Patent Description:
A gas turbine engine includes various fluid systems such as a lubrication system. The lubrication system may include a lubricant reservoir within a case. The case may include a drain orifice in its sidewall for draining lubricant from the lubricant reservoir for maintenance, inspection, etc. The drain orifice may be plugged with an orifice plug such as a threaded fastener; e.g., a bolt. While known orifice plugs have various advantages, there is still room in the art for improvement.

<CIT> discloses a fluid level gauge having a swivel blade.

According to an aspect of the present invention, an assembly is provided for a fluid system in accordance with claim <NUM>.

The following optional features may be applied to the above aspect.

The wrenching feature may be configured with one or more flats.

The fluid system assembly may also include an annular seal element configured with the protrusion within the internal bore. The annular seal element may seal a gap between the protrusion and the fluid conduit.

The protrusion may include a cylindrical surface that extends axially along at least seven-tenths of a length of the protrusion from the head to the distal end of the plug.

The fluid system assembly may also include an annular seal element within the internal bore. The annular seal element may seal a gap between the protrusion and the fluid conduit.

The annular seal element may be configured as or otherwise include an O-ring.

The annular seal element may be seated in a groove in the protrusion.

At least a portion (or an entirety) of the protrusion may have a polygonal cross-sectional geometry.

The polygonal cross-sectional geometry may be a rectangular cross-sectional geometry.

The plug may also include a flexible wire bristle pack arranged within the internal bore and attached to the protrusion.

At least a portion (or an entirety) of the axial centerline may be non-straight. The protrusion may be configured from or otherwise include flexible material.

The fluid system assembly may also include a nut securing the plug to the fluid conduit. The head may project axially through an aperture in the nut towards the wrenching feature.

The head may be seated against the fluid conduit at a cone seal interface.

The fluid system assembly may also include a nut securing the plug to the fluid conduit.

The nut may include a sleeve and an inner rim. The sleeve may be mated with the fluid conduit at a threaded interface. The head may be sandwiched axially between the inner rim and an end of the fluid conduit.

<FIG> illustrates an assembly <NUM> for a fluid system. This fluid system may be configured as a lubrication system included in or otherwise configured with, for example, a piece of rotational equipment such as a gas turbine engine. The present disclosure, however, is not limited to such an exemplary fluid system. The fluid system, for example, may also or alternatively be configured as a cooling system, a heating system, a fuel system and/or a fluid actuated system (e.g., hydraulic system) in the gas turbine engine. Furthermore, the present disclosure is not limited to gas turbine engine nor rotational equipment applications. The fluid system, for example, may alternatively be included in or otherwise configured with a wind turbine, a water turbine, a transmission or any other apparatus with a pluggable fluid passage (e.g., a reservoir, a heat exchanger, etc.).

The fluid system assembly <NUM> includes a fluid conduit <NUM> and a fluid conduit plug assembly <NUM>. The fluid system assembly <NUM> of <FIG> also includes a fluid system structure <NUM> (e.g., a case) with an internal fluid reservoir <NUM>; e.g., a lubricant reservoir, etc..

The fluid conduit <NUM> may be configured as a drain extension and/or an extension spout for the fluid reservoir <NUM>. The fluid conduit <NUM> of <FIG>, for example, is configured to functionally relocate an aperture <NUM> (e.g., a drain orifice) in a sidewall <NUM> of the fluid system structure <NUM> from a first location <NUM> to a second location <NUM>; e.g., a more accessible location.

Referring to <FIG>, the fluid conduit <NUM> of is configured as a length of (e.g., rigid, non-flexible) pipe and/or tubing. The fluid conduit <NUM> includes a tubular sidewall <NUM> that extends circumferentially about (e.g., completely around) an axial centerline <NUM>. The fluid conduit <NUM> and its tubular sidewall <NUM> extend axially along the axial centerline <NUM> from a first (e.g., upstream and/or gravitationally upper) end <NUM> of the fluid conduit <NUM> to a second (e.g., downstream and/or gravitationally lower) end <NUM> of the fluid conduit <NUM>.

