Abstract:
A bladder assembly including a body, a bladder received in the body, the bladder defining an internal volume and including an annular sealing bead, the sealing bead defining an opening into the internal volume, and a sealing member including a shaft having a first end and a second end, and an engagement portion connected proximate the second end, the sealing member being partially received within the internal volume and being moveable between at least a first position, wherein the engagement portion is spaced from the sealing bead, and a second position, wherein the sealing bead is compressed between the engagement portion and the body.

Description:
FIELD 
       [0001]    This application relates to bladder sealing and, more particularly, to apparatus and methods for sealing a bladder for pressure testing. 
       BACKGROUND 
       [0002]    Various parts, such as composite parts, are subjected to high pressures while in use. Therefore, during the research and development phase, such parts are vigorously tested to ensure they are capable of withstanding high pressures for prolonged periods of time. Indeed, parts are often tested at pressures that are significantly higher than the pressures at which the parts were design to operate. 
         [0003]    Pressure testing, particularly high pressure testing, typically involves introducing a pressurized fluid, such as a gas or hydraulic fluid, to act on the part under test. Depending on the structure and composition of the part, it may be difficult to maintain the pressures required to run the test to completion. For example, parts with holes and/or parts constructed from porous materials may be difficult to subject to high pressures. 
         [0004]    Thus, bladders have been used in pressure testing. For example, a bladder may be inserted into a bore within the part under test and then the bladder may be pressurized. The bladder contains the pressurized fluid, thereby facilitating pressure testing of various parts, including parts with holes. 
         [0005]    Unfortunately, using bladders for pressure testing introduces an additional step, which often complicates the test and increases costs. For example, it often becomes quite difficult to obtain a proper, pressure-tight seal in the bladder, particularly when the bladder is being used for high pressure testing. 
         [0006]    Accordingly, those skilled in the art continue with research and development efforts in the field of pressure testing. 
       SUMMARY 
       [0007]    In one embodiment, the disclosed bladder assembly may include a body, a bladder received in the body, the bladder defining an internal volume and including an annular sealing bead, the annular sealing bead defining an opening into the internal volume, and a sealing member including a shaft having a first end and a second end, and an engagement portion connected proximate the second end, the sealing member being partially received within the internal volume and being moveable between at least a first position, wherein the engagement portion is spaced from the sealing bead, and a second position, wherein the sealing bead is compressed between the engagement portion and the body. 
         [0008]    In another embodiment, the disclosed bladder assembly may include a body defining a bore, a bladder closely received in the bore, the bladder defining an internal volume and including an annular sealing bead, the sealing bead defining an opening into the internal volume, a plug connected to the body to enclose the bore, the plug defining a recess and a bore extending from the recess, and a sealing member including a shaft having a first end and a second end, wherein the shaft extends through the bore in the plug such that the first end extends outside of the body and the second end extends into the internal volume, and an engagement portion connected proximate the second end, the engagement portion including a ramped portion, a seat portion and a flange, the seat portion being positioned between the ramped portion and the flange, wherein the first end of the shaft is withdrawn from the body such that the sealing bead is seated on the seat portion and compressed between the seat portion and the body. 
         [0009]    In yet another embodiment, also disclosed is a method for sealing a bladder. The bladder may define an internal volume and may include an annular sealing bead, the sealing bead may define an opening into the internal volume. The method may include the steps of (1) providing a sealing member and a body, the body defining a bore, the sealing member including a shaft having a first end and a second end, and an engagement portion connected proximate the second end; (2) inserting the sealing member into the bladder such that the engagement portion is received in the internal volume and a portion of the shaft extends from the internal volume; (3) inserting the bladder into the bore; (4) plugging the bore such that the bladder and the engagement portion of the shaft are enclosed in the bore and the first end of the shaft extends outside of the body; and (5) applying a pulling force to the first end of the shaft to at least partially withdraw the sealing member and compress the sealing bead between the body and the engagement portion. 
