Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
  • F01D5/00—Blades; Blade-carrying members; Heating, heat-insulating, cooling or antivibration means on the blades or the members
  • F01D5/30—Fixing blades to rotors; Blade roots ; Blade spacers
  • F01D5/32—Locking, e.g. by final locking blades or keys
  • F01D5/326—Locking of axial insertion type blades by other means
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
  • F01D5/00—Blades; Blade-carrying members; Heating, heat-insulating, cooling or antivibration means on the blades or the members
  • F01D5/30—Fixing blades to rotors; Blade roots ; Blade spacers
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
  • F01D5/00—Blades; Blade-carrying members; Heating, heat-insulating, cooling or antivibration means on the blades or the members
  • F01D5/12—Blades
  • F01D5/14—Form or construction
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
  • F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
  • F01D5/00—Blades; Blade-carrying members; Heating, heat-insulating, cooling or antivibration means on the blades or the members
  • F01D5/30—Fixing blades to rotors; Blade roots ; Blade spacers
  • F01D5/32—Locking, e.g. by final locking blades or keys

Definitions

• Turbine wheel equipped with an axial retainer locking blades with respect to a disc.
• the invention relates generally to paddle wheels in gas turbines and more particularly to the axial retention of said blades relative to the axis of the wheel.
• the field of application of the invention is in particular that of industrial gas turbines and aeronautical gas turbine engines.
• a turbine wheel conventionally comprises a plurality of blades, a disk and an axial blade retainer.
• Each blade generally has a blade profile, a platform and a fastener.
• the attachment of each of the blades being engaged in a housing opening at the periphery of the disk and extending axially between two opposite faces of the disk, the housing being separated by teeth.
• the axial blade retainer axially locks the blades relative to the axis of rotation of the disk.
• the invention aims to provide a turbine wheel in which the blades undergo substantially less vibration during operation of the wheel.
• platform of said blade has a projection projecting axially beyond one of the faces of the disc, said projection comprising a second stop member, and the axial projection, the second stop member and said face of the disc form a groove oriented towards the axis of the disc, said groove being intended to receive the axial retaining device, so that the axial retaining device, in mounted position, abuts in the first axial direction against the second stop member and against said face of the disk in a second axial direction opposite to the first axial direction, whereby said blade is locked relative to the disk in the second axial direction.
• the axial retaining device axially locks the blade relative to the disk. Indeed, the blade is blocked axially on the one hand by the first stop member of the disk and on the other hand by the axial retaining device.
• the first stop member blocks the blade axially in the first axial direction
• the axial retainer blocks the blade axially in the second axial direction.
• axial is meant a direction oriented along the axis of the wheel or disk.
• the blade is retained in the housing by shape cooperation between the blade and two teeth of the disk, in a manner known per se.
• the first axial direction is that in which the blades are inserted into the disk housing while the second axial direction is that by which the blades can be removed from the disk.
• the platform of the blade has an axial projection comprising a second stop member.
• the axial projection is provided to extend axially beyond one of the faces of the disk when the blade is mounted on the disk.
• the second stop member is located under the platform and protrudes radially towards the axis of the disc.
• the axial retention device is held in the groove in the first axial direction by the second stop member and in the second axial direction by said face of the disk.
• the axial retention device is also maintained in the radial direction in the centrifugal direction by the bottom of the groove.
• this plating advantageously allows a mechanical coupling between the blade and the axial retention device.
• the relative flexibility of the axial retention device with respect to the rigidity of the blade and the rigidity of the disk allows a damping of the azimuthal component of the vibrations.
• the axial retention of the blades on the disk is correctly ensured and, on the other hand, the vibrations of the blade are damped.
• At least one boss is provided between the axial retaining device and said blade to make a mechanical contact between the blade and the axial retaining device.
• the presence of a boss between the blade and the axial retention device improves the mechanical contact between the blade and the axial retention device, said mechanical contact allowing damping of vibrations of the blade.
• this boss may possibly make it possible to slow down the possible movements of the axial retention device in an azimuthal direction, which improves the safety of the axial retention of the blades.
• the boss is formed on the axial retainer.
• the boss is formed under the axial projection, at the bottom of said groove, that is to say on the face which is facing the axial retaining device.
• a recess of complementary shape to the boss is formed on the element facing the boss, and formed so that the boss comes to lodge in the recess.
• the boss is formed on the axial retention device, the element facing the boss is the platform and the recess is made under the platform. Conversely, if the boss is formed under the platform, the element facing the boss is the axial retention device and the recess is formed at the axial retaining device.
• a recess of complementary shape to the boss makes it possible to further improve the mechanical contact between the blade and the axial retention device by combining the advantages associated with the presence of a simple boss and the advantages related to the presence of facing surfaces without boss. .
• the boss allows permanent contact, and the facing surfaces being very close thanks to the recess of complementary shape to the boss allow additional contact during the rotation of the wheel due to the centrifugal force.
• the boss is housed in a recess, also prevents the rotation of the axial retention device.
• the boss and / or the recess are made on a portion of the platform that does not radially support the blade profile.
• the boss With this arrangement of the boss relative to the blade profile, it is understood that the boss is not located near a radially supporting zone blade profile, the boss is arranged under the platform or on the retainer axial. Thus the mechanical stresses resulting from the interactions between the blade and the axial retention device are applied in an area where the platform is weakly mechanically stressed. Indeed, the areas of the platform close to the blade profile are typically substantially solicited by the blade profile.
• the disk has an anti-rotation cleat capable of blocking the azimuthal movements of the axial retaining device with respect to the disk.
• An anti-rotation cleat makes it possible to ensure that the axial retaining device does not itself rotate during the rotation of Ia. wheel.
• the axial retention device remains correctly positioned.
• this anti-rotation cleat is made in such a way that it guarantees the balance of the wheel.
• the anti-rotation tab balances the mass of the axial retainer which is not necessarily evenly distributed over the entire wheel.
• the assembly composed by the axial retention device and the antirotation cleat has a uniformly distributed mass on the wheel and does not imbalance when the latter rotates.
• the disc also has at least one safety catch able to block the centripetal movements of the axial retention device.