The fluid conduit <NUM> and its axial centerline <NUM> may be straight or non-straight (e.g., bent, curved, etc.) depending upon, for example, the specific fluid system application and/or the aperture relocation requirements. The fluid conduit <NUM> of <FIG>, in particular, is a non-straight conduit. This fluid conduit <NUM> includes a first (e.g., upstream and/or gravitationally upper) conduit portion <NUM>, a second (e.g., downstream and/or gravitationally lower) conduit portion <NUM> and an intermediate (e.g., coupling, elbow) conduit portion <NUM>. The intermediate conduit portion <NUM> is axially between and is connected to (e.g., formed integral with) the first conduit portion <NUM> and the second conduit portion <NUM>. The first conduit portion <NUM> is angularly offset from the second conduit portion <NUM> by an included angle <NUM>; e.g., an obtuse angle, a right angle or an acute angle. Each of the conduit portions <NUM> and <NUM> may be straight. Thus, a portion of the axial centerline <NUM> within each conduit portion <NUM>, <NUM> may be straight.

The first conduit portion <NUM> of <FIG> includes one or more external threads <NUM> and <NUM>. The first external thread <NUM> is arranged at (e.g., on, adjacent or proximate) the conduit first end <NUM>. The second external thread <NUM> is arranged axially next to (e.g., but spaced axially from) the first external thread <NUM>.

Referring to <FIG>, the first external thread <NUM> is configured to mate with an internal thread <NUM> of the fluid system structure <NUM> within the sidewall aperture <NUM>. The first conduit portion <NUM> may thereby be thread (e.g., partially) into the sidewall aperture <NUM> to attach (e.g., mechanically fasten) the fluid conduit <NUM> to the fluid system structure <NUM> and its sidewall <NUM>.

The second external thread <NUM> is configured to mate with an internal thread <NUM> of a jam nut <NUM>. This jam nut <NUM> may be used to rotationally lock the fluid conduit <NUM> relative to the fluid system structure <NUM> and its sidewall <NUM>. The jam nut <NUM> may thereby prevent (e.g., unintentional) decoupling of the fluid conduit <NUM> from the fluid system structure <NUM> during fluid system operation.

Referring to <FIG>, the second conduit portion <NUM> includes a fluid coupling portion <NUM> (e.g., a nipple) and an external thread <NUM>. The fluid coupling portion <NUM> is arranged at (e.g., on, adjacent or proximate) the conduit second end <NUM>. The fluid coupling portion <NUM> of <FIG> is configured with an annular tapered (e.g., a frustoconical) surface <NUM>. This tapered surface <NUM> tapers radially inward towards the axial centerline <NUM> as the fluid coupling portion <NUM> extends axially towards (or to) the conduit second end <NUM>. The external thread <NUM> is arranged axially next to, but may be spaced axially from, the fluid coupling portion <NUM>.

The second conduit portion <NUM> of <FIG> may also include a wrenching feature <NUM>. This wrenching feature <NUM> may be configured as a flange <NUM> (e.g., an annular rim) which extends circumferentially about (e.g., completely around) a base <NUM> of the fluid conduit <NUM>. The flange <NUM> is connected to (e.g., formed integral with) and projects radially out from the fluid conduit base <NUM> to a distal outer periphery of the flange <NUM>. The distal outer periphery may be formed by one or more flats <NUM>; e.g., flat, planar surfaces. The flats <NUM> of <FIG> are arranged circumferentially about the axial centerline <NUM> to provide the flange <NUM> with a polygonal (e.g., a hexagonal) cross-sectional geometry when viewed, for example, in a plane perpendicular to the axial centerline <NUM>.

Referring to <FIG>, the fluid conduit <NUM> is configured with an internal bore <NUM>. This internal bore <NUM> forms a fluid passage through the fluid conduit <NUM>. In particular, the internal bore <NUM> extends axially along the axial centerline <NUM> through the fluid conduit <NUM> from the conduit first end <NUM> to the conduit second end <NUM>. At least a portion or an entirety of the internal bore <NUM> may be configured as a smooth-walled (e.g., non-threaded, non-textured, etc.) internal bore. The internal bore <NUM> of <FIG>, for example, is formed by one or more smooth surfaces; e.g., surfaces without threads. The smooth surfaces of <FIG> include first and second smooth cylindrical surfaces 80A-B, a smooth frustoconical surface 80C and a partially-conical surface 80D. The present disclosure, however, is not limited to such an exemplary smooth-walled internal bore. For example, in other embodiments, at least an end portion of the internal bore <NUM> may be formed with an internal thread for a threaded coupling; thus, non-smooth-walled.