         [0010]    Other embodiments of the disclosed bladder assembly and method will become apparent from the following detailed description, the accompanying drawings and the appended claims. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]      FIG. 1  is a side elevational view, in section, of one embodiment of the disclosed bladder assembly, shown in a sealed configuration; 
           [0012]      FIG. 2  is a side elevational view, in section, of a portion of the body of the bladder assembly of  FIG. 1 ; 
           [0013]      FIG. 3  is a side elevational view, in section, of the bladder of the bladder assembly of  FIG. 1 ; 
           [0014]      FIG. 4  is a side elevational view, in section, of the sealing member of the bladder assembly of  FIG. 1 ; 
           [0015]      FIG. 5  is a side elevational view, in section, of the bladder assembly of  FIG. 1 , shown during a first stage of assembly; 
           [0016]      FIG. 6  is a side elevational view, in section, of the bladder assembly of  FIG. 5 , shown during a second stage of assembly; 
           [0017]      FIG. 7  is a side elevational view, in section, of the bladder assembly of  FIG. 6 , shown during a third stage of assembly; 
           [0018]      FIG. 8  is a side elevational view, in section, of the bladder assembly of  FIG. 7 , shown during a fourth, sealed stage of assembly; 
           [0019]      FIG. 9  is flow chart illustrating one embodiment of the disclosed method for sealing a bladder. 
           [0020]      FIG. 10  is a flow diagram of aircraft production and service methodology; and 
           [0021]      FIG. 11  is a block diagram of an aircraft. 
       
    
    
     DETAILED DESCRIPTION 
       [0022]    Referring to  FIG. 1 , one embodiment of the disclosed bladder assembly, generally designated  10 , may include a body  12 , a bladder  14  and sealing assemblies  16 . While the bladder assembly  10  is shown in  FIG. 1  with two sealing assemblies  16  on opposed first and second ends  18 ,  20  of the body  12 , those skilled in the art will appreciate that only one sealing assembly  16  (or three or more sealing assemblies  16 ) may be used depending on the application and without departing from the scope of the present disclosure. 
         [0023]    The body  12  may be any structure capable of receiving the bladder  14 , such as within a bore  22  defined by the body  12 . For example, the body  12  may be an elongated tubular structure, as shown in  FIG. 1 . However, bodies of various shapes, geometries and sizes may be used. As one specific, non-limiting example, the body  12  may be a component of a vehicle, such as a terrestrial vehicle, a waterborne vessel or an aerospace vehicle, that may be subjected to pressurization while in use. 
         [0024]    The body  12  may be constructed from various materials. As one non-limiting example, the body  12  may be formed from a polymeric material, such as an extruded plastic. As another non-limiting example, the body  12  may be formed from a composite material, such as a composite material having reinforcing fibers in a polymer (e.g., epoxy-based) matrix. As yet another non-limiting example, the body  12  may be formed from a metal or metal alloy, such as a high-strength aluminum alloy. 
         [0025]    While not shown in  FIG. 1 , the body  12  may include various pores, cracks, holes or other through passageways in fluid communication with the bore  22 , thereby rendering the bore  22  a non-fluid-tight bore. Therefore, use of the bladder  14  within the non-fluid-tight bore  22  may facilitate pressure testing of the body  12 . Of course, a fluid-tight (or substantially fluid-tight) bore  22  may also be used, thereby rendering the bladder  14  a prophylactic component during pressure testing of the body  12 . 
         [0026]    The bore  22  may extend from proximate (at or near) the first end  18  of the body  12  to proximate the second end  20  of the body  12 . As shown in  FIG. 2 , an opening  24  in the first end  18  of the body  12  may provide access to the bore  22 . A similar opening may be formed in the second end  20  of the body  12  to provide access to the bore  22  at the second end  20  of the body  12 . 
         [0027]    Referring to  FIG. 2 , the bore  22  defined by the body  12  may have a cross-sectional profile and a maximum inner cross-sectional dimension (e.g., inner diameter) D configured to closely receive the bladder  14 . For example, the bore  22  may have a generally circular cross-sectional profile. However, bores  22  having various shapes and configurations may be used without departing from the scope of the present disclosure. 
