels within the tunnel, the cart being driven by a magnetic coupling from an electric motor and wheel driven cart located outside the clean tunnel. However, only light loads are contemplated and friction of the driven wheeled cart is relatively insignificant.

In the case of handling hazardous materials in the nuclear industry, transportation units or "bogies" employing conventional electric motor drives are freguently used, electrical supplies to the motor being provided by an umbilical cable and reeling mechanisms to pay out and take up slack in the umbilical cable as the bogie moves about. Such transportation devices have the disadvantage that the main drive resides on board the moving bogie and is therefore exposed to contamination within the environment. When failure oi the bogie drive or power supply occurs, subsequent recovery of components for maintenance or repair is very expensive due to decontamination procedures which have to be carried out before human contact. Furthermore, to safeguard the integrity of the interface between the manned and unmanned areas, complicated and expensive flasking arrangements have to be engineered to recover faulty components or to carry out normal maintenance.

The loads needing to be moved in so-called "caves" for the storage of high levei waste, for example, are frequently of the order of 4 to b tonnes and sometimes up to 10 tonnes in weight.

GB-A-958 974 shows a system lor transporting equipment or products in a wheeled bucket moving within a fluid-tight tunnel by means of a magnetic coup! ing external to the tunnel.

US-A-4 392 435 shows a means of transporting material within a closed tunnel by so-called linear motor drives. This prior art also describes levi ation and machining of radioactive fuel rod material within the tunnel.

The above references essentially describe the containment of "sterile" or hazardous materials within a closed, fluid-tight tunnel passing through or existing within an area manned by people.

It is an object of the present invention to provide apparatus for a transportation system lor hazardous materials, for example, within an unmanned area wherein a transport module such as a bogie has a minimum number of active components which may fail or need frequent maintenance within the unmanned area.

According to the present invention, there is provided apparatus for a transportation system for the movement of a hazardous load within an unmanned area, the apparatus comprising: an elongate conduit following a predetermined desired route in said unmanned area; the interior of the conduit being sealed from the environment in said unmanned area; shuttle means movable within said elongate conduit and having integral on-board drive means to propel said shuttle means along said conduit; slave bogie means outside said elongate conduit, said bogie means being for carrying a payload thereon; said shuttle means having magnetic coupling means to said slave bogie means to move said bogie means substantially coterminously with said shuttle means relative to said elongate conduit; and said shuttle means being accessible from a manned area without the need for decontamination thereof.

The unmanned area may, for example, be so-called "cave" for the storage of high level radioactive waste stored and grouted into large and heavy stainless steel drums weighing up to about 10 tonnes in some cases for example and which need to be moved within the cave from time to

The shuttle means may be accessible at one or both ends of the conduit for repair or maintenance, or at positions intermediate the conduit ends.

The manned and unmanned areas may be separated by a suitable interface such as a wall having the appropriate protection characteristics. The end of the conduit may breach the interface so as to be easily accessible from the manned area. Where the unmanned area is used for the storage of radioactive materials, any necessary radiological shielding of the area where the shuttle is accessed will of course be employed. However, the interior of the conduit will be sealed from the environment within the unmanned area at least in the case where the environment is hazardous to people.

The environments of the manned and unmanned areas may be mutually sealed from each other as described above where toxic or otherwise hazardous materials are being handled or may merely exclude the presence of human or living organisms. In the latter case such as with pharmaceutical materials or a "clean" assembly area for example, the unmanned area may have a positive atmosphere pressure to cause a net outflow of air to an adjacent manned area for example .

The unmanned area may have a conventional horizontal floor of concrete or metal for example on which the bogie may move, such as on wheels on the floor or on flanged wheels on rails on the floor for example. However, the bogie is not limited to moving on supporting wheels as will be explained in greater detail below. The conduit may be a tube having any desired cross-sectional shape such as round, rectangular, oval or diamond for example. However, a round and rectangular sections are in many cases preferred since these are more easily dealt with by forming into curves for example.

