EP0236337B1 - Deckscheibe für turbinenläufer - Google Patents
Deckscheibe für turbinenläufer Download PDFInfo
- Publication number
- EP0236337B1 EP0236337B1 EP19860901729 EP86901729A EP0236337B1 EP 0236337 B1 EP0236337 B1 EP 0236337B1 EP 19860901729 EP19860901729 EP 19860901729 EP 86901729 A EP86901729 A EP 86901729A EP 0236337 B1 EP0236337 B1 EP 0236337B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- rotor
- ring segment
- spacer
- blades
- slot
- 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.)
- Expired
Links
Images
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
- F01D5/3007—Fixing blades to rotors; Blade roots ; Blade spacers of axial insertion type
- F01D5/3015—Fixing blades to rotors; Blade roots ; Blade spacers of axial insertion type with side plates
Definitions
- This invention relates generally to gas turbine engine rotors and more particularly to the device for retaining the blades of a bladed rotor against axial movement on the rotor, sealing the gaps at the roots of the blades, dampening blade vibration and to the method of assembling the retaining device.
- Turbine rotor assemblies having removable blades have been used in gas turbine engines and turbochargers to reduce cost and increase serviceability over one-piece rotors.
- the ability to replace worn or damaged blades rather than replacing the entire rotor has allowed the engineer to strive for greater efficiency by reducing the gap or space between the tip of the turbine blade and the surrounding shroud.
- thermal variation expansion from heat and retraction from cooling
- start-up and running modes will vary the clearance and efficiency.
- the current rotor assemblies consist of a forged rotor hub which is machined to accept a plurality of individual blades.
- the root portion of the blades are assembled on the hub to prevent centrifugal force from extracting the blade from the hub.
- a seal ring is attached to the hub to prevent the blades from moving axially out of the hub and to prevent the passage of working gases between the hub and the root portion of the blade. By blocking the space between the root portion of the blade and the hub, the seal causes all the working gas to pass through the working portion of the blade and increases the operating efficiency of the engine.
- US-A-3,807,898 discloses a bladed rotor assembly which has a segmented sealing plate, a groove in the blades, a half-round groove in the plate segments, and a half-round groove which cooperates with the half-round groove in the segments.
- the blades are assembled in the rotor; the segments are inserted in the groove of the blade and a lock wire is circumferentially inserted into the two half-round grooves.
- the seal plate retains the blades in position and seals the flow of working gas from passing between the rotor and the blades.
- the segments overlap one another to prevent leakage past the segments.
- US-A-4,344,740 discloses a rotor assembly which consists of a plurality of attaching slots and lugs on the disk, a plurality of blades equal in number to the slots and a one-piece sideplate has lugs thereon.
- the sideplate is positioned on the rotor with the blades secured in the slots, and the lugs on the rotor and the lugs on the sideplate interleaved.
- the sideplate is forced against the rotor, the lugs are caused to elastically deform and the sideplate is rotated until the lugs on the sideplate are captured beneath the lugs on the rotor.
- An antirotation pin is used to prevent relative movement between the sideplate and the disc.
- US-A-4,523,890 discloses an end seal for a turbine blade base.
- the seal consists of a seal ring and a plurality of seal plate segments.
- the seal ring is positioned between the seal plate segments and the blade at one end, and between the seal plate segments and the turbine wheel at the other end. After installation of the seal ring each of the seal plate segments are conventionally installed.
- US-A-4,523,890 involves increased manufacturing and assembly costs due to the addition of a complex shaped seal ring and a complex machining configuration of the turbine wheel retainer area.
- the above patents describe expensive bladed rotor assembly employing complex machining and assembly techniques. The seal ring must be removed from the rotor to replace a single failed blade and then requires that the complex assembly technique be followed to reassembly.
- a bladed rotor assembly comprising a rotor having opposed faces, a rim and a plurality of circumferentially arrayed retention slots in the rim, the slots passing from one of the faces to the other of the faces and having radial retention means, a plurality of blades mounted on the rotor with each of the blades having a root portion received in a corresponding one of the slots, the root portion being shaped so that it engages the radial retention means to prevent movement of the blade radially outwards of the rotor; means on the rotor and on each of the plurality of blades for defining an annular T-slot at one of the faces; means defining an opening in the means on the rotor which forms a portion of the T-slot; seal means rotatably trapped in the T-slot and including ring segment means having first and second ends circumferentially spaced apart to define therebetween a space wide enough for the passage of a blade root portion, and a spacer
- the invention also includes a method of assembling a bladed rotor assembly, the rotor assembly including a rotor having opposed faces, a rim and a plurality of circumferentially arrayed retention slots in the rim, the slots passing from one of the faces to the other of the faces and having radial retention means; and a plurality of blades mounted on the rotor with each of the blades having a root portion received in a corresponding one of the slots, the root portion being shaped so that it engages the radial retention means to prevent movement of the blade radially outward of the rotor; means on the rotor for forming a circumferentially extending, radially outwardly facing groove on the rotor; and means on each of the plurality of blades for forming a circumferentially extending inwardly facing groove; the method comprising the steps of:
- the present invention provides a simple and inexpensive method of replacing individual worn or damaged blades of a rotor assembly.
