FABRIC FOREIGN MATERIAL EXCLUSION SYSTEM

A foreign material exclusion system for positioning within a casing of a turbine to catch any foreign material during maintenance of the turbine. The foreign material exclusion system may include a fabric sleeve with a semicircular shape and a number of poles attached to the sleeve to maintain the sleeve in place within the turbine casing.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority pursuant to 35 U.S.C. 119(a) to Polish Application No. P.444688, filed Apr. 28, 2023, which application is incorporated herein by reference in its entirety.

TECHNICAL FIELD

The present application and the resultant patent relate generally to turbomachinery such as gas turbines and steam turbines and more particularly relate to a fabric foreign material exclusion system to capture foreign material such as turbine pins and other objects that may become lost during removal and replacement of turbine blades or other types of procedures.

BACKGROUND

A gas turbine engine conventionally includes a compressor for compressing ambient air and a combustor for mixing the flow of air with a flow of fuel to generate hot combustion gases. A turbine receives the flow of hot combustion gases and extracts energy therefrom for powering the compressor and for producing output power for an external load such as an electrical generator and the like. Turbine components such as turbine buckets and blades positioned along the hot gas path are subject to not only high combustion temperatures but also different types of dynamic forces. Given such, these hot gas path components may be replaced and/or refurbished on a periodic basis to ensure efficient performance.

Turbine blades may have a number of relatively small components such as seal pins and damper pins attached thereto. These relatively small components must be removed with the turbine blades. If a pin or other type of component were to be misplaced and left inside the turbine, the component could cause catastrophic damage upon the restart of the turbine.

Current foreign material exclusion systems may use a large tarp that is positioned under the rotating turbine components to catch foreign material such as the pins and the like. The tarp may be secured by taping the tarp to the casing. The tarp, however, tends to bunch up under the rotating components and may be snagged and/or may slip under the rotating components. Such snagging or slipping may allow a pin or other type of foreign material to escape into the turbine, particularly when removing the tarp. Given such, foreign material remains a significant issue during turbine maintenance and other procedures.

SUMMARY

The present application and the resultant patent thus provide a foreign material exclusion system for positioning within a casing of a turbine to catch any foreign material during maintenance of the turbine. The foreign material exclusion system may include a fabric sleeve with a semicircular shape and a number of poles attached to the sleeve to maintain the sleeve in place within the turbine casing.

The present application and the resultant patent further provide a method of inserting a foreign material exclusion system into a casing of a turbine about a number of stages thereof. The method may include the steps of sliding a sleeve between the casing and the number of stages, inserting one or more poles into the sleeve, attaching the sleeve to the casing with one or more sled hooks, and attaching one or more horizontal joint frame plates to the sleeve.

The present application and the resultant patent further provide a foreign material exclusion system for positioning within a casing of a turbine to catch any foreign material during maintenance of the turbine. The foreign material exclusion system may include a fabric sleeve with a semicircular shape, a number of channels formed therein, and a horizontal joint frame plate. A number of poles may be positioned within the channels to maintain the sleeve in place within the turbine casing.

DETAILED DESCRIPTION

Referring now to the drawings, in which like numerals refer to like elements throughout the several views,FIG.1shows a schematic diagram of a gas turbine engine10as may be used herein. The gas turbine engine10may include a compressor15. The compressor15compresses an incoming flow of air20. The compressor15delivers the compressed flow of air20to a number of combustor cans25. The combustor cans25mix the compressed flow of air20with a pressurized flow of fuel30and ignite the mixture to create a flow of hot combustion gases35. Although only a single combustor can25is shown, the gas turbine engine10may include any number of combustor cans25positioned in a circumferential array and the like. Alternatively, the combustor25may be an annular combustor. The flow of combustion gases35is in turn delivered to a turbine40. The flow of combustion gases35drives the turbine40to produce mechanical work. The mechanical work produced in the turbine40drives the compressor15via a rotor shaft45and an external load50such as an electrical generator and the like.

The gas turbine engine10may use natural gas, various types of syngas, liquid fuels, and/or other types of fuels and blends thereof. The gas turbine engine10may be any one of a number of different gas turbine engines offered by General Electric Company of Schenectady, New York, including, but not limited to, those such as a 7-series or a 9-series heavy duty gas turbine engine and the like. The gas turbine engine10may be part of a simple cycle or a combined cycle power generation system or other types of generation systems. The gas turbine engine10may have different configurations and may use other types of components. Other types of gas turbine engines also may be used herein. Multiple gas turbine engines, other types of turbines, and other types of power generation equipment also may be used herein together.

