Abstract: Various example embodiments are directed towards an improved control drum, as well as systems, apparatuses, and/or methods for operating a nuclear reactor with a plurality of improved control drums. The control drum includes an outer shell, an inner shell, a plurality of tubes, the plurality of tubes including at least one neutron absorbing tube and at least one neutron scattering tube, and at least one baffle plate arranged between the outer shell and the inner shell, the at least one baffle plate including a plurality of perforations, and at least one perforation of the plurality of perforations configured to support a tube of the plurality of tubes.

Abstract: An underground nuclear power reactor having a hollow blast tunnel which extends from one end of a containment member which houses a nuclear reactor, heat exchanger, generator, etc. A hollow blast tunnel extends from one end of the containment member with a normally closed door positioned therebetween. The blast tunnel defines a blast chamber having a plurality of spaced-apart debris deflectors positioned therein. The blast chamber has an upper wall with a roof opening formed therein which is selectively closed by a roof portion. If the reactor needs to be repaired or replaced, the door is opened so that the reactor will pass therethrough into the blast chamber and outwardly through the roof opening. If the reactor explodes, the blast therefrom drives the debris therefrom through the door and into the blast chamber where the deflectors reduce the blast force as the debris passes through the blast chamber.

Abstract: A nuclear reactor module includes a reactor core and a reactor housing that surrounds the reactor core about its sides, wherein the reactor housing is configured to direct coolant through the reactor core. A neutron reflector is located between the reactor core and the reactor housing, wherein the neutron reflector has a plurality of inlet ports facing the reactor core. The neutron reflector also has a plurality of outlet ports fluidly connected to the inlet ports to direct a portion of the coolant through the neutron reflector.

Abstract: A method for producing uniform activity targets according to an embodiment of the invention may include arranging a plurality of targets in a holding device having an array of compartments, each target being assigned to a compartment based on a known flux of a reactor core so as to facilitate an appropriate exposure of the targets to the flux based on target placement within the array of compartments. The holding device may be positioned within the reactor core to irradiate the targets. The method may be used to produce brachytherapy and/or radiography targets (e.g., seeds, wafers) in a reactor core such that the targets have relatively uniform activity.

Abstract: There is provided a holding device which can hold a molten corium for a predetermined period even when the molten corium is exposed to heat or undergoes any chemical reaction and which is applicable to practical use. There is provided a holding device provided below a nuclear reactor pressure vessel for holding a molten corium, wherein the holding device includes a base material in contact with a cooling medium, and a multilayer stack structure on the base material. The multilayer stack structure has a first layer having heat-resistant property, a second layer formed on the first layer and having heat-resistant property with lower heat conductivity than that of the first layer, and a third layer formed on the second layer and having corrosion-resistant property and impact-absorbing property.

Abstract: Internal head vents are usable in nuclear reactors and include piping inside of the reactor pressure vessel with a vent in the reactor upper head. Piping extends downward from the upper head and passes outside of the reactor to permit the gas to escape or be forcibly vented outside of the reactor without external piping on the upper head. The piping may include upper and lowers section that removably mate where the upper head joins to the reactor pressure vessel. The removable mating may include a compressible bellows and corresponding funnel. The piping is fabricated of nuclear-reactor-safe materials, including carbon steel, stainless steel, and/or a Ni—Cr—Fe alloy. Methods install an internal head vent in a nuclear reactor by securing piping to an internal surface of an upper head of the nuclear reactor and/or securing piping to an internal surface of a reactor pressure vessel.

Abstract: A nuclear reactor includes a pressure vessel and a nuclear reactor core disposed in the pressure vessel. A subterranean containment structure contains the nuclear reactor. An ultimate heat sink (UHS) pool is disposed at grade level, and an upper portion of the subterranean containment structure defines at least a portion of the bottom of the UHS pool. In some embodiments, the upper portion of the subterranean containment structure comprises an upper dome, which may protrude above the surface of the UHS pool to define an island surrounded by the UHS pool. In some embodiments, a condenser comprising a heat exchanger including hot and cold flow paths is disposed inside the subterranean containment structure; and cooling water lines operatively connect the condenser with the UHS pool.