- the means for preventing rotation are removed and the seal means which is rotatably trapped in the T-slot is indexed so that the ends of the ring segment means align with the opening in the rotor and the spacer is removed.
- the ring segment means is rotated until the ends align with the worn or damaged blades to be removed and replaced.
- the seal means is indexed to a position at which the spacer is out of alignment with the opening in the rotor, and the means for preventing rotation is secured to the rotor.
- the present invention provides for a simple and inexpensive means to attach a plurality of blades to a rotor while providing a seal to ensure the flow of working gases through the working portion of the turbine blades and for dampening blade vibration.
- the assembly technique is simple and easy to employ. The use of heavy presses for assembly or disassembly and complex machining configuration have been eliminated.
- the present invention is simple to employ, allows for the flexibility of replacing a single or a plurality of worn or damaged blades and does not require a complexity of machining or assembly fixtures.
- a bladed rotor assembly 10 is shown in a gas turbine engine 12.
- the rotor assembly 10 comprises a rotor 14, a plurality of blades 16, means 18 on the rotor and on each of the plurality of blades for defining an annular T-slot 20, means 22 defining an opening 23 in the rotor 14 to provide access to a portion of the T-slot 20, means 24 for sealing positioned in the T-slot 20 and means 26 for preventing relative rotation between the means 24 for sealing and the rotor 14.
- the rotor 14 as shown in Figures 2 and 3, has a center hub 28 and a rim 30 at its perimeter.
- a web 32 connects the hub 28 to the rim 30.
- the rotor 14 has opposite first and second faces 34, 36, of which the first face 34 is stepped or multilevel, a plurality of blind holes 38 in the first face 34 and a plurality of circumferentially arrayed retention slots 40 positioned in the rim 30.
- the slots 40 extend from one face 34 to the other face 36 and have a radial retention means 42 which includes a pair of side walls 43 which are undercut in a conventional manner to provide at least one inwardly directed abutment face 44 on each side wall.
- the plurality of blades 16 are mounted on the rotor 14.
- Each of the plurality of blades has a root section 46 which engages a corresponding slot 40 and is spaced away from a bottom 50 of the slot 40 in the rotor 14.
- the root portion 46 is shaped so that it engages the abutment face 44 of the rotor 14.
- Each blade 16 has a platform section 52 disposed radially outwardly from the periphery of the rim 30 by an extended neck region 54 of the blade 16.
- Each blade has a lip 56 projecting radially inward from the root section 46 and abuts a portion of the multilevel surface of the first face 34.
- the means 18 on the rotor 14 for defining a portion of the T-slot 20 includes a circumferentially extending radially outwardly facing groove 62 which extends axially outward from the first face 34 of the rotor 14.
- the means 18 on each blade 16 for defining a portion of the T-slot 20 includes a circumferentially extending radially inwardly facing groove 64 formed on each blade 16 intermediate the root section 46 and the platform section 52 and on the same side as the lip 56.
- the opening 23 in said means 18 on the rotor 14 which forms a portion of the T-slot 20 opens into the groove 62 and has an arcuate length D 2 for purposes to be defined later.
- the means 24 for sealing includes a ring segment means 74 having first and second ends 76, 78 circumferentially spaced apart to define a space 80 therebetween, and a segment shaped spacer 82 positioned in the space 80.
- the spacer 82 has a circumferential length slightly less than the circumferential length of the space to define a controlled gap 84 or clearance between the spacer 82 and on both of the ends 76, 78 for a later defined purpose.
- the arcuate length D2of the opening 23 is at least equal to the length of the spacer 82.
- the ring segment means 74 is a single ring segment 86 with the ends 76, 78 being the ends thereof.
- the ring segment means 74 and the spacer 82 each have an inner edge 88 and an outer edge 90.
- the inner edges 88 are received in the outwardly facing groove 62 of the rotor 14 and the outer edges 90 are received in the inwardly facing groove 64 of each blade 16.
- the inner edge 88 of the ring segment means 74 has an inner leg portion 92 which is angled away from the first face 34 on the rotor 14 and the outer edge 90 has an outer leg portion 94 which angles away from the root portion 46 of the blade 16.
- the means 26 for preventing relative rotation between the means for sealing 24 and the rotor 14 as shown in Fig.
- the pin 100 includes a hole 100 extending through one of the spacers 82 and ring segment means (74), one of the blind holes 38 in the first face of the rotor 14, and a pin 102 having a diameter slightly smaller than the holes 100, 38.
