Patent Description:
In response to operational experience at a number of nuclear plants there is a clear need for increasing lifespan of thermal sleeves used in nuclear reactors. Thermal sleeve flange wear is a phenomenon first identified domestically in <NUM> when a part-length sleeve failed. Since then inspections have been recommended and acceptance criteria have been developed. More recently (December <NUM>), two additional thermal sleeve failures at rodded locations were identified.

<FIG> is a schematic cross-sectional view of an upper portion of a conventional nuclear reactor <NUM> illustrating a portion of a reactor vessel <NUM> penetrated by a plurality of head penetration adapters <NUM> which extend downward from a control rod drive mechanism (CRDM) housing <NUM>. Continuing to refer to <FIG>, as well as to the sectional view of <FIG>, a thermal sleeve <NUM> including a guide funnel <NUM> is positioned within each head penetration adapter <NUM> beneath each CRDM housing <NUM> such that each guide funnel <NUM> is positioned directly above, and spaced a distance from, a corresponding guide tube <NUM> extending from an upper support plate <NUM> within reactor vessel <NUM>. The thermal sleeve <NUM> is housed within the head penetration adapter <NUM> within the reactor vessel <NUM> except within region <NUM> (<FIG>) where the thermal sleeve <NUM> is exposed to the reactor coolant.

The current belief is that wear of thermal sleeve <NUM> and head penetration adapter <NUM> in region <NUM> illustrated in <FIG> and <FIG> results from rotation of the thermal sleeve <NUM> within the head penetration adapter <NUM> about a central axis <NUM> of the thermal sleeve <NUM>. It is believed that vortices in the reactor coolant flowing within the reactor vessel <NUM> come into contact with the thermal sleeve <NUM> (i.e., in region <NUM>) causing the thermal sleeve <NUM> to rotate about its central axis <NUM> relative to the head penetration adapter <NUM>.

<CIT> discloses tube lining sleeves that penetrate a nuclear reactor vessel top cover, cut in two with at least their lower part removed to enable repair of welds between sleeves and cover. <CIT> discloses a connector to provide a pressure boundary between a flanged nozzle and a concentric column, including a closure for compressing a seal ring against the nozzle flange that includes a hub defining an annular space between the closure and the column and graphite gaskets inserted into the annular space.

Embodiments of the disclosed concept increase the lifespan of thermal sleeves employed in nuclear reactors by reducing the wear of such sleeves and related components resulting from rotation of thermal sleeves within a head penetration adapter. In general, embodiments of the present invention utilize structures which can be readily attached, either during installation of a thermal sleeve or retrofit to an installed thermal sleeve, that resist, reduce, and/or prevent the thermal sleeve from rotating, but still allow for axial movement of the sleeve, such as due to thermal expansion/contraction and/or to allow the passage of reactor coolant when necessary. In other words, the structures attachable to the thermal sleeve and/or the head penetration adapter are configured to resist rotation of the thermal sleeve which may result due to vortices of coolant flow within the reactor which come into contact with the thermal sleeve.

As one aspect of the disclosed concept, a device for resisting (e.g. reducing and/or preventing) rotation of a thermal sleeve about a central axis thereof relative to a head penetration adapter in a nuclear reactor is provided. The device comprises a first structure and a second structure. The first structure and the second structure are configured to be operably engaged to resist rotation of the thermal sleeve about the central axis relative to the head penetration adapter while allowing axial movement of the thermal sleeve relative to the head penetration adapter.

The first structure comprises a first ring configured to be coupled to the thermal sleeve, the first ring having a plurality of rod members extending therefrom, each rod member extending along a respective rod axis that is parallel to the central axis when the first structure is coupled to the one of the thermal sleeve.

The second structure comprises a second ring configured to be coupled to the thermal sleeve, the second ring having a plurality of thru-holes formed therein, each thru-hole defines a thru-hole axis that is parallel to the central axis when the second ring is coupled to the head penetration adapter, and wherein each rod member of the first ring is configured to slidingly engage a corresponding thru-hole of the second ring.

The first ring may be formed of a stainless steel material, and the second ring may be formed from an alloy.

The second ring may comprise a female threaded portion which is configured to engage a cooperatively male threaded portion of the head penetration adapter.

The second ring may comprise an inner stepped portion configured to receive a lower end of the head penetration adapter.

The second ring may comprise a first segment and a second segment selectively couplable to the first segment.

The plurality of rod members may comprise two rod members.

The first ring may be split into a first segment and a second segment.

The first segment and the second segment may each include interlocking portions, wherein the first segment and the second segment are couplable together via the interlocking portions.

The first ring may comprise a first piece and a second piece separate from the first piece, the first piece may include one rod member of the plurality of rod members, and the second piece may include another rod member of the plurality of rod members.

Each rod member may have a non-circular cross-section and each thru-hole may have a correspondingly-shaped non-circular cross-section.

One of the first structure or the second structure may comprise a mechanical clamp configured to mechanically couple the one of the first structure or the second structure to the thermal sleeve or the head penetration adapter.

One of the first structure or the second structure may comprise a split clamp configured to be coupled to the thermal sleeve, the split clamp formed from two segments which are configured to be selectively coupled together via threaded fasteners.

One of the two segments may include pockets formed therein for engagement by crimped portions of one of the threaded fasteners.

The one of the first structure or the second structure may further comprise rods, the other one of the first structure or the second structure may comprise axial slots formed in the head penetration adapter, and each rod may be configured to engage a respective axial slot.

The first structure may comprise a main body portion configured to be coupled to a head penetration adapter, the main body portion may include a plurality of horizontally oriented apertures formed therein with each aperture housing a sliding member therein, the second structure may comprise a plurality of slots defined in the thermal sleeve, and each sliding member may be configured to engage a corresponding slot.

As another aspect of the disclosed concept, there is provided a nuclear reactor vessel comprising a head penetration adapter, a thermal sleeve, and a device for resisting rotation of the thermal sleeve about a central axis thereof relative to the head penetration adapter according to the above aspect.

The device comprises a first structure provided on the thermal sleeve, and a second structure provided on the head penetration adapter. The first structure and the second structure are configured to be operably engaged to resist rotation of the thermal sleeve about the central axis relative to the head penetration adapter while allowing axial movement of the thermal sleeve relative to the head penetration adapter.

Various features of the embodiments described herein, together with advantages thereof, may be understood in accordance with the following description taken in conjunction with the accompanying drawings as follows:.

Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate various embodiments of the invention, in one form, and such exemplifications are not to be construed as limiting the scope of the invention in any manner.

It has been observed that thermal sleeves have been wearing between the upper head on the thermal sleeve and the head penetration adapter. This wear is observed by taking measurements using laser metrology to determine the amount that a particular thermal sleeve has "dropped" relative to the head penetration adapter. As part of an innovation program, methods for removing worn thermal sleeves and replacing them with a temporary "compressible thermal sleeve" was developed, which does not require removal of the CRDM motor assembly from the top side of the reactor head. Such methods and replacement thermal sleeves are described in pending <CIT>. However, the mechanism of failure (i.e., wearing of the thermal sleeve and head penetration adapter) was not addressed, and a compressible thermal sleeve will most likely continue to wear along with the head penetration adapter in a similar manner to the worn thermal sleeve which has been replaced.

A solution to reduce and/or preventing such wear is to install a device on to the head penetration adapter which will create an interface for a second device which is attached to the thermal sleeve. Once the two devices are in place and interfaced with one another, the degrees of freedom of the thermal sleeve are limited, removing rotation about the centerline axis of the thermal sleeve. Embodiments of the concept generally utilize a ring or similar structure which is attached to the head penetration adapter by various methods depending on the design of the head penetration adapter. The device may attach to the threads or interface with the outer diameter of the head penetration adapter. The device is fixed and retained by any suitable mechanical means, such as, without limitation, welding, clamping, pinning, screwing, etc., and/or combinations thereof. In at least one embodiment, the device is integral to the head penetration adapter. The device includes features such as holes, slots, splines or keyways which are engaged by a mating device attached to the thermal sleeve. The device which attaches to the thermal sleeve can be attached by any suitable mechanical means such as welding, clamping, pinning, screwing, etc.. In at least one embodiment, the device which attaches to the thermal sleeve is integral to the thermal sleeve design. The engagement of the splines or keys will prevent most of the relative rotational motion of the thermal sleeve and the head penetration adapter. This motion is the source of the wear which leads to thermal sleeve failure. By restricting this motion, the functional life of the thermal sleeves is greatly extended. In at least one embodiment, the device or devices resist, reduce, and/or prevent rotational motion of the thermal sleeve relative to the head penetration adapter while allowing some axial movement of the thermal sleeve relative to the head penetration adapter.

