Abstract:
A flow sleeve removal tool including: a shaft having an axis; a bracket attached to the shaft including a ring configured to abut and be releasably attached to an end of a flow sleeve of a gas turbine engine; a shaft attached to the bracket and coaxial with a flow sleeve of a gas turbine engine; a counter balance attached to the shaft, and a cable connector mounted to the shaft between the counter balance and the flow sleeve, wherein the cable connector is configured to attach to a cable connected to an overhead support structure and the cable connector is at a position on the shaft at which the flow sleeve is substantially balances the counter weight.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    The invention relates to the removal and installation of combustion flow sleeves for a gas turbine engine. In particular, the invention relates to a tool to assist technicians remove and install combustion flow sleeves. 
         [0002]    A combustion flow sleeves fits into each combustion “can” in a combustor for a gas turbine engine. The flow sleeve is typically cylindrical, slides into the housing of the combustion can and surrounds the combustion liner of the can. 
         [0003]    The flow sleeve remains in a fixed position within the housing of the combustion can during operation of the gas turbine engine. The flow sleeve is removed or installed while the engine is shut down. To install or remove the flow sleeve, the sleeve is slid out of an opened end of the housing for the combustion can. 
         [0004]    Removal of the flow sleeve was conventionally performed by technicians attaching brackets to the end of the sleeve and sliding the sleeve out from the casing of the gas turbine engine. The technicians may apply to the end of a flow sleeve a bracket, such as disclosed in U.S. Pat. No. 8,782,865. They push or pull on the bracket to insert or extract the flow sleeve. 
         [0005]    The bracket may connect to a lift that assists in supporting the bracket and flow sleeve. 
       BRIEF SUMMARY OF INVENTION 
       [0006]    Flow sleeves for modern gas turbine engines tend to be heavier than those in earlier engines due to increases in size of the engines. The heavier flow sleeves are not easy to move manually into a combustion can of a gas turbine engine. Thus, there is a need for a tool to assist technicians to lift, install and remove flow sleeves. 
         [0007]    Flow sleeve removal and installations are done at the site of an in-service gas turbine engine. Tools to assist in flow sleeve removal and installation are transported to the site or remain on site at all times. Tools that are heavy, bulky or expensive are not suited for flow sleeve installation or removal on site of the gas turbine engine. A flow sleeve installation tool has been conceived and is disclosed herein that is light, compact and inexpensive. 
         [0008]    A flow sleeve installation tool should be maneuverable to align a flow sleeve with each of the combustion can locations around the circumference of a gas turbine engine. The orientation of each combustion can depends on its position on the gas turbine. The angle and position for flow sleeve varies with each combustion can location. A flow sleeve installation tool has been conceived and is disclosed herein that is easily moved into angular alignment with each combustion can of a gas turbine engine. 
         [0009]    A flow sleeve removal tool has been conceived and is disclosed herein including: a shaft having an axis; a bracket attached to a first end region of the shaft, wherein the bracket includes a ring in a plane perpendicular to the axis of the shaft and a mount at the center of the bracket configured to receive the end region of the shaft, and wherein the ring is configured to abut and be releasably attached to an end of a flow sleeve of a gas turbine engine; a counter balance to the flow sleeve, wherein the counter balance is attached to a second end region of the shaft, and a cable connector mounted to the shaft between the counter balance and the flow sleeve, wherein the cable connector is configured to attach to a cable connected to an overhead support structure and the cable connector is at a position on the shaft at which the flow sleeve is substantially balances the counter weight, wherein an axis of the flow sleeve is coaxial with the axis of the shaft while the flow sleeve is attached to the bracket. 
         [0010]    The shaft may be a hollow metal rod and include a handle on the end of the shaft proximate to the counter balance. The mount for the cable may be a slidable collar on the shaft. A second cable connector may be mounted to the shaft, wherein a second cable is attached to the second cable connector and the overhead support structure to hold the shaft and flow sleeve in a certain angular position with respect to a horizontal plane. 