Abstract: Heat from an ex-vessel mass of core material is removed to cooler regions of a containment envelope via liquid and/or vapor phase transport. Various aspects provide for contacting the ex-vessel core material with a material having properties including melting point, boiling point, and condensation kinetics such that condensation of the material in cooler regions of the containment envelope is at least as fast as evaporation of the material due to heat absorption from the core material and associated species.

Abstract: A head module for a large-scale container, a large-scale container having the head module, and methods for manufacturing the head module and the large-scale container. The method for manufacturing a head module comprises providing a head having an annular opening, the head being composed of a plurality of petals, providing a plurality of cylinder plates, and forming a head cylindrical ring, connecting in order the plurality of cylinder plates to the end surface of the annular opening and joining facing sides of all adjacent cylinder plates. Based on the unfitness of the petals at the annular opening of the head, gaps between adjacent cylinder plates may be adjusted, and/or the positions of the cylinder plates on the end surface of the annular opening of the head may be adjusted radially inwards or outwards.

Abstract: An integrated reactor missile shield and crane assembly (IRMSCA) is disclosed and claimed. The IRMSCA replaces the existing concrete missile shields and reactor services crane. The IRMSCA is moveable such that the missile shield can be moved away from the reactor head, allowing the integral crane to lift the control rod drive mechanism components and other routine loads at the refueling cavity.

Abstract: An apparatus is provided and includes a reactor core, a boom and a shield assembly supportively interposed between the reactor core and the boom, a heat pipe disposed in thermal communication with the reactor core, a thermoelectric power converter operably coupled to the heat pipe, struts supportively coupled to the heat pipe at opposite ends of the power converter and hinge joints to rotatably couple the struts to the boom, at least one of the hinge joints being spring-loaded.

Abstract: In a nuclear reactor building of a steel plate concrete structure that houses a pressure containment vessel formed with a plurality of penetration ports penetrating the pressure containment vessel on the periphery thereof and includes a biological shielding wall disposed outside the pressure containment vessel. The pressure containment vessel is vertically divided into a plurality of blocks so that each of the blocks has one or more pressure containment vessel penetration ports arranged on a same horizontal plane, and the reactor building including the biological shielding wall is divided into a plurality of modules by the horizontal plane.

Abstract: The present invention provides a method of manufacturing a core shroud for a nuclear plant and a nuclear power plant structure in which a groove portion is easily assembled in the case of manufacturing the core shroud having a weld structure of a nuclear power plant by a laser welding, and it is possible to obtain a weld joint portion in which a plastic distortion region and a residual stress are as small as possible, going with a solidification shrinkage of the weld portion. At a time of welding butted portions of a plurality of members constructing a core shroud, a root face is provided in the butted portion, a length of the root face is set to 25% to 95% of a thickness of the thinner one of the butted portions of a plurality of members, a narrow groove is provided in the other than the root face, and the butted portions are welded by a laser welding using a weld wire.

Abstract: A neutron absorbing insert for use in a fuel rack and method of manufacturing the same. In ones aspect, the invention is a neutron absorbing apparatus comprising: a plate structure having a first wall and a second wall that is non-coplanar to the first wall; the first and second walls being formed by a single panel of a metal matrix composite having neutron absorbing particulate reinforcement that is bent into the non-coplanar arrangement along a crease; and a plurality of spaced-apart holes formed into the single panel along the crease prior to bending.

Abstract: Disclosed herein is a fully passive decay heat removal system utilizing a partially immersed heat exchanger, the system comprising: a hot pool; an intermediate heat exchanger which heat-exchanges with the sodium of the hot pool; a cold pool; a support barrel extending vertically through the boundary between the hot pool and the cold pool; a sodium-sodium decay heat exchanger received in the support barrel; a sodium-air heat exchanger provided at a position higher than the sodium-sodium decay heat exchanger; an intermediate sodium loop connecting the sodium-sodium decay heat exchanger with the sodium-air heat exchanger; and a primary pump, wherein a portion of the effective heat transfer tube of the sodium-sodium decay heat exchanger is immersed in the cold pool, particularly in a normal operating state, and the surface of the lower end of a shroud for the sodium-sodium decay heat exchanger, the lower end being immersed in the sodium of the cold pool, has perforated holes.

Abstract: A method of using automatic whole body personnel contamination monitors and/or means for decontaminating individuals exposed to radioactive material contamination is provided. The inventive method involves the use of these monitors and/or decontamination means in intermodal containers of mobile-unit structures dedicated to responding to radiological emergency situations. Also provided are such mobile-unit structures, as well as systems that employ such mobile-unit structures.