- the pin 102 has a hollow recess in one end.
- the pin 100 could be a rivet or a bolt inserted through the holes 100 in the spacer 82 and the blind holes would be through drilled in rotor 14.
- the bladed rotor assembly 10 is preassembled prior to assembly into a gas turbine engine 12.
- the single ring segment 86 is assembled into the groove 62 by spreading the ends 76, 78 of the single ring segment 86 over the rotor and releasing the ends with the single ring segment 86 positioned in the groove 62.
- one end of the single ring segment 86 could be inserted through the opening 23 in the rotor 14 and threaded around the groove 62 so that the inner leg portion 88 of the segment 76 is trapped within the groove 62 in the rotor 14.
- the space 80 between the first and second ends 76, 78 of the segment 86 is aligned with one of the slots 40 in the rim 30 of the rotor 14 so that the root portion 46 of the blade 16 will pass therethrough.
- the root portion 46 of one of the plurality of turbine blades 16 is inserted into that slot 40 from the first face 34 side until the lip 56 contacts the first face 34.
- the groove 64 is radially aligned with the groove 62 to form a short portion of the T-slot 20.
- the segment 86 is indexed to align the space 80 with another of the slots 40 in the rotor 14.
- a portion of the segment 86 enters the short portion of the T-slot and locks the blade to the rotor in an axial direction.
- the root portion 46 of a second blade 16 is then inserted into the slot 40 aligned with the space 80 and the segment 86 is again indexed to lock the second blade to the rotor 14 and the space 80 is aligned with the next adjacent slot.
- the sequence of inserting a blade 16 in the slot 40 and indexing the segment 86 is repeated until all the slots 40 contain a blade 16.
- the single ring segment 86 is then rotated to align the space 80 with the opening 23 in the rotor 14.
- the leg portion 94 of the outer edge 90 of the spacer 82 is positioned in the inwardly facing groove 64 formed by the blades 16.
- the segment 86 and spacer 82 are rotated within the T-slot 20 until the hole 100 in the spacer 82 aligns with one of the blind holes 38 in the rotor 14 at which position the spacer 82 is out of alignment with the opening 23 in the rotor 14 and the gap 84 is positioned so that the space between the rotor 14 and the bottom 50 of the blade 16 do not coincide.
- the pin 102 is inserted through the hole 100 in the spacer 82 into the blind hole 38 in the rotor 14 with the hollow end toward the rotor and fixedly attached to the rotor 14 using a punch and a hammer.
- the hollow end is expanded in the hole 38 by tapping the punch againstthe pin 102 with the hammer.
- the bladed rotor assembly 10 will be assembled by a conventional manner into a gas turbine engine 12.
- heat is absorbed in the thin spacer 82 and the single ring segment 86 at a high rate wherein the mass of the rotor absorbs heat at a slower rate. Therefore, the controlled gap 84 between the single ring segment 86 and the spacer 82 will be filled due to the difference in the rate of heat absorbed in the masses in the start up mode. As the engine continues to warm up and enters the steady state mode, the controlled gap 84 will reoccur.
- the primary advantage of the bladed rotor assembly 10 of this invention is in the unique construction of the ring segment means 74 and the spacer 82, and the simple assembly technique which can be used to make a new rotor or repair a damaged rotor. For example, when the bladed rotor assembly 10 has a failed blade 16 and requires that the blade be replaced the rotor assembly 10 will be removed from the engine using conventional disassembly techniques.
- the pin 102 which prevents the means for sealing 24 from rotating relatively to the rotor 14 is removed.
- the ends 76, 78 of the single ring segment 86 are aligned with the opening 23 in the rotor 14 and the spacer 82 is removed from the inwardly facing groove 64 formed by the blades 16.
- the ends 76, 78 of the single ring segment 86 are rotated to align with the damaged blade 16, the blade 16 is removed from the slot 40 in the rotor 14 and a new blade 16 is replaced in the slot 40.
- the single ring segment 86 can be rotated to align with each damaged blade 16 and the blade 16 can be replaced. This process continues until all of the worn or damaged blades 16 are replaced.
- the spacer 82 is repositioned and the pin or pins 102 are secured as discussed earlier.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Turbine Rotor Nozzle Sealing (AREA)
Claims (7)
dadurch gekennzeichnet, dass die Ringsegmentmittel (74) ein einziges Ringsegment (86) aufweisen.