Referring to <FIG>, the plug assembly <NUM> includes a fluid conduit plug <NUM> and a fluid conduit nut <NUM>. Referring to <FIG>, the plug <NUM> extends axially along (e.g., a straight portion of) the axial centerline <NUM> between and to a distal first (e.g., upstream and/or gravitationally upper) end <NUM> of the plug <NUM> and a second (e.g., downstream and/or gravitationally lower) end <NUM> of the plug <NUM>. The plug <NUM> of <FIG> includes a (e.g., non-threaded) plug protrusion <NUM> and a plug head <NUM>.

The protrusion <NUM> is configured as a conduit bore filling (e.g., plugging) member of the plug <NUM>. The protrusion <NUM> of <FIG>, for example, is configured as a shaft (e.g., non-threaded, cylindrical rod) of the plug <NUM> with an (e.g., cylindrical) outer surface <NUM>. The protrusion <NUM> is connected (e.g., formed integral with) the head <NUM>. The protrusion <NUM> projects axially along the axial centerline <NUM> out from the head <NUM> to a distal end of the protrusion <NUM>, which is also the distal first end <NUM> of the plug <NUM>.

Referring to <FIG>, the protrusion <NUM> and its outer surface <NUM> may have a circular cross-sectional geometry when viewed, for example, in a plane perpendicular to the axial centerline <NUM>. The protrusion <NUM> of <FIG> has a lateral width <NUM>; e.g., a diameter. This protrusion lateral width <NUM> may remain uniform (e.g., constant) along an entirety or at least a substantial portion (e.g., at least <NUM>-<NUM>%) of an axial length <NUM> of the protrusion <NUM>. The protrusion lateral width <NUM> is sized such that the protrusion <NUM> is operable to slide into / slide within and at least partially (or completely) fill at least a portion of the internal bore <NUM> as described below; e.g., see <FIG>. The protrusion lateral width <NUM>, for example, may be slightly less than a lateral width <NUM> (e.g., diameter) of the internal bore <NUM> (see <FIG>), but at least seventy, eighty or ninety percent (<NUM>, <NUM> or <NUM>%) of the internal bore lateral width <NUM>.

The head <NUM> is configured as a conduit orifice covering (e.g., sealing) member of the plug <NUM>. The head <NUM> of <FIG>, for example, includes a head base <NUM> and a tubular head flange <NUM>. The head base <NUM> is arranged at (e.g., on, adjacent or proximate) the plug second end <NUM>. The head base <NUM> of <FIG>, for example, extends axially along the axial centerline <NUM> from the plug second end <NUM> to the protrusion <NUM> and the head flange <NUM>. The head base <NUM> extends radially outward to an (e.g., cylindrical) outer surface <NUM>.

The head flange <NUM> is connected to (e.g., formed integral with) the head base <NUM>. The head flange <NUM> extends axially along the axial centerline <NUM> from the head base <NUM> to a distal end <NUM> of the head <NUM>. The head flange <NUM> extends circumferentially about (e.g., completely around) the axial centerline <NUM>. The head flange <NUM> may thereby circumscribe and axially overlap a base portion of the protrusion <NUM>. The head flange <NUM> extends radially from a (e.g., cylindrical) radial inner surface <NUM> of the head flange <NUM> to a (e.g., cylindrical) radial outer surface <NUM> of the head flange <NUM>. An annular (e.g., flat) shelf surface <NUM> of the head <NUM> extends radially between and to, and is angularly offset from (e.g., perpendicular to) the base outer surface <NUM> and the flange outer surface <NUM>.

The head flange <NUM> includes an annular tapered (e.g., a frustoconical) surface <NUM>. This tapered surface <NUM> tapers radially inward towards the axial centerline <NUM> (e.g., to the flange inner surface <NUM>) as the head flange <NUM> extends axially away from the head distal end <NUM>.

Referring to <FIG>, the nut <NUM> includes a tubular nut sleeve <NUM> and an annular nut rim <NUM>; e.g., an inner rim. The nut <NUM> and its sleeve <NUM> extend axially along the axial centerline <NUM> between and to a first end <NUM> of the nut <NUM> and a second end <NUM> of the nut <NUM>. The nut <NUM> and each of its components <NUM> and <NUM> extend circumferentially about (e.g., completely around) the axial centerline <NUM>.