FIG.2is a partial sectional view of the turbine40. The turbine40includes a number of stages52. Generally described, each stage52includes a stationary row54of stator vanes56and a rotating row58of turbine blades60. In this example, three stages52are shown, a first stage, a second stage, and a third stage. The turbine blades60in each row58are spaced circumferentially about, and extend radially outward from, a rotor disk62. Each rotor disk62is coupled to the rotor shaft45. A turbine casing64extends circumferentially about the stator vanes56. The stator vanes56are each coupled to the turbine casing64and each stator vane56extends radially inward from the casing64towards the rotor shaft45. A hot combustion gas path66is defined between the turbine casing64and each rotor disk62.

FIG.3shows an example of a turbine blade60of the turbine40. The turbine blade60may include a shank68, a dovetail70, a platform72, and an airfoil74. The dovetail70secures the turbine blade60to a periphery of the rotor disk62. The platform72defines an inward flow boundary for the combustion gases35flowing through the hot combustion gas path66. A damper pin76may be located along one axial edge (or slash face)78adjacent to (i.e., radially inward of) the platform72. Specifically, the damper pin76maybe located in an elongated groove80that extends along the slash face78of the turbine blade60. The damper pin76frictionally dissipates vibratory energy and reduces corresponding amplitude of vibration. A similar damper pin76may be located between each adjacent pair of turbine blades60. Other types of pins such as seal pins and the like also may be used herein. During the deblading process and other types of maintenance, the pins76and the like may become a foreign material82capable of damage to the turbine40if not accounted for and removed.

FIGS.4and5show an example of a foreign material exclusion system100as may be described herein. The foreign material exclusion system100may include a sleeve110. The sleeve110may have a substantial semicircular shape120. Specifically, the sleeve110may be sized and shaped to fit within a lower half of the casing64. The sleeve110may extend across several stages52. The sleeve110may be made out of a fabric130. The fabric130may include woven plastic mesh, nonwoven synthetic material, impregnated resins, natural porous fibers such as cotton, heavy duty waterproof and temperature resistant material, or any flexible, formable surface covering, and similar types of materials and blends thereof.

Generally described, the sleeve110may include a base wall140extending from a first end150to a second end160, a first sidewall170, and a second sidewall180. The base wall140and the sidewalls170,180may be sown together to form the sleeve110. Alternatively, zippers (clasp lockers) and the like also may be used to connect the walls. The sidewalls170,180may have channels190formed in an inner edge200and an outer edge210thereof. The channels190may be sized for the elongated poles220to be positioned therein. The elongated poles220may be curved in the semicircular shape120and serve to provide rigidity to the sleeve110. The elongated poles220may be made out of any substantially rigid material such as plastics, steel or metal such as aluminum and titanium, carbon fiber, fiberglass, combinations thereof, and the like. As is shown inFIG.7and as will be described in more detail below, the poles220of the sleeve110may be tensioned and held in place by a number of rigid fiber collets230and the like. Other types of tensioning devices may be used herein. Other components and other configurations may be used herein.

The first and second ends150,160of the base wall140may have magnets240and the like sewn or otherwise positioned therein. The magnets240are attracted to the metal of the lower half of the casing64to keep the sleeve110in place. Alternatively, different types of weights and the like also may be used. The first and second ends150,160of the base wall140also may be held in place by a number of sled hooks250. As is shown inFIG.8and described in more detail below, the sled hooks250pin the fabric130into position within the casing64along the ends150,160of the base wall140. The sled hooks250may be sized to accommodate specific shroud hook geometry and the like of a predetermined stage. The sled hooks250may capture the sleeve110to the circumference of the casing64via the poles220and the like.

The first and second ends150,160of the base wall140may be covered by a horizontal joint frame plate260. The horizontal joint frame plate260may be sized and shaped to ensure that the horizontal joint of the casing64is enclosed. The horizontal joint frame plate260may include a pair of flanges270that extend on either side of the stages52. The horizontal joint frame plate260also may include a number of pole apertures280for the elongated poles220to extend therethrough. The elongated poles220aid in maintaining the horizontal joint frame plate260in position. Other components and other configurations may be used herein.