There are generally two applications for such solutions. The first application incorporates the device(s) into a replacement compressible thermal sleeve. The second application incorporates the device(s) on an existing thermal sleeve which has shown some wear within acceptable limits.

Alternative designs include, for example, attaching a device to the head penetration adapter which interfaces with features machined into the thermal sleeve which meet the design intention of resisting, reducing, and/or preventing rotation and/or translation (one or both).

Before explaining various aspects of the present disclosure in detail, it should be noted that the illustrative examples are not limited in application or use to the details of construction and arrangement of parts illustrated in the accompanying drawings and description. The illustrative examples may be implemented or incorporated in other aspects, variations, and modifications, and may be practiced or carried out in various ways. Further, unless otherwise indicated, the terms and expressions employed herein have been chosen for the purpose of describing the illustrative examples for the convenience of the reader and are not for the purpose of limitation thereof. Also, it will be appreciated that one or more of the following-described aspects, expressions of aspects, and/or examples, can be combined with any one or more of the other following-described aspects, expressions of aspects, and/or examples.

<FIG> depict a device <NUM> configured to resist, reduce, and/or prevent rotation of a thermal sleeve <NUM> about a central axis CA thereof relative to a head penetration adapter <NUM> in a nuclear reactor. <FIG> illustrates the device <NUM> installed on portions of the head penetration adapter <NUM> and the thermal sleeve <NUM>. The arrangement includes a first structure, or a first ring <NUM>, which is coupled (e.g., via welds <NUM>) to the thermal sleeve <NUM>. Various welds are depicted in a number of embodiments of the present disclosure as filet welds. This, however, should not be construed as limiting. Other suitable welds for use with the embodiments of the present disclosure are contemplated. The first ring includes a plurality of rod members <NUM> extending therefrom. More specifically, each rod member <NUM> extends from the first ring <NUM> along a rod axis RA which is parallel to the central axis CA when the first ring <NUM> is coupled to the thermal sleeve <NUM>. In the illustrated embodiment, the rod members <NUM> are symmetrical with respect to the central axis CA, however, other embodiments are envisioned where the rod members <NUM> are not symmetrical. In certain embodiments, one or more of the rod members <NUM> extend along respective rod axes that are not parallel to the central axis CA. In at least one embodiment, the first ring <NUM> is formed from a stainless steel material.

Referring primarily to <FIG> and <FIG>, the device <NUM> further includes a second structure, or second ring <NUM>, coupled to the head penetration adapter <NUM>. The second ring <NUM> comprises an internal diameter including a threaded portion <NUM> which engages a cooperative threaded portion on the outside diameter of the head penetration adapter <NUM>. Head penetration adapters for certain types of reactors comprise threaded portions on the outside diameter of their bottom end. For head penetration adapters without such threaded portions, the head penetration adapter may be machined via any suitable means to create a threaded portion to receive the threaded portion <NUM> of the second ring <NUM>, for example. The second ring <NUM> includes a plurality of thru-holes <NUM> formed therein, with each thru-hole <NUM> defining a thru-hole axis THA. In the illustrated embodiment, the thru-holes <NUM> are equally radially spaced approximately ninety degrees apart about the central axis CA, however, other embodiments are envisioned where the thru-holes <NUM> are not equally radially spaced. In at least one embodiment, the second ring <NUM> is formed from an alloy. Each rod member <NUM> of the first ring <NUM> is configured to engage a corresponding thru-hole <NUM> of the second ring <NUM> to resist, reduce, and/or prevent rotation of the thermal sleeve <NUM> about its central axis CA relative to the head penetration adapter <NUM>, while allowing axial movement of the thermal sleeve <NUM> relative to the head penetration adapter <NUM>. For example, axial movement of the thermal sleeve <NUM> relative to the head penetration adapter can be caused by thermal expansion/contraction of the thermal sleeve <NUM> and/or may be necessary to allow the passage of reactor coolant flow. <FIG> illustrate further views of the second ring <NUM> coupled to the lower portion of the head penetration adapter <NUM>. As shown in <FIG>, the second ring <NUM> is further secured to the head penetration adapter by a plurality of welds <NUM> in addition to the threaded connection previously discussed.

Referring primarily to <FIG>, the first ring <NUM> may initially be installed onto a newly installed replacement thermal sleeve <NUM>. Clearance is provided between the inner diameter of the first ring <NUM> and the outer diameter of the thermal sleeve <NUM> to allow the first ring <NUM> to be slid along and/or rotated about the thermal sleeve <NUM> to a desired position. The second ring <NUM> is coupled to the bottom portion of the head penetration adapter <NUM> as discussed above. The first ring <NUM> is then slid into engagement with the second ring <NUM> (<FIG>) and then suitably coupled (e.g., via welding or any suitable attachment method) to the thermal sleeve <NUM> in the desired position.

<FIG> depict a second ring <NUM>' for use with the first ring <NUM> in place of the second ring <NUM>. The second ring <NUM>' comprises an inner stepped portion <NUM>' for receiving the lower end of a head penetration adapter <NUM> and through holes <NUM>' for interfacing with the rod members <NUM> of the first ring <NUM>. In the illustrated embodiment, the second ring <NUM>' is attached to the head penetration adapter <NUM> via welds <NUM>'. However, any suitable attachment method may be utilized to attach the second ring <NUM>' to the bottom portion of the head penetration adapter <NUM>.

<FIG> depict another a second ring <NUM>" for use with the first ring <NUM> in place of the second ring <NUM>. The second ring <NUM>' comprises a first arcuate portion <NUM>" and a second arcuate portion <NUM>" configured to be mated together around a portion, such as the bottom end of the head penetration adapter <NUM> to form a circular ring. Each of the first portion <NUM>" and the second portion <NUM>" comprises a stepped portion <NUM>" for receiving the bottom end of the head penetration adapter <NUM> when the first portion <NUM>" and the second portion <NUM>" are mated together. Further, each of the first portion <NUM>" and the second portion <NUM>" comprise a plurality of through holes <NUM>" therein. The through holes <NUM>" are similar to the through holes <NUM> previously described (<FIG>). The first portion <NUM>" comprises a female interlock portion <NUM>" at both ends and the second portion <NUM>" comprises a male interlock portion <NUM>" at both ends. The female interlock portions <NUM>" are configured to receive the male interlock portions <NUM>" to form the second ring <NUM>". Once mated together around the bottom end of the penetration adapter <NUM>, the second ring <NUM>" can be welded in the female and male interlock regions <NUM>", <NUM>" to prevent the second ring <NUM>" from coming apart in service. In other embodiments, the first portions <NUM>" and the second portions <NUM>" are each modified to include one female interlock portion on one end thereof and one male interlock portion on the other end.

In at least one embodiment, the second ring <NUM>" can be retro-fit onto an already installed thermal sleeve <NUM>. As illustrated in <FIG>, the first portion <NUM>" and the second portion <NUM>" are positioned around the head penetration adapter <NUM> and mated together to form the second ring <NUM>". Once the second ring <NUM>" is in the desired position, the second ring <NUM>" can be secured to the head penetration adapter <NUM> via welds <NUM>", as shown in <FIG>. In at least one embodiment, the second ring <NUM>" can be used in conjunction with the first ring <NUM> in the manner describe above with regard to <FIG>,<FIG>, <FIG>, for example. However, other embodiments are contemplated for use with the second ring <NUM>", as discussed in greater detail below.

<FIG> depict a first ring <NUM>" configured to be attached to the thermal sleeve <NUM> and mate with the second ring <NUM>" which is attached to the head penetration adapter <NUM>, as discussed above. The first ring <NUM>" comprises a first portion <NUM>" and a second portion <NUM>". The first portion <NUM>" comprises a first upstanding rod member <NUM>" configured to be received within one of the through holes <NUM>" in the second ring <NUM>". The second portion <NUM>" comprises a second upstanding rod member <NUM>" configured to be received within another one of the through holes <NUM>" in the second ring <NUM>". Once the first portion <NUM>" and the second portion <NUM>" are in the desired position, welds <NUM>" are applied to secure the first portion <NUM>" and the second portion <NUM>" to the thermal sleeve <NUM>. As can be seen in <FIG>, each of the first portion <NUM>" and the second portion <NUM>" comprises less than half of a full circumference. The first portion <NUM>" and the second portion <NUM>" are sized in this manner to permit variability of the installation positions and/or weld locations.

Further to the above, <FIG> illustrates a cut location <NUM> on the thermal sleeve <NUM> where the thermal sleeve <NUM> may be cut in order to allow for the installation of the devices discussed herein onto the head penetration adapter <NUM> and/or the remaining portion of the thermal sleeve <NUM>. Once the assembly is complete, the thermal sleeve <NUM> is welded back together.

