US20040043703A1 - Apparatus and method of removing abradable material from a turbomachine fan containment case - Google Patents
Apparatus and method of removing abradable material from a turbomachine fan containment case Download PDFInfo
- Publication number
- US20040043703A1 US20040043703A1 US10/064,896 US6489602A US2004043703A1 US 20040043703 A1 US20040043703 A1 US 20040043703A1 US 6489602 A US6489602 A US 6489602A US 2004043703 A1 US2004043703 A1 US 2004043703A1
- Authority
- US
- United States
- Prior art keywords
- containment case
- fan containment
- interior surface
- rotation
- fan
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24C—ABRASIVE OR RELATED BLASTING WITH PARTICULATE MATERIAL
- B24C3/00—Abrasive blasting machines or devices; Plants
- B24C3/32—Abrasive blasting machines or devices; Plants designed for abrasive blasting of particular work, e.g. the internal surfaces of cylinder blocks
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24C—ABRASIVE OR RELATED BLASTING WITH PARTICULATE MATERIAL
- B24C3/00—Abrasive blasting machines or devices; Plants
- B24C3/32—Abrasive blasting machines or devices; Plants designed for abrasive blasting of particular work, e.g. the internal surfaces of cylinder blocks
- B24C3/325—Abrasive blasting machines or devices; Plants designed for abrasive blasting of particular work, e.g. the internal surfaces of cylinder blocks for internal surfaces, e.g. of tubes
Definitions
- the present invention generally relates to fan containment assemblies for turbomachinery, such as gas turbine engines. More particularly, this invention relates to an automated apparatus and method for removing an abradable material for a fan containment assembly.
- Gas turbine engines generally operate on the principle of compressing air within a compressor section of the engine, and then delivering the compressed air to the combustion section of the engine where fuel is added to the air and ignited. Afterwards, the resulting combustion mixture is delivered to the turbine section of the engine, where a portion of the energy generated by the combustion process is extracted by a turbine to drive the engine compressor.
- High bypass turbofan engines widely used for high performance aircraft which operate at subsonic speeds, have a large fan placed at the front of the engine to produce greater thrust and reduce specific fuel consumption. The fan compresses the incoming air, a portion of which is then delivered to the combustion chamber, though a larger portion is bypassed to the rear of the engine to generate additional engine thrust.
- the fan is circumscribed by a fan containment case such that the case is immediately adjacent the tips of the fan blades.
- the containment case serves to channel incoming air through the fan so as to ensure that the bulk of the air entering the engine will be compressed by the fan.
- a small portion of the air is able to bypass the fan blades through a radial gap present between the fan blade tips and the containment case.
- engine efficiency can be increased by limiting the amount of air which is able to bypass the fan blades through this gap. Accordingly, the fan and containment case are manufactured to close tolerances in order to minimize the gap.
- the fan blades may rub the containment case as a result of a hard landing or a hard maneuver of the aircraft. Any rubbing contact between the fan blade tips and the containment case will abrade the tips of the rotors, tending to further increase the gap between the containment case and blade tips, thereby reducing engine efficiency.
- the fan is circumscribed by a fan containment case such that the case is immediately adjacent the tips of the fan blades.
- the containment case serves to channel incoming air through the fan so as to ensure that the bulk of the air entering the engine will be compressed by the fan.
- the fan and containment case are manufactured to close tolerances in order to minimize the gap.
- manufacturing tolerances differing rates of thermal expansion and dynamic effects limit the extent to which this gap can be reduced.
- the fan blades may rub the containment case as a result of a hard landing or a hard maneuver of the aircraft. Any rubbing contact between the fan blade tips and the containment case will abrade the tips of the rotors, tending to further increase the gap between the containment case and blade tips, thereby reducing engine efficiency.
- a common technique for removing the abradable material is performed with handheld tools, such as an air chisel, after which sandpaper is used to achieve a smooth surface finish. While suitable for use on steel fan cases, air chisels are too aggressive for use on engines with aluminum cases. Aluminum fan cases must be removed from the fan frame, stripped of gearboxes, wire harnesses, controls, etc., and then centered on a turning machine to remove the old abradable material. Any damage that may occur to the base metal must be repaired before applying and bonding the new abradable material. The removal process can be time consuming and expensive, and requires a large maintenance facility to which at least the front of the engine must be transported for disassembly. Due to the special equipment required to perform the machining operation, a limited number of facilities are available for removing fan case abradable material. As a result, additional costs, scheduling and transport problems are common.
- the present invention provides an apparatus and method for removing an abradable material from an interior surface of a fan containment case, without requiring removal of the fan containment case from its engine, e.g., a high-bypass gas turbine engine.
- the apparatus of this invention generally includes a frame, and means rotatably mounted to the frame for spraying an erosion media in a substantially radial direction relative to a horizontal axis of rotation of the spraying means.
