EP0707136B1 - Drum rotor for an axial flow turbomachine - Google Patents

Drum rotor for an axial flow turbomachine Download PDF

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Publication number
EP0707136B1
EP0707136B1 EP95810615A EP95810615A EP0707136B1 EP 0707136 B1 EP0707136 B1 EP 0707136B1 EP 95810615 A EP95810615 A EP 95810615A EP 95810615 A EP95810615 A EP 95810615A EP 0707136 B1 EP0707136 B1 EP 0707136B1
Authority
EP
European Patent Office
Prior art keywords
groove
blade
radii
blade groove
drum rotor
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 - Lifetime
Application number
EP95810615A
Other languages
German (de)
French (fr)
Other versions
EP0707136A1 (en
Inventor
Flemming Christensen
Uy-Liem Dr. Nguyen
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
ABB AG Germany
Original Assignee
ABB Asea Brown Boveri Ltd
Asea Brown Boveri AB
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by ABB Asea Brown Boveri Ltd, Asea Brown Boveri AB filed Critical ABB Asea Brown Boveri Ltd
Publication of EP0707136A1 publication Critical patent/EP0707136A1/en
Application granted granted Critical
Publication of EP0707136B1 publication Critical patent/EP0707136B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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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
    • F01D5/3023—Fixing blades to rotors; Blade roots ; Blade spacers of radial insertion type, e.g. in individual recesses
    • F01D5/303—Fixing blades to rotors; Blade roots ; Blade spacers of radial insertion type, e.g. in individual recesses in a circumferential slot
    • F01D5/3038—Fixing blades to rotors; Blade roots ; Blade spacers of radial insertion type, e.g. in individual recesses in a circumferential slot the slot having inwardly directed abutment faces on both sides

Definitions

  • the invention relates to a drum rotor for an axial flowed through turbomachine, in which the blades with their feet in rows in circumferential blade grooves lateral tines are attached.
  • Such drum rotors are known from EP 0 520 260 B1.
  • the rotating ones change Blade grooves have their axial dimension with every rotor revolution. Due to the resulting changing voltages, damage to the rotor turns.
  • damage to the rotor turns.
  • at Temperature changes for example in operational Fluctuations in the first blade groove are strong asymmetrical Shifts occur.
  • To avoid damage usually becomes one before the first blade groove empty, circumferential pre-groove arranged. This pre-groove however, weakens the drum rotor and disrupts the flow of the Work equipment.
  • the lead groove is therefore mostly with Lock segments equipped. The Vornut and the Closure segments create additional work production and assembly, as well as an additional one Material consumption.
  • the invention is based, with one Drum rotor of the type mentioned at the outset and asymmetrical deformations of the first blade groove one calculated using the finite element method Avoid geometrical shaping of the blade groove.
  • the advantages of the invention are among them see that the rotor properties remain unchanged.
  • the Flow of the work equipment is not affected.
  • the Blade groove can be manufactured and without significant additional effort all conventional parts, such as blades, can be used without Adjustments are used.
  • Blade grooves corresponding to the first blade groove be shaped asymmetrically to include in them Axial shifts and asymmetrical deformations too avoid.
  • FIG. 1 shows the first three rows of a high-pressure rotor 1.
  • the individual blades consisting of blade 2 and Blade root 3, are in circumferential blade grooves 10, 11 and 12 used.
  • the blade groove 10 is there on the steam inlet side, the blade groove 12 on the steam outlet side.
  • the flow-limiting contour 4 of the not shown Cylinder is shown in dash-dot lines.
  • Fig. 2 shows the hammer head shape of the blade root 3 in Detail. The forces occurring during operation are over Carrying teeth 5 of the blade groove 10 are introduced into the rotor 1.
  • the previous groove contour 6 is shown in dashed lines on the steam inlet side.
  • the previous groove contour is retained on the steam outlet side.
  • the asymmetrical shape of the blade groove 10 is described by a plurality of successive radii R1, R2, R3 and R4.
  • the radius R1 is larger than R2, R2 is larger than R3 and R3 is larger than R4.
  • Points A, B, C, D and E are defined on the contour of the part of the blade groove 10 which is described by the radii R1 to R4. These points divide the contour on the steam inlet side into circular arcs 21, 22, 23 and 24 described by the radii R1 to R4.
  • Circular arc 21 goes from point A to point B
  • circular arc 22 goes from point B to point C, and so on.
  • the points AE are locations of common tangents of the partial curves touching each other there.
  • a straight line T through the point C is a tangent to the circular arc 22 described by the radius R2
  • the straight line T is also a tangent to the circular arc 23 described by the radius R3.
  • the centers of the circular arcs 22 and 23 are perpendicular to the tangent T through point C. The same applies to the centers of the other arcs.
  • the groove is returned to the previous groove contour by an essentially arbitrarily shaped curve 25 at point F.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Turbine Rotor Nozzle Sealing (AREA)