The nut sleeve <NUM> extends radially between and to a radial inner side <NUM> and a radial outer side <NUM>. The nut sleeve <NUM> includes a (e.g., smooth, cylindrical) radial inner surface <NUM> at the sleeve inner side <NUM>. The nut sleeve <NUM> also includes an internal thread <NUM> at the sleeve inner side <NUM> and the nut first end <NUM>. The nut sleeve <NUM> includes a (e.g., smooth, cylindrical) radial inner surface <NUM> at the sleeve outer side <NUM> and the nut first end <NUM>. The nut sleeve <NUM> also includes a wrenching feature <NUM> at the sleeve outer side <NUM> and the nut second end <NUM>. An outer periphery of the wrenching feature <NUM> may be formed by one or more flats <NUM>; e.g., flat, planar surfaces. The flats <NUM> of <FIG> are arranged circumferentially about the axial centerline <NUM> to provide the wrenching feature <NUM> with a polygonal (e.g., a hexagonal) cross-sectional geometry when viewed, for example, in a plane perpendicular to the axial centerline <NUM>.

The nut rim <NUM> of <FIG> is connected to (e.g., formed integral with) the nut sleeve <NUM> at (e.g., on, adjacent or proximate) the nut second end <NUM>. The nut rim <NUM> projects radially inward from the nut sleeve <NUM> to an annular distal end surface <NUM>. The nut rim <NUM> includes an annular shelf surface <NUM>, which extends radially between and is angularly offset from (e.g., perpendicular to) the rim end surface <NUM> and the base inner surface <NUM>.

Referring to <FIG>, during fluid system operation, the plug assembly <NUM> closes the internal bore <NUM> such that fluid (e.g., lubricant) cannot drain from the fluid reservoir <NUM> through the fluid conduit <NUM>. In particular, the plug <NUM> and the nut <NUM> are mated with the fluid conduit <NUM>. The protrusion <NUM>, for example, is slid axially into the internal bore <NUM> until the head flange <NUM> engages (e.g., contacts) the fluid conduit <NUM> at its second end <NUM>. The annular tapered surface <NUM> of the plug <NUM> may thereby engage (e.g., contact) the annular tapered surface <NUM> of the fluid conduit <NUM>. The nut <NUM> is mounted onto the head <NUM> and the fluid conduit <NUM>. The head base <NUM>, for example, projects through a bore of the nut <NUM> and out an opening formed by the nut rim <NUM>. The internal thread <NUM> is mated with the external thread <NUM> such that the nut <NUM> may be threaded onto the fluid conduit <NUM>. The nut <NUM> is tightened onto the fluid conduit <NUM> until the head flange <NUM> is sandwiched axially between the nut rim <NUM> and the fluid conduit <NUM>. In particular, the shelf surface <NUM> is pressed axially against the shelf surface <NUM>. The tapered surface <NUM> is seated and pressed against the tapered surface <NUM>, which thereby provides a cone seal interface between the plug <NUM> and the fluid conduit <NUM>. The head <NUM> may thereby close off and seal an opening (e.g., a drain orifice) in the conduit second end <NUM> to the internal bore <NUM>.

Under certain conditions, the fluid conduit <NUM> and thereby the fluid within the fluid conduit <NUM> may be subject to relatively high temperatures during fluid system operation. For example, where the fluid system is included in a gas turbine engine or another rotational equipment application, gas (e.g., air) in a plenum <NUM> surrounding the fluid conduit <NUM> and adjacent the fluid system structure <NUM> may be heated to an elevated temperature. When the fluid within the fluid conduit <NUM> is heated to or above a certain temperature, some of that fluid may partially solidify (e.g., coke) and leave particulate deposits on the fluid conduit <NUM> within the internal bore <NUM>.

To reduce or prevent accumulation of deposits within at least a portion of the fluid conduit <NUM>, the protrusion <NUM> projects axially (e.g., partially) into the internal bore <NUM> to the distal plug first end <NUM>. In the embodiment of <FIG>, the plug first end <NUM> is located at the intermediate conduit portion <NUM>. Therefore, in addition to closing the opening to the internal bore <NUM>, the plug <NUM> also displaces volume within the internal bore <NUM> via the protrusion <NUM>. By displacing volume within the internal bore <NUM>, the protrusion <NUM> reduces the amount of fluid (e.g., lubricant) that can remain within the internal bore <NUM> during fluid system operation. The plug <NUM> of <FIG>, for example, may prevent any or a significant amount of the fluid from being within at least a portion of the internal bore <NUM>; e.g., a portion of the internal bore <NUM> within the second conduit portion <NUM>. The plug assembly <NUM> of <FIG> is therefore operable to reduce fluid deposits from accumulating within the internal bore <NUM> during fluid system operation.

