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EP 3 038 794 B1 |
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EUROPEAN PATENT SPECIFICATION |
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Mention of the grant of the patent: |
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01.01.2020 Bulletin 2020/01 |
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Date of filing: 18.08.2014 |
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International Patent Classification (IPC):
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International application number: |
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PCT/CA2014/000628 |
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International publication number: |
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WO 2015/027310 (05.03.2015 Gazette 2015/09) |
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AIRFOIL MASKING TOOL AND METHOD OF POLISHING AN AIRFOIL
TRAGFLÄCHENMASKIERUNGSWERKZEUG UND VERFAHREN ZUM POLIEREN EINER TRAGFLÄCHE
OUTIL DE MASQUAGE DE PROFIL AÉRODYNAMIQUE ET PROCÉDÉ DE POLISSAGE D'UN PROFIL AÉRODYNAMIQUE
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Designated Contracting States: |
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AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL
NO PL PT RO RS SE SI SK SM TR |
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Priority: |
28.08.2013 US 201361870980 P 21.11.2013 US 201361907207 P 09.12.2013 US 201361913439 P 21.05.2014 US 201461001425 P
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Date of publication of application: |
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06.07.2016 Bulletin 2016/27 |
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Proprietor: MDS Coating Technologies Corp. |
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St Laurent, Quebec H4S 1P4 (CA) |
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Inventors: |
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- MARTIN, Lee
Summerside, Prince Edward Island C1N 6H7 (CA)
- BELL, Joshua
Long River, Prince Edward Island C0B 1M0 (CA)
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Representative: Johansson, Lars E. |
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Hynell Intellectual Property AB
P.O.Box 138 683 23 Hagfors 683 23 Hagfors (SE) |
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References cited: :
EP-A1- 2 617 861 US-A- 3 435 565 US-A- 4 447 992 US-A1- 2004 097 170 US-A1- 2013 323 071 US-B1- 6 261 154 US-B2- 8 105 133
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WO-A1-2013/180944 US-A- 3 482 423 US-A- 4 447 992 US-A1- 2009 282 677 US-B1- 6 261 154 US-B2- 7 066 799 US-B2- 8 308 526
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Note: Within nine months from the publication of the mention of the grant of the European
patent, any person may give notice to the European Patent Office of opposition to
the European patent
granted. Notice of opposition shall be filed in a written reasoned statement. It shall
not be deemed to
have been filed until the opposition fee has been paid. (Art. 99(1) European Patent
Convention).
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Field of the Invention
[0001] The invention relates to an airfoil masking tool as known from patent document
US 2009/282677 A1, which is the basis for the preamble of appended claim 1. The invention also relates
to the use of the masking tool in a method of polishing the airfoil, as known from
patent document
US 2004/097170 A1, which discloses the preamble of appended claim 5 and represents the closest prior-art
to the subject-matter of appended claim 10.
Background of the Invention
[0003] It is widely known that media finishing processes, such as those recipes that are
commonly provided with media finishing equipment sold by the Rosler, Sweco, Giant,
Royson, etc., are able to polish most metal surfaces to achieve surface roughness
Ra measurements in the region of 7 to 25 micro-inches. The media finishing process
typically comprises a tub style, batch bowl, or a continuous flow-through vibratory
finisher filled with hard ceramic media stones of various shapes, abrasive content
and sizes, that is vibrated with an electric motor that spins an eccentric weight.
Hard ceramic media is loaded into the bowl and the act of vibrating the bowl causes
that media to flow in a directional manner and circulate around the bowl. Water and
burnishing compounds are typically added to the bowl to assist in the polishing, and
sometimes a paste or powder may also be added to accelerate the process. The articles
that are to be polished are added to the bowl so that they flow around with the media.
The parts can also be fixed in a stationary position in the bowl, but this is not
typical. An example of a suitable polishing machine is shown in
U.S. Patent No. 6,261,154, which is incorporated herein by reference.
[0004] High energy finishing processes such as high energy tumbling or centrifugal finishing
and drag-finishing are able to achieve lower surface finish conditions. However, the
high energy nature of these processes can result in the loss of material at sharp
edges which may harm the dimensions of the part.
[0005] When it comes to polishing close-toleranced parts such as gas turbine engine airfoils,
the polishing process can be very aggressive on sharp radius edges and corners such
as the leading and trailing edges of the airfoils and blade tip corners. Changes in
the dimensions of the leading and trailing edges and blade tip corners can have a
profoundly detrimental effect on the mechanical properties and aerodynamic efficiency
of the airfoils. Thus, a process for super-polishing close-toleranced airfoils must
be able to preserve the dimensions of these areas and possibly others.
Summary of the Invention
[0006] An objective of the invention is to provide a super-polishing media process that
will avoid altering close-toleranced dimensions of parts such as turbine blades.
[0007] Another objective is to provide an airfoil masking tool constructed to hold and protect
parts of the airfoil during the polishing process.
[0008] The objectives can be obtained by a method of polishing an airfoil as defined in
appended claim 10.
[0009] The objectives can also be obtained by using an airfoil masking tool as defined by
appended claims 1 and 4, as well as an apparatus according to appended claim 5.
Brief Description of the Drawings
[0010]
- Fig. 1
- illustrates a masking tool according to a first embodiment of the invention.
- Fig. 2
- illustrates the airfoil masking tools ganged together in a row.