- the erosion media impacts the abradable material on the interior surface of the fan containment case while the spraying means is positioned within the fan containment case adjacent the abradable material.
- the apparatus further includes means rotatably mounted to the frame with the spraying means for retrieving the erosion media after impacting the abradable material.
- a method made possible with the apparatus of this invention generally comprises the steps of adjusting the elevation of the spraying means and centering the horizontal axis of rotation thereof with the fan containment case to position the spraying means adjacent the abradable material on the interior surface of the fan containment case.
- the erosion media is then sprayed with the spraying means in a substantially radial direction relative to the horizontal axis of rotation of the spraying means, such that the erosion media impacts and erodes the abradable material on the interior surface of the fan containment case.
- the spraying means is rotated about the horizontal axis of rotation thereof so that the erosion media is sprayed at the abradable material along the entire circumference of the fan containment case.
- the erosion media is retrieved after being sprayed and impacted against the abradable material.
- a significant advantage of this invention is that the apparatus is capable of removing the abradable material from a fan containment case without requiring removal of the case from an engine. Instead, only the fan blades need be removed to gain access to the interior surface of the case.
- Another advantage of the invention is that the apparatus provides a means by which the spraying means is self-centered with respect to the interior surface of the fan containment case, and the operation of the spraying means can be controlled to follow a specific path along the inner diameter of the fan containment case. As such, the apparatus requires minimal setup, and can be operated in an automated mode without further human supervision.
- the apparatus is capable of removing substantially all of the abradable material in roughly a single rotation of the spraying means about its horizontal axis of rotation. With the use of appropriate abradable material and spray pressures, this operation can be completed in about one hour without damaging the substrate beneath the abradable material.
- FIG. 1 is a side view of an apparatus for removing abradable material from a fan containment case in accordance with a preferred embodiment of this invention.
- FIGS. 2, 3, 4 and 5 are a top view, front end view, back end view, and perspective view, respectively, of the apparatus of FIG. 1.
- FIG. 6 is a perspective view of a blast head shown mounted to the apparatus of FIG. 1.
- FIGS. 1 through 5 represent an apparatus 10 for removing an abradable material in accordance with a preferred embodiment of the invention.
- the apparatus 10 is particularly adapted for removing an abradable material from the blade containment case of a turbomachine, such as the fan containment case of a high bypass turbofan engine.
- a turbomachine such as the fan containment case of a high bypass turbofan engine.
- high bypass turbofan engines have a fan section within which a fan formed by a number of fan blades is mounted to a hub.
- a fan section 12 is represented in phantom in FIG. 1, and includes a fan containment case 14 that circumscribes the fan (shown removed), and whose radially inward surface has a channel 16 containing an abradable material.
- Suitable materials for the abradable material include various lightweight materials known and used in the prior art, including composite materials such as an epoxy filled with hollow glass beads.
- the apparatus 10 of this invention is adapted to remove the abradable material from the case 14 to permit the application of a new layer of abradable material. While the invention can be used to remove abradable material from containment cases formed of a variety of materials, including steel, the invention is particularly well suited for use on aluminum cases that are more prone to damage during removal of the abradable material by conventional methods.
- the apparatus 10 is able to remove the abradable material while the fan containment case 14 remains mounted to the engine.
- the apparatus 10 is shown as comprising a frame assembly 20 having a base 22 , platform 24 and legs 26 pivotably connected to both the base 22 and platform 24 .
- a vertical actuator 28 is mounted to the base 22 and connected to the platform 24 to raise and lower the platform 24 relative to the base 22 .
- the base 22 is shown as being equipped with wheels 29 that enable the apparatus 10 to be moved and positioned in front of the fan section 12 .
- the wheels 29 are preferably equipped with wheel locks (not shown) of any conventional design to prevent movement of the apparatus 10 once positioned.
- the blast head 40 delivers an erosion media (not shown) for the purpose of removing the abradable material from the fan containment case 14 .
- the orientation (tilt) of the blast head 40 is adjusted with a tilt adjustor 46 , also mounted to the articulating arms 42 .
- the electric motor 34 With the electric motor 34 , the entire assembly—comprising the shaft assembly 30 , radial arm 38 , arms 42 and blast head 40 , etc.—can be caused to rotate about the axis of the shaft assembly 30 , which is oriented horizontally in view of the orientation of the engine fan section 12 .
- the blast head 40 can be caused to follow the inner circumference of the fan case 14 while spraying the erosion media in a generally radial direction, such that the erosion media impacts the abradable material located on the interior surface of the fan containment case 14 , as represented in FIG. 1.
- FIGS. 1 through 5 Also shown in FIGS. 1 through 5 is a chuck assembly 48 mounted to a housing 32 that supports the shaft assembly 30 .
- the chuck assembly 48 is shown as comprising three two-bar arm assemblies 50 , which as shown in FIG. 1 are adapted to engage the fan containment case 14 and center the shaft assembly 30 with the centerline of the fan section 12 .