         [0028]    Referring to  FIG. 3 , the bladder  14  may include a body  26  having a first end  28  and a second end  30 . In one particular construction, the body  26  of the bladder  14  may be elongated along a longitudinal axis A such that the first end  28  of the body  26  is longitudinally opposed from the second end  30  of the body  26 . While the bladder  14  is shown in  FIG. 3  having an elongated cylindrical body  26  with a shape and configuration that closely corresponds to the shape and configuration of the bore  22  in the body  12  (e.g., the outer diameter E of the bladder  14  (unloaded) may be substantially equal to the inner diameter D of the bore  22 ), those skilled in the art will appreciate that the body  26  of the bladder  14  may have various shapes and configurations, depending, for example, on the shape and configuration of the bore  22  in the body  12 , without departing from the scope of the present disclosure. 
         [0029]    The body  26  of the bladder  14  may be formed from an elastomeric material, such as by molding or extruding the elastomeric materials. Various elastomeric materials and forming techniques may be used. Elastomeric material selection may include consideration of end application, such as the type of pressurizing fluid (e.g., air; water; hydraulic fluid) that may be used to pressurize the bladder. As one non-limiting example, the body  26  of the bladder  14  may be formed from natural and/or synthetic rubber. As another non-limiting example, the body  26  of the bladder  14  may be formed from silicone rubber. As yet another non-limiting example, the body  26  of the bladder  14  may be formed from a fluoropolymer elastomer material. 
         [0030]    The body  26  of the bladder  14  may define an internal volume  32 . A first opening  34  in the body  26  may provide access to the internal volume  32  proximate the first end  28  of the body  26 . A second opening  36  in the body  26  may provide access to the internal volume  32  proximate the second end  30  of the body  26 . 
         [0031]    At this point, those skilled in the art will appreciated that the bladder  14  has two openings  34 ,  36  because the body  12  ( FIG. 1 ) that receives the bladder  14  has two openings  24  ( FIG. 2 ). However, bladders  14  having only one opening  34  (e.g., the second end  30  may be pre-sealed) and bladders  14  having three or more openings (e.g., a T-shaped bladder) are also contemplated. 
         [0032]    A first sealing bead  38  may be connected to the body  26  of the bladder  14  proximate the first end  28  of the body  26 . The first sealing bead  38  may be an annular structure and may protrude inward from the body  26 . In one particular construction, the first sealing bead  38  may be integral with the first end  28  of the body  26  (the first sealing bead  38  and the body  26  may be formed as a single monolithic body). For example, the first sealing bead  38  may be co-molded with the first end  28  of the body  26 . 
         [0033]    A second sealing bead  40  may be connected to the body  26  of the bladder  14  proximate the second end  30  of the body  26 . The second sealing bead  40  may be an annular structure and may protrude inward from the body  26 . In one particular construction, the second sealing bead  40  may be integral with the second end  30  of the body  26  (the second sealing bead  40  and the body  26  may be formed as a single monolithic body). For example, the second sealing bead  40  may be co-molded with the second end  30  of the body  26 . 
         [0034]    Thus, as is described in greater detail herein, the first and second sealing beads  38 ,  40  may act as integral  0 -rings for sealing the first and second ends  28 ,  30 , respectively, of the body  26  of the bladder  14 . While the first and second sealing beads  38 ,  40  are shown in the drawings as having a generally circular or ellipsoidal ( 0 -ring) cross-sectional profile, the use of other profile shapes/geometries is also contemplated. 
         [0035]    Referring for a moment to  FIG. 8 , each sealing assembly  16  (only one is shown in  FIG. 8 ; both are shown in  FIG. 1 ) may include a sealing member  50 , a plug  52 , a fastening member  54  and a retaining member  56 . Optionally, such as, for example, in very high pressure applications, the sealing assembly  16  may additionally include a back-up ring  58 . Additional (or fewer) components may be included in the sealing assembly  16  without departing from the scope of the present disclosure. 
         [0036]    Referring now to  FIG. 4 , the sealing member  50  of each sealing assembly  16  ( FIG. 1 ) may include a shaft  60  and an engagement portion  62 . The shaft  60  may be elongated along a longitudinal axis B, and may include a first end  64  longitudinally opposed from a second end  66 . The shaft  60  may optionally define a fluid channel  68  that extends from proximate the first end  64  to proximate the second end  66 . 