<FIG> depict a device <NUM> configured to resist, reduce, and/or prevent rotation of the thermal sleeve <NUM> about an axis thereof relative to the head penetration adapter <NUM>. The device <NUM> comprises a first ring <NUM> configured to be attached to a thermal sleeve <NUM> and a second ring <NUM> configured to be attached to the head penetration adapter <NUM>. The first ring <NUM> and the second ring <NUM> are configured for operable engagement to resist, reduce, and/or prevent rotation of the thermal sleeve <NUM> relative to the head penetration adapter <NUM>, as discussed in greater detail below.

The first ring <NUM> comprises a body <NUM> and two upstanding rod members <NUM> extending from the ring body <NUM>. The ring body <NUM> comprises an opening <NUM> sized such that the first ring <NUM> can slide onto the thermal sleeve <NUM>. In the illustrated embodiment, the upstanding rod members <NUM> comprise an ellipse cross-section that is non-circular. However, other embodiments are envisioned where the upstanding rod members <NUM> comprise a cylindrical shape, such as the rod members <NUM> illustrated in <FIG>. In any event, the second ring <NUM> comprises a ring body <NUM> including two lug members <NUM> extending laterally therefrom. An opening <NUM> and a cutout region <NUM> are defined in the ring body <NUM>. The opening <NUM> is sized such that the second ring <NUM> can be slid along the thermal sleeve <NUM> and abut against the bottom end of the head penetration adapter <NUM>. More specifically, the cutout region <NUM>, provided in the body <NUM> of the second ring <NUM>, receives the bottom end of the head penetration adapter <NUM>. The lug members <NUM> comprise openings <NUM> therein which are sized and shaped to receive the upstanding rod members <NUM> when the first ring <NUM> and the second ring <NUM> are assembled together as illustrated in <FIG>.

In use, the second ring <NUM> can already be attached to a replacement thermal sleeve <NUM> or can be retrofit to an existing thermal sleeve as described herein. The second ring <NUM> is slid along the thermal sleeve <NUM> until the bottom end of the head penetration adapter <NUM> is received in the cutout region <NUM> of the second ring <NUM>. An already installed thermal sleeve <NUM> may be cut, as discussed above, in order to receive the second ring <NUM>. The second ring <NUM> is then welded to the head penetration adapter <NUM> via welds <NUM>. The first ring <NUM> is then installed onto the thermal sleeve <NUM> and slid along the thermal sleeve <NUM> until the upstanding rod members <NUM> are received within their respective openings <NUM> in the second ring <NUM>. Once the first ring <NUM> is in the desired position, the first ring <NUM> is welded to the thermal sleeve <NUM>. The first ring <NUM> is engaged with the second ring <NUM> to resist, reduce, and/or prevent the thermal sleeve <NUM> from rotating about an axis thereof. However, the thermal sleeve <NUM> is permitted to axially translate due to the relationship between the upstanding rod members <NUM> and the openings <NUM>.

<FIG> depict a device <NUM> configured to resist, reduce, and/or prevent rotation of the thermal sleeve <NUM> about an axis thereof relative to the head penetration adapter <NUM>. The device <NUM> comprises a first ring <NUM> configured to be attached to a thermal sleeve <NUM> and the second ring <NUM>, discussed above with regard to <FIG>, configured to be attached to the head penetration adapter <NUM>. The first ring <NUM> and the second ring <NUM> are configured for operable engagement to resist, reduce, and/or prevent rotation of the thermal sleeve <NUM> relative to the head penetration adapter <NUM>, as discussed in greater detail below.

The first ring <NUM> comprises a body <NUM> and two upstanding rod members <NUM> extending from the ring body <NUM>. The ring body <NUM> comprises an opening <NUM> sized such that the first ring <NUM> can slide along the thermal sleeve <NUM>. In the illustrated embodiment, the upstanding rod members <NUM> comprise an ellipse cross-section that is non-circular. However, other embodiments are envisioned where the upstanding members <NUM> comprise a cylindrical shape, such as the rod members <NUM> illustrated in <FIG>.

Further to the above, the ring body <NUM> comprises a mechanical clamp <NUM> extending therefrom. The mechanical clamp <NUM> comprises an inner housing <NUM> extending from the body <NUM> of the first ring <NUM> and an outer housing <NUM> positionable around the inner housing <NUM>. The outer housing <NUM> comprises internal threads <NUM> and the inner housing <NUM> comprises cooperative external threads <NUM>. Thus, when assembled together, the threads <NUM> of the outer housing <NUM> are engaged with the threads <NUM> of the inner housing <NUM> such that, as the outer housing <NUM> is rotated, the outer housing <NUM> will translate relative to the inner housing <NUM>.

Further to the above, the inner housing <NUM> comprises a collet <NUM> including a plurality of fingers <NUM>. The fingers <NUM> of the collet <NUM> are configured to flex inward when an external force is applied to the collet <NUM>. In the illustrated example, the fingers <NUM> of the collet <NUM> comprise tapered outer surfaces <NUM> which are aligned with a tapered inner surface <NUM> of the outer housing <NUM> when the outer housing <NUM> is threadably engaged with the inner housing <NUM>. When the outer housing <NUM> is rotated in the counter clockwise direction DCCW, for example, the outer housing <NUM> will translate in direction D1 and the tapered inner surface <NUM> of the outer housing <NUM> will engage the tapered outer surfaces <NUM> of the inner housing <NUM> and deflect the fingers <NUM> inward. Other embodiments are envisioned where the outer housing <NUM> is rotatable in a clockwise direction to translate the outer housing <NUM> in direction D1.

In use, the second ring <NUM> is slid along the thermal sleeve <NUM> until the bottom end of the head penetration adapter <NUM> is received in the cutout region <NUM> of the second ring <NUM>. An already installed thermal sleeve <NUM> may be cut, as discussed above, in order to receive the second ring <NUM>. The second ring <NUM> is then welded to the head penetration adapter <NUM>. The first ring <NUM> is then installed onto the thermal sleeve <NUM> and slid along the thermal sleeve <NUM> until the upstanding rod members <NUM> are received within their respective openings <NUM> in the second ring <NUM>. Once the first ring <NUM> is at the desired position, the mechanical clamp <NUM> can be actuated to secure the first ring <NUM> to the thermal sleeve <NUM>. More specifically, the outer housing <NUM> of the mechanical clamp <NUM> can be rotated, as discussed above, to clamp the inner housing <NUM> onto the thermal sleeve <NUM>. Openings <NUM> in the outer housing <NUM> of the mechanical clamp <NUM> may be utilized to facilitate rotation of the outer housing <NUM> to secure the first ring <NUM> to the thermal sleeve <NUM>. In at least one embodiment, the openings <NUM> may be engage by a wrench or any suitable tool to aid the user in rotating the outer housing <NUM> relative to the inner housing <NUM>.

Further to the above, the outer housing <NUM> comprises a crimp ring portion <NUM> that is configured to be deformed into corresponding slots <NUM> defined in the outer diameter of the inner housing <NUM> of the first ring <NUM> after the inner housing <NUM> is clamped to the thermal sleeve <NUM>. The slots <NUM> are radially positioned around the outer diameter of the inner housing <NUM>. The crimp ring portion <NUM> is configured to be bent and/or deflected into the slots <NUM> to prevent the outer housing <NUM> from becoming disengaged with the inner housing <NUM> (i.e., prevents the outer housing <NUM> from unthreading itself from the inner housing <NUM> in service).

Further to the above, when the first ring <NUM> is attached to the thermal sleeve <NUM>, the second ring <NUM> is attached to the head penetration adapter <NUM>, and the first ring <NUM> and second ring <NUM> are operably engaged, the device <NUM> resists, reduces, and/or prevents the thermal sleeve <NUM> from rotating about an axis thereof. However, the thermal sleeve <NUM> is permitted to axially translate due to the relationship between the upstanding rod members <NUM> and the openings <NUM>.

<FIG> depict a split clamp assembly <NUM> configured to resist, reduce, and/or prevent rotation of the thermal sleeve <NUM> about an axis thereof relative to a modified head penetration adapter <NUM>'. The split clamp assembly <NUM> comprises a first clamp portion <NUM> and a second clamp portion <NUM> configured to be coupled together via fasteners <NUM>. The first clamp portion <NUM> comprises an arcuate body <NUM> including two lug portions <NUM> extending therefrom. Each of the lug portions <NUM> comprises a threaded hole therein. A pair of upstanding members <NUM> extend from the lug portions <NUM>. In the illustrated embodiment, the upstanding members <NUM> comprise a rectangular cross-section with rounded edges. However, other embodiments are envisioned where the upstanding members <NUM> comprise a cylindrical shape, or any other suitable shape for engagement with a modified head penetration adapter. In any event, the second clamp portion <NUM> comprises an arcuate body <NUM> including two lug portions <NUM> extending therefrom. The arcuate body <NUM> of the first clamp portion <NUM> and the arcuate body <NUM> of the second clamp portion <NUM> form an opening <NUM> therebetween when the first clamp portion <NUM> and the second clamp portion <NUM> are coupled together. The opening <NUM> is sized and shaped to receive the thermal sleeve <NUM>. In the illustrated embodiment, the opening <NUM> is substantially circular. However, in other embodiments, the opening <NUM> can comprise a different shape suitable for receiving a thermal sleeve <NUM> such as, for example, an oval shape.