In some embodiments, referring to <FIG>, the protrusion outer surface <NUM> may extend axially (e.g., uninterrupted) along at least one-half of the protrusion axial length <NUM>; e.g., at least six-tenths, seven-tenths, eight-tenths, nine-tenths or an entirety of the protrusion axial length <NUM>. The protrusion outer surface <NUM> of <FIG>, for example, extends axially (e.g., uninterrupted) along the entirety of the protrusion axial length <NUM>. The protrusion outer surface <NUM>, however, may extend axially (e.g., uninterrupted) along at least eight-tenths or nine-tenths of the protrusion <NUM> where, for example, the protrusion is chamfered at the first end <NUM> (e.g., see chamfered end of <FIG>). The present disclosure, of course, is not limited to the foregoing exemplary outer surface axial dimensions.

In some embodiments, referring to <FIG>, the plug assembly <NUM> may also include at least one (or only one) annular seal element <NUM> such as, but not limited to, an O-ring. The seal element <NUM> may be seated partially in an annular groove in the protrusion <NUM>. The seal element <NUM> is arranged within the internal bore <NUM> with the protrusion <NUM>, and is configured to sealingly engage (e.g., be compressed radially between and/or contact) the protrusion <NUM> and the fluid conduit <NUM>. The seal element <NUM> may thereby seal a (e.g., annular) gap between the protrusion <NUM> and the fluid conduit <NUM>. Such a seal interface may further reduce the amount of fluid that can reside within the internal bore <NUM>, particularly within the second conduit portion <NUM> downstream of the seal element <NUM>. In addition, the seal element <NUM> may also prevent or reduce fluid leakage out from the conduit opening after the nut <NUM> is removed and the head <NUM> is initially moved away from the fluid conduit <NUM>. Maintenance personal may therefore have more time to position a catch basis, a funnel and/or another device at the conduit second end <NUM> for catching the fluid which flows through the conduit opening after removal of the plug <NUM>.

In some embodiments, referring to <FIG>, the seal element <NUM> may be positioned at or near the plug first end <NUM>. The present disclosure, however, is not limited to such an exemplary seal element position.

Referring to <FIG>, the plug <NUM> includes a wrenching feature <NUM>. This wrenching feature <NUM> is configured as part of / integrated into the head <NUM> and, optionally more particularly, the head base <NUM>. With this configuration, the wrenching feature <NUM> may be exposed even when the nut <NUM>, for example, is still holding / securing the plug <NUM> with the fluid conduit <NUM> (see <FIG>). The wrenching feature <NUM> may thereby be engaged by a tool (e.g., a wrench, pliers, etc.), and the plug <NUM> may be rotated about its axial centerline <NUM> before removal. Such rotation may serve to break deposits which may temporarily bond the protrusion <NUM> to the fluid conduit <NUM> (see <FIG>).

The wrenching feature <NUM> of <FIG> includes one or more flats <NUM>; e.g., flat, planar surfaces. Referring to <FIG>, the flats <NUM> are arranged on opposing sides of the head base <NUM>. An arcuate portion <NUM> of the outer surface <NUM> is laterally between and extends circumferentially between respective sides of the flats <NUM>. The present disclosure, however, is not limited to such an exemplary wrenching feature. For example, in other embodiments, the wrenching feature <NUM> may provide the outer periphery of the plug <NUM> with a polygonal (e.g., hexagonal) cross-sectional geometry or otherwise.

In the claimed embodiment, referring to <FIG>, at least a portion of or the entire axial length <NUM> of the protrusion <NUM> is twisted about the axial centerline <NUM>. The protrusion <NUM>, for example, may have an auger, drill bit, spiral and/or helical configuration. A direction of the twist in the protrusion <NUM> may be opposite a direction of rotation of the internal thread <NUM> (see <FIG>). Of course, the present disclosure is not limited to such an exemplary arrangement. For example, in other embodiments, the direction of the twist in the protrusion <NUM> may be the same as the direction of rotation of the internal thread <NUM> (see <FIG>).