         [0037]    In one specific realization, the outer surface  70  of the shaft  60  may be threaded. Therefore, the retaining member  56  ( FIG. 7 ), which may be a nut (e.g., a jam nut) or the like, may be threaded onto the shaft  60 , as is described in greater detail herein. Of course, when the retaining member  56  does not require a threaded engagement with the shaft  60 , the outer surface  70  of the shaft  60  need not be threaded. 
         [0038]    The engagement portion  62  may be circumferentially received over the shaft  60  proximate the second end  66  of the shaft  60 . As shown in  FIG. 4 , the shaft  60  and the engagement portion  62  may be separate pieces, and the engagement portion  62  may be fixedly connected to the second end  66  of the shaft  60 , such as with a threaded engagement, an interference fit, mechanical fasteners, one or more welds or the like. Alternatively, the engagement portion  62  may be integral with the shaft  60  (the shaft  60  and the engagement portion  62  may be formed as a single monolithic body). 
         [0039]    The engagement portion  62  may include a first end  72  and a second end  74  longitudinally opposed from the first end  72 . The engagement portion  62  may include a ramped portion  76  proximate the first end  72  of the engagement portion  62 , an optional tapered portion  78  proximate the second end  74  of the engagement portion  62 , and a seat portion  80  extending between the ramped portion  76  and the tapered portion  78 . 
         [0040]    The ramped portion  76  of the engagement portion  62  may be ramped (e.g., may increase in diameter) from proximate the first end  72  of the engagement portion  62  to proximate the seat portion  80 . The tapered portion  78  of the engagement portion  62  may be tapered (e.g., may decrease in diameter) from proximate the seat portion  80  to proximate the second end  74  of the engagement portion  62 . The seat portion  80  may have a substantially uniform diameter extending from proximate the ramped portion  76  to proximate the tapered portion  78 , which may define a first gland surface  82 . The transition from the tapered portion  78  to the seat portion  80  may define a flange  84 , which may define a second gland surface  86 . 
         [0041]    Referring to  FIGS. 5-9 , disclosed is a method  200  ( FIG. 9 ) for sealing a bladder. The method  200  is described below with reference to  FIGS. 5-8 , in which only one of the sealing assemblies  16  is shown. Those skilled in the art will appreciate that the other sealing assembly  16  (shown in  FIG. 1 , but not shown in  FIGS. 5-8 ) may be assembled in a manner similar to the sealing assembly  16  shown in  FIGS. 5-8  to fully assemble and seal the disclosed bladder assembly  10 . 
         [0042]    The first assembly step (block  202  in  FIG. 9 ) may include providing a body  12 , a bladder  14  and a sealing assembly  16 . 
         [0043]    The second assembly step (block  204  in  FIG. 9 ) may include inserting the sealing member  50  into the bladder  14 . As shown in  FIG. 5 , the engagement portion  62  of the sealing member  50  may be inserted into the internal volume  32  of the bladder  14  by way of the first opening  34  ( FIG. 3 ) in the body  26  of the bladder  14 . The tapered portion  78  of the engagement portion  62  may facilitate insertion of the sealing member  50  through the first opening  34  in the bladder  14  by urging the first sealing bead  38  outward as the tapered portion  78  is urged through the first opening  34 . 
         [0044]    The third assembly step (block  206  in  FIG. 9 ) may include inserting the bladder  14  into the body  12 . As shown in  FIG. 5 , an opening  24  in the body  12  may provide access to the bore  22  defined by the body  12 . The bladder  14  (with the sealing member  50  inserted therein and extending therefrom) may be inserted into the bore  22  defined by the body  12  by way of the opening  24  in the body  12 . When the bladder  14  is fully inserted into the body  12 , the shaft  60  of the sealing member  50  may extend through the opening  24  such that a portion of the shaft  60  is outside of the body  12 . 