Further to the above, the second clamp portion <NUM> comprises protrusions <NUM> extending from each of the lug portions <NUM>. Each of the protrusions <NUM> comprises an opening <NUM> therein which terminates in a step <NUM>. A threaded hole <NUM> extends through the remainder of the protrusion <NUM> and the lug portion <NUM> on each side of the second clamp portion <NUM>. The threaded holes <NUM> are positioned such that they align with the threaded holes defined in the first clamp portion <NUM> when the first clamp portion <NUM> and the second clamp portion <NUM> are coupled together. Each of the openings <NUM> comprises a plurality of cutouts, or pockets <NUM> in the sidewall thereof. In at least one embodiment, each opening <NUM> comprises four pockets <NUM> that are equally radially spaced within the inner diameter of the opening <NUM>. However, other embodiments are envisioned with more or less than four pockets <NUM> that can be equally, or non-equally, radially spaced within the inner diameter of the opening <NUM>.

In use, the first clamp portion <NUM> is positioned on one side of the thermal sleeve <NUM> and the second clamp portion <NUM> is positioned on another side of the thermal sleeve <NUM>. Once the first clamp portion <NUM> and the second clamp portion <NUM> are at the desired position relative to the modified head penetration adapter <NUM>', the split clamp assembly <NUM> can be clamped around the thermal sleeve <NUM> by installing the fasteners <NUM>. The split clamp assembly <NUM> can be positioned relative to the modified head penetration adapter <NUM>' such that the upstanding members <NUM> of the split clamp assembly <NUM> are received within axial slots <NUM>' defined in the modified head penetration adapter <NUM>'. In at least one embodiment, the axial slots <NUM>' are defined into the bottom end of the head penetration adapter <NUM> to create a modified head penetrations adapter <NUM>', for example.

Further to the above, the fasteners <NUM> are configured to threadably engage the threaded holes <NUM> in the second clamp portion <NUM> and extend into the threaded holes in the first clamp portion <NUM>. As the fasteners are tightened, the opening <NUM> will decrease in size and squeeze the split clamp assembly <NUM> around the thermal sleeve <NUM>'. When the fasteners <NUM> are installed, the head of each fastener <NUM> may eventually bottom out on the step <NUM> within each opening <NUM>. Each fastener <NUM> comprises a crimp portion <NUM> which can be deformed once the fastener <NUM> is installed into the split clamp assembly <NUM>. More specifically, the crimp portion <NUM> can be deflected into the pockets <NUM> within the sidewalls of the opening <NUM> to retain the fasteners <NUM> within the split clamp assembly <NUM>. By crimping the crimp portions <NUM>, the fastener is prevented from rotating and prevented from becoming a loose part if the fastener <NUM> fails in service. In at least one embodiment, after clamping the split clamp assembly <NUM> to the thermal sleeve <NUM>, the split clamp assembly <NUM> can be welded to the thermal sleeve <NUM>.

Further to the above, the relationship between the upstanding members <NUM> and the axial slots <NUM>' in the head penetration adapter <NUM>' resist, reduce, and/or prevent rotation of the thermal sleeve <NUM> while permitting axial movement of the thermal sleeve <NUM> relative to the head penetration adapter <NUM>'.

<FIG> depict a device <NUM> configured to resist, reduce, and/or prevent rotation of the thermal sleeve <NUM> about an axis thereof relative to the head penetration adapter <NUM>. The device <NUM> comprises a split clamp assembly <NUM>', configured to be attached to a thermal sleeve <NUM>, and the second ring <NUM> (see <FIG> and <FIG>) configured to be attached to the head penetration adapter <NUM>. The split clamp assembly <NUM>' and the second ring <NUM> are configured for operable engagement to resist, reduce, and/or prevent rotation of the thermal sleeve <NUM> relative to the head penetration adapter <NUM>, as discussed in greater detail below.

The split clamp assembly <NUM>' is similar to the split clamp assembly <NUM> except the split clamp assembly <NUM>' comprises upstanding members <NUM>' which comprise an ellipse cross-section that is non-circular. However, other embodiments are envisioned where the upstanding members <NUM>' comprise a cylindrical shape, such as the rod members <NUM> illustrated in <FIG>.

In use, the second ring <NUM> is attached (e.g., welded) to the head penetration adapter <NUM> as previously discussed with regard to <FIG> and <FIG>. Then, the split clamp assembly <NUM>' is positioned around the thermal sleeve <NUM> as was as discussed above with regard to split clamp assembly <NUM>. The split clamp assembly <NUM>' is then slid towards the head penetration adapter <NUM> until the upstanding rod members <NUM>' are received in the openings <NUM> of the second ring <NUM>. Once the desired positioned is achieved, the split clamp assembly <NUM>' can be clamped to the thermal sleeve <NUM> by tightening the fasteners <NUM> as was previously discussed. In at least one embodiment, after clamping the split clamp assembly <NUM>' to the thermal sleeve <NUM>, the split clamp assembly <NUM>' can be welded to the thermal sleeve <NUM>.

<FIG> depict a device <NUM> configured to resist, reduce, and/or prevent rotation of a modified thermal sleeve <NUM>' about an axis thereof relative to a head penetration adapter <NUM>. The device <NUM> comprises a cylindrical body portion <NUM> comprising a through hole <NUM> therein. The through hole <NUM> defines a central axis CA and is configured to receive the thermal sleeve <NUM>'. The body portion <NUM> further comprises a stepped portion <NUM> configured to receive the bottom end of the head penetration adapter <NUM>. As illustrated in <FIG>, the body portion <NUM> further comprises a pair of through holes <NUM> spaced on either side of the central axis CA. The through holes <NUM> define axes that are perpendicular to the central axis CA. Each of the through holes <NUM> widen to a counter bore <NUM> defined in the outer diameter of the body portion <NUM>. The device <NUM> further comprises a slidable member <NUM> including a head portion <NUM>. The slidable members <NUM> are configured to slide within the through holes <NUM> and the head portion <NUM> of the slidable member <NUM> is configured to be receive in the counter bore <NUM> of the body portion <NUM> of the device <NUM>.

Further to the above, axial slots <NUM>' are defined one either side of a shaft axis SA defined by the modified thermal sleeve <NUM>'. In at least one embodiment, the axial slots <NUM>' are machined into an existing thermal sleeve <NUM> to create the modified thermal sleeve <NUM>'. The axial slots <NUM>' are positioned on either side of the shaft axis SA of the modified thermal sleeve <NUM>'. The shaft axis SA of the modified thermal sleeve <NUM>' is coincident with the central axis of the device <NUM> when the device <NUM> is assembled to the head penetration adapter <NUM> and the modified thermal sleeve <NUM>', as discussed in greater detail below.

In use, the device <NUM> is slid onto the modified thermal sleeve <NUM>' and translated towards the head penetration adapter <NUM> until the stepped portion <NUM> of the device <NUM> engages the bottom end of the head penetration adapter <NUM>. The device <NUM> is then rotated until the slidable members <NUM> are aligned with the axial slots <NUM>' in the modified thermal sleeve <NUM>'. The body portion <NUM> of the device <NUM> is then welded to the head penetration adapter <NUM> as illustrated in <FIG>. The slidable members <NUM> can then be slid into the axial slots <NUM>' of the modified thermal sleeve <NUM>' and the head portions <NUM> of the slidable members <NUM> are then welded to the body portion <NUM> of the device <NUM>. The slidable members <NUM> and axial slots <NUM>' are sized and shaped such that, when the slidable members <NUM> are received in the axial slots <NUM>', rotational movement of the modified thermal sleeve <NUM>' about the shaft axis SA thereof is restricted while permitting some amount of axial translation of the modified thermal sleeve <NUM>' along the shaft axis SA relative to the head penetration adapter <NUM>.