- three equiangularly-spaced arm assemblies 50 are preferred, though it is foreseeable that a different number of arms could be used.
- the arm assemblies 50 are articulated in unison through rods 52 connected to a collar 54 mounted with bearings to the shaft assembly 30 .
- the chuck assembly 48 has a horizontal central axis that substantially coincides with the axis of rotation of the shaft assembly 30 .
- An actuator 56 is coupled to the collar 54 to move the collar 54 axially along a given length of the shaft assembly 30 , causing the arm assemblies 50 to pivot in unison toward or away from the axis of rotation of the shaft assembly 30 .
- the distal end 58 of each arm assembly 50 is adapted to engage the interior surface of the fan containment case 14 , and is equipped with a clamp 60 for gripping the case 14 with the distal end 58 .
- FIGS. 1 and 2 an actuator 62 is shown with which the shaft assembly 30 —and therefore simultaneously the blast head 40 and chuck assembly 48 —can be moved axially, i.e., parallel to the axis of rotation of the shaft assembly 30 . Consequently, the blast head 40 can be introduced into the fan section 12 , positioned in the cross-sectional plane of the case 14 containing the abradable material to perform the removal operation, and later retracted from the fan section 12 at the completion of the operation. Simultaneously with the introduction of the blast head 40 in the fan section 12 , the arm assemblies 50 are moved toward the fan section 12 .
- the blast head 40 represented in FIGS. 1 through 5 is shown in greater detail in FIG. 6.
- the blast head 40 can be seen to comprise a containment enclosure 64 for containing the erosion media sprayed through a spray head 66 disposed in a wall of the enclosure 64 .
- the outer surface 68 of the containment enclosure 64 is contoured to correspond to the radius of the fan containment case 14 , and is equipped with a rubber or brush seal (not shown) to provide a sealing action with the interior surface of the fan containment case 14 .
- the erosion media is delivered to the spray head 66 through a supply hose 70 , and retrieved from the enclosure 64 through a pair of hoses 72 attached to opposite sides of the enclosure 64 .
- the erosion media is retrieved from the containment enclosure 64 after the erosion media is sprayed from the spray head 66 and has impacted the abradable material on the interior surface of the fan containment case 14 . Thereafter, the spent erosion media containing particles of the abradable material may be discarded, though in a preferred embodiment the erosion media is separated from particles of the abradable material and reused.
- spray heads 66 of various designs may be used, a preferred spray head 66 is equipped with multiple nozzles, preferably three as shown, that rotate together about the axis along which the media is sprayed.
- a blast head 40 equipped with the preferred spray head 66 and media retrieval and reclamation system particularly suitable for use with this invention is the MPC Series of machines available from Abrasive Blast Systems, Inc., of Abilene, Kans.
- An erosion material found to be suitable for use with the apparatus 10 of this invention is a plastic bead material formed of Type II urea formaldehyde thermoset per Mil-P-85291, and therefore commercially available from a number of sources.
- a suitable particle size for the Mil-P-85291 media is about twenty to about thirty mesh, though smaller and larger particle sizes could be used.
- suitable operating parameters for the blast head 40 include an adjustable supply pressure of about 50 to about 80 psi (about 3.5 to about 5.5 bar), such as about 65 psi (about 4.5 bar).
- the volumetric airflow rate from the enclosure 64 is preferably slightly higher than the flowrate to the enclosure 64 to promote a vacuuming effect for reclaiming the media from the enclosure 64 .
- the apparatus 10 is capable of being operated within minimal supervision by an operator.
- the apparatus 10 is preferably equipped with controls that cause the shaft assembly 30 to rotate and the blast head 40 to spray the media according to predetermined settings.
- Automatic safety stops are preferably provided to stop the operation of the blast head 40 if the shaft assembly 30 stops rotating.
- a control unit 74 is seen mounted to the platform 24 by which the rotational speed of the blast head 40 (through the shaft assembly 30 ) is controlled.
- a pendant control 76 with switches, etc., for controlling the operation of the chuck assembly 48 and actuators 28 , 56 and 62 .
- the apparatus 10 of this invention can be used to remove abradable material from an interior surface of a fan containment case 14 while the case 14 remains mounted to a high bypass turbofan engine.
- the fan blades Prior to the operation, the fan blades are removed from the engine, the platform 24 is raised with the vertical actuator 28 to align the axis of the shaft assembly 30 (and therefore the axis of the chuck assembly 48 ) with the centerline of the fan section 12 .
- the blast head 40 and arm assemblies 50 can then be introduced into the case 14 by extending the actuator 62 .
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Structures Of Non-Positive Displacement Pumps (AREA)
Abstract
Description
- 1. Field of the Invention
- The present invention generally relates to fan containment assemblies for turbomachinery, such as gas turbine engines. More particularly, this invention relates to an automated apparatus and method for removing an abradable material for a fan containment assembly.