- Fig. 3
- illustrates a base plate.
- Fig. 4
- illustrates a bladed disc or rotor.
- Figs. 5
- and 6 illustrate a bladed disc or rotor with masking tooling according to a second
embodiment of the invention.
- Fig. 7
- illustrates a graph of the results of an erosion test.
- Fig. 8
- illustrates an erosion test procedure.
- Fig. 9
- illustrates a polishing machine.
- Fig. 10
- illustrates a vane sector with masking tooling according to a third embodiment of
the invention.
Detailed Description of the Invention
[0011] The invention will now be explained with reference to the attached non-limiting figures.
[0012] Fig. 1 illustrates a masking tool 7 designed to hold parts, in this case airfoils
1, during polishing. The tool 7 comprises a body 5 constructed to cover at least the
leading edge 2 or trailing edge 3 or blade tip 4 of the airfoil 1, so that the polishing
media contacts the exposed surface of the airfoil and cannot directly contact the
leading edge 2 or trailing edge 3 or blade tip 4. The airfoil 1 is secured in the
body 5 by means of an end cap 6 to hold the airfoil root and also prevent polishing
in this area. The body 5 and end cap 6 can be made of metal such as but not limited
to steel, titanium, aluminum or nickel alloys or non-metallic materials such as, but
not limited to rubber of varying hardness or plastic such as ABS, Nylon, reinforced
Nylon, polycarbonate, polypropylene, Delran or a combination of the above. The masking
tools 7 can be designed so that there is minimal wear and material loss on the masking
tools 7 so that they can be used multiple times. The airfoil 1 can have a coating
present on the exposed surface. This coating can be applied by physical vapor deposition
methods.
[0013] As shown in Fig. 2, a plurality of airfoil masking tools 8 may be ganged together
in a row 9 and then placed over a plurality of airfoils 10 to be polished. The plurality
of airfoils 10 can be located in one of the slots of a rail 11. The masking tool assembly
fits so that each airfoil leading edge, trailing edge and tip can be automatically
aligned with the associated masking tool 8. Preferably, the exposed surface of the
airfoils to be polished should be aligned so that the flow of polishing medium contacts
the surfaces at the same angle between the medium flow direction and the orientation
of the leading edge/trailing edge chord axis of the airfoils; termed the flow angle.
[0014] The rail of blades 12 or individual masking tools 7 can then be fitted onto a base
plate 13 as shown in Fig. 3. Multiple rails of blades 12 that can be of the same size
and shape, but may also be of different part designs that can be loaded into adjacent
slots on a base plate 13. The fully loaded base plate 13 can then be secured in the
polishing machine, for example a tumbling machine. Equally, the blades may be organized
in other patterns, such as a curve or staggered arrangement, as an alternative to
the linear arrangement shown in Fig. 3. Additionally, the masking tooling may be secured
on a ferromagnetic base plate by means of a magnetic component to hold the tooling
and blade in the correct position without the need for a rail. Additionally, blades
may be mounted into other tooling structures more suited to the type of polishing
machine to be used as exemplified but not limited to tumbling or drag finishing machines.
[0015] Bladed discs or rotors 14, as shown in Fig. 4, are well known engine components that
comprises of airfoils 15 that are integral to the rotor hub. The leading 16 and trailing
edges 17 and blade tips 18 can be protected using masking tooling 19, 20, as shown
in Fig. 5 and as a complete assembly 21 in Fig. 6 in order to prevent excessive material
removal during the tumbling process. The masking tooling can be made from metal such
as but not limited to steel, titanium, aluminum or nickel alloys or non-metallic materials,
such as, but not limited to rubber of varying hardness' or plastic such as ABS, Nylon,
reinforced Nylon, polycarbonate, polypropylene, Delran or a combination of the above.
[0016] Vane sectors 27, as shown in Fig 10, are well known engine components that comprise
airfoils 22, an outer shroud 23, and an inner shroud 24 into which the airfoils are
attached. The leading 25 and trailing 26 edges of the airfoils can be protected by
using a masking tool 30 comprising of two parts; and upper 29 and a lower 28 part;
and as a complete assembly 31 in Fig. 10 in order to prevent excessive material removal
during the polishing process. The masking tooling can be made from metal such as but
not limited to steel, titanium, aluminum or nickel alloys or non-metallic materials,
such as, but not limited to rubber of varying hardness' or plastic such as ABS, Nylon,
reinforced Nylon, polycarbonate, polypropylene, Delran or a combination of the above.
[0017] The present invention can utilize any suitable polishing machine for mass finishing
the surface of workpieces, in particular the airfoil masking tool holding the airfoil.
Fig. 9 illustrates an exemplary embodiment of a suitable polishing machine. The polishing
machine comprises a container or tub 100 which Fig. 9 illustrates as being circular
or toroidal in its shape, and which-in this and related shapes-is referred to as a
"bowl." In its dictionary definition, the term "toroid" refers to "a surface generated
by a plane closed curved rotated about a line that lies in the same plane as the curve
but does not intersect it" (
Merriam-Webster's Collegiate Dictionary, 10th Edition, 1993). The shape is more colloquially referred to as resembling a doughnut. It will be
understood that although a toroid is the best method of describing the shape of this
embodiment of the bowl 100, that the invention is not limited to this particular shape
nor should the term "toroid" as used herein, be limited to structures that meet the
rigorous mathematical definition. Those familiar with solid geometry and the like
will of course recognize that the functional equivalent of a toroid could be made
using slightly different shapes, but that these would fall within the claims of the
invention. Other container shapes that can be used with the present invention include,
but are not limited to, troughs, ovals, and racetrack shapes.