• a safety catch thus arranged makes it possible to block the axial retention device radially in the groove.
• the safety of the axial locking is thus further improved.
• the wheel according to the invention comprises three safety catches uniformly distributed radially every 120 ° angle on the disk.
• the axial retention device is a split annular ring.
• This annular ring has the advantage of being a single member for retaining all the blades on the disc.
• the fact that the ring is split gives it some flexibility vis-à-vis the radial deformations, which is advantageous from the point of view of damping azimuthal vibrations of the blades.
• the ring is advantageously elastic, which allows on the one hand damping of the vibrations of the blades, and on the other hand to facilitate the mounting operation of the latter on the wheel.
• annular ring as axial retention device allows for a simultaneous mechanical coupling of the rod with several blades.
• the ring also achieves a satisfactory damping of the vibrations of each blade which makes it possible to avoid their ruin.
• the ring is prestressed so as to be in contact with a contact pressure with the platform, which ensures the position of the ring relative to the wheel at the stop of the machine.
• the second stop member forms a spoiler and, preferably, the spoiler forms a ring portion extending over at least a portion of the azimuthal length of the axial projection of the blade platform. This preferred form of the second stop member makes it possible to distribute the axial retention forces at the platform of the blade and thus to avoid local peaks of mechanical stresses.
• the present invention also relates to a turbomachine comprising a turbine wheel according to the invention.
• FIG. 1 is an overall view of a turbine wheel according to the invention
• FIG. 2A shows an exploded portion of a turbine wheel of FIG. 1, and FIG. 2B represents the same assembled turbine portion;
• FIG. 3 is a sectional view along plane III of FIG. 2B
• FIG. 4 is a sectional view along plane IV of FIG. 2B
• FIGS. 5A to 5E show different embodiments of the axial retaining ring according to the sectional plane V of FIG. 4, and
• FIG. 6 shows a turbine equipped with a turbine wheel according to the invention.
• FIG. 1 represents an exemplary embodiment of a turbine wheel 10 according to the invention.
• the wheel 10 is composed of a disc 12 having an axis A, a plurality of blades 14 and an axial retaining device 16.
• the axial retaining device 16 is a split annular rod.
• the term “ring” or “split ring” for "axial retention device” will be used.
• Each of the blades 14 has a fastener 140 in the form of a fir tree, a platform 142 and a blade profile 144.
• the fastener 140 is engaged in a housing 120 of the disk 12.
• the housing 120 extend axially between two opposite faces of the disc, and are separated by teeth 121.
• Each blade 14 is retained radially at its attachment 140 by the two adjacent teeth 121 at the clip.
• the disk 12 is equipped with three safety catches 122 arranged at 120 ° angle to each other on the disk. These safety catches 122 hold the rod 16 in its radial position with respect to the disk 12 and the blades 14.
• the disk 12 is also equipped with an anti-rotation cleat 124 to lock the rod 16 in its azimuthal position with respect to the disk 12 and the blades 14.
• the anti-rotation tab 124 is inserted into the slot of the ring 16.
• FIG. 2A shows an angular portion of the wheel 10 of Figure 1 exploded.
• the first stop members 126 and the second stop members 146 are visible.
• the first stop members 126 are housed in cavities 148 of the blades 14.
• the second stop members 146 are arranged on the lower face of the platform 142 on an axial projection of the platform 150 projecting from the face 128 of the disc 12.
• Each second stop member 146 forms a spoiler so that when mounting a blade 14 on the disc 12 from the face 130 of the disc 12, the blade attachment 140 can slide in the housing 120 until the first stop member 126 is housed in a cavity 148
• each spoiler has an additional machining on its azimuth flanges so as not to interfere with the teeth 121 during assembly. Subsequently, the term "spoiler" will be used for "second stop device".
• each spoiler 146 forms a ring portion, so that when the blades 14 are mounted on the disc 12, the set of spurs 146 form a discontinuous ring.
• FIG. 2B represents the wheel portion described in FIG.
• FIG. 3 is a sectional view of the example shown in Figure 2B along the section plane III.
• the blade 14 of FIG. 3 is engaged in its housing 120 in the first axial direction X until one of the contact faces 152 of the platform 142 comes into abutment against the first stop member 126 of the disc 12 The blade is thus blocked in the first axial direction X.
• the rod 16 is disposed under the projection 150, between the face 154 of the blade attachment 140 which is in line with the face 128 of the disc 12, and the face 156 of the spoiler 146 which is opposite the face 154.
• the blade is retained axially in the second axial direction Y opposite the first axial direction X, by the spool 146 which abuts against the ring 16 which itself bears against the face 128 of the disc 12 and the first stop member 126 (see fig.3).
• the blade is retained in the two opposite axial directions X and Y through the interaction of the axial retention device 16, on the one hand with the first stop member 126 and on the other hand with the second stop member 146.
• the platform 142 is provided with at least one boss 170.
• This boss 170 is on the lower face of the platform 142, and more particularly on the lower face of the axial projection 150. More specifically, considering the groove in which the rod 16 is housed, the boss 170 is formed on the bottom of this groove.
• the boss 170 is not disposed directly above the blade profile 144, that is to say that in the axial direction, the blade profile 144 and the boss 170 are staggered. .
• the blade profile 144 is supported radially by the portion of the platform supported by piecing of the blade 140 and does not impinge on the axial projection 150.
• the boss 170 is not located on a part of the platform 142 which radially supports the blade profile 144.
• FIGS. 5A to 5E represent different variants of ring / platform interfaces according to the section plane V of FIG. 4.
• Figure 5 corresponds to the embodiment shown in Figure 4, in the same manner as in Figure 4, a single boss 170 is shown in Figure 5A.
• the ring / platform interface is realized by a contact between the boss 170 and the rod 16.
• the surface 160 of the rod 16 facing the bottom of the groove 158 is substantially smooth.
• FIG. 5B represents an alternative embodiment in which, contrary to the embodiment previously described, the rod 16 has a plurality of bosses 162 positioned along the circumference of the rod (only one boss is shown) while the bottom of the groove 158 is smooth.
• FIGS. 5C and 5D respectively similar to FIGS. 5A and 5B, show bosses 170 and 162 arranged in a recess of complementary shape arranged opposite said boss.
• the bosses 170 are under the platforms 142 while the rod 16 has recesses of complementary shape.
• the bosses 162 are formed on the circumference of the ring 16 while the recesses are formed in the blade platforms 142.
• the ring 16 is then advantageously maintained according to the azimuthal direction by the interaction between the bosses and recesses of complementary shape.
• FIG. 5E is a variant combining the simultaneous presence of bosses and recesses on the rod 16 and on the projection 150.
• FIG. 6 represents a turbomachine 200 equipped with a turbine wheel according to the invention.
• the gas generator turbine wheel 210 and the free turbine wheel 220 are in accordance with the present invention.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Turbine Rotor Nozzle Sealing (AREA)
• Structures Of Non-Positive Displacement Pumps (AREA)