         [0011]    A flow sleeve removal tool and flow sleeve assembly comprising: a flow sleeve of a combustion can of a gas turbine engine, and a flow sleeve removal tool including: a shaft having an axis; a bracket attached to a first end region of the shaft, wherein the bracket includes a ring in a plane perpendicular to the axis of the shaft and a mount at the center of the bracket configured to receive the end region of the shaft, and wherein the ring is configured to abut and be releasably attached to an end of the flow sleeve; a counter balance to the flow sleeve, wherein the counter balance is attached to a second end region of the shaft, and a cable connector mounted to the shaft between the counter balance and the flow sleeve, wherein the cable connector is configured to attach to a cable connected to an overhead lift and the cable connector is at a position on the shaft at which the flow sleeve is substantially balances the counter weight, wherein an axis of the flow sleeve is coaxial with the axis of the shaft while the flow sleeve is attached to the bracket. 
         [0012]    A method has been conceived and is disclosed herein for inserting or removing a flow sleeve into or from a casing of a gas turbine engine, the method comprising: attaching a bracket of a flow sleeve installation tool to an end of the flow sleeve; aligning an axis of a shaft of the flow sleeve installation tool with an axis of the flow sleeve, wherein the shaft is attached to the bracket; attaching a cable connector coupled to the shaft to a cable supported by an overhead support structure; arranging the cable connector and a counterweight on the shaft such that the counterweight and flow sleeve are substantially balanced about the cable connector; 
         [0013]    maneuvering the shaft to move the axes of the shaft and the flow sleeve to be parallel to an axis of the opening in the casing configured to receive the flow sleeve, and after the maneuvering the shaft, sliding the flow sleeve with respect to the opening in the casing. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]      FIG. 1  is a side view of an industrial gas turbine engine with combustion cans; 
           [0015]      FIG. 2  is a cross sectional view of an exemplary combustion can; 
           [0016]      FIG. 3  is a side view of a flow sleeve extraction tool. 
           [0017]      FIG. 4  is a perspective view of the flow sleeve extraction tool extracting a combustion flow sleeve. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0018]      FIG. 1  shows an industrial gas turbine engine  10  which includes a compressor  12 , combustion cans  14  and a turbine  16 . The combustion cans  14  are each attached to an opening  33  on the casing  15  for the gas turbine engine. The combustion cans are arranged in a circular array around a center portion of the casing. 
         [0019]    Air enters the compressor through an intake duct  18 . Compressed air exits the compressor and is mixed with fuel in each of the combustion cans  14  wherein the mixture combusts and forms hot combustion gases which rotate the turbine  16 . The turbine drives the compressor to compress the air and produces power used to generate electricity or perform other work. Combustion gas exhausted from the turbine flows through an exhaust duct  20 . 
         [0020]    The industrial gas turbine engine  10  is enclosed in a housing  22 . The gas turbine sits on a concrete pad  24  or other support platform, and is supported by support brackets  26  between the pad and the gas turbine engine. An air filter housing and ducts is typically in front of the gas turbine engine and an exhaust duct housing is behind the engine. The area around a gas turbine engine may be limited due to the pad, support brackets and ducts. Tools used to remove and install flow sleeves should be compact to work in the confined space around the gas turbine engine. 
         [0021]      FIG. 2  is a cross-sectional side view of a combustion can  14  that includes a substantially cylindrical metal housing  28  secured to an annular flange section  30  of the casing  15  for the gas turbine engine. The combustion can  14  extends radially and axially outward from the casing. Each can has a different position on the perimeter of the casing. A cap  32  on the outer end  31  of the combustion can supports couplings to fuel conduits. The cap  32  is shown in  FIG. 1  but not  FIG. 2 . The cap is removed before the flow sleeve is removed. 