[0018] The tub 100 holds a finishing media which is generally designated by the dotted portions
112. The finishing media is a collection of small objects, usually selected to be
uniform in shape, size, and composition, which strike a workpiece to be finished and
carry out a polishing or abrading action upon it. The nature and type of finishing
media selected for use with the invention is not critical to the invention, but exemplary
media include natural stone, sand, porcelain, ceramic particles of various shapes
and sizes, metal balls, certain natural organic media (e.g. walnut shells), or polymer-based
materials or hybrid multi-component media (e.g. plastic or porcelain with embedded
abrasive particles such as diamond). The individual pieces of the media are also referred
to as "working bodies" to differentiate them from the workpieces being finished. In
Fig. 9, the workpiece 113 to be polished is illustrated as the open wheel 113. It
will be understood that although a simple open wheel is illustrated, the invention
offers significant advantages for workpieces of much more complex shape, as shown
by the airfoil in the attached Figs., and that the simple illustration of Fig. 9 is
included for schematic and illustrative purposes rather than as any limitation of
the claimed invention.
[0019] The invention further comprises means for moving the media 112 in the tub 100 in
a generally revolving motion that is indicated by the arrow 114 in Fig. 9. The control
of the media 112 in the tub 100 is generally well understood in this art and will
not be discussed in detail herein. Exemplary discussions of the manner in which the
motion of the tub 100 can be used to move the media 112 are set forth, for example,
in
U.S. Pat. No. 3,464,674 at Column 3, line 26 though Column 4, line 38, and
U.S. Pat. No. 4,428,161. For example, a motor can be flexibly mounted to the tub and an eccentrically-mounted
weight on a motor shaft can be used for vibrating the motor and the tub when vibrations
are desired.
[0020] One embodiment of the invention is shown in Fig. 9, which utilizes a positioning
and rotating device, examples shown as the rotating shaft or spindle 121, for positioning
and rotating the workpiece 113 that is to be polished in the media 112. The shaft
121 may rotate or hold the workpiece 113 stationary about an axis 124 that is oblique
to the axis 122 about which the media revolves, and does so without moving the position
of the workpiece 113 with respect to the tub 100 as the workpiece 113 is held or rotated.
The workpiece 113 can be made to hold stationary or rotate the workpiece at any angle
to the axis 124 to produce the best desired orientation for polishing the workpiece
113. Instead of using the positioning and rotating device, the workpiece can be mounted
in a fixed position inside the tub 100.
[0021] In addition to the two non-limiting examples of polishing machines disclosed herein,
other polishing machines can be used. The invention is applicable to any polishing
machine capable of adjusting the angle of the flow of the polishing media in relation
to the workpiece being polished. By specifically aligning the airfoils and protecting
the leading edge, trailing edge and tip, the exposed surfaces of the airfoils can
be polished to higher degree. Preferred polishing machines are a tumbling machine,
a high energy centrifugal barrel finishing machine or a drag finishing machine. A
preferred medium is ceramic. The polishing machine should be constructed to flow the
medium with or without an abrasive paste at desired flow angles against the exposed
surfaces of the airfoils. Preferably, the flow angle is selected to provide a surface
roughness Ra of less than 5 micro-inches. Examples of suitable flow angles are 50
to 0 degrees, more preferably 40 to 10 degrees, and most preferably 20 to 10 degrees,
to the orientation of the leading edge/trailing edge chord axis of the airfoils.
[0022] In tumbling machines having two side vibration motors, one can be set at 0 to 50
degrees, and more preferably +10 to 40 degrees, and more preferably +10 to 20 degrees
and the other side motor at 0 to -50 degrees, and more preferably -10 to -40 degrees,
and more preferably -10 to -20 degrees. However the motor orientation can be altered
to change the flow angle of media as necessary such that the flow angle is within
50 to 0 degrees and more preferably 40 to 10 degrees, more preferably 30 to 10 and
most preferably 20 to 10 degrees at the desired angle to the orientation of the leading
edge/trailing edge chord axis of the airfoils.
[0023] Bladed discs or rotors 14, as shown in Fig. 4, are well known engine components that
comprises of airfoils 15 that are integral to the rotor hub. The leading 16 and trailing
edges 17 and blade tips 18 can be protected using masking tooling 19, 20, as shown
in Fig. 5 and as a complete assembly 21 in Fig. 6 in order to prevent excessive material
removal during the tumbling process. The masking tooling can be made from metal such
as but not limited to steel, titanium, aluminum or nickel alloys or non-metallic materials,
such as, but not limited to rubber of varying hardness' or plastic such as ABS, Nylon,
reinforced Nylon, polycarbonate, polypropylene, Delran or a combination of the above.
[0024] A preferred medium for polishing metallic airfoils comprises ceramic media, such
as the RCP porcelain non-abrasive polishing stones that can be acquired from Rösler
along with a Rösler RPP6279 abrasive paste. However, these media are usually not suitable
for polishing airfoils that are coated with an erosion resistant coating such as BlackGold®.