Further to the above, in at least one alternative embodiment, the slidable members <NUM> comprise external threads that mate with internal threads defined within the through holes <NUM> of the device <NUM>. In such an arrangement, the slidable members <NUM> are threadably engaged with the body portion <NUM> of the device and can be rotated to translate the slidable members <NUM> into the axial slots <NUM>' of the modified thermal sleeve <NUM>'. Further, welds may be applied to the head portions <NUM> of the slidable members <NUM> after the slidable members <NUM> are installed.

From the foregoing example embodiments, it is thus to be appreciated that some novel features of the disclosed concept are that the design can be implemented on both replacement compressible thermal sleeves as well as on an existing thermal sleeve. The parts utilized in such arrangements are designed to interface between stationary and movable components composed of different materials. Embodiments of the concept must function submerged in an elevated temperature, highly turbulent environment. Much of the novelty of the device is to allow axial movement of the sleeve during head installation, while restricting motions induced by turbulent cross-flow. The spline/keyway design permits axial motion while restraining the <NUM> other degrees of freedom (translations perpendicular to the thermal sleeve axis and all rotations). It is to be appreciated that the arrangements provided herein may generally be reversed (i.e., coupled to the alternative of the head penetration adapter/thermal sleeve) without varying from the scope of the present disclosure.

As an alternative to the embodiments previously discussed which minimize/eliminate wear to one or both of the thermal sleeve and/or the associated head penetration adapter by inhibiting rotation of the thermal sleeve by utilizing interacting elements coupled to the thermal sleeve and the penetration adapter, the disclosed concept also provides embodiments which utilize interactions between the guide funnel of a thermal sleeve and one or more elements coupled to the corresponding guide tube below. An arrangement of a plurality of guide tubes <NUM> in which a guide tube <NUM>' thereof has been modified in accordance with at least one embodiment of the disclosed concept is shown in <FIG>. More particularly, modified guide tube <NUM>' has been modified to include a plurality (two are shown) of threaded blind holes <NUM> formed in the top thereof. In at least one embodiment, the threaded blind holes <NUM> were formed by first forming blind holes via EDM, with tapping thereof then carried out using a conventional tap, remotely operated. It is to be appreciated, however, that threaded blind holes <NUM> may be formed via any other suitable method without varying from the scope of the present disclosure. It is also to be appreciated that the quantity of threaded blind holes <NUM> may be varied without varying from the scope of the present disclosure.

Referring now to <FIG> and <FIG>, a wear mitigation device <NUM> is depicted. The wear mitigation device <NUM> includes a base <NUM>, formed as a circular ring, that is configured to be coupled to the guide tube <NUM>' and a plurality of protruding elements, or protruding members <NUM>, each extending upward from the base <NUM>, that are sized and configured to engage a guide funnel of a thermal sleeve, as will be discussed in further detail below. The wear mitigation device <NUM> shown in the figures includes four protruding members <NUM>, however, it is to be appreciated that the quantity of protruding members <NUM> may be varied without varying from the scope of the present disclosure.

To facilitate coupling of the base <NUM> to the modified guide tube <NUM>', the base <NUM> includes a plurality of apertures <NUM> defined therethrough. Each aperture <NUM> is positioned so as to align with a corresponding one of the plurality of threaded blind holes <NUM> of modified guide tube <NUM>' and to receive a threaded bolt <NUM> therethrough, such as shown in <FIG>, which threadingly engages the corresponding threaded blind hole <NUM>. In order to prevent each threaded bolt <NUM> from loosening, the base <NUM> further includes a plurality of collars <NUM>, with each collar <NUM> being disposed about a corresponding one of the apertures <NUM> and extending upward from the base <NUM>, as shown in <FIG>. Each collar <NUM> is deformable inward toward the head portion of each threaded bolt <NUM> via a crimping tool or other suitable mechanism in a manner such that the collar <NUM> may be deformed against the head portion of the bolt <NUM>, thus preventing rotation of the bolt <NUM>. Additionally, the collar <NUM> prevents loose parts from being introduced into the reactor in the unlikely event of the head portion of the bolt <NUM> separating from the remainder of bolt <NUM>. In order to properly align the base <NUM> with the guide tube <NUM>', the base <NUM> may include a circumferential lip <NUM> (<FIG>) extending downward therefrom which is sized and configured to cooperatively engage a portion of the modified guide tube <NUM>' in a manner that aligns the base <NUM> with the modified guide tube <NUM>'.

Referring again to <FIG> and <FIG>, as well as to <FIG>, <FIG>, each of the protruding members <NUM> includes a portion <NUM> that is configured to engage a corresponding portion of a guide funnel <NUM>' of thermal sleeve <NUM>. In the example of <FIG>, <FIG>, <FIG>, the portion <NUM> includes an outward facing surface <NUM> that is disposed at an angle that corresponds to the angle of an inner conical surface of the guide funnel <NUM>'. The portion <NUM> further includes a key <NUM> extending further outward from surface <NUM>. In the illustrated embodiment, the key <NUM> is in the form of a vertically oriented ridge-like element which is sized and configured to cooperatively engage a corresponding slot <NUM> (e.g., formed via EDM machining or other suitable method) defined in the guide funnel <NUM>'. The engagement between each key <NUM> and corresponding slot <NUM> resists, reduces, and/or prevents rotation of the thermal sleeve <NUM>, thus reducing wear otherwise resulting from rotation. <FIG> shows an example of a potential initial "raised up" orientation of the guide funnel <NUM>' on wear mitigation device <NUM>. Thermal sleeve <NUM> and guide funnel <NUM>' thereof will rotate as a result of coolant flow until oriented such that slots <NUM> align with keys <NUM>, thus causing guide funnel <NUM>' and thermal sleeve <NUM> to drop into the "fixed" position such as shown in <FIG>.

<FIG> depict a wear mitigation device <NUM>. The wear mitigation device <NUM> is similar to the device <NUM> previously discussed. The wear mitigation device <NUM> comprise a based <NUM>, formed as a circular ring that is configured to be coupled to the guide tube <NUM>', and a plurality of protruding members <NUM>, each extending upward from the base <NUM>, that are sized and configured to engage a guide funnel <NUM> of a thermal sleeve10, as will be discussed in greater detail below.

A portion <NUM> of each protruding member <NUM> of the device <NUM> is configured to engage a corresponding portion of a guide funnel <NUM> of the thermal sleeve <NUM> and includes an outward facing surface <NUM> that is disposed at an angle that corresponds to the angle of an inner conical surface of guide funnel <NUM>. As device <NUM> does not include any key, such as keys <NUM> of device <NUM>, the device <NUM> is configured to provide additional support surfaces to thermal sleeve <NUM> and guide funnel <NUM> thereof, which helps to reduce wear thereto, and reduce the rate at which thermal sleeve <NUM> drops, while resisting, reducing, and/or preventing rotation of thermal sleeve <NUM> and guide funnel <NUM> thereof (e.g., via increased frictional forces due to increased surface contact areas).

<FIG> depict a wear mitigation device <NUM>. The wear mitigation device <NUM> is similar to the wear mitigation devices <NUM> and <NUM>. The wear mitigation device <NUM> includes a base <NUM>, formed as a circular ring, that is configured to be coupled to the guide tube <NUM>', and a plurality of protruding members <NUM> extending upward from the base <NUM>. A portion <NUM> of each of the protruding members <NUM> of the device <NUM> is configured to engage a corresponding portion of a guide funnel <NUM> of the thermal sleeve <NUM>. Each portion <NUM> comprises an inward facing notch <NUM> that is sized and configured to engage a portion of the outer periphery of the guide funnel <NUM>. As the device <NUM> does not include any key, such as keys <NUM> of device <NUM>, the device <NUM>, similar to the device <NUM>, is configured to provide additional support surfaces to thermal sleeve <NUM> and guide funnel <NUM> thereof, which helps to reduce wear thereto, and reduces the rate at which the thermal sleeve <NUM> drops, while resisting, reducing, and/or preventing rotation of thermal sleeve <NUM> and the guide funnel <NUM> thereof (e.g., via increased frictional forces due to increased surface contact areas).

As an alternative to the previous devices <NUM>, <NUM> and <NUM> which utilized bases <NUM>, <NUM> and <NUM> that are bolted to a modified guide tube <NUM>', some example embodiments which instead clamp on to an unmodified guide tube <NUM> are discussed in greater detail below.

<FIG> depict a wear mitigation device <NUM>. The wear mitigation device <NUM> is similar to the wear mitigation devices <NUM>, <NUM>, and <NUM>. For example, the wear mitigation device includes a base <NUM> somewhat similar to that of devices <NUM>, <NUM> and <NUM>, previously discussed, except base <NUM> is not configured to be bolted to a guide tube <NUM> but instead is configured to be clamped thereto, as discussed in greater detail below.