         [0022]    The end of the housing  28  opposite to the cap is fastened to an annular flange section  30  of the casing  15 . The annular flange section includes openings  33  that align with the open end of the housing. An annular flange  34  on the end of the housing seats on a ring surface  36  around the opening of the flange  30  of the casing. Bolts  38  extend through the flanges  30 ,  34  to secure the housing  38  to the casing. 
         [0023]    The housing  28  is fitted to the flange  30  after a flow sleeve  40  is inserted into the opening  33  of the casing. The housing slides over the flow sleeve. 
         [0024]    The flow sleeve is a generally cylindrical metal tube formed of thin sheet metal. The flow sleeve  40  extends from the outer end  31  of the housing  28  to a transition duct  42 . The duct  42  directs combustion gas to a first stage  44  of the turbine. 
         [0025]    The flow sleeve has openings to allow compressed air  46  from the compressor to pass through the flow sleeve and enter an annular passage between the flow sleeve and a combustion liner  48 . The flow liner  48  is a generally cylindrical tube that is within and coaxial with the flow sleeve. Compressed air and fuel mix within the flow liner to form combustion gases  50  that flow through the transition duct  42  to the first stage  44  of the turbine. 
         [0026]    The flow sleeve is generally about one and a half feet to three feet (0.5 to 1 meter(m)) in diameter and three to five feet (1 m to 1.5 m) in length. The weight of the flow sleeves is typically in a range of 60 to 200 pounds (0.5 to 2.8 kilograms (kg)). The size and weight of a flow sleeve are such that they may be installed and removed manually with the aid of tools. 
         [0027]    A flow sleeve installation and removal tool  60  has been inverted that includes a bracket  62  supported at one end of a shaft  64  and a counter weight  66  at on opposite end of the shaft. The bracket attaches to an end  31  ( FIG. 2 ) of a flow sleeve. The bracket may include a ring  68  with holes to receive fasteners, e.g. bolts  72 , that secure a clamp  74  to the ring. The ring is in a plane perpendicular to the axes of the shaft and flow sleeve. 
         [0028]    The clamp attaches the ring to the end  31  of the flow sleeve. Spokes  76  on the bracket connect the ring  68  to a center disc  78  which has a cylindrical recess  80  to receive an end of the shaft  64 . The recess  80  may be at the center of the ring and the bracket  62 . The recess may be threaded to receive and engage threads on the end of the shaft. 
         [0029]    The bolt  72  for each clamp  74  may be include a threaded end configured to engage a hole  82  ( FIG. 2 ) on an outer annular flange  84  of the flow sleeve. The bolt  72  extends through a hole  70  in the clamp and screws into the hole  82  of the flange. The blot may be tightened manually. The bolts and clamp secure the bracket  62  to the end  31  of the flow sleeve. 
         [0030]    The shaft  64  may be a hollow metal pipe having a length of two to five feet (0.6 m to 1.5 m). The thickness and strength of the shaft is sufficient to support a flow sleeve at one end of the shaft. 
         [0031]    The end of the shaft opposite to the bracket may include a handle  86 . The handle is configured to be held by the hands of a technician installing the flow sleeve. By manipulating the handle and the shaft, the technician moves the flow sleeve from a floor to the openings in the casing for the flow sleeve. Similarly, the handle is used by the technician to slide the flow sleeve out of the casing and position the removed flow sleeve on the floor. 
         [0032]    A counter weight  66  is on the shaft  64  near the handle  86 . The counter weight balances the flow sleeve mounted to the installation tool. The counter weight may have a mass (weight) substantially the same as the weight of the flow sleeve. For example, the mass of the counter weight may be 80 percent to 120 percent of the mass of the flow sleeve. The mass of the counter weight may be adjustable by adding or removing mass to the counter weight. The counter weight may also slide to different positions on the shaft to improve its function as a counter-balance to the flow sleeve. Once slid to the proper position, the counter weight is fixed to the shaft, such as by a thumb screw that extends from the counter weight and binds against the shaft. 
