Abstract:
A horizontal support tool for an engine build stand, the horizontal support tool includes a support tube along an axis and a tie shaft between a handle and a puck assembly, said puck assembly including a puck selectively extendable and retractable transverse to the axis in response to rotation of the handle. A method of horizontally assembling a portion of a gas turbine engine including mounting a first module to an engine build stand; installing a horizontal support tool into the first module, the horizontal support tool supported in a spherical bearing supported by the engine build stand; and installing a second module to the first module, the horizontal support tool operable to at least partially support second module.

Description:
BACKGROUND 
       [0001]    The present disclosure relates to gas turbine engine build stands and, more particularly, relates to a rotor support tool for horizontal assembly. 
         [0002]    At least some gas turbine engines include, in serial flow arrangement, a high-pressure compressor for compressing air flowing through the engine, a combustor in which fuel is mixed with the compressed air and ignited to form a high temperature gas stream, and a high pressure turbine. The high-pressure compressor, combustor and high-pressure turbine are oftentimes collectively referred to as the core engine. 
         [0003]    Various gas turbine engine build stands are presently available for use in connection with the assembly of gas turbine engines. One type of engine stand includes horizontally disposed rings which mount an engine such that the engine longitudinal axis extends generally vertical. Since the engine is effectively vertical, fluids may leak from the engine and scaffold stands are required for technicians. 
         [0004]    In another type of engine stand, a generally horizontally disposed shaft extends through a vertical support member to mount the engine such that the engine longitudinal axis extends generally horizontally. Since the engine is effectively cantilevered, the engine may be subjected to a stress and force moment since the engine center of gravity is displaced from the vertical support. 
       SUMMARY 
       [0005]    A horizontal support tool for an engine build stand, the horizontal support tool according to one disclosed non-limiting embodiment of the present disclosure can include a support tube along an axis; and a tie shaft between a handle and a puck assembly, the puck assembly including a puck selectively extendable and retractable transverse to the axis in response to rotation of the handle. 
         [0006]    A further embodiment of the present disclosure may include wherein the support tube is manufactured of a nonmetallic composite material to fit within a shaft of a gas turbine engine. 
         [0007]    A further embodiment of the present disclosure may include wherein the support tube is manufactured of layered uniaxial fibers. 
         [0008]    A further embodiment of the present disclosure may include wherein the puck is manufactured of a nonmetallic composite material. 
         [0009]    A further embodiment of the present disclosure may include wherein the puck assembly includes a return assembly to facilitate retraction of the puck. 
         [0010]    A further embodiment of the present disclosure may include, wherein the a return assembly spring biases of the puck. 
         [0011]    A further embodiment of the present disclosure may include wherein the puck is generally rectilinear. 
         [0012]    A further embodiment of the present disclosure may include wherein the puck provides a line contact. 
         [0013]    An engine build stand, according to one disclosed non-limiting embodiment of the present disclosure can include a support structure; a spherical bearing supported by the support structure; and a horizontal support tool receivable within the spherical bearing. 
         [0014]    A further embodiment of the present disclosure may include, wherein the horizontal support tool includes: a support tube along an axis; and a tie shaft between a handle and a puck assembly, the puck assembly including a puck selectively extendable and retractable transverse to the axis in response to rotation of the handle. 
         [0015]    A further embodiment of the present disclosure may include wherein the support tube is manufactured of a nonmetallic composite material. 
         [0016]    A further embodiment of the present disclosure may include a turnbuckle to adjust a position of the horizontal support tool. 
         [0017]    A further embodiment of the present disclosure may include a load cell to measure a weight applied to the horizontal support tool. 
         [0018]    A method of horizontally assembling a portion of a gas turbine engine, according to one disclosed non-limiting embodiment of the present disclosure can include mounting a first module to an engine build stand; 
         [0019]    installing a horizontal support tool into the first module, the horizontal support tool supported in a spherical bearing supported by the engine build stand; and 
         [0020]    installing a second module to the first module, the horizontal support tool operable to at least partially support the second module. 
         [0021]    A further embodiment of the present disclosure may include wherein the first module includes a bearing structure, a high pressure intermediate case (IMC) mounted to the bearing structure, and a high pressure compressor case with rotational compressor hardware therein, the high pressure compressor case mounted to the IMC. 
         [0022]    A further embodiment of the present disclosure may include at least partially supporting the first module via a shipping fixture. 
         [0023]    A further embodiment of the present disclosure may include preloading the horizontal support tool prior to removing the shipping fixture. 
         [0024]    A further embodiment of the present disclosure may include supporting rotational hardware within the second module by the horizontal support tool. 
         [0025]    A further embodiment of the present disclosure may include, wherein the second module includes a high pressure turbine case. 