[0025] Surprisingly, a method that was found to produce a surface finish to levels below
4 µin was a medium comprising diamond paste. The paste used to polish the BlackGold®
coating was comprised of a one-micron diamond powder with a gum that serves to keep
the diamond powder on the surface of the ceramic media and a water soluble oil, commonly
used in metallographic polishing, that assists in the acceleration of the polishing
process.
[0026] Preferably the polishing paste comprises a polishing media and a carrier. The polishing
media can be any media suitable for polishing an airfoil. Examples of suitable media
include, but are not limited to, ceramic and diamond. Any suitable carrier for the
media can be used. Preferred carriers comprise gum, water and oil.
[0027] A preferred polishing paste comprises the following components:
at least one gum in the range of 4 to 24 mL, preferably 8 to 16 mL, more preferably
10 to 13 mL;
at least one water soluble oil in the range of 26 to 104 mL, preferably 26 to 78 mL,
and more preferably 45 to 65 mL;
water in the amount of 1 to 3 L; preferably 1 to 2 L and more preferably 1 to 1.6
L;
at least one ceramic media, with the amounts being per 100kg of ceramic media. The
amounts of the components can be adjusted up and down within these ranges for any
desired amount of ceramic media. When polishing a coated airfoil, the polishing paste
preferably further comprises at least one diamond powder in the range of 26 to 156
grams, preferably 52 to 104 grams, and more preferably 65 to 78 grams.
[0028] Examples of suitable polishing paste compositions comprise:
Diamond powder in the range of 100 to 600 grams, preferably 200 to 400 grams and more
preferably 250 to 300 grams;
Gum in the range of 15 to 90 mL, preferably 30 to 60 mL and more preferably 40 to
50 mL;
Water soluble oil in the range of 100 to 400 mL, preferably 100 to 300 mL, and more
preferably 150 to 200 mL;
Water in the range of 3 to 10 L, preferably 4 to 7 L and more preferably 4 to 5 L;
and
Rösler RCP media in the range of 200 to 600 kg, preferably 300 to 500 kg and more
preferably 360 to 410 kg.
[0029] The invention is also suitable for fine adjustments to a structure of the airfoil
or other desired workpiece. For example, the polishing can be conducted to remove
a desired portion of the airfoil to change or alter a dimension or shape of the airfoil.
For example, the airfoil can be machined or cast into a desired shape and then fine
adjustments to the shape can be performed at the same time as polishing, by controlling
the flow of media over the surface of the part such that the action of the media is
more heavily concentrated in the area where a dimensional adjustment is required.
The surface of any desired portion of the airfoil can be removed at the same time
as polishing. This method is suitable for controlled removal of material ranging from
1 micron up to one millimeter in thickness of material from the airfoil.
[0030] The polishing method will be further described with reference to the following non-limiting
examples.
Examples
[0031] The process for the super-finishing of parts such as turbine blades comprises of
the following components:
Example 1
1. Tumbling machine
[0032] The example of the tumbling machine used in this embodiment of the process was a
Walter Trowal MV-25
2. Ceramic media
[0033] The ceramic media used in this process can be almost any media that is suitable for
contacting all areas of the part to be polished. One embodiment of this process used
Rosier RCP porcelain non-abrasive polishing stones to process the parts.
3. An abrasive paste
[0034] The abrasive used in this process comprises :
2.5Kg Rosler paste (RPP6279), or Rosler RPP579, or Walther Trowel SDB Trowapast PKP
5L water
And was a suitable quantity to use with 800-900 lbs Rosier RCP media.
4. Stationary fixed parts
[0035] Airfoils protected with masking tooling similar to that described here were mounted
on a base plate and loaded into the tumbling machine and were held stationary on a
plate in the tumbler as shown in Fig. 3.
[0036] The Walter Trowal MV-25 tumbling machine is equipped with three vibrator motors;
two on the side and one on the base. The two side motors can be oriented individually
about 360 degrees. In the present example, the two side motors were set to 10 degrees
from the horizontal; one at +10 degrees and the other at -10 degrees.
[0037] During operation the three motors were set to 100% power. The media flows in one
direction, for example generally from the leading edge to trailing edge of the airfoils,
and every 14 minutes the medium flow was reversed automatically by the machine so
that the medium flow direction was generally from trailing edge to leading edge and
then from leading edge to trailing edge. This cycle was repeated for 5 to 5½ hours.
Longer or shorter time periods can be used as required to achieve the required surface
finish.
[0038] Once the polishing run was completed the media parts were rinsed with water and a
2-5% by volume of a burnishing compound (brand name Rosier FC120) for 45 minutes to
an hour. At this point the process was complete and the polished parts were removed
from the media. The surface roughness Ra was less than 5 micro-inches.
Example 2
[0039] The same process as Example 1 was used to super polish airfoils that were first coated
with an erosion resistant coating, MDS Coating Technologies' BlackGold® coating. The
erosion resistant coating was applied to the airfoils and once polished according
to the present invention to a surface finish (Ra) of less than 4 µin. The surface
finish retention of the coated and polished surface was compared to an uncoated surface
having a surface finish (Ra) of less than 4 µin by subjecting the polished coated
and uncoated surfaces to erosion using Arizona road dust as the abrasive media. Fig.