With the twisted configuration of <FIG>, one or more of the edges <NUM> of the protrusion <NUM> may each function as a scrapper blade within the internal bore <NUM> (see <FIG>). The protrusion edge(s) <NUM>, for example, may be moved within the fluid conduit <NUM> and scrape off any fluid deposits within the internal bore <NUM> (see <FIG>). For example, before removing the protrusion <NUM> from the internal bore <NUM> (see <FIG>), the plug <NUM> and, thus, the protrusion <NUM> may be twisted (e.g., at least <NUM>° about the axial centerline <NUM>) using the wrenching feature <NUM> such that the edge(s) <NUM> scrape along (e.g., a circumferential entirety of; <NUM>° around) respective interior surface(s) forming the internal bore <NUM> (see <FIG>). Such scraping may dislodge / scrape off fluid particulates (e.g., coked lubricant) from the interior bore surfaces. This twisting may also or alternatively be performed while the protrusion <NUM> is being removed (e.g., slide out axially) from the internal bore <NUM> (see <FIG>). Of course, in still other embodiments, the plug <NUM> and its protrusion <NUM> may be removed from the internal bore <NUM> (see <FIG>) without any plug twisting movement.

In some embodiments, at least a portion or the entire axial length <NUM> of the protrusion <NUM> may have a polygonal cross-sectional geometry when viewed, for example, in a plane perpendicular to the axial centerline <NUM>. The protrusion <NUM> of <FIG>, for example, has a rectangular cross-sectional geometry. This protrusion <NUM> may be constructed from or otherwise include a length of flexible metal sheet material (e.g., thin steel plate). The protrusion <NUM> and its rectangular cross-sectional geometry of <FIG> are twisted at least one-hundred and eighty degrees (<NUM>°) about the axial centerline <NUM> along a select portion of the axial length <NUM> of the protrusion <NUM>.

In some embodiments, referring to <FIG>, at least a portion or the entire axial length <NUM> of the protrusion <NUM> may be constructed from flexible material. An example of such flexible material is ductile, pliable steel wire. Another example of the flexible material is silicon. With such a construction, at least a portion of the protrusion <NUM> may deform (e.g., bend) so as to pass through the intermediate conduit portion <NUM> and into the first conduit portion <NUM>. The present disclosure, of course, is not limited to the foregoing exemplary flexible materials.

In some embodiments, the protrusion <NUM> may include one or more annular members <NUM>. The protrusion <NUM> of <FIG>, for example, is configured with one or more flexible wire bristle packs <NUM>. These bristle packs <NUM> are arranged along the axial length <NUM> of the protrusion <NUM>. Each of the bristle packs <NUM> is configured to radially engage the fluid conduit <NUM>. The bristle packs <NUM> may thereby scrape off fluid deposits when the protrusion <NUM> is removed from the internal bore <NUM>.

Any one of the plug assemblies <NUM> / plugs <NUM> disclosed herein may be configured with a wrenching feature such as, but not limited to, the wrenching feature <NUM> of <FIG>. The plug assembly <NUM> and its plug of <FIG>, for example, may be configured with one or more wrenching feature flats as described above with respect to <FIG>. Of course, in other embodiments, any one or more of the plug assemblies <NUM> / plugs <NUM> may be configured without a wrenching feature.

The fluid system assembly <NUM> may be included as part of and/or otherwise configured with various pieces of equipment, including various types and configurations of rotational equipment. The fluid system assembly <NUM>, for example, may be included as part of and/or otherwise configured with a gas turbine engine for an aircraft propulsion system. <FIG> illustrates an exemplary embodiment of such a gas turbine engine <NUM>, which is configured as a geared turbofan gas turbine engine.

The turbine engine <NUM> of <FIG> extends along an axis <NUM> between an upstream airflow inlet <NUM> and a downstream airflow exhaust <NUM>. The turbine engine <NUM> includes a fan section <NUM>, a compressor section <NUM>, a combustor section <NUM> and a turbine section <NUM>. The compressor section <NUM> includes a low pressure compressor (LPC) section 169A and a high pressure compressor (HPC) section 169B. The turbine section <NUM> includes a high pressure turbine (HPT) section 171A and a low pressure turbine (LPT) section 171B.