Abstract: A system includes a containment vessel configured to prohibit a release of a coolant, and a reactor vessel mounted inside the containment vessel. An outer surface of the reactor vessel is exposed to below atmospheric pressure, wherein substantially all gases are evacuated from within the containment vessel.

Abstract: A neutron reactor includes a neutron shield which is disposed outside a nuclear reactor core and adapted to absorb neutrons leaking from the core. The neutron shield includes a plurality of containers each of which contains a powdered neutron absorbing material and which are stacked with one another in a vertical direction, and a cladding tube which houses the containers. The neutron absorbing material is composed of B4C powder.

Abstract: A pressurized water reactor nuclear containment radiation shield which surrounds the upper portion of a pressure vessel in an ice condenser containment. The vertical walls of the neutron shield are formed in vertical sections with the lower and upper sections operable during outages, to open to promote air flow cooling along the walls in the vicinity of the vessel head.

Abstract: A method for carrying out a reactor internal, comprising steps of: forming a first opening portion in a ceiling of a reactor building at a position directly above an equipment pool in said reactor building; cutting a cylindrical reactor internal surrounding a core in a reactor pressure vessel disposed in said reactor building, at one position in an axial direction; surrounding said cut cylindrical reactor internal with a radiation shield; and carrying out said cylindrical reactor internal surrounded by said radiation shield out of said reactor building through said first opening portion.

Abstract: The reactor vessel of a nuclear reactor installation which is suspended from the cold leg nozzles in a reactor cavity is provided with a lower thermal insulating barrier spaced from the reactor vessel that has a hemispherical lower section that increases in volume from the center line of the reactor to the outer extent of the diameter of the thermal insulating barrier and smoothly transitions up the side walls of the vessel. The space between the thermal insulating harrier and the reactor vessel forms a chamber which can be flooded with cooling water through passive valving to directly cool the reactor vessel in the event of a severe accident. The passive inlet valve for the cooling water includes a buoyant door that is normally maintained sealed under its own weight and floats open when the cavity is Hooded. Passively opening steam vents are also provided.

Abstract: An embodiment of a nuclear power plant has: a reactor vessel containing a core; a reactor containment vessel containing the reactor vessel; and a radiation heat reflecting member disposed at a portion below the reactor vessel inside the reactor containment vessel. The radiation heat reflecting member may block radiation heat, which is emitted toward a side wall surface of the reactor containment vessel from the core that has been put in a molten state by an accident and flowed downward from the reactor vessel to be accumulated at a lower portion of the reactor containment vessel. The radiation heat reflecting member may block radiation heat, which is emitted toward a supporting structure supporting devices disposed inside the reactor containment vessel.

Abstract: A multi-layered material composite is disclosed suitable for nuclear reactor applications to protect equipment from radiation damage. In one embodiment, the composite includes an internal neutron-absorbing layer and an external layer disposed on opposing sides of the internal layer. The external layers are made of metal or ceramic in various embodiments. The composite is disposed on or at least proximate to the an equipment component within the containment chamber of a nuclear reactor in some embodiments to protect the component from radiation damage.

Abstract: A pressurized water reactor nuclear containment radiation shield which surrounds the upper portion of a pressure vessel in an ice condenser containment. The vertical walls of the neutron shield are formed in vertical sections with the lower and upper sections operable during outages, to open to promote air flow cooling along the walls in the vicinity of the vessel head.

Abstract: A fast reactor 1 includes: a reactor vessel 7 accommodating therein a core 2 and a primary coolant 21; a core support 13 supporting the core 2 from below; and a bulkhead 6 disposed on the core support 13, the bulkhead 6 extending upward and surrounding the core 2 from a lateral side. Between an inner surface of the reactor vessel 7 and the bulkhead 6, there is disposed an intermediate heat exchanger 15 configured to cool the primary coolant 21, and an electromagnetic pump 14 configured to pressurize the cooled primary coolant 21. A neutron shield 8 supported by an upper supporting plate 29 from above is disposed below the electromagnetic pump 14. The upper supporting plate 29 has an opening 29a. Between an outlet 14b of the electromagnetic pump 14 and the upper supporting plate 29, there is disposed a coolant guide mechanism 17 configured to guide the pressurized primary coolant 21 from the electromagnetic pump 14 to the neutron shield through the opening 29a of the upper supporting plate 29.