         [0026]    A further embodiment of the present disclosure may include preloading the horizontal support tool prior to installation of the second module. 
         [0027]    The foregoing features and elements may be combined in various combinations without exclusivity, unless expressly indicated otherwise. These features and elements as well as the operation thereof will become more apparent in light of the following description and the accompanying drawings. It should be understood, however, the following description and drawings are intended to be exemplary in nature and non-limiting. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0028]    Various features will become apparent to those skilled in the art from the following detailed description of the disclosed non-limiting embodiments. The drawings that accompany the detailed description can be briefly described as follows: 
           [0029]      FIG. 1  is a schematic cross-section of an example gas turbine engine architecture; 
           [0030]      FIG. 2  is a perspective view of a horizontal engine build stand without a horizontal support tool installed; 
           [0031]      FIG. 3  is a side view of the horizontal engine build stand without the horizontal support tool installed; 
           [0032]      FIG. 4  is a side view of the horizontal support tool installed within a first module that includes a #3 bearing structure, a high pressure intermediate case (IMC), and a high pressure compressor case with the rotational compressor hardware therein; 
           [0033]      FIG. 5  is a perspective view of a horizontal engine build stand with a horizontal support tool installed within the first module and a shipping fixture; 
           [0034]      FIG. 6  is a side view of the horizontal engine build stand with the horizontal support tool installed within the first module and a shipping fixture; 
           [0035]      FIG. 7  is a sectional view of the horizontal support tool; 
           [0036]      FIG. 8  is an expanded sectional view of one end of the horizontal support tool; 
           [0037]      FIG. 9  is an expanded sectional view of the opposite end of the horizontal support tool; 
           [0038]      FIG. 10  is a top view of the horizontal support tool; 
           [0039]      FIG. 11  is a method of horizontally assembling a portion of a gas turbine engine; 
           [0040]      FIG. 12  is a perspective view of a horizontal engine build stand with a horizontal support tool installed within the first module and the shipping fixture removed; 
           [0041]      FIG. 13  is a perspective view of a horizontal engine build stand with a horizontal support tool installed within the first module and a second module; 
           [0042]      FIG. 14  is a side view of the horizontal engine build stand with the horizontal support tool installed within the first module and a second module; 
           [0043]      FIG. 15  is a perspective view of a horizontal engine build stand with a horizontal support tool installed within the first module, the second module and a third module; 
           [0044]      FIG. 16  is a side view of the horizontal engine build stand with the horizontal support tool installed within the first module, the second module and a third module; 
           [0045]      FIG. 17  is a perspective view of a horizontal engine build stand with the horizontal support tool removed from the first module, the second module and a third module; and 
           [0046]      FIG. 18  is a side view of the horizontal engine build stand with the horizontal support tool removed from the first module, the second module and a third module. 
       
    
    
     DETAILED DESCRIPTION 
       [0047]      FIG. 1  schematically illustrates a gas turbine engine  20 . The gas turbine engine  20  is disclosed herein as a two-spool turbo fan that generally incorporates a fan section  22 , a compressor section  24 , a combustor section  26  and a turbine section  28 . The fan section  22  drives air along a bypass flowpath and along a core flowpath for compression by the compressor section  24 , communication into the combustor section  26 , then expansion through the turbine section  28 . Although depicted as a turbofan in the disclosed non-limiting embodiment, it should be understood that the concepts described herein are not limited to use with turbofans as the teachings may be applied to other types of turbine engine architectures such as low bypass turbofans, turbojets, turboshafts, three-spool (plus fan) turbofans and other non-gas turbine components. 
         [0048]    The engine  20  generally includes a low spool  30  and a high spool  32  mounted for rotation about an engine central longitudinal axis “A.” The low spool  30  generally includes an inner shaft  40  that interconnects a fan  42 , a low pressure compressor (“LPC”)  44  and a low pressure turbine (“LPT”)  46 . The inner shaft  40  drives the fan  42  directly, or through a geared architecture  48  at a lower speed than the low spool  30 . An exemplary reduction transmission is an epicyclic transmission, namely a planetary or star gear system. 
         [0049]    The high spool  32  includes an outer shaft  50  that interconnects a high pressure compressor (“HPC”)  52  and high pressure turbine (“HPT”)  54 . The HPC  52 , the HPT  54  and the combustor  56  are often referred to as the engine core. A combustor  56  is arranged between the high pressure compressor  52  and the high pressure turbine  54 . The inner shaft  40  and the outer shaft  50  are concentric and rotate about the engine central longitudinal axis “A,” which is collinear with their longitudinal axes. 