The conduit may be supported on or above the floor of the unmanned area; embedded within the floor; suspended below a sheet metal floor; or, suspended from a ceiling for example .

However the conduit is positioned or orientated, it is at least desirable that the interior volume of the conduit is not accessible to the environment within the unmanned area as this could provide a path for contamination to the manned area or vice versa. In cases where the environment of the unmanned area is hostile, It is essential that the interior of the conduit is not accessible thereto.

However, where the conduit is sited below a metal floor in an otherwise safe area for example, it may be acceptable for the conduit to have a slot, for example, running along at least a part of the longitudinal length thereof so to provide for access to the shuttle for electrical supplies for example. In such installations, the metal floor may constitute the means by which the conduit interior is sealed or separated from the environment within the unmanned area. Such considerations will be explained in more detail below.

The material of the conduit is desirably non-magnetic such as stainless steel for example.

The conduit will follow predetermined desired routes or paths through the unmanned area and may also have junctions where two or more conduits are joined so as to be able to change the direction of movement of a particular bogie.

Essentially, the shuttle comprises a dynamic component of the apparatus and system, providing drive means to the bogie which is a passive device moving under the influence of the shuttle. The means of moving the shuttle within the conduit may be any that, are appropriate to the requirements of the apparatus in question. In one embodiment, the shuttle may, for example, have an on^¬ board electric motor/gearbox drive to wheels engaging with the inner surface of the conduit to provide movement .

In another embodiment, the shuttle may have a linear motor to provide levitation and/or translation along the conduit, passive guidance wheels or sliders being provided to engage the interior of the conduit.

In yet another embodiment, the shuttle may be suspended within the conduit by attractive magnetic forces generated by electromagnets in a similar manner to the suspension of a rotatable shaft suspended by so-called magnetic bearings; and employing similar control systems to maintain the shuttle in a desired position WLthin the conduit or alternatively, passive slave rollers or sliders being utilised to keep the shuttle in a required position. Translation along the conduit may be effected by conventional electric motor/gearbox/wheel drives or by linear motor means.

In cases where translation of the shuttle along the conduit is provided by linear motor drive means, an aluminium reaction plate may be fixed to or otherwise associated with the conduit.

Electrical power supplies and/or control signals to the shuttle may be provided by an umbilical cable and associated reeling equipment tor example or may alternatively be supplied by bus-bars/electric rails positioned within the conduit and with which suitable contact means on the shuttle engage.

The conduit may be constructed in modular form, having substantially identical portions which are joined together to form an extended elongate length as desired. Alternatively, a portion forming a node or a junction where two or more conduits are joined may also be provided in modular form having common joining arrangements to single linear or curved sections. Such modular sections may also include electrical supply provisions such as bus-bars for example. Where necessary, jointing arrangements may also include associated sealing means so as to maintain the integrity of the conduit interior from the unmanned area.

The bogie may be supported by and run on conventional wheels on rails for example for guidance. However, the bogie may be suspended by electromagnetic levitation means. In the former case, i.e. wheeled support for example, where there is a relatively high friction component incumbent in moving the bogie, the coupling force needs a correspondingly relatively high lateral component to move the bogie by the shuttle. Thus, linear motor drive and coupling means are preferred. In the latter case where electromagnetic suspension or levitation of the bogie is effected, a correspondingly relatively lower lateral force component is required to move the bogie since there is substantially no friction but only inertia to overcome. Thus, coupling by the electromagnetic suspension or levitation means as distinct from linear motor means may be sufficient. As a general rule, the lateral force generated by electromagnetic attraction is about 10% of the attractive force. A further reason for preferring suspension or levitation of the bogie is that the resulting frictionless air gap allows the bogie to ride over any debris which may have fallen on guidance rails and which may be used with a wheel supported bogie. Thus, in addition to the rolling frictional resistance from the wheel bearings and wheel and rail contact, there is also the time dependent increase due to debris build up on the rails from the waste being moved around the unmanned area .