Abstract: In a nuclear reactor neutron panels varying in thickness in the circumferential direction are disposed at spaced circumferential locations around the reactor core so that the greatest radial thickness is at the point of highest fluence with lesser thicknesses at adjacent locations where the fluence level is lower. The neutron panels are disposed between the core barrel and the interior of the reactor vessel to maintain radiation exposure to the vessel within acceptable limits.

Abstract: In a reactor vessel thermal load reducing system near the surface level of a coolant, the present invention is characterized in that a heat conductive member is installed not contacting the reactor vessel wall in an area above and below the coolant liquid surface, and the heat conducting member is attached to a guard vessel, the heat conducting member being made of material of good heat conductivity.

Abstract: An isotope production system that includes a cyclotron having a magnet yoke that surrounds an acceleration chamber. The cyclotron is configured to direct a particle beam from the acceleration chamber through the magnet yoke. The isotope production system also includes a target system that is located proximate to the magnet yoke. The target system is configured to hold a target material and includes a radiation shield that extends between the magnet yoke and the target location. The radiation shield is sized and shaped to attenuate gamma rays emitted from the target material toward the magnet yoke. The isotope production system also includes a beam passage that extends from the acceleration chamber to the target location. The beam passage is at least partially formed by the magnet yoke and the radiation shield of the target system.

Abstract: Transport and storage of nuclear fuel assemblies may require double confinement depending on the circumstances. A device and a method are described to perform this double conditioning without the need of a hot containment, and in which the loading and pre-positioning steps can take place in a pool. The device (10) includes a metallic inner leak tight conditioning receptacle (20) and a metallic outer leak tight receptacle (30). When the inner receptacle (20) is located in the outer receptacle (30), a passage (15, 25) remains free between the two receptacles, from the open end to the bottom of the outer receptacle. The outer receptacle (30) can be drained through this passage, particularly by a dip tube (33).

Abstract: The present invention provides a method of manufacturing a core shroud for a nuclear plant and a nuclear power plant structure in which a groove portion is easily assembled in the case of manufacturing the core shroud having a weld structure of a nuclear power plant by a laser welding, and it is possible to obtain a weld joint portion in which a plastic distortion region and a residual stress are as small as possible, going with a solidification shrinkage of the weld portion. At a time of welding butted portions of a plurality of members constructing a core shroud, a root face is provided in the butted portion, a length of the root face is set to 25% to 95% of a thickness of the thinner one of the butted portions of a plurality of members, a narrow groove is provided in the other than the root face, and the butted portions are welded by a laser welding using a weld wire.

Abstract: An alignment system that employs jacking block assemblies and alignment posts around the periphery of the top plate of a nuclear reactor lower internals core shroud to align an upper core plate with the lower internals and the core shroud with the core barrel. The distal ends of the alignment posts are chamfered and are closely received within notches machined in the upper core plate at spaced locations around the outer circumference of the upper core plate. The jacking block assemblies are used to center the core shroud in the core barrel and the alignment posts assure the proper orientation of the upper core plate. The alignment posts may alternately be formed in the upper core plate and the notches may be formed in top plate.

Abstract: A reactor containment vessel of the present invention has a primary reactor containment vessel disposing a dry well for storing a reactor pressure vessel, a wet well for storing a pressure suppression pool, and an equipment room disposing below said pressure suppression pool inside thereof. Further, the primary reactor containment vessel includes an outer cylindrical wall reaching to a base mat from a top slab of the primary reactor containment vessel and facing the drywell, the pressure suppression pool and the equipment room respectively, an inner cylindrical wall facing the pressure suppression pool and the equipment room respectively, and a pressure suppression pool floor partitioning among the pressure suppression pool and the equipment room, and an outside portion of the outer cylindrical wall, an inside portion of the inner cylindrical wall, an outside portion of the ceiling and a lower portion of the pressure suppression pool floor are formed of a steel plate reinforced concrete respectively.

Abstract: The tie rod repair apparatus includes a tie rod secured at its upper end to the shroud flange at the top of the shroud. The lower end of the tie rod passes through an opening in the shroud support plate without imposing a load on the plate. The lower end of the tie rod is anchored to the lower end of the core shroud support cylinder such that the compressive load path exerted by the tie rod to restrain the cracked shroud passes directly through the shroud support cylinder and the assembly of shroud cylinders bypassing the shroud support plate.