7 illustrates the results of the erosion test. The results shown in Fig. 7 demonstrate
that the polished coating prolonged and maintained the surface finish in erosive conditions
to an Ra of less than 10 µin. In contrast, the uncoated polished surface at the same
conditions resulted in a surface finish Ra of 34 µin. The erosion test procedure is
shown schematically in Fig 8.
[0040] The abrasive paste for polishing coated gas turbine blades (Example 1, Item 3) is:
275g of 1 micron diamond powder
45mL xanthan gum
200mL water soluble oil - Anamet Rust Inhibitor
4 - 5 L water
And was a suitable quantity to use with 360 - 410 kg Rosler RCP media.
[0041] While the claimed invention has been described in detail and with reference to specific
embodiments thereof, it will be apparent to one of ordinary skill in the art that
various changes and modifications can be made to the claimed invention without departing
from the scope of the invention as defined by the appended claims.
1. An airfoil masking tool (7,8,21) constructed to hold an airfoil in place during polishing
and further constructed and arranged to cover a root of an airfoil (1,10,15) during
polishing by means of an end cap (6), characterized by a body (5) or bodies (19,20) being constructed and arranged to hold and to cover
a leading edge (2,16), trailing edge (3,17) and tip (4,18) of the airfoil (1,10,15).
2. The airfoil masking tool according to claim 1, further comprising a plurality of masking
tools (8) aligned in a rail (11), or connected together in a row.
3. The airfoil masking tool according to claim 1, further comprising a base plate (13)
to mount the masking tool using a mechanical means, or a magnetic plate or holder
to secure the masking tool on a ferromagnetic base plate.
4. An airfoil masking tool constructed to hold a vane sector with airfoils (22) during
polishing comprising: an upper part (29) and a lower part (28) constructed and arranged
to hold and to cover a leading edge (25) and a trailing edge (26) of the vane sector
(22).
5. An apparatus for finishing the surfaces of an airfoil comprising:
a toroidal tub (100);
finishing media (112) in the toroidal tub (100);
a motor for moving the media in the tub in a generally revolving helical motion in
the tub; characterized by,
an airfoil masking tool according to any of claims 1-4.
6. An apparatus according to claim 5, further comprising a positioning and rotating device
(121) for positioning the body and rotating the body containing an airfoil in the
media about an axis (124) that is oblique to and does not intersect with the axis
(122) about which the media (112) revolves and without moving the position of the
body with respect to the tub (100) as the body rotates, preferably wherein the positioning
and rotating device comprises a rotating shaft, more preferably a plurality of rotating
shafts.
7. An apparatus according to claim 6, wherein the positioning and rotating device being
constructed to change the oblique angle.
8. An apparatus according to claim 5, wherein said media (112) is selected from the group
consisting of: sand, stone, metal, porcelain, natural organic materials, ceramics
and polymeric compositions or hybrid multi-component media, and where preferably said
media further comprises a chemical composition.
9. An apparatus according to claim 5, wherein the shape of the tub (100) is selected
from the group consisting of toroids, bowls, troughs, ovals and racetrack shapes.
10. A method of polishing an airfoil, comprising:
mounting an airfoil (1,10,15; 22) in a masking tool (7,8,21; 28,29) according to any
of claims 1-4, to provide a mounted airfoil (1,10,15; 22);
placing the mounted airfoil (1,10,15; 22) in a polishing machine;
polishing the mounted airfoil (1,10,15) by contacting an exposed surface of the airfoil
(1,10,15,22) with a polishing medium at a flow angle of from 50 to 0 degrees to the
orientation of the leading edge/trailing edge of a chord axis of the airfoil (1,10,15;
22) that provides a surface roughness Ra of less than 5 micro-inches, to form a polished
airfoil having a surface roughness Ra of less than 5 micro-inches, wherein the masking
tool (7,8,21) prevents alterations to the leading edge (2,16), trailing edge (3,17)
and tip (4,18) of the airfoil during polishing or the masking tool (28,29) prevents
alterations to the leading edge (25) and trailing edge (26) of the airfoil (22) during
polishing; and removing the polished airfoil from the masking tool.
11. The method according to claim 10, further comprising mounting a plurality of mounted
airfoils (1,10,15; 22) on a base plate (13) or holder so that exposed surfaces of
the airfoils are aligned and conducting the polishing so that a polishing medium contacts
the exposed surfaces of the airfoils (1,10,15; 22) at a selected flow angle.
12. The method according to claim 10, wherein the flow angle is from 40 to 10 degrees
to the orientation of the leading edge/trailing edge chord axis of the airfoils (1,10,15;
22), preferably 30 to 10 degrees, most preferred 20 to 10 degrees.
13. The method according to claim 10, wherein the airfoil (1,10,15; 22) is coated with
an erosion resistant coating and wherein the polishing media comprises an abrasive
diamond polishing paste.
14. The method according to claim 13, wherein the polishing media comprises:
diamond powder in the range of 26 to 156 grams, more preferably of 52 to 104 grams,
most preferably of 65 to 78 grams;
gum in the range of 4 to 24 mL, more preferably of 8 to 16 mL, most preferably of
10 to 13 mL;
water soluble oil in the range of 26 to 104 mL, more preferably of 26 to 78 mL, most
preferably of 45 to 65 mL; and
water in the range of 1 to 3 L, more preferably of 1 to 2 L, most preferably of 1
to 1.6 L per 100 kg of ceramic media.