The bogie is movably linked to the shuttle by magnetic means such that movement of the shuttle induces corresponding movement of the bogie. Such magnetic means may, however, comprise alternative devices in practice. For example, the bogie may be linked to the shuttle by linear motor means, the bogie having a reaction plate and the shuttle the necessary coil windings of the linear motor couple. The bogie may move by being levitated by the linear motor coterminously with the shuttle movement. Various additional guidance means may also be provided such as passive wheels or riders or sliders or jockey wheels tor example so as to mechanically gui e or maintain the bogie in a preferred position, attitude o ori entati o .

The bogie may alternatively be movably coupled to the shuttle by magnetic forces generated by electromagnets carried by the shuttle for example reacting with permanent magnets or iron reaction cores on the bogie. Mechanical guidance means including wheels co-operating with rails for example such as described above may be incorporated on the bogie. Tn a further alternative embodiment, the bogie may be suspended about the conduit by attractive magnetic forces. The shuttle may incorporate electromagnets disposed about its body so as to levitate the bogie, control being provided as before by similar control systems to those employed in magnetic bearings for the suspension of a rotatable shaft for example.

The system and apparatus according to the present invention may employ any combination of technically compatible means in the alternative bogie, shuttle and conduit constructions described above.

A major advantage of the present invention is that only the bogie is exposed to any hostile environment within the unmanned area and which comprises a minimum of moving parts in most embodiments and in some embodiments no moving parts other than the movable shuttle unit per se. Therefore, reliability is improved and cost lowered due to fewer breakdowns and lower maintenance requirements. However, even if reliability of the shuttle per se were to be the same as before, the availability of the transport and handling system would nevertheless be greatly improved since no decontamination procedures for the shuttle are necessary and it is much more readily accessible for maintenance and/or repair. Safety is also greatly enhanced since human contact with contaminated components is reduced compared with prior art systems and apparatus. In particular, the apparatus of the present invention eliminates unreliable umbilical cable and reeling devices from the unmanned area. The handling and positioning of loads onto and removing loads from the bogies may be effected by cranes and/or manipulators sited within the unmanned area and controlled remotely therefrom.

In order that the present invention may be more fully understood, examples will now be described by way of illustration only with reference to the accompanying drawings, of which:

Figure 1 shows a schematic arrangement showing the major components of the apparatus and system of the present invention and their relative dispositions;

Figure 2 shows a selection of alternative cross-sectional shapes of conduits;

Figures 3A and 3B show a schematic cross-sectional end view and a part-sectioned side view, respectively, of a first embodiment of apparatus according to the present i nvention;

Figure 4 shows a schematic cross-sectional end view of a second embodiment;

Figure 5 shows a similar view to Figure 4 of a third embodiment;

Figure 6 shows a schematic end view of a fourth embodiment of apparatus according to the present invention;

Figure 7 shows a plan view ot the apparatus of Figure b on the line 7-7 of Figure 6; Figure 8 shows a similar view to that of Figure 6 of a fifth embodiment;

figure 9 shows a schematic plan view of drive arrangements of the shuttle and bogie of Figure 8;

Figure 10 shows a section of conduit and part of a bogie drive shuttle of a sixth embodiment of apparatus according to the present invention;

Figure 11 shows a radial cross section through apparatus of the sixth embodiment;

Figure 12 shows an elevation of bogie levitating means associated with the shuttle shown in Figure 10;

Figure 13 shows a plan view of the bogie levitating means of Figure 12 along the line 13-13;

Figure 14 shows a detail of an electromagnet arrangement used m the bogie levitating means of the sixth embodiment; and

E'igure 15 which shows a cruciform arrangement of levitating magnets of a shuttle of Figures 10 to 14.

In the drawings, similar features will be denoted where appropriate by common reference numerals.