- 2. Description of the Related Art
- Gas turbine engines generally operate on the principle of compressing air within a compressor section of the engine, and then delivering the compressed air to the combustion section of the engine where fuel is added to the air and ignited. Afterwards, the resulting combustion mixture is delivered to the turbine section of the engine, where a portion of the energy generated by the combustion process is extracted by a turbine to drive the engine compressor. High bypass turbofan engines, widely used for high performance aircraft which operate at subsonic speeds, have a large fan placed at the front of the engine to produce greater thrust and reduce specific fuel consumption. The fan compresses the incoming air, a portion of which is then delivered to the combustion chamber, though a larger portion is bypassed to the rear of the engine to generate additional engine thrust.
- The fan is circumscribed by a fan containment case such that the case is immediately adjacent the tips of the fan blades. The containment case serves to channel incoming air through the fan so as to ensure that the bulk of the air entering the engine will be compressed by the fan. However, a small portion of the air is able to bypass the fan blades through a radial gap present between the fan blade tips and the containment case. Because the air compressed by the fan blades is used to generate thrust and feed the turbine section of the engine, engine efficiency can be increased by limiting the amount of air which is able to bypass the fan blades through this gap. Accordingly, the fan and containment case are manufactured to close tolerances in order to minimize the gap. However, manufacturing tolerances, differing rates of thermal expansion and dynamic effects limit the extent to which this gap can be reduced. Furthermore, during the normal operation of an aircraft turbofan engine, the fan blades may rub the containment case as a result of a hard landing or a hard maneuver of the aircraft. Any rubbing contact between the fan blade tips and the containment case will abrade the tips of the rotors, tending to further increase the gap between the containment case and blade tips, thereby reducing engine efficiency. The fan is circumscribed by a fan containment case such that the case is immediately adjacent the tips of the fan blades. The containment case serves to channel incoming air through the fan so as to ensure that the bulk of the air entering the engine will be compressed by the fan. However, a small portion of the air is able to bypass the fan blades through a radial gap present between the fan blade tips and the containment case. Because the air compressed by the fan blades is used to generate thrust and feed the turbine section of the engine, engine efficiency can be increased by limiting the amount of air which is able to bypass the fan blades through this gap. Accordingly, the fan and containment case are manufactured to close tolerances in order to minimize the gap. However, manufacturing tolerances, differing rates of thermal expansion and dynamic effects limit the extent to which this gap can be reduced. Furthermore, during the normal operation of an aircraft turbofan engine, the fan blades may rub the containment case as a result of a hard landing or a hard maneuver of the aircraft. Any rubbing contact between the fan blade tips and the containment case will abrade the tips of the rotors, tending to further increase the gap between the containment case and blade tips, thereby reducing engine efficiency.
- In view of the above, it is well known in the art to cover the portion of the containment case adjacent the blade tips with an abradable material, such that the abradable material will sacrificially abrade away when rubbed by the fan blades. Inherently, as the abradable material is removed, the gap between the blade tips and the surface of the abradable material will increase, necessitating removal and replacement of the abradable material to maintain desirable aerodynamic efficiencies associated with a smooth abradable surface and a small gap between the abradable surface and the fan blade tips. Restoration of the abradable material also becomes necessary if damage has occurred from impacts with foreign objects.
- A common technique for removing the abradable material is performed with handheld tools, such as an air chisel, after which sandpaper is used to achieve a smooth surface finish. While suitable for use on steel fan cases, air chisels are too aggressive for use on engines with aluminum cases. Aluminum fan cases must be removed from the fan frame, stripped of gearboxes, wire harnesses, controls, etc., and then centered on a turning machine to remove the old abradable material. Any damage that may occur to the base metal must be repaired before applying and bonding the new abradable material. The removal process can be time consuming and expensive, and requires a large maintenance facility to which at least the front of the engine must be transported for disassembly. Due to the special equipment required to perform the machining operation, a limited number of facilities are available for removing fan case abradable material. As a result, additional costs, scheduling and transport problems are common.
- Accordingly, it would be desirable if an improved technique were available by which the abradable material of a fan containment case could be removed without requiring removal of the fan case from the engine, such that restoration can be performed in the field.
- The present invention provides an apparatus and method for removing an abradable material from an interior surface of a fan containment case, without requiring removal of the fan containment case from its engine, e.g., a high-bypass gas turbine engine. The apparatus of this invention generally includes a frame, and means rotatably mounted to the frame for spraying an erosion media in a substantially radial direction relative to a horizontal axis of rotation of the spraying means. The erosion media impacts the abradable material on the interior surface of the fan containment case while the spraying means is positioned within the fan containment case adjacent the abradable material. The apparatus further includes means rotatably mounted to the frame with the spraying means for retrieving the erosion media after impacting the abradable material. Also provided is means mounted to the frame for centering the horizontal axis of rotation of the spraying means relative to the interior surface of the fan containment case, means for adjusting together the elevation of a horizontal central axis of the centering means and the horizontal axis of rotation of the spraying means relative to the frame, and means for positioning the spraying means adjacent the interior surface of the fan containment case.