dadurch gekennzeichnet, dass die Ringsegmentmittel (74) ein einziges Ringsegment (86) aufweisen, welches anfangs in der Nut (62) positioniert ist, wobei der Raum (80) durch ein Abstandselement (82) geschlossen ist, welches durch eine Öffnung (23) in die Nut bildende Mittel (18) am Rotor (14) eingeführt wird, wobei der Raum (80) mit der Öffnung (23) ausgerichtet ist, wobei ferner das Abstandselement (82) und die Ringsegmentmittel (74) so weit bewegt werden, bis das Abstandselement (82) in dem T-Schlitz (20) eingefangen ist, und ferner dadurch gekennzeichnet, dass ein Loch (100) sich durch das Abstandselement (82) oder das Ringsegment (86) erstreckt und ausgerichtet ist mit einem Loch (38) in der Stirnfläche (34) des Rotors (14), und wobei ferner Mittel (26) in das Loch eingesetzt sind, um die weitere Bewegung zwischen den Abdichtmitteln (24) und dem Rotor (14) zu verhindern.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US77545185A | 1985-09-12 | 1985-09-12 | |
US775451 | 1985-09-12 |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0236337A1 EP0236337A1 (de) | 1987-09-16 |
EP0236337B1 true EP0236337B1 (de) | 1989-03-01 |
Family
ID=25104469
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP19860901729 Expired EP0236337B1 (de) | 1985-09-12 | 1985-12-06 | Deckscheibe für turbinenläufer |
Country Status (5)
Country | Link |
---|---|
EP (1) | EP0236337B1 (de) |
JP (1) | JPS63500879A (de) |
CA (1) | CA1235071A (de) |
DE (1) | DE3568465D1 (de) |
WO (1) | WO1987001761A1 (de) |
Families Citing this family (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2603333B1 (fr) * | 1986-09-03 | 1990-07-20 | Snecma | Rotor de turbomachine comportant un moyen de verrouillage axial et d'etancheite d'aubes montees dans des brochages axiaux du disque et procede de montage |
US4980774A (en) * | 1988-07-21 | 1990-12-25 | Magnascreen Corporation | Modular flat-screen television displays and modules and circuit drives therefor |
US5079636A (en) * | 1988-07-21 | 1992-01-07 | Magnascreen Corporation | Modular flat-screen television displays and modules and circuit drives therefor |
US5068740A (en) * | 1988-07-21 | 1991-11-26 | Magnascreen Corporation | Modular flat-screen television displays and modules and circuit drives therefor |
US4982272A (en) * | 1988-07-21 | 1991-01-01 | Magnascreen Corporation | Modular flat-screen color television displays and modules and circuit drives therefor |
GB9517369D0 (en) * | 1995-08-24 | 1995-10-25 | Rolls Royce Plc | Bladed rotor |
EP1944471B1 (de) * | 2007-01-09 | 2009-09-02 | Siemens Aktiengesellschaft | Axialer Rotorabschnitt für einen Rotor einer Turbine |
FR2939832B1 (fr) * | 2008-12-11 | 2011-01-07 | Turbomeca | Roue de turbine equipee d'un dispositif de retenue axiale verrouillant des pales par rapport a un disque. |
EP3438410B1 (de) | 2017-08-01 | 2021-09-29 | General Electric Company | Dichtungssystem für eine rotationsmaschine |
FR3127255A1 (fr) * | 2021-09-23 | 2023-03-24 | Safran Aircraft Engines | Ensemble rotatif pour turbomachine |
Family Cites Families (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB905582A (en) * | 1960-05-26 | 1962-09-12 | Rolls Royce | Improvements relating to the sealing of blades in a bladed rotor |
GB954323A (en) * | 1962-03-17 | 1964-04-02 | Rolls Royce | Improvements in or relating to bladed rotors for fluid flow machines such as turbines |
US3300179A (en) * | 1966-04-22 | 1967-01-24 | Gen Motors Corp | Blade stalk cover plate |
GB1095830A (en) * | 1966-09-13 | 1967-12-20 | Rolls Royce | Bladed rotor for a fluid flow machine such as a gas turbine engine |
GB1236920A (en) * | 1967-07-13 | 1971-06-23 | Rolls Royce | Bladed fluid flow machine |
FR2524933B1 (fr) * | 1982-04-13 | 1987-02-20 | Snecma | Dispositif de verrouillage axial d'aubes de rotor de turbine ou de compresseur |
-
1985
- 1985-12-06 EP EP19860901729 patent/EP0236337B1/de not_active Expired
- 1985-12-06 WO PCT/US1985/002402 patent/WO1987001761A1/en active IP Right Grant
- 1985-12-06 DE DE8686901729T patent/DE3568465D1/de not_active Expired
- 1985-12-06 JP JP86502153A patent/JPS63500879A/ja active Pending
-
1986
- 1986-09-09 CA CA000517815A patent/CA1235071A/en not_active Expired
Also Published As
Publication number | Publication date |
---|---|
CA1235071A (en) | 1988-04-12 |
DE3568465D1 (en) | 1989-04-06 |
WO1987001761A1 (en) | 1987-03-26 |
EP0236337A1 (de) | 1987-09-16 |
JPS63500879A (ja) | 1988-03-31 |
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