Referring now to Figure 1 and where a generalised schematic view of a system and apparatus according to the present invention is indicated generally at 10. An unmanned area is indicated at 12 and a manned area at 14, the two areas being separated by an interface, in this case a wall 16. A conduit 18 is provided, the interior 20 of which being accessible from the manned area 14 but not from the unmanned area 12. Inside the conduit 18 is a movable shuttle 22 which moves as a result of power and control signals supplied through an umbilical cable 24 (it. should be born in mind that other means of providing power and control signals may alternatively be employed as will be described herembelow) , the cable 24 having a reeling device 26 at one end thereof. The cable 24 and reeling device 26 are within and accessible from the manned area 14. The shuttle 22 has means to both move it through the conduit 18 under control and magnetic means to cause a bogie 28 to follow the shuttle and which will be described below in greater detail with respect to the various embodiments. The bogie moves within the environment of the unmanned area 12 to carry a load indicated generally at 30.

Figure 2 shows examples of alternative cross-sectional shapes of conduits which may be employed.

A first embodiment of the present invention is shown in Figures 3A and 3B . In this embodiment, the shuttle 22 comprises a body levitated and driven in translation through the conduit 18 by linear motors. Coils 60 (only one shown) for levitation of the shuttle are placed at each end of the shuttle and a coil 62 for translations, movement is also provided (although coils 60 also provide translation) together with an aluminium reactor plate 64 fixed to the lower side of the conduit 18. The shuttle also carries an electromagnet 66 producing a magnetic flux 68 which links with an iron core 70 in the bogie 28 for translation of the bogie. The bogie 28 is supported by linear motor coils 74 in the shuttle which cooperate with an aluminium reactor plate 76 in the bogie (linear motors 74 may alternatively provide translation in place of electromagnet 66). Passive guidance wheels 78 are provided on the shuttle. The guidance wheels 78 may cooperate with features such as grooves, rails or flanges (not shown) on the inner surface of the conduit to prevent unwanted rotation of the shuttle about its axis. Although the bogie 28 is levitated and supported by the linear motors 74, additional guidance means such as wheels or sliders (not shown) for example contacting adjacent rails (not shown) for example may also be employed to prevent rotation or instability of the bogie about its longitudinal axis. Movement of the bogie is by virtue of the magnetic linkage between the electromagnet 66 on the shuttle and the iron core 70 on the bogie.

Figure 4 shows a second embodiment wherein the shuttle 22 is supported out of contact with the conduit 18 by magnetic fluxes provided by electromagnets 100, 102 between the shuttle and iron core 104, 106 fixed to the lower side of the conduit 18 and to the underside of the bogie, respectively. Two or more sets of the electromagnets 100, 102 may be provided along the axial length of the shuttle body. The air gaps indicated at "A" and "B" may be controlled dynamically according to size by varying the flux density by a suitable control system indicated only schematically at 110, signals for which are supplied along an umbilical cable (not shown) for example. A suitable control system may be based on those known in the art for the suspension of rotatable shafts in what are commonly known as magnetic bearings. Support of the bogie and translation of the shuttle and bogie may be by any appropriate means such as a linear motor for example as described with respect to earlier embodiments.

Figure 5 shows a third embodiment wherein the conduit 18 has an oval-shaped cross section and levitation of both the shuttle and the bogie is effected by magnetic flux attraction generated by electromagnets. A magnetic flux generated by an electromagnet 120 in the shuttle 22 links with an iron core 122 fixed to an upper planar portion 124 of the conduit 18 and is attracted thereto thus levitating the shuttle. Two further electromagnets 126, 128 attract the bogie 28 in an upwardly direction by virtue of iron core 130, ] 32 let into skirt portions 134, 136 of the bogie. The conduit 18 is supported above the floor 138 of the unmanned area 12 by pillars 140 spaced- apart along the length of the conduit. The iron reaction core 130, 132 of the bogie partially encircle the conduit so as to be able to produce a net resultant force in an inwardly and upwardly direction relative to the bogie and the shuttle 22. As with previously described embodiments, control systems such as those employed for so-called magnetic bearings may be utilised to control the distances between the shuttle, conduit and bogie by varying the magnetic flux density.