15. The method according to claim 10, wherein the polishing process further comprising
making a fine adjustment to a dimension or shape of the airfoil (1,10,15; 22) by a
controlled removal of material in a desired location.
16. The method according to claim 10, further comprising using a positioning and rotating
device to place the mounted airfoil (1,10,15; 22) in the polishing machine and rotating
the mounted airfoil (1,10,15; 22), preferably in the media about an axis (124) that
is oblique to and does not intersect with the axis (122) about which the media (112)
revolves and without moving the position of the body with respect to the tub (100)
as the body rotates.
1. Tragflächenmaskierungswerkzeug (7, 8, 21), konstruiert, um eine Tragfläche während
Polierens in Position zu halten, und weiterhin hergestellt und angeordnet, um eine
Basis einer Tragfläche (1, 10, 15) zu bedecken während Polierens mittels einer Endabdeckung
(6), gekennzeichnet durch einen Körper (5) oder Körper (19, 20), die konstruiert und angeordnet sind, eine
Vorderkante (2, 16), Hinterkante (3, 17) und Spitze (4, 18) der Tragfläche (1, 10,
15) zu halten und zu bedecken.
2. Tragflächenmaskierungswerkzeug gemäß Anspruch 1, weiterhin umfassend eine Mehrzahl
von Maskierungswerkzeugen (8), ausgerichtet in einer Schiene (11) oder miteinander
verbunden in einer Reihe.
3. Tragflächenmaskierungswerkzeug gemäß Anspruch 1, weiterhin umfassend eine Grundplatte
(13), um das Maskierungswerkzeug zu befestigen, verwendend ein mechanisches Mittel
oder eine magnetische Platte oder Halter, um das Maskierungswerkzeug auf einer ferromagnetischen
Grundplatte zu sichern.
4. Tragflächenmaskierungswerkzeug, konstruiert, um einen Leitschaufelsektor mit Tragflächen
(22) während Polierens zu halten, umfassend: einen oberen Teil (29) und einen unteren
Teil (28), konstruiert und angeordnet, um eine Vorderkante (25) und eine Hinterkante
(26) des Leitschaufelsektors (22) zu halten und zu bedecken.
5. Vorrichtung zur Oberflächenbehandlung einer Tragfläche, umfassend:
einen ringförmigen Bottich (100);
Endbearbeitungsmedia (112) in dem ringförmigen Bottich (100);
ein Motor, um die Media in dem Bottich in einer üblicherweise umlaufenden spiralförmigen
Bewegung in dem Bottich zu bewegen; gekennzeichnet durch
ein Tragflächenmaskierungswerkzeug gemäß einem der Ansprüche 1-4.
6. Vorrichtung gemäß Anspruch 5, weiterhin umfassend ein Positionierungs- und Rotationsgerät
(121), um den Körper zu positionieren und den Körper zu rotieren, der eine Tragfläche
in den Media enthält, um eine Achse (124), die schief verläuft zu und nicht schneidet
mit der Achse (122), um welche die Media (112) laufen, und ohne Bewegen der Position
des Körpers in Bezug auf den Bottich (100), wenn sich der Körper dreht, wobei das
Positionierungs- und Rotationsgerät bevorzugt eine Drehwelle, bevorzugter eine Mehrzahl
von Drehwellen umfasst.
7. Vorrichtung gemäß Anspruch 6, wobei das Positionierungs- und Rotationsgerät konstruiert
wird, um den schiefen Winkel zu ändern.
8. Vorrichtung gemäß Anspruch 5, wobei die Media (112) ausgewählt werden aus der Gruppe
bestehend aus: Sand, Stein, Metall, Porzellan, natürliche organische Materialien,
Keramiken und Polymerzusammensetzungen oder hybride Mehrstoffmedien, und wo bevorzugt
die Media weiterhin eine chemische Zusammensetzung umfassen.
9. Vorrichtung gemäß Anspruch 5, wobei die Form des Bottichs (100) ausgewählt wird von
der Gruppe bestehend aus Tori, Schalen, Durchgängen, Ovalen und Rennbahnformen.
10. Verfahren zum Polieren einer Tragfläche, umfassend:
Befestigen einer Tragfläche (1, 10, 15; 22) in einem Maskierungswerkzeug (7, 8, 21;
28, 29) gemäß einem der Ansprüche 1-4, um eine befestigte Tragfläche (1, 10, 15; 22)
bereitzustellen;
Positionieren der befestigten Tragfläche (1, 10, 15; 22) in einer Poliermaschine;
Polieren der befestigten Tragfläche (1, 10, 15) durch Kontaktieren einer exponierten
Oberfläche der Tragfläche (1, 10, 15; 22) mit einem Poliermedium in einem Strömungswinkel
von 50 bis 0 Grad zu der Orientierung von der Vorderkante/Hinterkante einer Profilachse
der Tragfläche (1, 10, 15, 22), die eine Oberflächenrauheit Ra von weniger als 5 Mikrozoll
bereitstellt, um eine polierte Tragfläche zu bilden, aufweisend eine Oberflächenrauheit
Ra von weniger als 5 Mikrozoll, wobei das Maskierungswerkzeug (7, 8, 21) Veränderungen
verhindert an der Vorderkante (2, 16), Hinterkante (3, 17) und Spitze (4, 18) der
Tragfläche während des Polierens oder das Maskierungswerkzeug (28, 29) verhindert
Veränderungen an der Vorderkante (25) und Hinterkante (26) der Tragfläche (22) während
Polierens; und
Entfernen der polierten Tragfläche von dem Maskierungswerkzeug.