Abstract: A neutron reactor includes a neutron shield which is disposed outside a nuclear reactor core and adapted to absorb neutrons leaking from the core. The neutron shield includes a plurality of containers each of which contains a powdered neutron absorbing material and which are stacked with one another in a vertical direction, and a cladding tube which houses the containers. The neutron absorbing material is composed of B4C powder.

Abstract: A method for carrying out a reactor internal, comprising steps of: forming a first opening portion in a ceiling of a reactor building at a position directly above an equipment pool in said reactor building; cutting a cylindrical reactor internal surrounding a core in a reactor pressure vessel disposed in said reactor building, at one position in an axial direction; surrounding said cut cylindrical reactor internal with a radiation shield; and carrying out said cylindrical reactor internal surrounded by said radiation shield out of said reactor building through said first opening portion.

Abstract: An alignment system that employs jacking block assemblies and alignment posts around the periphery of the top plate of a nuclear reactor lower internals core shroud to align an upper core plate with the lower internals and the core shroud with the core barrel. The distal ends of the alignment posts are chamfered and are closely received within notches machined in the upper core plate at spaced locations around the outer circumference of the upper core plate. The jacking block assemblies are used to center the core shroud in the core barrel and the alignment posts assure the proper orientation of the upper core plate. The alignment posts may alternately be formed in the upper core plate and the notches may be formed in top plate.

Abstract: Illustrative embodiments provide modular nuclear fission deflagration wave reactors and methods for their operation. Illustrative embodiments and aspects include, without limitation, modular nuclear fission deflagration wave reactors, modular nuclear fission deflagration wave reactor modules, methods of operating a modular nuclear fission deflagration wave reactor, and the like.

Abstract: Illustrative embodiments provide modular nuclear fission deflagration wave reactors and methods for their operation. Illustrative embodiments and aspects include, without limitation, modular nuclear fission deflagration wave reactors, modular nuclear fission deflagration wave reactor modules, methods of operating a modular nuclear fission deflagration wave reactor, and the like.

Abstract: The invention relates to a nuclear power station comprising: at least one high temperature reactor; a storage installation (14) for fuel elements (5); means (32) for transferring the fuel elements (5) between the core (4) and the storage installation (14). According to the invention, the transfer means (32) comprise a tunnel (34) for transferring the fuel elements between the reactor core (4) and the storage installation (14).

Abstract: A two-part integrated head assembly (100) is disclosed wherein the lower portion (110) attaches to, and is supported by, the reactor vessel closure head (90), and the upper portion (160) is fluidly connected to the lower portion, but is supported externally from the reactor vessel closure head. In the disclosed embodiment, the upper portion includes transverse support beams (170) that engage containment walls (92), for example steam generator walls, to support the upper portion. A duct (150) releasably connects a fan plenum (165) in the upper portion with an annular plenum in the lower portion, such that fans (166) can draw heated air from around the CEDMs (95). In one embodiment, a chiller (168) is provided in the fan plenum to cool the air prior to expelling it in containment. A missile shield (169) is also provided in the upper portion.

Abstract: Illustrative embodiments provide nuclear fission igniters for nuclear fission reactors and methods for their operation. Illustrative embodiments and aspects include, without limitation, a nuclear fission igniter configured to ignite a nuclear fission deflagration wave in nuclear fission fuel material, a nuclear fission deflagration wave reactor with a nuclear fission igniter, a method of igniting a nuclear fission deflagration wave, and the like.

Abstract: A nuclear reactor fuel bundle assembly including: a fuel bundle including an array of fuel rods and water rods mounted in an upper tie plate and housed in walls of a channel, and a pore type debris shield mounted at least partially in the channel, above or below the upper tie plate, the shield extending to or over the walls of the channel, whereby deflecting and/or capturing falling debris from entering the fuel assembly, wherein the shield is design to be durable, yet flexible, and porous.