Priority Applications (1)

Applications Claiming Priority (2)

Publications (2)

Family

ID=41056780

Family Applications (1)

Country Status (11)

Cited By (1)

Families Citing this family (15)

Family Cites Families (17)

• 2008
  • 2008-12-11 FR FR0858461A patent/FR2939832B1/fr not_active Expired - Fee Related
• 2009
  • 2009-12-10 PL PL09803826T patent/PL2373872T3/pl unknown
  • 2009-12-10 CN CN200980150190.2A patent/CN102245859B/zh active Active
  • 2009-12-10 JP JP2011540173A patent/JP5726747B2/ja active Active
  • 2009-12-10 RU RU2011128021/06A patent/RU2507400C2/ru not_active IP Right Cessation
  • 2009-12-10 EP EP09803826A patent/EP2373872B1/de active Active
  • 2009-12-10 CA CA2746431A patent/CA2746431C/fr active Active
  • 2009-12-10 US US13/139,109 patent/US8956119B2/en active Active
  • 2009-12-10 ES ES09803826T patent/ES2399851T3/es active Active
  • 2009-12-10 WO PCT/FR2009/052469 patent/WO2010067024A2/fr not_active Ceased
  • 2009-12-10 KR KR1020117015318A patent/KR101672065B1/ko not_active Expired - Fee Related

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events