Abstract:
An example gas turbine engine includes an engine casing and an engine liner within the engine casing. One of the engine casing or the engine liner includes a first attachment structure. The other of the engine casing or the engine liner defines a track guide. A slideable member is moveable within the track guide between an engaged position and a disengaged position. The slideable member includes a second attachment structure engageable with the first attachment structure to secure the engine liner relative the engine casing when the slideable member is in the engaged position.

Description:
BACKGROUND 
     An exhaust section of a typical gas turbine engine includes a removable liner secured relative to an exhaust duct. Positioning the liner within the exhaust duct insolates the exhaust duct from the thermal energy of flow through the exhaust. The engine&#39;s complex manufacturing tolerances and complicated flow path make securing the liner within the exhaust duct difficult. Thermal energy of flow through the exhaust also expands and contracts the secured liner. A robust liner securing strategy typically accommodates these thermal energy induced fluctuations. Liners in other sections of the engine face similar issues. Liners are often removed from the engine for repair, inspection, etc. 
     In one securing arrangement, brackets are associated with the exhaust liner and exhaust duct. The brackets each include corresponding apertures. A separate pin is inserted through the apertures, which are aligned during assembly, to support the exhaust liner relative to the exhaust duct. The separate pin typically extends along the entire axial length of the liner. Installing the lengthy, separate pin is difficult because of the distance the separate pin must travel to move between an uninstalled position and an installed position within the bracket apertures. More specifically, accessing areas of the engine that provide adequate clearances for manipulating the lengthy, separate pin during installation is often difficult. As an example, the curved inner wall of some curved exhausts blocks moving the pin to a position appropriate for insertion into the bracket apertures. Removing the pin from the bracket apertures is similarly difficult. 
     SUMMARY 
     An example gas turbine engine includes an engine casing and an engine liner within the engine casing. One of the engine casing or the engine liner includes a first attachment structure. The other of the engine casing or the engine liner defines a track guide. A slideable member is moveable within the track guide between an engaged position and a disengaged position. The slideable member includes a second attachment structure engageable with the first attachment structure to secure the engine liner relative the engine casing when the slideable member is in the engaged position. 
     An example liner anchoring assembly includes a slideable member receivable within a track guide defined by an engine liner or an engine casing. The slideable member is moveable within the track guide between a first position and a second position, the slideable member in the second position is configured to limit more movement of the engine liner relative the engine casing than the slideable member in the first position. A pin structure or an apertured portion translates with the slideable member. The apertured portion receives the pin structure within an aperture when the slideable member is in the second position. 
     An example method of securing an engine liner includes positioning an engine liner within an engine casing in a first position, and sliding a liner anchoring structure relative the liner and the casing within a guide defined by the liner or the casing. The method includes sliding the liner anchoring structure to secure the liner in the first position during the sliding. 
     These and other features of the example disclosure can be best understood from the following specification and drawings, the following of which is a brief description: 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  schematically shows sectional view of an example gas turbine engine. 
         FIG. 2  schematically shows another example gas turbine engine. 
         FIG. 3  shows an example liner anchoring assembly within a portion of the  FIG. 2  engine. 
         FIG. 4A  shows the sectional view through line  4 - 4  of  FIG. 3  with the liner anchoring assembly in a disengaged position. 
         FIG. 4B  shows a sectional view through line  4 - 4  of  FIG. 3  with the liner anchoring assembly in an engaged position. 
         FIG. 5  shows a sectional view through line  5 - 5  of  FIG. 3 . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       FIG. 1  schematically illustrates an example gas turbine engine  10  including (in serial flow communication) a fan section  14 , a low pressure compressor  18 , a high pressure compressor  22 , a combustor  26 , a high pressure turbine  30 , and a low pressure turbine  34 . The gas turbine engine  10  is circumferentially disposed about an engine centerline X. During operation, the fan section  14  intakes air, and the compressors  18 ,  22  pressurize the air. The combustor  26  burns fuel mixed with the pressurized air. The high and low pressure turbines  30 ,  34  extract energy from the gases exiting the combustor  26 . 
     In a two-spool design, the high pressure turbine  30  utilizes the extracted energy from the hot combustion gases to power the high pressure compressor  22  through a high speed shaft  38 , and a low pressure turbine  34  utilizes the energy extracted from the hot combustion gases to power the low pressure compressor  18  and the fan section  14  through a low speed shaft  42 . The example method may be applied to other architectures such as a single spool axial design, a three spool axial design, and other architectures. 