Wear mitigation device <NUM> includes a plurality of protruding members <NUM> extending upward from base <NUM> that are identical to the plurality of protruding members <NUM> of wear mitigation device <NUM> discussed above (see <FIG> and <FIG>). The base <NUM> includes a bottom portion <NUM> that is configured to generally surround a top portion of a guide tube <NUM>. The bottom portion <NUM> includes a first arcuate arm member <NUM> that extends circumferentially in a first direction around a portion of guide tube <NUM> from a portion 422A of the bottom portion <NUM> to a distal end 450A, and a second arcuate arm member <NUM> that extends circumferentially in a second direction (opposite the first direction) around another portion of guide tube <NUM> from portion 422A of the bottom portion <NUM> to a distal end 452A that is disposed adjacent, but separate from, distal end 450A of the first arm member <NUM>. Each of the arm members <NUM> and <NUM> are elastically deformable such that the distal ends 450A and 452A thereof can be compressed together in a manner that clamps the base <NUM>, and thus wear mitigation device <NUM>, to the guide tube <NUM>. In the illustrated embodiment, the distal end 450A includes an aperture <NUM> (<FIG>) that is configured to allow a portion of a threaded bolt <NUM> to pass therethrough. The distal end 450A further comprises a crimpable collar <NUM> positioned about the aperture <NUM> that is configured to function in a manner similar to collar <NUM> previously discussed. Distal end 452A includes a threaded aperture <NUM> (<FIG>) that is configured to be threadingly engaged by the threaded bolt <NUM>. It is to be appreciated, that other suitable arrangements for tightening (or loosening) arm members <NUM> and <NUM> may be employed without varying from the scope of the present disclosure.

<FIG> depicts a wear mitigation device <NUM> that is similar to the wear mitigation devices <NUM>. For example, the wear mitigation device <NUM> includes a base <NUM> that is similar to that of device <NUM> except the base <NUM> comprises two separate clamping locations on opposite sides of the base <NUM> which are configured to clamp the wear mitigation device <NUM> to a guide tube <NUM>. More specifically, the base <NUM> includes a first set of first and second arcuate arm members <NUM> and <NUM> and a second set of first and second arcuate arm members <NUM> and <NUM>, with each set functioning similar to the arrangement of the first and second arcuate arm members <NUM> and <NUM> of device <NUM>, as discussed in greater detail below.

The wear mitigation device <NUM> includes a plurality of protruding members <NUM> extending upward from base <NUM> that are identical to the plurality of protruding members <NUM> of wear mitigation device <NUM> discussed above (see <FIG> and <FIG>). The base <NUM> includes a bottom portion <NUM> that is configured to generally surround a top portion of a guide tube <NUM>. The bottom portion <NUM> includes the pair of first arcuate arm members <NUM> which extend circumferentially around a first portion of guide tube <NUM> from a portion 522A of the bottom portion <NUM>. Each of the arcuate arm members <NUM> terminates at a distal end 550A. The bottom portion <NUM> further comprises the pair of second arcuate arm members <NUM> which extend circumferentially around a second portion (opposite the first portion) of the guide tube <NUM> from a portion 522B of the bottom portion <NUM>. Each of the second arcuate arm members <NUM> terminates at a distal end 552A that is disposed adjacent, but separate from, a corresponding distal end 550A of each of the first arm members <NUM>. Each of the arm members <NUM> and <NUM> are elastically deformable such that their respective distal ends 550A and 552A can be compressed together in a manner that clamps the base <NUM>, and thus wear mitigation device <NUM>, to the guide tube <NUM>.

Further to the above, the distal ends 550A include an aperture, similar to aperture <NUM> (<FIG>), that is configured to allow a portion of a threaded bolt <NUM> to pass therethrough. The distal ends 550A further comprises a crimpable collar <NUM> positioned about each aperture that is configured to function in a manner similar to collar <NUM> previously discussed. Further, the distal ends 552A include a threaded aperture, similar to threaded aperture <NUM> (<FIG>), that is configured to be threadingly engaged by the threaded bolts <NUM>. It is to be appreciated, that other suitable arrangements for tightening (or loosening) arm members <NUM> and <NUM> may be employed without varying from the scope of the present disclosure.

<FIG> illustrates another wear mitigation device <NUM> in accordance with yet another embodiment that is similar to the devices <NUM> and <NUM> previously discussed, except the base of the device <NUM> does not utilize any arm members to secure the device <NUM> to a guide tube <NUM>. More specifically, the base is formed as two separate portions 612A and 612B, which are coupled together via suitable adjustable fastening mechanisms <NUM>. In the illustrated example, the fastening mechanisms <NUM> are similar to the arrangement used to tighten distal ends 550A and 552A of devices <NUM> and <NUM> previously discussed, however, it is to be appreciated that other suitable fastening arrangements may be employed without varying from the scope of the present disclosure.

<FIG> depict a wear mitigation device <NUM> similar to devices <NUM> and <NUM> (<FIG>). For example, the wear mitigation device <NUM> comprises distal ends 750A and 752A of first and second arcuate arm members <NUM> and <NUM> similar to the devices <NUM> and <NUM>. Further, the wear mitigation device <NUM> comprises protruding members <NUM> which include outwardly facing surfaces <NUM> and keys <NUM>, as previously discussed. The wear mitigation device <NUM> comprises vertical coupling arrangements <NUM> configured to couple together the distal ends 750A and 752A of the first and second arcuate arm members <NUM> and <NUM>, as discussed in greater detail below.

Each vertical coupling arrangement <NUM> includes a clamping wedge <NUM>, a crimp cup <NUM>, a retention plate <NUM>, and a threaded bolt <NUM>. Referring primarily to <FIG>, the clamping wedge <NUM> is formed as a generally U-shaped member including a base <NUM> and a pair of vertically extending members <NUM> extending upward from the base <NUM>. Each of the vertically extending members <NUM> includes an inward facing surface <NUM> that is disposed at an outward angle such that a generally V-shaped groove <NUM> is defined between inward facing surfaces <NUM>. In the example illustrated, each of inward facing surfaces <NUM> are shaped as a portion of a cylinder, however it is to be appreciated that other arrangements may be employed without varying from the scope of the present disclosure. The base <NUM> includes a vertically oriented threaded hole <NUM> defined therein which is sized and configured to be threadingly engaged by a threaded portion of the bolt <NUM>.

Referring primarily to <FIG>, each of distal ends 750A and 752A of arcuate arm members <NUM> and <NUM> include an engagement surface <NUM> that is correspondingly shaped and positioned to engage with a corresponding one of the inward facing surfaces <NUM> of the clamping wedge <NUM>. Each of the distal ends 750A and 752A also include slots <NUM> which are engaged by cooperatively shaped protrusions <NUM> (<FIG>) that extend from a bottom surface of the crimp cup <NUM>. When assembled, each of distal ends 750A and 752A are positioned within the V-shaped groove <NUM> of the clamping wedges <NUM> such that engagement surfaces <NUM> are engaged with inward facing surfaces <NUM>. Apertures in the retention plate <NUM> are aligned with protrusions <NUM> extending above the vertically extending members <NUM> of the clamping wedge <NUM>. The retention plate <NUM> is then is coupled (e.g., via plug welds <NUM>) to the tops of the vertically extending members <NUM> of the clamping wedge <NUM> so as to capture the distal ends 750A and 752A within the V-shaped groove <NUM>. The bolt <NUM> is then inserted through the crimp cup <NUM>, passed between distal ends 750A and 752A and into threaded hole <NUM> in base <NUM> of clamping wedge <NUM>.

In use, the base of the wear mitigation device <NUM> is placed around the guide tube <NUM> and then the bolts are tightened to clamp the wear mitigation device <NUM> to the guide tube <NUM>. More specifically, when the bolt <NUM> is rotated in the clockwise direction, for example, the clamping wedge <NUM> will move upward (i.e., towards the crimp cup <NUM> of the bolt <NUM>). The inward facing surfaces <NUM> of the clamping wedge <NUM> will engage the engagement surfaces <NUM> of the distal ends 750A and 752A as the clamping wedge <NUM> moves upward. Thus, the distal ends 750A and 752A are clamped together, and thus, the wear mitigation device <NUM> is clamped around the guide tube <NUM> when the bolts <NUM> are rotated in a clockwise direction. Other embodiments are envisioned where the bolts <NUM> are rotated in a counter clockwise direction to clamp the wear mitigation device to the guide tube <NUM>.

It is to be appreciated that each vertical coupling arrangement <NUM> is designed so as to be fully assembled (i.e., as shown in <FIG>) in both a fully loosened positioning (i.e., when first and second arcuate arm members <NUM> and <NUM> are in a completely untightened positioning prior to install on a guide tube <NUM>) as well as in a fully tightened positioning (i.e., when first and second arcuate arm members <NUM> and <NUM> are tightened against a guide tube <NUM> (i.e., as shown in <FIG>) and provides for a vertically arranged bolt <NUM> that can be readily accessed during installation and/or removal of wear mitigation device <NUM> from a guide tube <NUM>.