Description

Technisches GebietTechnical field

Die Erfindung betrifft einen Trommelrotor für eine axial durchströmte Turbomaschine, in welchem die Schaufeln mit ihren Füssen reihenweise in umlaufenden Schaufelnuten mit seitlichen Tragzacken befestigt sind.The invention relates to a drum rotor for an axial flowed through turbomachine, in which the blades with their feet in rows in circumferential blade grooves lateral tines are attached.

Stand der TechnikState of the art

Derartige Trommelrotoren sind bekannt aus EP 0 520 260 B1. Infolge der Rotordurchbiegung verändern die umlaufenden Schaufelnuten bei jeder Rotorumdrehung ihre axiale Dimension. Durch die dabei entstehenden wechselnden Spannungen können an den Rotoreindrehungen Schäden entstehen. Daneben können bei Temperaturänderungen, beispielsweise bei betrieblichen Schwankungen in der ersten Schaufelnut starke asymmetrische Verschiebungen auftreten. Um Beschädigungen zu vermeiden, wird üblicherweise vor der ersten Schaufelnut eine unbestückte, umlaufende Vornut angeordnet. Diese Vornut schwächt jedoch den Trommelrotor und stört den Fluss des Arbeitsmittels. Die Vornut wird deshalb meistens mit Verschlusssegmenten bestückt. Die Vornut und die Verschlusssegmente erzeugen einen Mehraufwand an Arbeit bei der Produktion und der Montage, sowie einen zusätzlichen Materialverbrauch.Such drum rotors are known from EP 0 520 260 B1. As a result of the rotor deflection, the rotating ones change Blade grooves have their axial dimension with every rotor revolution. Due to the resulting changing voltages, damage to the rotor turns. In addition, at Temperature changes, for example in operational Fluctuations in the first blade groove are strong asymmetrical Shifts occur. To avoid damage, usually becomes one before the first blade groove empty, circumferential pre-groove arranged. This pre-groove however, weakens the drum rotor and disrupts the flow of the Work equipment. The lead groove is therefore mostly with Lock segments equipped. The Vornut and the Closure segments create additional work production and assembly, as well as an additional one Material consumption.

Darstellung der ErfindungPresentation of the invention

Der Erfindung liegt die Aufgabe zugrunde, bei einem Trommelrotor der eingangs genannten Art Axialverschiebungen und asymmetrische Deformationen der ersten Schaufelnut durch eine mit Hilfe der Methode der finiten Elemente berechnete geometrische Ausformung der Schaufelnut zu vermeiden.The invention is based, with one Drum rotor of the type mentioned at the outset and asymmetrical deformations of the first blade groove one calculated using the finite element method Avoid geometrical shaping of the blade groove.

Erfindungsgemäss wird dies durch den kennzeichnenden Teil des Patentanspruches erreicht.According to the invention, this is done by the characterizing part of claim reached.