     Referring to the  FIG. 2  schematic, there is shown an example turbo jet engine  50 . The turbo jet engine  50  includes a fan section  54 , a compressor section  58 , a combustor section  62 , a turbine section  66 , an augmentor section  70  and a nozzle section  74 . The compressor section  58 , combustor section  62 , and turbine section  66  are generally referred to as the core engine. An axis A of the engine  50  is generally disposed and extends longitudinally through the sections. An outer engine duct structure  78 , or casing, and an inner cooling liner structure  82  provide an annular secondary fan bypass flow path  86  around a primary exhaust flow path E through an exhaust section  80  of the engine  50 . The bypass flow path  86  receives bypass flow from the fan section  54 . 
     Referring now to  FIGS. 3 through 4B  with continuing reference to  FIG. 2 , the example duct structure  78  supports the liner structure  82  with a liner anchoring assembly  100 . The example liner structure  82  is a nickel liner structure. The example duct structure  78  comprises titanium materials. 
     The duct structure  78  defines a plurality of track guides  104  that each receives a track portion  108  of the respective liner anchoring assembly  100 . In this example, the track guides  104  are defined along an interior portion of the duct structure  78  and are aligned with the engine axis A such that the liner anchoring assembly  100 , when received within a respective one of the track guides  104 , extends from the duct structure  78  toward the engine axis A. The example duct structure  78  defines several track guides  104  annularly arranged about the engine axis A. 
     The liner anchoring assembly  100 , a type of slideable member, slides, translates, or otherwise moves within the track guides  104  between the disengaged position of  FIG. 4A  and the engaged position of  FIG. 4B . The example track guides  104  hold the liner anchoring assembly  100  such that relative movements of the liner anchoring assembly  100  are back and forth in a single direction. 
     In the engaged position, a plurality of pins  112 , mounted on pin stands  114  extending from the track portion  108 , are received within a plurality of apertures  116  defined by corresponding brackets  120  extending from the liner structure  82 . When received, the pins  112  fit within the apertures  116  to limit radial movement of the brackets  120  relative to the pins  112 . The pins  112  and brackets  120  thus act as attachment structures securing the liner anchoring assembly  100  to the liner structure  82 . Other example attachment structures include hooks or other features appropriate for engaging the brackets  120  relative to the liner anchoring assembly  100  to limit radial movement of the brackets  120 . 
     The liner anchoring assembly  100  secures the liner structure  82  relative the duct structure  78  when the liner anchoring assembly  100  is in the engaged position. A plurality of liner supports  124  space the liner structure  82  from the duct structure  78  and facilitate aligning the apertures  116  with the pins  112  as the pins  112  move to the engaged position. 
     The pins  112  of the example liner anchoring assembly  100  are each shorter than the overall axial length of the liner structure  82 . Pins  112  that are shorter require less movement of the liner anchoring assembly  100  to disengage form the apertures  116  than pins  112  that are longer. Disengaging the pins  112  thus requires less movement of the liner anchoring assembly  100  than if the pins  112  extended the entire length of the liner structure  82 . Smaller movements of the liner anchoring assembly  100  require less clearance within the engine  50  than larger movements. 
     The pins  112  on the example liner anchoring assembly  100  are axially aligned with each other. This arrangement facilitates sliding the liner anchoring assembly  100  in a single direction to move the pins  112  to and from a position received within the apertures  116 . 
     In the installed position of  FIG. 4B , screws or similar fasteners  128  may be used to minimize relative linear displacement between the liner anchoring assembly  100  and the duct structure  78  after moving the assembly  100  to the installed position. The fasteners  128  thus prevent the liner anchoring assembly  100  from sliding to a disengaged position. The example threaded fasteners  128  are positioned an area of the engine  50  providing access for securing the threaded fasteners  128  with a pneumatic tool for example. 
     Although shown as a liner anchoring assembly  100  moving within the track guides  104  defined by the duct structure  78 , other examples may include track guides  104  defined by the liner structure  82 . In such an example, the liner anchoring assembly  100  slides to engage apertured brackets (not shown) extending from the duct structure  78 . 
     Referring to  FIG. 5 , in this example, a cover plate  132  lines the duct structure  78  to help hold the liner anchoring assembly  100  within the track guides  104 . The pin stands  114  of the liner anchoring assembly  100  extend through apertures  136  defined by the track guides  104 . The apertures  136  permit movement of the liner anchoring assembly  100  between the engaged and the disengaged positions. 
     Although a preferred embodiment has been disclosed, a worker of ordinary skill in this art would recognize that certain modifications would come within the scope of this invention. For that reason, the following claims should be studied to determine the true scope and content of this invention.