11. Verfahren gemäß Anspruch 10, weiterhin umfassend Befestigen einer Mehrzahl von befestigten
Tragflächen (1, 10, 15; 22) auf einer Grundplatte (13) oder Halter, sodass exponierte
Oberflächen der Tragflächen ausgerichtet werden und Durchführen des Polierens, sodass
ein Poliermedium die exponierten Oberflächen der Tragflächen (1, 10, 15; 22) in einem
ausgewählten Strömungswinkel kontaktiert.
12. Verfahren gemäß Anspruch 10, wobei der Strömungswinkel von 40 bis 10 Grad beträgt
zu der Orientierung der Vorderkanten-/Hinterkantenprofilachse der Tragflächen (1,
10, 15; 22), bevorzugt 30 bis 10 Grad, am bevorzugtesten 20 bis 10 Grad.
13. Verfahren gemäß Anspruch 10, wobei die Tragfläche (1, 10, 15; 22) beschichtet ist
mit einer erosionswiderstandsfähigen Beschichtung und wobei die Poliermedia eine abreibende
Diamantpolierpaste umfasst.
14. Verfahren gemäß Anspruch 13, wobei die Poliermedia umfassen:
Diamantpulver im Bereich von 26 bis 156 Gramm, bevorzugter 52 bis 104 Gramm, am bevorzugtesten
65 bis 78 Gramm;
Gummi im Bereich von 4 bis 24mL, mehr bevorzugt 8 bis 16mL, am bevorzugtesten 10 bis
13mL;
wasserlösliches Öl im Bereich von 26 bis 104mL, bevorzugter 26 bis 78mL, am bevorzugtesten
45 bis 65mL; und
Wasser im Bereich von 1 bis 3L, bevorzugter 1 bis 2L, am bevorzugtesten 1 bis 1.6L
pro 100kg Keramikmedia.
15. Verfahren gemäß Anspruch 10, wobei der Polierprozess weiterhin Durchführen einer Feinjustierung
umfasst an einer Abmessung oder Form der Tragfläche (1, 10, 15; 22) durch ein kontrolliertes
Entfernen von Material an einer gewünschten Stelle.
16. Verfahren gemäß Anspruch 10, weiterhin umfassend Verwenden eines Positionierungs-
und Rotationsgeräts, um die befestigte Tragfläche (1, 10, 15; 22) in der Poliermaschine
zu platzieren, und die befestigte Tragfläche (1, 10, 15; 22) zu rotieren, bevorzugt
in den Media um eine Achse (124), die schief verläuft zu und nicht schneidet mit der
Achse (122), um welche das Medium (112) läuft, und ohne Bewegen der Position des Körpers
in Bezug auf den Bottich (100), wenn der Körper rotiert.
1. Un outil de masquage (7, 8, 21) pour profil aérodynamique conçu pour maintenir un
profil aérodynamique en place pendant le polissage et en outre conçu et agencé pour
recouvrir une base d'un profil aérodynamique (1, 10, 15) pendant le polissage au moyen
d'un couvercle d'extrémité (6),
caractérisé par un corps (5) ou des corps (19, 20) qui sont conçus et agencés pour maintenir et recouvrir
un bord d'attaque (2, 16), un bord de fuite (3, 17) et un bout (4, 18) du profil aérodynamique
(1, 10, 15).
2. L'outil de masquage pour profil aérodynamique selon la revendication 1, comprenant
en outre une pluralité d'outils de masquage (8) alignés dans un rail (11), ou reliés
ensemble en une rangée.
3. L'outil de masquage pour profil aérodynamique selon la revendication 1, comprenant
en outre une plaque de base (13) pour monter l'outil de masquage en utilisant un moyen
mécanique, ou une plaque ou un support magnétique pour fixer l'outil de masquage sur
une plaque de base ferromagnétique.
4. Un outil de masquage pour profil aérodynamique conçu pour maintenir un secteur d'ailette
avec des profils aérodynamiques (22) pendant le polissage, comprenant : une partie
supérieure (29) et une partie inférieure (28) conçues et agencées pour maintenir et
recouvrir un bord d'attaque (25) et un bord de fuite (26) du secteur d'ailette (22).
5. Un appareil de finition des surfaces d'un profil aérodynamique comprenant :
une cuve toroïdale (100) ;
un milieu de finition (112) placé dans la cuve toroïdale (100) ;
un moteur pour déplacer le milieu présent dans la cuve selon un mouvement hélicoïdal
généralement rotatif dans la cuve ; caractérisé par
un outil de masquage pour profil aérodynamique selon l'une quelconque des revendications
1 à 4.
6. Un appareil selon la revendication 5, comprenant en outre un dispositif de positionnement
et de rotation (121) pour positionner le corps et faire tourner le corps contenant
un profil aérodynamique dans le milieu autour d'un axe (124) qui est oblique par rapport
à l'axe (122) autour duquel le milieu (112) tourne et n'est pas en intersection avec
celui-ci, sans déplacer la position du corps par rapport à la cuve (100) lorsque le
corps tourne, le dispositif de positionnement et de rotation comprenant de préférence
un arbre rotatif, et de façon encore préférée une pluralité d'arbres rotatifs.