Die Vorteile der Erfindung sind unter anderem darin zu sehen, dass die Rotoreigenschaften unverändert bleiben. Die Strömung des Arbeitsmittels wird nicht beeinflusst. Die Schaufelnut kann ohne wesentlichen Mehraufwand gefertigt und alle herkömmlichen Teile, wie Laufschaufeln können ohne Anpassungen verwendet werden.The advantages of the invention are among them see that the rotor properties remain unchanged. The Flow of the work equipment is not affected. The Blade groove can be manufactured and without significant additional effort all conventional parts, such as blades, can be used without Adjustments are used.

Es ist besonders zweckmässig, wenn die weiteren Schaufelnuten entsprechend der ersten Schaufelnut asymmetrisch ausgeformt werden, um auch in ihnen Axialverschiebungen und asymmetrische Deformationen zu vermeiden. It is particularly useful if the others Blade grooves corresponding to the first blade groove be shaped asymmetrically to include in them Axial shifts and asymmetrical deformations too avoid.

Kurze Beschreibung der ZeichnungBrief description of the drawing

In der Zeichnung ist ein Ausführungsbeispiel der Erfindung anhand einer axial durchströmten Dampfturbine schematisch dargestellt.
Es zeigen:

Fig. 1
einen Teillängsschnitt eines beschaufelten Trommelrotors;
Fig. 2
einen vergrösserten Ausschnitt des Details II aus Fig.1.
In the drawing, an embodiment of the invention is shown schematically using an axially flow-through steam turbine.
Show it:
Fig. 1
a partial longitudinal section of a bladed drum rotor;
Fig. 2
an enlarged section of detail II of Fig.1.

Es sind nur die für das Verständnis der Erfindung wesentlichen Elemente gezeigt. Nicht dargestellt sind von der Anlage beispielsweise sämtliche nichtrotierenden Teile. Die Strömungsrichtung des Arbeitsmittels ist mit einem Pfeil bezeichnet.It is only essential for understanding the invention Elements shown. The system is not shown for example all non-rotating parts. The The direction of flow of the working fluid is with an arrow designated.

Weg zur Ausführung der ErfindungWay of carrying out the invention

Fig. 1 zeigt die ersten drei Laufreihen eines Hochdruckrotors 1. Die einzelnen Schaufeln, bestehend aus Schaufelblatt 2 und Schaufelfuss 3, sind in umlaufenden Schaufelnuten 10, 11 und 12 eingesetzt. Die Schaufelnut 10 liegt dabei dampfeintrittseitig, die Schaufelnut 12 dampfaustrittseitig. Die strömungsbegrenzende Kontur 4 des nicht dargestellten Zylinders ist strichpunktiert angegeben.1 shows the first three rows of a high-pressure rotor 1. The individual blades, consisting of blade 2 and Blade root 3, are in circumferential blade grooves 10, 11 and 12 used. The blade groove 10 is there on the steam inlet side, the blade groove 12 on the steam outlet side. The flow-limiting contour 4 of the not shown Cylinder is shown in dash-dot lines.

Fig. 2 zeigt die Hammerkopfform des Schaufelfusses 3 im Detail. Die beim Betrieb auftretenden Kräfte werden über Tragezacken 5 der Schaufelnut 10 in den Rotor 1 eingeleitet. Fig. 2 shows the hammer head shape of the blade root 3 in Detail. The forces occurring during operation are over Carrying teeth 5 of the blade groove 10 are introduced into the rotor 1.