- A method made possible with the apparatus of this invention generally comprises the steps of adjusting the elevation of the spraying means and centering the horizontal axis of rotation thereof with the fan containment case to position the spraying means adjacent the abradable material on the interior surface of the fan containment case. The erosion media is then sprayed with the spraying means in a substantially radial direction relative to the horizontal axis of rotation of the spraying means, such that the erosion media impacts and erodes the abradable material on the interior surface of the fan containment case. In addition, the spraying means is rotated about the horizontal axis of rotation thereof so that the erosion media is sprayed at the abradable material along the entire circumference of the fan containment case. At the same time, the erosion media is retrieved after being sprayed and impacted against the abradable material.
- In view of the above, it can be seen that a significant advantage of this invention is that the apparatus is capable of removing the abradable material from a fan containment case without requiring removal of the case from an engine. Instead, only the fan blades need be removed to gain access to the interior surface of the case. Another advantage of the invention is that the apparatus provides a means by which the spraying means is self-centered with respect to the interior surface of the fan containment case, and the operation of the spraying means can be controlled to follow a specific path along the inner diameter of the fan containment case. As such, the apparatus requires minimal setup, and can be operated in an automated mode without further human supervision. In a preferred embodiment, the apparatus is capable of removing substantially all of the abradable material in roughly a single rotation of the spraying means about its horizontal axis of rotation. With the use of appropriate abradable material and spray pressures, this operation can be completed in about one hour without damaging the substrate beneath the abradable material.
- Other objects and advantages of this invention will be better appreciated from the following detailed description.
- FIG. 1 is a side view of an apparatus for removing abradable material from a fan containment case in accordance with a preferred embodiment of this invention.
- FIGS. 2, 3,4 and 5 are a top view, front end view, back end view, and perspective view, respectively, of the apparatus of FIG. 1.
- FIG. 6 is a perspective view of a blast head shown mounted to the apparatus of FIG. 1.
- FIGS. 1 through 5 represent an
apparatus 10 for removing an abradable material in accordance with a preferred embodiment of the invention. Theapparatus 10 is particularly adapted for removing an abradable material from the blade containment case of a turbomachine, such as the fan containment case of a high bypass turbofan engine. As known in the art, high bypass turbofan engines have a fan section within which a fan formed by a number of fan blades is mounted to a hub. Afan section 12 is represented in phantom in FIG. 1, and includes afan containment case 14 that circumscribes the fan (shown removed), and whose radially inward surface has achannel 16 containing an abradable material. Suitable materials for the abradable material include various lightweight materials known and used in the prior art, including composite materials such as an epoxy filled with hollow glass beads. Theapparatus 10 of this invention is adapted to remove the abradable material from thecase 14 to permit the application of a new layer of abradable material. While the invention can be used to remove abradable material from containment cases formed of a variety of materials, including steel, the invention is particularly well suited for use on aluminum cases that are more prone to damage during removal of the abradable material by conventional methods. - As represented in FIGS. 1 through 5, the
apparatus 10 is able to remove the abradable material while thefan containment case 14 remains mounted to the engine. Theapparatus 10 is shown as comprising aframe assembly 20 having a base 22,platform 24 andlegs 26 pivotably connected to both thebase 22 andplatform 24. Avertical actuator 28 is mounted to thebase 22 and connected to theplatform 24 to raise and lower theplatform 24 relative to thebase 22. Thebase 22 is shown as being equipped withwheels 29 that enable theapparatus 10 to be moved and positioned in front of thefan section 12. Thewheels 29 are preferably equipped with wheel locks (not shown) of any conventional design to prevent movement of theapparatus 10 once positioned. - A