Abstract: The invention consists of placing adequate and useable shielding in the path of the radiation that exists when nuclear workers perform maintenance and inspection of the Pressure Water Reactor Steam Generator component at a nuclear electric generating plant. The shielding has an upper and a lower track member that permit the two shield panel halves to roll easily and be manipulated so that access and the associated work to be performed will result in significant reduction to the typical radiation dose that the workers receive during this work evolution when compared current shielding approach. The shielding includes rollers that roll on track members that are located above and below the man-way opening.

Abstract: The invention places adequate and useable shielding in the path of the radiation that exists when nuclear workers perform maintenance and inspection of the Pressure Water Reactor Steam Generator component at a nuclear electric generating plant. The shielding has an upper and a lower track member that permit the two shield assembly halves to roll easily and be manipulated so that access and the associated work to be performed will result in significant reduction to the typical radiation dose that the nuclear workers receive during this work when compared with the current shielding approach. The shielding includes rollers that roll on track members that are located above and below the man-way opening.

Abstract: A rear door system for transferring hot cell equipment into or out of a hot cell is disclosed. The rear door system of the present invention includes a rear door, which is provided to a rear wall of the hot cell so as to be movable to open or close the rear wall of the hot cell, and a vertical moving table, which is provided at a predetermined position on the lower portion of the front surface of the rear door so as to be movable upwards or downwards. The rear door system further includes a drive unit, which is provided at a predetermined position in the lower end of the rear door to move the rear door, and a stationary working table, which is disposed above the vertical moving table and is fixed in the hot cell in a horizontal orientation. The rear door system further includes a removable table, which is removably coupled at a predetermined position to the stationary working table, and a hot cell crane hook and a service area crane hook, which are respectively provided inside and outside the hot cell.

Abstract: A head assembly for a reactor pressure vessel includes a removable closure head, an array of control rod drive mechanisms, a seismic support platform, a missile shield assembly and a cooling system for drawing atmospheric air across electromagnetic coil stack assemblies. The cooling system includes: a lower shroud surrounding the coil stack assemblies with an end open to the atmosphere around the CRDMs; a plurality of extending internal ducts disposed within the array of CRDMs upwardly to an upper plenum disposed above the seismic support platform and a plurality of fan assemblies disposed on the upper plenum. The missile shield is disposed within the upper plenum. The cooling system effectively cools the coil stack assemblies during fuel cycles and does not hinder access to the CRDMs during an outage. The head assembly has lift legs for transporting either the entire head assembly as an integral unit or the structure above the seismic support platform a subassembly.

Abstract: An integrated head assembly (100) is disclosed for a nuclear reactor. The preferred integrated head assembly includes a lift assembly (150) that supports the reactor vessel closure head (90) and integrated head assembly for removal, a separate support structure (202) supported by a ring beam (151) that sets atop the reactor vessel closure head, a shroud assembly (200), a seismic support system (300), a baffle assembly (500), a missile shield (400), and a CRDM cooling system. The CRDM cooling system draws cooling air into the baffle assembly, downwardly past the CRDMs (96), outwardly to upright air ducts (600), upwardly to an upper plenum (680), and out of the assembly through the air fans (190). In a second embodiment the integrated head assembly (1100) includes a missile shield (1400) and CRDM cooling system (1600) that permits access to individual CRDMs from above.

Abstract: In order to carry out a radioactivated reactor pressure vessel from a nuclear reactor building of a nuclear power plant, a first opening portion for carrying out the reactor pressure vessel is provided in a roof of the nuclear reactor building. A radiation shield for covering the reactor pressure vessel and shielding radiations is carried into the reactor building through the first opening portion, and installed on a reactor shield wall. A hanger is lowered through the first opening portion and a slit provided on an upper lid of the radiation shield. A portion of a lid of the reactor pressure vessel and a portion of the upper lid of the radiation shield are abutted by hanging up the reactor pressure vessel by the hanger.

Abstract: A shielded rack loader makes use of a loading rack movable between a shielding structure and a storage tube. A shield plug seals the storage tube. A hoist moves the shield plug and the loading rack. A shield plug cart and a material transfer cart mate with receiving flanges of the rack loader and permit temporary storage and movement of the shield plug and of canisters of transuranic material.

Abstract: A moulded shield for a source of gamma-rays said shield defining a cavity to receive said source and comprising a core layer of cured liquid silicone resin loaded with particulate gamma radiation-shielding material adapted to surround a radiation source located in said cavity, said core layer being located between two outer layers of solid polymeric material. Also a method of forming a tubular shield.