         [0050]    Core airflow is compressed by the LPC  44 , then the HPC  52 , mixed with the fuel and burned in the combustor  56 , then expanded over the HPT  54 , then the LPT  46 . The turbines  54 ,  46  rotationally drive the respective high spool  32  and low spool  30  in response to the expansion. The main engine shafts  40 ,  50  are supported at a plurality of points by bearing structures  38  within the static structure  36 . 
         [0051]    With reference to  FIGS. 2 and 3 , an engine build stand  100  is utilized to support the engine core for horizontal assembly. During core assembly, a bearing, here represented as the #3 bearing structure  38 B ( FIG. 1 ), supports the rotational hardware  52 R of the HPC  52 , but until the #4 bearing structure  38 C ( FIG. 1 ) is installed, there is no aft support for the rotational hardware  52 R. The rotational engine hardware, may include the rotor stack of the HPC  52 , HPT  54 , or other rotational components. 
         [0052]    The engine build stand  100  generally includes a support structure  102  which positions a spherical bearing assembly  104 , and a horizontal support tool  106  ( FIG. 4 ) that extends through the spherical bearing assembly  104 , to support the rotational engine hardware during horizontal assembly. The support structure  102  may include one or more turnbuckles  108  or other adjustment devices that adjust the spherical bearing assembly  104 , and thus the horizontal support tool  106 . The spherical bearing assembly  104  is positioned by the turnbuckles  108  to adjust the position of the horizontal support tool  106  that, although quite stiff, will still deflect to an extent that compensation is required. 
         [0053]    With reference to  FIGS. 5 and 6 , As the horizontal support tool  106  is primarily provided to align and counteract the weight of the rotational engine hardware, the spherical bearing assembly  104  need only be adjusted in the pitch dimension to counteract weight. A load cell  110  or other such measurement device may interface with the spherical bearing assembly  104  to measure a weight applied to the horizontal support tool  106 . That is, the support rod assembly  108  may be pitched to compensate for the weight of the rotor stack as the HPC  52  is assembled. Further, as the weight of various modules are known, the horizontal support tool  106  can be pre-adjusted for an expected weight while, or prior, to the next module being assembled. 
         [0054]    With reference to  FIG. 7 , the horizontal support tool  106  generally includes a support tube  120 , a handle  122 , a puck assembly  124  and a tie shaft  126  that connects the handle  122  to the puck assembly  124 . The support tube  120  may be manufactured of a nonmetallic composite material that is exceedingly stiff. The composite material, in one example, may be manufactured of layered uniaxial fibers. That is, the horizontal support tool  106  is primarily layered uniaxial fibers and includes minimal 45 degree fibers. 
         [0055]    Rotation of the handle  122  ( FIG. 8 ) causes the tie shaft  126  to interact with a ramp  128  of the puck assembly  124  to selectively extend and retract a puck  130  with respect to the support tube  120  ( FIG. 9 ). The tie shaft  126  will retract to allow the puck  130  to lock in the engaged position. The ramp  128  translates the longitudinal motion of the tie shaft  126  to transverse motion of the puck  130  with respect to the support tool  120 . The puck  130  is selectively extended and retracted transversely to a longitudinal axis  132  of the horizontal support tool  106 . That is, the puck  130  is flush with an outer diameter of the support tube  120  for insertion of the horizontal support tool  106  into the rotational hardware  52 R of the HPC  52 , then selectively extended to provide contact with the rotational hardware. The puck  130  may be a rectilinear and relatively thin member ( FIG. 10 ) to, for example, provide essentially line contact with the rotor shaft  40  ( FIG. 9 ). The puck assembly  124  may also include a return assembly  134  ( FIG. 9 ). The return assembly  134  generally includes a spring  136  that facilitates retraction of the puck  130  in response to retraction of the tie shaft  126 . 
         [0056]    With reference to  FIG. 4 , the support tube  120  may be of a length to longitudinally position the puck  130  adjacent to an interface  140  between the HPC  52  and the shaft  50 . The interface  140  may, as shown in this example, include an aft interface hub  142 , which is received onto a high spool tie shaft  146 , and retained thereto by a shaft mid nut  148  (also shown in  FIG. 6 ). It should be appreciated that other applications for the horizontal support tool  106  may be of a length to provide other longitudinal interface locations. 
         [0057]    With reference to  FIG. 11 , a method  200  to horizontally assemble the engine core via the horizontal support tool  106  is schematically illustrated in block diagram form. It should be appreciated that although the primary steps, which utilize the horizontal support tool  106 , are described, additional or alternative steps such as measurement, quality control, and other steps may be performed but are otherwise not detailed herein. It should be further appreciated that assembly of other such hardware may also benefit herefrom. 