         [0045]    The fourth assembly step (block  208  in  FIG. 9 ) may include plugging the opening  24  in the body  12 . As shown in  FIG. 6 , the plug  52  may be inserted into the opening  24  in the body  12  to enclose the opening  24 , while permitting the shaft  50  of the sealing member  50  to extend therethrough. 
         [0046]    The plug  52  may include a distal end  90  sized and shaped to be received through the opening  24  in the body  12  and to extend into the bore  22 . The distal end  90  of the plug  52  may include a face surface  91 , which may define a third gland surface. A recess  94  may be formed in the face surface  91  to receive therein a portion of the engagement portion  62  of the sealing member  50  during sealing, as is described in greater detail herein. The rear wall  96  of the recess  94  may define the depth of the recess  94  and may function as a stop for the engagement portion  62  of the sealing member  50 . 
         [0047]    The plug  52  may further define a bore  98  that may longitudinally extend from the recess  94  to the proximal end  100  of the plug  52 . The bore  98  may be sized and shaped to closely receive the shaft  60  of the sealing member  50 . Therefore, the shaft  60  of the sealing member  50  may extend (e.g., slidably) through the plug  52 , but an interference engagement between the engagement portion  62  of the sealing member  50  and the rear wall  96  of the recess  94  may inhibit rearward movement (arrow R in  FIG. 8 ) of the sealing member  50  beyond a pre-defined point. 
         [0048]    The plug  52  may include an annular flange  102  to engage the body  12 , thereby controlling the depth to which the distal end  90  of the plug  52  protrudes into the bore  22  of the body  12 . As shown in  FIG. 6 , the flange  102  of the plug  52  may be in abutting engagement with the body  12 . As shown in  FIG. 7 , the fastening member  54  may secure the plug  52  to the body  12 . As one specific, non-limiting example, the fastening member  54  may be a C-nut or the like, and may be received over the proximal end  100  of the plug  52  and threaded into engagement with the body  12 , as shown in  FIG. 7 . However, various fastening members, such as bolts, screws, pins or the like, may be used to secure the plug  52  to the body  12  without departing from the scope of the present disclosure. 
         [0049]    In one optional implementation, the back-up ring  58  may be inserted prior to inserting the plug  52 . The back-up ring  58  may be positioned against the sealing bead  38  of the bladder  14  and may be urged against the sealing bead  38  by the face surface  91  of the plug  52 . Therefore, rather than the face surface  91  of the plug  52  acting as the third gland surface, the back-up ring  58  may act as the third gland surface  92 , as shown in  FIG. 7 . 
         [0050]    The fifth assembly step (block  210  in  FIG. 9 ) may include withdrawing the sealing member  50  from the body  12  by applying a pulling force (arrow R in  FIG. 8 ) to the shaft  60  of the sealing member  50  to move the engagement portion  62  of the sealing member  50  from a first position (engagement portion  62  not engaged with the sealing bead  38 ) to a second position (engagement portion  62  engaged with the sealing bead  38 ). Therefore, the step of withdrawing the sealing member  50  from the body  12  may pre-load the bladder  14 . 
         [0051]    Various techniques may be used to withdraw the sealing member  50  from the body  12 . As one example, the sealing member  50  may be manually withdrawn, such as by gripping the shaft  60  of the sealing member  50  and applying a pulling force (arrow R). As another example, the sealing member  50  may be withdrawn by threading the retaining member  56  onto the shaft  60  of the sealing member  50  and tightening the retaining member  56  against the plug  52  to urge the shaft in the direction shown by arrow R. Other techniques may also be used without departing from the scope of the present disclosure. 
         [0052]    Referring to  FIGS. 7 and 8 , as the sealing member  50  is withdrawn (arrow R) from the body  12 , the engagement portion  62  of the sealing member  50  may engage and compress the sealing bead  38  of the bladder  14 . Initially, the ramped portion  76  may compress the sealing bead  38 . As the sealing member  50  is further withdrawn, the sealing bead  38  may become seated on the seat portion  80  of the sealing member  50  and, therefore, may be radially compressed between the seat portion  80  and the body  12 . As the sealing member  50  is still further withdrawn, the sealing bead  38  may become axially compressed between the back-up ring  58  and the flange  84  of the engagement portion  62  of the sealing member  50 . Eventually, the engagement portion  62  of the sealing member  50  may come into abutting engagement with the rear wall  96  of the recess  94  in the plug  52 , as shown in  FIG. 8 , thereby inhibiting further withdrawal of the sealing member  50 . 