shaft assembly 30 is rotatably mounted to theplatform 24 in any suitable manner. Anelectric motor 34 andreduction gear assembly 36 is mounted to theplatform 24 for rotating theshaft assembly 30 at an adjustable controlled speed, such as about one rotation per hour, though faster and slower speeds are foreseeable. Aradial arm 38 is mounted to the end of theshaft assembly 30 opposite themotor 34, and extends in a radial direction relative to the axis of rotation of theshaft assembly 30. At the distal end of theradial arm 38, ablast head 40 is mounted by a pair of articulatingarms 42 whose movement and position, and therefore the radial position of theblast head 40, are controlled with aradial adjustor 44 mounted to thearm 38. As will be discussed in greater detail with respect to FIG. 6, theblast head 40 delivers an erosion media (not shown) for the purpose of removing the abradable material from thefan containment case 14. Finally, the orientation (tilt) of theblast head 40 is adjusted with atilt adjustor 46, also mounted to the articulatingarms 42. With theelectric motor 34, the entire assembly—comprising theshaft assembly 30,radial arm 38,arms 42 andblast head 40, etc.—can be caused to rotate about the axis of theshaft assembly 30, which is oriented horizontally in view of the orientation of theengine fan section 12. In this manner, theblast head 40 can be caused to follow the inner circumference of thefan case 14 while spraying the erosion media in a generally radial direction, such that the erosion media impacts the abradable material located on the interior surface of thefan containment case 14, as represented in FIG. 1. - Also shown in FIGS. 1 through 5 is a
chuck assembly 48 mounted to ahousing 32 that supports theshaft assembly 30. Thechuck assembly 48 is shown as comprising three two-bar arm assemblies 50, which as shown in FIG. 1 are adapted to engage thefan containment case 14 and center theshaft assembly 30 with the centerline of thefan section 12. For this purpose, three equiangularly-spacedarm assemblies 50 are preferred, though it is foreseeable that a different number of arms could be used. Thearm assemblies 50 are articulated in unison throughrods 52 connected to acollar 54 mounted with bearings to theshaft assembly 30. As such, thechuck assembly 48 has a horizontal central axis that substantially coincides with the axis of rotation of theshaft assembly 30. Anactuator 56 is coupled to thecollar 54 to move thecollar 54 axially along a given length of theshaft assembly 30, causing thearm assemblies 50 to pivot in unison toward or away from the axis of rotation of theshaft assembly 30. Thedistal end 58 of eacharm assembly 50 is adapted to engage the interior surface of thefan containment case 14, and is equipped with aclamp 60 for gripping thecase 14 with thedistal end 58. - In FIGS. 1 and 2, an
actuator 62 is shown with which theshaft assembly 30—and therefore simultaneously theblast head 40 and chuckassembly 48—can be moved axially, i.e., parallel to the axis of rotation of theshaft assembly 30. Consequently, theblast head 40 can be introduced into thefan section 12, positioned in the cross-sectional plane of thecase 14 containing the abradable material to perform the removal operation, and later retracted from thefan section 12 at the completion of the operation. Simultaneously with the introduction of theblast head 40 in thefan section 12, thearm assemblies 50 are moved toward thefan section 12. Once theblast head 40 is properly axially positioned within thefan section 12, thearm assemblies 50 can be pivoted radially outward with theactuator 56 to engage the rim of thefan containment case 14 and thereby center theshaft assembly 30 within thefan section 12. Finally, finer adjustments can be made to place theblast head 40 immediately adjacent the abradable material through theradial adjustor 44 and thetilt adjustor 46. - The
blast head 40 represented in FIGS. 1 through 5 is shown in greater detail in FIG. 6. Theblast head 40 can be seen to comprise acontainment enclosure 64 for containing the erosion media sprayed through aspray head 66 disposed in a wall of theenclosure 64. Theouter surface 68 of thecontainment enclosure 64 is contoured to correspond to the radius of thefan containment case 14, and is equipped with a rubber or brush seal (not shown) to provide a sealing action with the interior surface of thefan containment case 14. The erosion media is delivered to thespray head 66 through asupply hose 70, and retrieved from theenclosure 64 through a pair ofhoses 72 attached to opposite sides of theenclosure 64. As such, the erosion media is retrieved from thecontainment enclosure 64 after the erosion media is sprayed from thespray head 66 and has impacted the abradable material on the interior surface of thefan containment case 14. Thereafter, the spent erosion media containing particles of the abradable material may be discarded, though in a preferred embodiment the erosion media is separated from particles of the abradable material and reused. - While spray heads66 of various designs may be used, a