Figures 6 and 7 show a fourth embodiment 150 of apparatus according to the present invention. The apparatus comprises a rectangular conduit 152 fabricated from stainless steel sheet; a shuttle 154 movable with the conduit 152; and, a bogie 156 movable about and along the conduit substantially coterminously with the shuttle. The plan view of Figure 7 is greatly simplified with the omission of much detail in the interests of clarity. The conduit 152 is supported above the floor 158 by pillars 160. The shuttle 154 comprises a linear motor 162 guided by flanged wheels 164 on rails 166 and having a reaction plate 168 fixed to the base of the conduit 152. Carried by the wheeled linear motor drive unit are four electromagnets 170 rigidly supported in cantilever fashion by upper and lower support arms 172, 174 respectively. The bogie 156 is arranged around the conduit 152 and comprises an upper platform 176, side arms 178 depending vertically from the upper platform 176 and short horizontal arms 180 having return poles 182 for the electromagnets 170 extending underneath a portion of the conduit 152 so that the return poles 182 are vertically coincident with the electromagnets 170. Reinforcement brackets 184, 186 are provided to increase rigidity. The length of the conduit may be somewhat greater than the overall length of the shuttle but not so that stability thereof is impaired due to a heavy load 190 placed on the platform 176. Bus bars 192 on the inside of the conduit supply power and control signals to the bogie via pick-ups 194 thereon. The conduit 152 is modular in construction with units being adapted to be joined together to form an extended length and following a desired route through a "cave" 196 for the storage of radioactive waste for example. Directional changes by means of gentle curves may be made in the conduit. At rest, the lower faces of the short arms 180 sit on the floor 158 when the electromagnets are inoperative. In operation, the electromagnets 170 are energised to attract the poles 182 thus raising the bogie from the ground and suspending it in controlled fashion by means of a feedback loop control system shown only schematically at 198, the system having proximity sensors 200, 202 to enable control signals to maintain a predetermined clearance air gap 204 between the upper face 206 of the pole piece 182 and the lower face 208 of the conduit 152. Since the bogie 156 and load 190 are suspended in air, there is substantially no frictional component to moving the bogie and the horizontal force component generated by the electromagnets 170 is sufficient to move the bogie and load substantially coterminously. In addition to the proximity sensors 200, 202 controlling the vertical air gap 204, there are further sensors 210, 212 to enable the acceleration and deceleration of the shuttle to be controlled at such rates that the bogie remains in a substantially constant position above and relative to the shuttle, i.e. the horizontal component of the magnetic field of the electromagnets 170 is not exceeded by the inertia of accelerating and slowing the bogie and load. Lateral positional control of the bogie relative to the conduit is effected by four further electromagnets 21 (only one shown in Fi g .7 ) mounted on the shuttle and return pole pieces 218 (only one shown in Fig.7) mounted on the bogie. Sensors 220, 222 in a feed-back loop to the control system 198 maintain a substantially constant air gap 224 between the bogie and conduit.

Figures 8 and 9 show schematic end and plan views oi a fifth embodiment 300 of apparatus according to the present invention. In this embodiment the apparatus comprises a conduit 302 containing a shuttle 304 and having a bogie 306 around the conduit and above the shuttle. In this embodiment, the shuttle 304 has a linear drive motor 308 running on flanged guidance wheels 310 on rails 312 and driving via a reaction plate 314 fixed to the interior surface of the conduit 302. The conduit is mounted on pillars 316 to allow access to the underneath ol the laterally outer portions of the conduit. Mounted on a support structure 320 on the shuttle 304 are linear motor drive units 322. The bogie 306 has an upper platform 324 to accept a load 326, side arms 328 depending vertically from the upper platform 324 and short laterally directed arms 330 extending underneath the laterally outer portions of the conduit and having linear motor reaction units 332 fixed thereto. However, in this embodiment, the bogie 306 is not suspended with an air gap but supported on flanged wheels 334 running on guidance rails 336 on the floor 338. The increased friction created by the wheels and axles on the rails and the gradual increase in operational friction due to debris falling on the rails necessitates a more powerful driving force which is provided by the linear drive motors 322, 332 to the bogie. This embodiment enables a somewhat simpler control system to be utilised, however, sensors 340, 342 to make sure the bogie remains and moves substantially coterminously with the shuttle are employed. In this embodiment, the linear motors driving the bogie may be reversed during braking to slow down the bogi e .