         [0053]    Thus, when the sealing member  50  is fully withdrawn, a gland may be defined by the first, second and third gland surfaces  82 ,  86 ,  92 , which may be defined, respectively, by the seat portion  80  of the engagement portion  62  of the sealing member  50 , the flange  84  of the engagement portion  62  of the sealing member  50 , and the back-up ring  58  (or the face surface  91  of the plug  52 ). 
         [0054]    The sixth assembly step (block  212  in  FIG. 9 ) may include retaining the sealing member  50  in the withdrawn configuration. As shown in  FIG. 8 , the retaining member  56  may be a nut, such as a jam nut, and may be threaded onto the shaft  60  of the sealing member  50  and tightened against the plug  52  to retain the shaft  60  in the withdrawn configuration. However, use of other retaining members and retaining techniques is also contemplated. As one alternative, the retaining member  56  may be a pin engaged with the shaft  60  of the sealing member  50 . As another alternative, the retaining member  56  may be a clamp secured to the shaft  60  of the sealing member  50 . 
         [0055]    Accordingly, disclosed is a system and method for sealing a bladder  14  within a body  12 . Once sealed (pre-loaded), the bladder  14  may be pressurized, such as by introducing a fluid (e.g., pressurized air or hydraulic fluid) to the internal volume  32  of the bladder  14  by way of the fluid channel  68  ( FIG. 4 ) defined by the shaft  60  of the sealing member  50 . 
         [0056]    Examples of the disclosure may be described in the context of an aircraft manufacturing and service method  1000 , as shown in  FIG. 10 , and an aircraft  1002 , as shown in  FIG. 11 . During pre-production, example method  1000  may include specification and design  1004  of the aircraft  1002  and material procurement  1006 . During production, component and subassembly manufacturing  1008  and system integration  1010  of the aircraft  1002  takes place. Thereafter, the aircraft  1002  may go through certification and delivery  1012  in order to be placed in service  1014 . While in service by a customer, the aircraft  1002  is scheduled for routine maintenance and service  1016 , which may also include modification, reconfiguration, refurbishment and the like. 
         [0057]    Each of the processes of method  1000  may be performed or carried out by a system integrator, a third party, and/or an operator (e.g., a customer). For the purposes of this description, a system integrator may include without limitation any number of aircraft manufacturers and major-system subcontractors; a third party may include without limitation any number of venders, subcontractors, and suppliers; and an operator may be an airline, leasing company, military entity, service organization, and so on. 
         [0058]    As shown in  FIG. 11 , the aircraft  1002  produced by example method  1000  may include an airframe  1018  with a plurality of systems  1020  and an interior  1022 . Examples of high-level systems  1020  include one or more of a propulsion system  1024 , an electrical system  1026 , a hydraulic system  1028 , and an environmental system  1030 . Any number of other systems may be included. Although an aerospace example is shown, the principles of the invention may be applied to other industries, such as the automotive industry. 
         [0059]    Apparatus and methods embodied herein may be employed during any one or more of the stages of the production and service method  1000 . For example, components or subassemblies corresponding to production process  1008  may be fabricated or manufactured in a manner similar to components or subassemblies produced while the aircraft  1002  is in service. Also, one or more apparatus examples, method examples, or a combination thereof may be utilized during the production stages  1008  and  1010 , for example, by substantially expediting assembly of or reducing the cost of an aircraft  1002 . Similarly, one or more of apparatus examples, method examples, or a combination thereof may be utilized while the aircraft  1002  is in service, for example and without limitation, to maintenance and service  1016 . 
         [0060]    Although various embodiments of the disclosed bladder assembly and method have been shown and described, modifications may occur to those skilled in the art upon reading the specification. The present application includes such modifications and is limited only by the scope of the claims.