preferred spray head 66 is equipped with multiple nozzles, preferably three as shown, that rotate together about the axis along which the media is sprayed. Ablast head 40 equipped with thepreferred spray head 66 and media retrieval and reclamation system particularly suitable for use with this invention is the MPC Series of machines available from Abrasive Blast Systems, Inc., of Abilene, Kans. An erosion material found to be suitable for use with theapparatus 10 of this invention is a plastic bead material formed of Type II urea formaldehyde thermoset per Mil-P-85291, and therefore commercially available from a number of sources. In practice, a suitable particle size for the Mil-P-85291 media is about twenty to about thirty mesh, though smaller and larger particle sizes could be used. When using this plastic erosion media within the stated particle size range, suitable operating parameters for theblast head 40 include an adjustable supply pressure of about 50 to about 80 psi (about 3.5 to about 5.5 bar), such as about 65 psi (about 4.5 bar). The volumetric airflow rate from theenclosure 64 is preferably slightly higher than the flowrate to theenclosure 64 to promote a vacuuming effect for reclaiming the media from theenclosure 64. With these parameters, abradable material has essentially been completely removed from a fan containment casing with a single complete rotation of theblast assembly 40. Some overlap (e.g., about 370 degrees rotation) is generally desirable to ensure that the entire circumference of thecase 14 has been thoroughly treated during the operation. - In the preferred embodiment, the
apparatus 10 is capable of being operated within minimal supervision by an operator. For this purpose, theapparatus 10 is preferably equipped with controls that cause theshaft assembly 30 to rotate and theblast head 40 to spray the media according to predetermined settings. Automatic safety stops are preferably provided to stop the operation of theblast head 40 if theshaft assembly 30 stops rotating. In FIG. 2, acontrol unit 74 is seen mounted to theplatform 24 by which the rotational speed of the blast head 40 (through the shaft assembly 30) is controlled. Connected to thisunit 74 is apendant control 76 with switches, etc., for controlling the operation of thechuck assembly 48 andactuators - In view of the above, the
apparatus 10 of this invention can be used to remove abradable material from an interior surface of afan containment case 14 while thecase 14 remains mounted to a high bypass turbofan engine. Prior to the operation, the fan blades are removed from the engine, theplatform 24 is raised with thevertical actuator 28 to align the axis of the shaft assembly 30 (and therefore the axis of the chuck assembly 48) with the centerline of thefan section 12. Theblast head 40 andarm assemblies 50 can then be introduced into thecase 14 by extending theactuator 62. As a result of actuating theactuator 56 to engage thearm assemblies 50 with the rim of thefan containment case 14, the axis of rotation of theshaft assembly 30 is accurately centered with the centerline of thefan containment case 14. Theblast head 40 can then be moved in the radial direction with thearms 42 andadjustor 44 until thecontainment enclosure 64 contacts the interior surface of thecase 14 and thespray head 66 is positioned over the abradable material. Thereafter, the spraying operation is commenced, with theblast head 40 closely following the entire inner circumferential surface of thecase 14 covered by the abradable material as a result of the operation of themotor 34, controlled with thecontrol unit 74 to rotate theblast head 40 at a predetermined speed. Thecontrol unit 74 can also be employed to terminate the flow of erosion media to and from theblast head 40. - While the invention has been described in terms of a preferred embodiment, it is apparent that other forms could be adopted by one skilled in the art. For example, the physical configuration of the
apparatus 10 could differ from that shown. Therefore, the scope of the invention is to be limited only by the following claims.
Claims (26)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US10/064,896 US6699109B1 (en) | 2002-08-27 | 2002-08-27 | Apparatus and method of removing abradable material from a turbomachine fan containment case |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US10/064,896 US6699109B1 (en) | 2002-08-27 | 2002-08-27 | Apparatus and method of removing abradable material from a turbomachine fan containment case |
Publications (2)
Publication Number | Publication Date |
---|---|
US6699109B1 US6699109B1 (en) | 2004-03-02 |
US20040043703A1 true US20040043703A1 (en) | 2004-03-04 |
Family
ID=31713852
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US10/064,896 Expired - Fee Related US6699109B1 (en) | 2002-08-27 | 2002-08-27 | Apparatus and method of removing abradable material from a turbomachine fan containment case |
Country Status (1)
Country | Link |
---|---|
US (1) | US6699109B1 (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP2497601A1 (en) * | 2011-03-07 | 2012-09-12 | Foure Lagadec | System for treating an inner surface of a conduit by spraying particles |
CN108326702A (en) * | 2018-02-07 | 2018-07-27 | 欧阳克军 | A kind of novel Multifunctional integrated punching grinding machine |
US10443617B2 (en) | 2012-07-02 | 2019-10-15 | United Technologies Corporation | Functionally graded composite fan containment case |
Families Citing this family (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7862587B2 (en) | 2004-02-27 | 2011-01-04 | Jackson Roger P | Dynamic stabilization assemblies, tool set and method |
US7160300B2 (en) | 2004-02-27 | 2007-01-09 | Jackson Roger P | Orthopedic implant rod reduction tool set and method |