         [0058]    Initially, a first module  300 , and associated shipping fixture  302  therefor, is installed to the engine build stand  100  (Step  202 ;  FIGS. 2 and 3 ). In this example, the first module  300  includes a #3 bearing structure  304 , a high pressure intermediate case (IMC)  306 , and a high pressure compressor case  308  with the rotational compressor hardware  310  therein. The shipping fixture  302  positions and protects the rotational compressor hardware  310  with respect to the high pressure compressor (HPC) case  308  such that, for example, blade seals therein are not unduly contacted by the associated rotor blades. The first module  300  is installed to the engine build stand  100  such that the IMC  306  is bolted to a support ring  320  of the build cart  100  and the HPC case  308  rests upon a case support  330 . The case support  330  may be positioned to support a flange  312  of the HPC case  308  to which the shipping fixture  302  is attached. 
         [0059]    Next, the horizontal support tool  106  is installed into the first module  300  and the puck extended to support the rotational hardware  310  in a cantilevered manner (step  204 ;  FIGS. 5 and 6 ). As the weight of the first module  300  is known, the horizontal support tube  106  may be pre-adjusted in pitch for the expected weight while the shipping fixture  302  is still supported such as by an overhead hoist H. To load the horizontal support tool  106 , the turnbuckle  108  is tightened at the bottom, pulling the spherical bearing assembly  104  and the horizontal support tool  106  down and reacting at the puck end of the horizontal support tool  106 . The weight of the rotational hardware  310  is transferred from the shipping fixture  302  to the horizontal support tool  106  such that the shipping fixture  302  can be removed (step  206 ;  FIG. 12 ). 
         [0060]    Next, the support rod assembly  108  may be pre-adjusted in pitch for the expected weight of a second module  330  and the second module  330  is installed to the first module  300  (step  208 ;  FIGS. 13 and 14 ). In this example, the second module  330  is a diffuser case which is relatively light in weigh and is mounted to the HPC case  308 . Nevertheless, the support rod assembly  108  may be pre-adjusted, or adjusted concurrently with installation thereof. 
         [0061]    Next, the support rod assembly  108  may be pre-adjusted in pitch for the expected weight of a third module  340  and the third module  340  is installed to the second module  330  (step  210 ;  FIGS. 15 and 16 ). In this example, the third module  340  is a mid turbine frame  342 , a high pressure turbine case  344  with the rotational turbine hardware  346  therein, and a #4 bearing structure  348 . The third module  340  is installed to the engine build stand  100  such that the high pressure turbine case  344  is bolted to a support ring  350  such that the support ring  350  rests upon a case support  360  of the build cart  100 . 
         [0062]    Next, the case support  330  is removed (step  212 ). The support rings  320 ,  350  of the engine build stand  100  then support the engine assembly but the support rod assembly  108  remains therein. 
         [0063]    Finally, the support rod assembly  108  is unloaded, the puck is retracted, and the support rod assembly  108  is removed from the engine assembly (step  214 ;  FIGS. 17 and 18 ). The support rings  320 ,  350  on the engine build stand  100  then support the engine assembly such that the engine assembly may, for example, be rotated on the engine build stand  100  to permit further assembly such as mounting of externals, gearboxes, etc. 
         [0064]    The support rod assembly  108  and engine build stand  100  facilitates the horizontal assembly of the core engine to maintain allowable deflection limits. 
         [0065]    The use of the terms “a,” “an,” “the,” and similar references in the context of description (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or specifically contradicted by context. The modifier “about” used in connection with a quantity is inclusive of the stated value and has the meaning dictated by the context (e.g., it includes the degree of error associated with measurement of the particular quantity). All ranges disclosed herein are inclusive of the endpoints, and the endpoints are independently combinable with each other. It should be appreciated that relative positional terms such as “forward,” “aft,” “upper,” “lower,” “above,” “below,” and the like are with reference to normal operational attitude and should not be considered otherwise limiting. 
         [0066]    Although the different non-limiting embodiments have specific illustrated components, the embodiments of this invention are not limited to those particular combinations. It is possible to use some of the components or features from any of the non-limiting embodiments in combination with features or components from any of the other non-limiting embodiments. 
         [0067]    It should be appreciated that like reference numerals identify corresponding or similar elements throughout the several drawings. It should also be appreciated that although a particular component arrangement is disclosed in the illustrated embodiment, other arrangements will benefit herefrom. 
         [0068]    Although particular step sequences are shown, described, and claimed, it should be understood that steps may be performed in any order, separated or combined unless otherwise indicated and will still benefit from the present disclosure. 
         [0069]    The foregoing description is exemplary rather than defined by the limitations within. Various non-limiting embodiments are disclosed herein, however, one of ordinary skill in the art would recognize that various modifications and variations in light of the above teachings will fall within the scope of the appended claims. It is therefore to be understood that within the scope of the appended claims, the disclosure may be practiced other than as specifically described. For that reason the appended claims should be studied to determine true scope and content.