The engine sections <NUM>-171B are arranged sequentially along the axis <NUM> within an engine housing <NUM>. This engine housing <NUM> includes an inner case <NUM> (e.g., a core case) and an outer case <NUM> (e.g., a fan case). The inner case <NUM> may house one or more of the engine sections 169A-171B; e.g., an engine core. The outer case <NUM> may house at least the fan section <NUM>. The engine housing <NUM> and, more particularly for example, the inner case <NUM> may include or otherwise be configured with the fluid system structure <NUM> of <FIG>. Alternatively, the fluid system structure <NUM> of <FIG> may be configured as a part of another apparatus within the turbine engine <NUM>. The fluid system structure <NUM> of <FIG>, for example, may be configured as a case / housing for a gear train <NUM> and/or a bearing <NUM> in the turbine engine <NUM> of <FIG>.

Each of the engine sections <NUM>, 169A, 169B, 171A and 171B of <FIG> includes a respective rotor <NUM>-<NUM>. Each of these rotors <NUM>-<NUM> includes a plurality of rotor blades arranged circumferentially around and connected to one or more respective rotor disks. The rotor blades, for example, may be formed integral with or mechanically fastened, welded, brazed, adhered and/or otherwise attached to the respective rotor disk(s).

The fan rotor <NUM> is connected to the gear train <NUM>, for example, through a fan shaft <NUM>. The gear train <NUM> and the LPC rotor <NUM> are connected to and driven by the LPT rotor <NUM> through a low speed shaft <NUM>. The HPC rotor <NUM> is connected to and driven by the HPT rotor <NUM> through a high speed shaft <NUM>. The shafts <NUM>-<NUM> are rotatably supported by a plurality of the bearings <NUM>. Each of these bearings <NUM> is connected to the engine housing <NUM> by at least one stationary structure such as, for example, an annular support strut.

During operation, air enters the turbine engine <NUM> through the airflow inlet <NUM>. This air is directed through the fan section <NUM> and into a core gas path <NUM> and a bypass gas path <NUM>. The core gas path <NUM> extends sequentially through the engine sections 169A-171B. The bypass gas path <NUM> extends away from the fan section <NUM> through a bypass duct, which circumscribes and bypasses the engine core. The air within the core gas path <NUM> may be referred to as "core air". The air within the bypass gas path <NUM> may be referred to as "bypass air.

The fluid system assembly <NUM> may be included in various aircraft and industrial turbine engines other than the one described above as well as in other types of rotational and non-rotational equipment. The fluid system assembly <NUM>, for example, may be included in a geared turbine engine where a gear train connects one or more shafts to one or more rotors in a fan section, a compressor section and/or any other engine section. Alternatively, the fluid system assembly <NUM> may be included in a turbine engine configured without a gear train. The fluid system assembly <NUM> may be included in a geared or non-geared turbine engine configured with a single spool, with two spools (e.g., see <FIG>), or with more than two spools. The turbine engine <NUM> may be configured as a turbofan engine, a turbojet engine, a propfan engine, a pusher fan engine or any other type of turbine engine. The present disclosure therefore is not limited to any particular types or configurations of turbine engine. Furthermore, the fluid system assembly <NUM> of the present disclosure may also be utilized for non-turbine engine applications. The fluid system assembly <NUM>, for example, may be utilized for any application where it is desirable to functional relocate a closable fluid orifice and/or plug an internal bore <NUM>.

Claim 1:
An assembly (<NUM>) for a fluid system, comprising:
a fluid conduit (<NUM>) with an internal bore (<NUM>), the internal bore (<NUM>) comprising a smooth-walled internal bore (<NUM>); and
a plug (<NUM>) including a protrusion (<NUM>) and a head (<NUM>), the protrusion (<NUM>) connected to the head (<NUM>) and projecting axially along an axial centerline (<NUM>) partially into the smooth-walled internal bore (<NUM>) to a distal end (<NUM>) of the plug (<NUM>), and the head (<NUM>) seated against the fluid conduit (<NUM>) and sealing an opening in the fluid conduit (<NUM>) to the internal bore (<NUM>),
wherein at least a portion of the protrusion (<NUM>) is twisted about the axial centerline (<NUM>),
characterised in that:
the head (<NUM>) comprises a wrenching feature (<NUM>).