7. Un appareil selon la revendication 6, dans lequel le dispositif de positionnement
et de rotation est conçu pour modifier l'angle oblique.
8. Un appareil selon la revendication 5, dans lequel ledit milieu (112) est choisi dans
le groupe constitué par : le sable, la pierre, le métal, la porcelaine, les matériaux
organiques naturels, les céramiques et les compositions polymères ou les milieux hybrides
à plusieurs composants, et dans lequel de préférence ledit milieu comprend en outre
une composition chimique.
9. Un appareil selon la revendication 5, dans lequel la forme de la cuve (100) est choisie
dans le groupe constitué par des formes toroïdales, en bols, en bacs, en ovale et
en pistes de course.
10. Un procédé de polissage d'un profil aérodynamique, comprenant :
le fait de monter un profil aérodynamique (1, 10, 15 ; 22) dans un outil de masquage
(7, 8, 21 ; 28, 29) selon l'une quelconque des revendications 1 à 4, pour fournir
un profil aérodynamique monté (1, 10, 15 ; 22) ;
le fait de placer le profil aérodynamique monté (1, 10, 15 ; 22) dans une machine
de polissage ;
le fait de polir le profil aérodynamique monté (1, 10, 15) en mettant en contact une
surface exposée du profil aérodynamique (1, 10, 15, 22) avec un milieu de polissage
selon un angle d'écoulement de 50 à 0 degrés par rapport à l'orientation du bord d'attaque
/ bord de fuite d'un axe de corde du profil aérodynamique (1, 10, 15 ; 22) qui fournit
une rugosité de surface Ra inférieure à 5 micro-pouces, pour former un profil aérodynamique
poli ayant une rugosité de surface Ra inférieure à 5 micro-pouces, l'outil de masquage
(7, 8, 21) empêchant des altérations au bord d'attaque (2, 16), au bord de fuite (3,
17) et au bout (4, 18) du profil aérodynamique pendant le polissage ou l'outil de
masquage (28, 29) empêchant des altérations au bord d'attaque (25) et au bord de fuite
(26) du profil aérodynamique (22) pendant le polissage ; et en enlevant le profil
aérodynamique poli de l'outil de masquage.
11. Le procédé selon la revendication 10, comprenant en outre le fait de monter une pluralité
de profils aérodynamiques montés (1, 10, 15 ; 22) sur une plaque de base (13) ou un
support de sorte que les surfaces exposées des profils aérodynamiques soient alignées,
et le fait de conduire le polissage de sorte qu'un milieu de polissage vienne en contact
avec les surfaces exposées des profils aérodynamiques (1, 10, 15 ; 22) selon un angle
d'écoulement sélectionné.
12. Le procédé selon la revendication 10, dans lequel l'angle d'écoulement est de 40 à
10 degrés par rapport à l'orientation de l'axe de corde du bord d'attaque / bord de
fuite des profils aérodynamiques (1, 10, 15 ; 22), de préférence de 30 à 10 degrés,
et de façon la plus préférée de 20 à 10 degrés.
13. Le procédé selon la revendication 10, dans lequel le profil aérodynamique (1, 10,
15 ; 22) est revêtu d'un revêtement résistant à l'érosion et dans lequel le milieu
de polissage comprend une pâte abrasive de polissage au diamant.
14. Le procédé selon la revendication 13, dans lequel le milieu de polissage comprend
:
de la poudre de diamant dans la gamme allant de 26 à 156 grammes, de façon préférée
de 52 à 104 grammes, et de façon la plus préférée de 65 à 78 grammes ;
de la gomme dans la gamme allant de 4 à 24 mL, de préférence de 8 à 16 mL, et de façon
la plus préférée de 10 à 13 mL ;
de l'huile hydrosoluble dans la gamme allant de 26 à 104 mL, de préférence de 26 à
78 mL, et de façon la plus préférée de 45 à 65 mL ; et
de l'eau dans la gamme allant de 1 à 3 L, de préférence de 1 à 2 L, et de façon la
plus préférée de 1 à 1,6 L pour 100 kg de produits céramiques.
15. Le procédé selon la revendication 10, dans lequel le procédé de polissage comprend
en outre le fait de réaliser un ajustement fin à une dimension ou une forme du profil
aérodynamique (1, 10, 15 ; 22) par un enlèvement contrôlé du matériau au niveau d'un
emplacement souhaité.
16. Le procédé selon la revendication 10, comprenant en outre le fait d'utiliser un dispositif
de positionnement et de rotation pour placer le profil aérodynamique monté (1, 10,
15 ; 22) dans la machine de polissage et le fait de faire tourner le profil aérodynamique
monté (1, 10, 15 ; 22), de préférence dans le milieu, autour d'un axe (124) qui est
oblique par rapport à l'axe (122) autour duquel le milieu (112) tourne et qui n'est
pas en intersection avec celui-ci, et sans déplacer la position du corps par rapport
à la cuve (100) lorsque le corps tourne.
REFERENCES CITED IN THE DESCRIPTION
This list of references cited by the applicant is for the reader's convenience only.
It does not form part of the European patent document. Even though great care has
been taken in compiling the references, errors or omissions cannot be excluded and
the EPO disclaims all liability in this regard.
Patent documents cited in the description
Non-patent literature cited in the description
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