Similar to the arrangement of <FIG>, <FIG> shows an example of a potential initial "raised up" orientation of guide funnel <NUM>' on wear mitigation device <NUM>. Thermal sleeve <NUM> and guide funnel <NUM>' thereof will rotate as a result of coolant flow until oriented such that the slots <NUM> align with the keys <NUM>, thus causing the guide funnel <NUM>' and the thermal sleeve <NUM> to drop into the "fixed" position such as shown in <FIG>. However, unlike the arrangement of <FIG> in which the outward facing surfaces <NUM> of device <NUM> were in contact with the inward facing conical surface <NUM>' of guide funnel <NUM>', the protruding members <NUM> of the device <NUM> are sized and configured such that the outward facing surfaces <NUM> thereof are spaced apart from the inward facing conical surface <NUM>' of guide funnel <NUM>' when guide funnel <NUM>' is in the "fixed" position, as shown in <FIG> and <FIG>. It is to be appreciated that such an arrangement of the device <NUM> serves to resist and/or reduce and/or prevent rotation of thermal sleeve <NUM> and guide funnel <NUM>' thereof, while not preventing axial and lateral (to an extent) movement of guide funnel <NUM>' and thermal sleeve <NUM>. Such an arrangement ensures that the flanged top of the thermal sleeve <NUM> remains in contact with the head penetration adapter <NUM>, thus preventing thermal continuity with the water inside of the CRDM latch assembly.

<FIG> depict a wear mitigation arrangement <NUM> comprising a base portion <NUM> having a base <NUM>, formed as a circular ring, that is configured to be coupled to a modified guide tube <NUM>' (as previously discussed, e.g., see <FIG>). The wear mitigation device <NUM> further comprises a plurality of inner protruding members <NUM>, and a plurality of outer protruding members <NUM>. Each inner protruding member <NUM> extends generally upward and inward from a radially inner portion of base <NUM> and is sized and configured to engage the inner conical surface of a guide funnel <NUM> of a thermal sleeve <NUM>. In the illustrated embodiment, the wear mitigation arrangement <NUM> includes four inner protruding members <NUM>, however, it is to be appreciated that the quantity of protruding members <NUM> may be varied without varying from the scope of this disclosure. Each outer protruding member <NUM> extends generally upward from a radially outward portion of base <NUM> and includes a ridge <NUM> facing outward and slightly upward. The wear mitigation arrangement <NUM> includes two outer protruding members <NUM>, however, it is to be appreciated that the quantity of outer protruding members <NUM> may be varied without varying from the scope of the present disclosure.

In order to couple the base <NUM> to the modified guide tube <NUM>', the base <NUM> includes a plurality of apertures <NUM> defined therethrough. Each aperture <NUM> is positioned so as to align with a corresponding one of the plurality of threaded blind holes <NUM> of modified guide tube <NUM>'(previously discussed) and to receive a threaded bolt (such as threaded bolt <NUM> of <FIG>) therethrough which threadingly engages the corresponding threaded blind hole <NUM> (e.g., similar to the arrangements shown in <FIG>). In the illustrated embodiment, each aperture is surrounded by a counter bore <NUM> in the base <NUM> to seat the head of the threaded bolt. However, other embodiments are envisioned where each aperture is surrounded by a collar that is crimpable, as previously discussed, to prevent the threaded bolts from loosening in service. In order to properly align base <NUM> with guide tube <NUM>', base <NUM> may include a circumferential lip <NUM> that extends downward therefrom which is sized and configured to cooperatively engage a portion of modified guide tube <NUM>' in a manner that aligns base <NUM> with modified guide tube <NUM>'.

Continuing to refer to <FIG>, the wear mitigation arrangement <NUM> further includes a cage <NUM> which is configured to be generally coupled to the guide funnel <NUM> just above the conical portion thereof and engage the base portion <NUM> in a manner that inhibits rotation of the guide funnel <NUM>. More specifically, the cage <NUM> includes an upper collar <NUM>, a lower ring <NUM>, and a plurality of connecting members <NUM> which span between the upper collar <NUM> and the lower ring <NUM> connecting the two upper collar <NUM> and lower ring <NUM> together. The lower ring <NUM> includes a plurality of circumferentially spaced notch portions <NUM> defined in the lower ring <NUM>. Each notch portion <NUM> is configured to engage one of the correspondingly positioned outer protruding member <NUM> of the base portion <NUM> in a manner that inhibits rotation of the guide funnel <NUM>. In the illustrated embodiment of <FIG> only two notch portions <NUM> are engaged by outer protruding members <NUM> of base portion <NUM>. However, other embodiments are envisioned with more or less than two notch portions <NUM> are engaged by more or less than two outer protruding members <NUM> (i.e., more or less than two outer protruding members <NUM> may be provided).

Further to the above, the cage <NUM> is formed as two separate portions 842A and 842B, which are coupled together via threaded bolts <NUM>. In the illustrated embodiment the bolts are positioned at the top and bottom of the cage <NUM> and on either side of the cage <NUM> (i.e., a total of four bolts <NUM> are provided). Other embodiments are envisioned with more or less than four bolts, for example. The cage <NUM> further comprises crimpable collars <NUM>, which function in the same manner as those previously discussed, extending from portion 842A of the cage <NUM>. The collars <NUM> surround the head portion of each bolt <NUM> when the bolts <NUM> are assembled to the cage <NUM>. It is to be appreciated that by being separable into two portions 842A and 842B, the cage <NUM> may readily be retrofitted to the guide funnel <NUM> on an installed thermal sleeve <NUM>. It is also to be appreciated that the cage <NUM> may be formed as a single unitary member or in more than two portions which may be coupled together without varying from the scope of the present disclosure.

<FIG> depict a wear mitigation device <NUM> comprising a base portion <NUM> having a base <NUM>, formed as a circular ring, that is configured to be coupled to a modified guide tube <NUM>' (such as previously discussed, e.g., see <FIG>). The wear mitigation device <NUM> further comprises a plurality of inner protruding members similar to the arrangement of <FIG>, which the inner conical surfaces of the guide funnel are configured to be seated on. Further, the device <NUM> comprises a plurality of protruding members <NUM> which protrude upward from the base portion <NUM> towards the guide funnel <NUM>. Each of the protruding members <NUM> includes a flat top surface <NUM>. In the illustrated embodiment, the wear mitigation device <NUM> includes two protruding members <NUM>, however, it is to be appreciated that the quantity of protruding members <NUM> may be varied without varying from the scope of the present disclosure.

in order to couple the base <NUM> to the modified guide tube <NUM>', the base <NUM> includes a plurality of apertures <NUM> defined therethrough. Each aperture <NUM> is positioned so as to align with a corresponding one of the plurality of threaded blind holes <NUM> of modified guide tube <NUM>'(previously discussed) and to receive a threaded bolt (such as threaded bolt <NUM> of <FIG>) therethrough which threadingly engages the corresponding threaded blind hole <NUM> (e.g., similar to the arrangements shown in <FIG>). In order to prevent each threaded bolt from loosening, the base <NUM> further includes a plurality of collars <NUM>, with each collar <NUM> being disposed about a corresponding one of apertures <NUM> and extending upward from the base <NUM>. Each collar <NUM> is deformable inward toward the head portion of each threaded bolt via a crimping tool (not shown) or other suitable mechanism in a manner such that collar <NUM> may be deformed against the head portion, thus preventing rotation of the threaded bolt engaged by the collar <NUM>. Additionally, the collar <NUM> prevents loose parts should the head portion separate from the remainder of the threaded bolt. In order to properly align the base <NUM> with guide tube <NUM>', the base <NUM> may include a circumferential lip <NUM> that extends downward therefrom which is sized and configured to cooperatively engage a portion of modified guide tube <NUM>' in a manner that aligns the base <NUM> with the modified guide tube <NUM>'.

Continuing to refer to <FIG>, the wear mitigation device <NUM> further includes a cage <NUM> which is configured to be generally coupled to the guide funnel <NUM> just above the conical portion thereof and engage the base portion <NUM> in a manner which inhibits rotation of the guide funnel <NUM>. More particularly, the cage <NUM> includes an upper collar <NUM>, a lower ring <NUM>, and a plurality of connecting members <NUM> which span between the upper collar <NUM> and the lower ring <NUM> connecting the upper collar <NUM> and lower ring <NUM> together. The lower ring <NUM> includes a plurality of circumferentially spaced notches or recessed portions <NUM> disposed facing radially outward from the lower ring <NUM>. Each recessed portion <NUM> is configured to engage a correspondingly positioned protruding member <NUM> of the base portion <NUM> in a manner that inhibits rotation of the guide funnel <NUM> about a central axis of the guide funnel <NUM>, while allowing for axial movement of the guide funnel <NUM>. In the example embodiment of <FIG>, only two recessed portions <NUM> are engaged by the protruding members <NUM> of the base portion <NUM>. However, other embodiments are envisioned with more or less than two recessed portions <NUM> engaged with protruding members <NUM> (i.e., more or less than two protruding members <NUM> may be provided).