US20080152853A1 (en) * | 2006-12-21 | 2008-06-26 | Lee Alan Blanton | Composite containment casings for turbine engine and methods for fabricating the same |
US8016543B2 (en) * | 2007-04-02 | 2011-09-13 | Michael Scott Braley | Composite case armor for jet engine fan case containment |
US8257147B2 (en) * | 2008-03-10 | 2012-09-04 | Regency Technologies, Llc | Method and apparatus for jet-assisted drilling or cutting |
US20100030365A1 (en) * | 2008-07-30 | 2010-02-04 | Pratt & Whitney | Combined matching and inspection process in machining of fan case rub strips |
US8613641B2 (en) * | 2008-10-22 | 2013-12-24 | Pratt & Whitney Canada Corp. | Channel inlet edge deburring for gas diffuser cases |
FR3007063B1 (en) | 2013-06-13 | 2015-07-03 | Composite Ind | ABRADABLE MATERIAL PART FOR MANUFACTURING ABRADABLE ANNULAR JOINT SECTOR FOR TURBOMACHINE AND METHOD OF MANUFACTURING SUCH PART |
FR3007064B1 (en) * | 2013-06-13 | 2018-06-29 | Composite Industrie | ABRADABLE ANNULAR JOINT SECTOR FOR TURBOMACHINE AND METHOD OF MANUFACTURING SUCH A PART |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DK171266B1 (en) * | 1994-02-07 | 1996-08-19 | Toftejorg As | Apparatus for cleaning tank space. |
US5540172A (en) * | 1995-03-16 | 1996-07-30 | Mmc Compliance Engineering, Inc. | Apparatus for performing external surface work on underside of ship hull |
DE19808691A1 (en) * | 1998-03-03 | 1999-09-09 | Tkd Gmbh & Co Kg | Aerial work platform and method for operating an aerial work platform |
-
2002
- 2002-08-27 US US10/064,896 patent/US6699109B1/en not_active Expired - Fee Related
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP2497601A1 (en) * | 2011-03-07 | 2012-09-12 | Foure Lagadec | System for treating an inner surface of a conduit by spraying particles |
US10443617B2 (en) | 2012-07-02 | 2019-10-15 | United Technologies Corporation | Functionally graded composite fan containment case |
CN108326702A (en) * | 2018-02-07 | 2018-07-27 | 欧阳克军 | A kind of novel Multifunctional integrated punching grinding machine |
Also Published As
Publication number | Publication date |
---|---|
US6699109B1 (en) | 2004-03-02 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US6699109B1 (en) | Apparatus and method of removing abradable material from a turbomachine fan containment case | |
US6520838B1 (en) | Shielded spin polishing | |
KR100847165B1 (en) | Apparatus and methods for repairing compressor airfoils in situ | |
US5998755A (en) | Tooling assembly for positioning airfoils of a rotary machine | |
US10493589B2 (en) | Apparatus for shortening the rotor blades of a turbomachine | |
US6183347B1 (en) | Sustained surface step scrubbing | |
US8506361B2 (en) | Fixture to facilitate sandblasting of a cylindrical object | |
TWI655994B (en) | Method and device for setting a predetermined radial gap width for rotor blades of a turbomachine | |
EP2149424B1 (en) | Combined machining and inspection process in machining of fan case rub strips | |
JPH11254324A (en) | Abrasive method and device | |
WO1998007548A1 (en) | Robotic co2 tire mold cleaning | |
CN1822920A (en) | Device and method for polishing large parts | |
EP1058586A1 (en) | Robotic laser tire mold cleaning system and method of use | |
JP2008111433A (en) | Tool for machining rub strip and method for machining rub strip | |
JPH07195364A (en) | Method and device for treating vulcanized rubber surface before bonding | |
US7140216B2 (en) | laser aligned shotpeen nozzle | |
WO1995009714A1 (en) | Robotic polishing of planar and non-planar surfaces | |
CA2368291A1 (en) | Bilayer surface scrubbing | |
US6568994B1 (en) | Shifting edge scrubbing | |
CN105171426B (en) | Combined machining equipment for micro parts | |
JP2007001015A (en) | Wood barking apparatus using dry ice blast and wood barking method | |
CN211103475U (en) | A rust cleaning device for metal casting surface treatment | |
CN221248263U (en) | Casting inner cavity polishing device | |
CN117140277A (en) | Grinding method for outer ring of aero-engine high-pressure turbine casing assembly | |
JPH0349870A (en) | Automatic blast device |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: ABRASIVE BLAST SYSTEMS, INC., KANSAS Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:FORD, ROBERT THOMAS;REEL/FRAME:013449/0008 Effective date: 20020927 Owner name: GENERAL ELECTRIC COMPANY, NEW YORK Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:FOX, MICHAEL DEAN;BRUNER, TERRY JOE;REEL/FRAME:013448/0959;SIGNING DATES FROM 20021015 TO 20021017 Owner name: GENERAL ELECTRIC COMPANY, NEW YORK Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:FORD, ROBERT THOMAS, AS PRESIDENT OF ABRASIVE BLAST SYSTEMS;REEL/FRAME:013449/0045 Effective date: 20020927 |
|
FEPP | Fee payment procedure |
Free format text: PAYOR NUMBER ASSIGNED (ORIGINAL EVENT CODE: ASPN); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY |
|
FPAY | Fee payment |
Year of fee payment: 4 |
|
REMI | Maintenance fee reminder mailed | ||
LAPS | Lapse for failure to pay maintenance fees | ||
STCH | Information on status: patent discontinuation |
Free format text: PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362 |
|
FP | Lapsed due to failure to pay maintenance fee |
Effective date: 20120302 |