         [0033]    A slidable collar  88  on the shaft includes a hook or other cable connection  90  to receive a cable  92 , such as a chain or rope, that is attached to an overhead lift  94 , such as a crane or winch. The collar  88  forms a pivot about which the flow sleeve may be tilted and moved while attached to the flow sleeve installation tool. The collar may be slid along the shaft  64  such that the flow sleeve is balanced about the pivot by the counter weight  66 . A thumb screw  96  may secure the collar to the shaft to hold the collar at a desired position on the shaft and preventing the collar from sliding while the flow sleeve is being maneuvered. 
         [0034]    The overhead lift  94  may be movable in horizontal and vertical directions to move the flow sleeve installation tool and flow sleeve during the removal or installation of the flow sleeve. 
         [0035]    A second collar  98  on the shaft may be positioned proximate to the counter weight. The second collar may be connected to the lift (or to a second lift) by a second cable  100 . The technician will determine whether to connect either or both of the collars  88 ,  98  to the lift depending on the circumstances of each installation or removal of a flow sleeve. 
         [0036]      FIG. 4  illustrates a flow sleeve  40  being installed into an opening  33  for a combustion can in the casing  15  of a gas turbine engine. The annular bracket  62  of the flow sleeve installation tool is attached to the annular flange  84  at the outer end of the flow sleeve  40 . Clamps  74  secure the bracket to the flange. 
         [0037]    The end of the shaft  64  of the flow sleeve installation tool  60  is inserted and attached to the center disc  78  of the bracket  62  of the tool. When attached to the bracket and the bracket is attached to the flow sleeve, the shaft  64  is aligned, i.e., coaxial, with the axis  102  of the flow sleeve. The alignment assists in balancing the counter weight  66  and the flow sleeve. 
         [0038]    By balancing the flow sleeve and the counter weight, the flow sleeve and counter weight can be supported at the collar  88  by the cable  92  and the overhead lift  94 . The balance allows the flow sleeve to be easily pivoted about the collar  88  by a technician moving the handle  86 . 
         [0039]    By pivoting the flow sleeve  40  about the collar  88 , the flow sleeve can be moved to an angular position that is parallel to an axis  102  of the combustion can that is to receive the flow sleeve. The flow sleeve may be moved in horizontal and vertical directions by moving the overhead lift  94 . By moving the overhead lift and using the handle  86  to pivot the flow sleeve installation tool  60 , the flow sleeve  40  can be moved into alignment with the opening  33  to receive the flow sleeve. 
         [0040]    Once the flow sleeve installation tool  60  has been manipulated to align the flow sleeve  40  with the opening  33 , a second cable  92  may be attached to the second collar  98  and the overhead lift. By attaching the second cable, the angular position with respect to a horizontal plane can be fixed to hold the flow sleeve in angular alignment with the opening of the turbine casing. 
         [0041]    Once the flow sleeve is aligned with the opening of the turbine casing, the flow sleeve may be inserted into the opening  33  by releasing the thumb screw on the collar  88  and allowing the shaft  64  to slide with respect to the collar. As the shaft slides through the collar, the flow sleeve slides into the opening  33  of the gas turbine engine. Similarly, a flow sleeve can be removed after the flow installation tool is attached by allowing the shaft to slide through the collar as the flow sleeve slides out of the casing. In addition to sliding laterally, the shaft may rotate with respect to the collar to cause the flow sleeve to rotate as it slides in or out of the turbine casing. 
         [0042]    The flow sleeve installation tool  60  is a safe, compact and inexpensive. The tool allows the weight of the flow sleeve  40  to be borne by an overhead lift in a manner than allows the sleeve to be pivoted up, down and sideways. The pivoting enables a technician to easily place the flow sleeve at an angle aligned with an axis of a combustion can. 
         [0043]    While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiment, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.