As illustrated in <FIG>, the cage <NUM> is formed as two separate portions 942A and 942B, which are coupled together via threaded bolts <NUM>. The cage <NUM> further comprises crimpable collars <NUM>, which function in the same manner as those previously discussed, extending from portion 942A of the cage <NUM>. The collars <NUM> surround the head portion of each bolt <NUM> when the bolts <NUM> are assembled to the cage <NUM>. It is to be appreciated that by being separable into two portions 942A and 942B, the cage <NUM> may readily be retrofitted to the guide funnel <NUM> on an installed thermal sleeve <NUM>. It is also to be appreciated that the cage <NUM> may be formed as a single unitary member or in more than two portions which may be coupled together without varying from the scope of the present disclosure.

<FIG> depicts a wear mitigation device <NUM> comprising a base <NUM>, similar to base <NUM> previously discussed in regard to <FIG>, and a plurality of protruding members <NUM>. Each of the protruding members <NUM> extend upward from the base <NUM> and are sized and configured to engage a guide funnel <NUM>" of a thermal sleeve <NUM>, such as shown in <FIG>. In the illustrated embodiment, the wear mitigation device <NUM> includes four protruding members <NUM>, however, it is to be appreciated that the quantity of protruding members <NUM> may be varied without varying from the scope of the present disclosure.

In order to couple the base <NUM> to the modified guide tube <NUM>', the base <NUM> includes a plurality of apertures <NUM> defined therethrough. Each aperture <NUM> is positioned so as to align with a corresponding one of the plurality of threaded blind holes <NUM> of modified guide tube <NUM>' and to receive a threaded bolt <NUM> therethrough, such as shown in <FIG>, which threadingly engages the corresponding threaded blind hole <NUM>. In order to prevent each threaded bolt <NUM> from loosening, the base <NUM> further includes a plurality of collars <NUM>, with each collar <NUM> being disposed about a corresponding one of the apertures <NUM> and extending upward from base <NUM>. Each collar <NUM> is deformable inward toward the head portion of each threaded bolt <NUM> via a crimping tool (not shown) or other suitable mechanism in a manner such that collar <NUM> may be deformed against the head portion, thus preventing rotation of the threaded bolt <NUM> engaged by the collar <NUM>. Additionally, the collar <NUM> prevents loose parts should the head portion separate from the remainder of the threaded bolt <NUM>. In order to properly align the base <NUM> with the guide tube <NUM>', the base <NUM> may include a circumferential lip <NUM> that protrudes downward from the base <NUM> and which is sized and configured to cooperatively engage a portion of the modified guide tube <NUM>' in a manner that aligns the base <NUM> with the modified guide tube <NUM>'.

Each extending member <NUM> includes a portion <NUM> that is configured to engage a corresponding portion of guide funnel <NUM>" of the thermal sleeve <NUM>. Each portion <NUM> includes an outward facing surface <NUM> that is disposed at an angle that corresponds to the angle of an inner conical surface of guide funnel <NUM>". Two of the portions <NUM> further include a generally triangular-shaped key <NUM> extending further outward from the outward facing surface <NUM>. The triangular-shaped key <NUM> is sized and configured to cooperatively engage a corresponding triangular-shaped indent or notch <NUM> (e.g., formed via EDM machining or other suitable method) defined in guide funnel <NUM>". The engagement between each triangular-shaped key <NUM> and corresponding notch <NUM> resists, reduces, and/or prevents rotation of the thermal sleeve <NUM>, thus reducing wear otherwise resulting from rotation.

While specific embodiments of the invention have been described in detail, it will be appreciated by those skilled in the art that various modifications and alternatives to those details could be developed in light of the overall teachings of the disclosure and that selected elements of one or more of the example embodiments may be combined with one or more elements from other embodiments without varying from the scope of the disclosed concepts. Accordingly, the particular embodiments disclosed are meant to be illustrative only and not limiting as to the scope of the invention which is to be given the full breadth of the appended claims.

Those skilled in the art will recognize that, in general, terms used herein, and especially in the appended claims (e.g., bodies of the appended claims) are generally intended as "open" terms (e.g., the term "including" should be interpreted as "including but not limited to," the term "having" should be interpreted as "having at least," the term "includes" should be interpreted as "includes but is not limited to," etc.). It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles "a" or "an" limits any particular claim containing such introduced claim recitation to claims containing only one such recitation, even when the same claim includes the introductory phrases "one or more" or "at least one" and indefinite articles such as "a" or "an" (e.g., "a" and/or "an" should typically be interpreted to mean "at least one" or "one or more"); the same holds true for the use of definite articles used to introduce claim recitations.

In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of "two recitations," without other modifiers, typically means at least two recitations, or two or more recitations). Furthermore, in those instances where a convention analogous to "at least one of A, B, and C, etc." is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., "a system having at least one of A, B, and C" would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). In those instances where a convention analogous to "at least one of A, B, or C, etc." is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., "a system having at least one of A, B, or C" would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). It will be further understood by those within the art that typically a disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms unless context dictates otherwise. For example, the phrase "A or B" will be typically understood to include the possibilities of "A" or "B" or "A and B.

With respect to the appended claims, those skilled in the art will appreciate that recited operations therein may generally be performed in any order. Also, although various operational flow diagrams are presented in a sequence(s), it should be understood that the various operations may be performed in other orders than those which are illustrated, or may be performed concurrently. Examples of such alternate orderings may include overlapping, interleaved, interrupted, reordered, incremental, preparatory, supplemental, simultaneous, reverse, or other variant orderings, unless context dictates otherwise. Furthermore, terms like "responsive to," "related to," or other past-tense adjectives are generally not intended to exclude such variants, unless context dictates otherwise.

It is worthy to note that any reference to "one aspect," "an aspect," "an exemplification," "one exemplification," and the like means that a particular feature, structure, or characteristic described in connection with the aspect is included in at least one aspect. Thus, appearances of the phrases "in one aspect," "in an aspect," "in an exemplification," and "in one exemplification" in various places throughout the specification are not necessarily all referring to the same aspect. Furthermore, the particular features, structures or characteristics may be combined in any suitable manner in one or more aspects.

The terms "comprise" (and any form of comprise, such as "comprises" and "comprising"), "have" (and any form of have, such as "has" and "having"), "include" (and any form of include, such as "includes" and "including") and "contain" (and any form of contain, such as "contains" and "containing") are open-ended linking verbs. As a result, a system that "comprises," "has," "includes" or "contains" one or more elements possesses those one or more elements, but is not limited to possessing only those one or more elements. Likewise, an element of a system, device, or apparatus that "comprises," "has," "includes" or "contains" one or more features possesses those one or more features, but is not limited to possessing only those one or more features.

Claim 1:
A device (<NUM>) for resisting rotation of a thermal sleeve (<NUM>) about a central axis (<NUM>) thereof relative to a head penetration adapter (<NUM>) in a nuclear reactor (<NUM>), wherein the device comprises:
a first structure (<NUM>) and a second structure (<NUM>), wherein the first structure (<NUM>) and the second structure (<NUM>) are configured to be operably engaged to resist rotation of the thermal sleeve (<NUM>) about the central axis relative to the head penetration adapter (<NUM>) while allowing axial movement of the thermal sleeve (<NUM>) relative to the head penetration adapter (<NUM>),
characterized in that
the first structure comprises a first ring (<NUM>) configured to be coupled to the thermal sleeve (<NUM>), wherein the first ring comprises a plurality of rod members (<NUM>) extending therefrom, wherein each rod member extends along a rod axis (RA) that is parallel to the central axis of the thermal sleeve (<NUM>) when the first structure is coupled to the thermal sleeve (<NUM>); and
the second structure comprises a second ring (<NUM>) configured to be coupled to the head penetration adapter (<NUM>), wherein the second ring comprises a plurality of thru-holes (<NUM>) formed therein, wherein each thru-hole defines a thru-hole axis (THA) that is parallel to the central axis when the second ring is coupled to the head penetration adapter (<NUM>), and wherein each rod member of the first ring (<NUM>) is configured to slidingly engage a corresponding thru-hole of the second ring (<NUM>).