Ln the above embodiment two linear drive motors to the bogie are used and one linear drive motor to drive the shuttle relative to the conduit. However, in the above embodiment, and also in the embodiment described with reference to Figures 6 and 7 the shuttle linear motor drive means 168, 308 may be replaced with a more conventional on-board motor driving the shuttle through a gearbox and driven wheels for example.

Figures 10 to 15 inclusive show various views of a sixth embodiment 400 of apparatus according to the present invention as will be described below. The apparatus comprises a cylindrical conduit. 402 supported on pillars 404, a shuttle 406 therein and a bogie 408 disposed around the conduit as shown in Figure 11. The shuttle comprises a central drive car 410 having a linear motor drive 412 driving via a reaction plate 414 fixed within the conduit, the drive car 410 running on guidance wheels 416 on the reaction plate which prevents rotation of the shuttle within the conduit; and, electromagnetic suspension units 420, 422 situated at the front and rear of the drive car 410 respectively (Figure 10 shows only the drive car 410 in the conduit. 402 whilst Figure 12 shows the levitation units 420, 422 which in fact have the drive car 410 interposed therebetween) . The suspension units 420, 422 are substantially identical in construction and function and each comprise four electromagnets 424 in cruciform arrangement (shown more clearly in Figs 14 and 15 which show two and four magnets respectively) . Each electromagnet 424 also includes a frame 426, part of which 428 is triangular in section and also constitutes the bridge part, of the U-shaped e Lectromagnet pole piece, the triangular 428 section allowing the four electromagnets to nestle together separated by spacers 430 as is shown more clearly in Figures 14 and 15. The coil windings tor the electromagnets 424 are denoted by reference numeral 432. The frames 426 also include spacer jockey wheels 436 rotating on axLes 438 to maintain the curved electromagnet pole piece faces 440 a predetermined distance from the interior surface of the cylindrical conduit 402. Straps 444 are provided to connect the front 420 and rear 422 suspension units to the central drive car 410. A control system indicated generally at 450 is provided in the drive car 410 to apportion power to the electromagnets 424 for suspending the bogie 408. The bogie 408 includes an upper platform 460 to receive a load 462 and a rigid framework comprising vertically depending arms 464 and short horizontally directed arms 466, the arms being braced for purpose of rigidity by cross pieces 468. The cross pieces 468 also have fixed thereto electromagnet return pole pieces 470 in substantially radial alignment with the faces 440 of the electromagnets 424. The short horizontally directed arms 466 are provided with low friction slider plates 472 co- operating with the pillars 404 to maintain the required radial orientation of the bogie with respect to the shuttle and conduit. However,- the slider plates may be replaced with jockey wheels or electromagnets for example to maintain a constant gap and consequently the desired orientation of the bogie. Power to the linear drive motor 412 and to the control system 450 is supplied via bus bars 476 running along the inside of the conduit to pickups (not shown) on the drive car 410. Control of the electromagnets 424 may be by a known type of control system used for the suspension of a shaft by so-called magnetic bearings. The bogie is suspended by the magnetic fields produced by the electromagnets 424 so as to produce a substantially constant air gap for frictionless movement of the bogie substantially coterminously with the shuttle.