In use as is shown inFIG.8, the foreign material exclusion system100may be slid into place about the lower half of the casing64beneath rows58of the turbine blades60. Specifically, the custom fit sleeve110may be positioned into place, the elongated poles220may be positioned within the channels190, and the elongated poles220may be tensioned via the rigid fiber collets230. The elongated poles220may provide the tight fit of the fabric130of the sleeve110to the casing64. Given such, the tight fit avoids bunching of the fabric130. The magnets240sewn in on both ends150,160of the sleeve110hold the sleeve110in position and enable optimal folding of the fabric130when removing the sleeve110from the casing64. This optimal folding ensures that any foreign material that fell into the sleeve110during the procedure is contained and safely removed. The horizontal joint frame plates260on the horizontal joints of the casing64keep the fabric130in place and close off all possible foreign material pathways about the ends thereof. Likewise, the sled hooks250ensure the proper guidance of the fabric130of the sleeve110into position.

The use of the fabric130for the sleeve110of the foreign material exclusion system100thus provides a custom fit that may be resistant of wear, tear, and heat. The custom fit thus provides maximum protection from foreign material entrance into the turbine area. The use of the elongated poles220in the semicircular shape120ensures that the sleeve110maintains the correct position with respect to the curvature of the casing64. The foreign material exclusion system100thus reduces the opportunity for foreign object damage during hot gas path inspection, deblading, and other procedures.

Further aspects of the invention are provided by the subject matter of the following clauses:1. A foreign material exclusion system for positioning within a casing of a turbine to catch any foreign material during maintenance of the turbine, comprising a sleeve with a semicircular shape; the sleeve comprising a fabric; and a plurality of poles attached to the sleeve to maintain the sleeve in place within the turbine casing.2. The foreign material exclusion system of any preceding clause, wherein the sleeve comprises a base wall, a first sidewall, and a second sidewall.3. The foreign material exclusion system of any preceding clause, wherein the first sidewall and the second sidewall comprise a plurality of channels to accommodate the plurality of poles.4. The foreign material exclusion system of any preceding clause, wherein the first sidewall and the second sidewall comprise an inner edge and an outer edge and wherein the inner edge and the outer edge both accommodate one of the plurality of channels therein.5. The foreign material exclusion system of any preceding clause, wherein the base wall comprises a first end and a second end.6. The foreign material exclusion system of any preceding clause, wherein the first end and the second end comprises a plurality of magnets therein.7. The foreign material exclusion system of any preceding clause, wherein the first end and the second end comprise one or more sled hooks thereon.8. The foreign material exclusion system of any preceding clause, wherein the one or more sled hooks are sized for a predetermined stage of the turbine.9. The foreign material exclusion system of any preceding clause, wherein the first end and the second end comprise a horizontal joint frame plate thereon.10. The foreign material exclusion system of any preceding clause, wherein the horizontal joint frame plate comprises a pair of flanges thereon.11. The foreign material exclusion system of any preceding clause, wherein the horizontal joint frame plate comprises a plurality of pole apertures sized to accommodate the plurality of poles.12. The foreign material exclusion system of any preceding clause, wherein the base wall, the first sidewall, and the second sidewall are sewn or zippered together.13. The foreign material exclusion system of any preceding clause, wherein the plurality of poles each comprise a rigid fiber collet for tensioning.14. The foreign material exclusion system of any preceding clause, wherein the fabric comprises natural or synthetic materials.15. A method of inserting a foreign material exclusion system into a casing of a turbine about a number of stages thereof, comprising: sliding a sleeve between the casing and the number of stages; inserting one or more poles into the sleeve; attaching the sleeve to the casing with one or more sled hooks; and attaching one or more horizontal joint frame plates to the sleeve.16. A foreign material exclusion system for positioning within a casing of a turbine to catch any foreign material during maintenance of the turbine, comprising: a sleeve with a semicircular shape; the sleeve comprising a fabric; the sleeve comprising a plurality of channels therein; a plurality of poles positioned within the plurality of channel to maintain the sleeve in place within the turbine casing; and a horizontal joint frame plate positioned about the sleeve.17. The foreign material exclusion system of any preceding clause, wherein the sleeve comprises a plurality of magnets therein.18. The foreign material exclusion system of any preceding clause, wherein the sleeve comprises one or more sled hooks thereon.19. The foreign material exclusion system of any preceding clause, wherein the plurality of poles each comprise a rigid fiber collet for tensioning.20. The foreign material exclusion system of any preceding clause, wherein the fabric comprises natural or synthetic materials.