Sensor and control systems of the type described with respect to the embodiment shown in Figures 6 and 7 may be employed in the sixth embodiment. The horizontal component of the magnetic fields produced by the electromagnets 424 are sufficient to move the bogie with a heavy load. However, the bogie may alternatively be suspended by the electromagnets as described above but translation with the shuttle may be effected by means of separate linear motors and reaction units on the shuttle and bogie. The same may apply to the embodiment shown in Figures 6 and 7.

It will be realised from the above examples which, are not intended to be limiting, that the bogie which is the only component of the system and apparatus of the present invention, other than the outer surface of the conduit, which is exposed to the environment within the unmanned area. The bogie essentially contains few or no moving parts which are likely to fail unexpectedly or which require frequent maintenance.

Claims

1. A transportation system for the movement of a hazardous load within an unmanned area, the apparatus comprising: an elongate conduit following a predetermined desired route in said unmanned area; the interior of the conduit being sealed from the environment in said unmanned area; shuttle means movable within said elongate conduit and having integral on-board drive means to propel said shuttle means along said conduit; slave bogie means outside said elongate conduit, said bogie means being for carrying a payload thereon; said shuttle means having magnetic coupling means to said slave bogie means to move said bogie means substantially coterminously with said shuttle means relative to said elongate conduit; and said shuttle means being accessible from a manned area without the need for decontamination thereof.

2. Apparatus as in claim 1 wherein the environments of the manned and unmanned areas are mutually sealed from each other.

3. Apparatus as in either claim 1 or claim 2 wherein the conduit is a tube having a cross-sectional shape selected from round, rectangular, oval or diamond.

4. Apparatus as in any one preceding claim wherein the conduit is supported on or above the floor of the unmanned area; embedded within the floor; or, suspended below a floor.

5. Apparatus as in any one preceding claim wherein the interior volume of the conduit is not accessible to the environment within the unmanned area.

6. Apparatus as in any one preceding claim wherein the material of the conduit is non-magnetic.

7. Apparatus as in any one preceding claim wherein two or more conduits are joined so as to be able to change the direction of movement of a bogie.

8. Apparatus as in any one preceding claim wherein the shuttle has an on-board electric motor/gearbox drive to wheels engaging with an inner surface of the conduit to provide movement.

9. Apparatus as in any one preceding claim from 1 to 7 wherein the shuttle has a linear motor to provide levitatio .

10. Apparatus as in any one preceding claim from 1 to 7 and 9 wherein the shuttle has a linear motor to provide translation along the conduit.

11. Apparatus as in any one preceding claim from 1 to 8 and 10 wherein said shuttle is suspended within the conduit by attractive magnetic forces generated by electromagnets .

12. Apparatus as in any one preceding claim wherein electrical supplies to the shuttle are provided by an umbilical cable.

13. Apparatus as in any one preceding claim from 1 to 11 wherein electrical supplies to the shuttle are provided by bus-bars in said conduit.

14. Apparatus as in any one preceding claim wherein the conduit is constructed in modular form having substantially identical portions joined together to form an extended elongate length.

15. Apparatus as in any one preceding claim wherein the shuttle is linked to the bogie by linear motor means.

16. Apparatus as in any one preceding claim from 1 to 1 wherein the bogie is movably coupled to the shuttle by magnetic forces generated by electromagnets carried by the shuttle.

17. Apparatus as in any one preceding claim wherein the bogie is suspended about the conduit by attractive magnetic forces generated by electromagnets disposed in the shuttle.

18. Apparatus according to claim 17 wherein the bogie s movably coupled to the shuttle by magnetic forces generated by electromagnets.

19. Apparatus according to any one preceding claim wherein the bogie is mounted on wheels.

20. Apparatus according to claim 19 wherein the bogie is coupled to the shuttle by linear motor drive means.

21. Apparatus substantially as hereinbefore described with reference to the accompanying description and Fig.l; r Fig.2; or Fig.3; or Fig.4; or Fig.5; or Figs. 6 and ; or Figs. 8 and 9; or Figs.10 to 15 of the drawings.