Dampfeintrittseitig ist die bisherige Nutkontur 6 gestrichelt dargestellt. Dampfaustrittseitig wird die bisherige Nutkontur beibehalten.
Die asymmetrische Form der Schaufelnut 10 wird durch mehrere, aufeinanderfolgende Radien R1, R2, R3 und R4 beschrieben. Der Radius R1 ist grösser als R2, R2 ist grösser als R3 und R3 ist grösser als R4. Auf der Kontur des Teiles der Schaufelnut 10, der durch die Radien R1 bis R4 beschrieben wird, sind Punkte A, B, C, D und E definiert. Diese Punkte unterteilen die dampfeintrittseitige Kontur in durch die Radien R1 bis R4 beschriebene Kreisbögen 21, 22, 23 und 24. Kreisbogen 21 geht dabei von Punkt A zu Punkt B, Kreisbogen 22 geht von Punkt B zu Punkt C, und so weiter. Die Punkte A-E sind jeweils Orte von gemeinsamen Tangenten der sich dort berührenden Teilkurven. So sei eine Gerade T durch den Punkt C eine Tangente des durch den Radius R2 beschriebenen Kreisbogens 22, dann ist die Gerade T auch Tangente des durch den Radius R3 beschriebenen Kreisbogens 23. Daraus folgt, dass die Mittelpunkte der Kreisbögen 22 und 23 auf einer senkrechten zur Tangenten T durch den Punkt C liegen. Entsprechendes gilt für die Mittelpunkte der weiteren Kreisbögen. Vom Punkt E aus wird die Nut durch eine im wesentlichen beliebig geformte Kurve 25 im Punkt F in die bisherige Nutkontur zurückgeführt.The previous groove contour 6 is shown in dashed lines on the steam inlet side. The previous groove contour is retained on the steam outlet side.
The asymmetrical shape of the blade groove 10 is described by a plurality of successive radii R1, R2, R3 and R4. The radius R1 is larger than R2, R2 is larger than R3 and R3 is larger than R4. Points A, B, C, D and E are defined on the contour of the part of the blade groove 10 which is described by the radii R1 to R4. These points divide the contour on the steam inlet side into circular arcs 21, 22, 23 and 24 described by the radii R1 to R4. Circular arc 21 goes from point A to point B, circular arc 22 goes from point B to point C, and so on. The points AE are locations of common tangents of the partial curves touching each other there. Thus, if a straight line T through the point C is a tangent to the circular arc 22 described by the radius R2, then the straight line T is also a tangent to the circular arc 23 described by the radius R3. It follows that the centers of the circular arcs 22 and 23 are perpendicular to the tangent T through point C. The same applies to the centers of the other arcs. From point E, the groove is returned to the previous groove contour by an essentially arbitrarily shaped curve 25 at point F.

Selbstverständlich ist die Erfindung nicht auf das gezeigte und beschriebene Ausführungsbeispiel beschränkt. Die Anzahl und Grösse der zur Beschreibung der asymmetrischen Nut verwendeten Radien muss den jeweiligen Erfordernissen angepasst werden. Of course, the invention is not as shown and described embodiment limited. The number and size of the description of the asymmetrical groove The radii used must meet the respective requirements be adjusted.

BezugszeichenlisteReference list

11
Rotorrotor
22nd
SchaufelblattAirfoil
33rd
SchaufelfussBlade root
44th
ZylinderkonturCylinder contour
55
TragezackenCarrying teeth
66
bisherige Nutkonturprevious groove contour
1010th
erste Schaufelnutfirst blade groove
1111
zweite Schaufelnutsecond blade groove
1212th
dritte Schaufelnutthird blade groove
2121
Kreisbogen A-BCircular arc A-B
2222
Kreisbogen B-CCircular arc B-C
2323
Kreisbogen C-DCircular arc C-D
2424th
Kreisbogen D-ECircular arc D-E
2525th
Teilkurve E-FSub-curve E-F
R1, R2, R3, R4R1, R2, R3, R4
Radien der KreisbögenRadii of the arcs
A-FA-F
Punkte auf der NutkonturPoints on the groove contour

Claims (1)

  1. Drum rotor (1) for an axial-flow turbomachine, in which the blades are fastened with their roots (3) in rows in encircling blade grooves (10, 11, 12) having lateral supporting prongs, characterized in that at least the first blade groove (10) on the inlet side of the working medium is formed in an asymmetrical manner, and in that that contour of the blade groove (10) which is on the inlet side of the working medium is shaped by a plurality of radii (R1-R4), the radii of the successive circular arcs of the row further decreasing as they proceed from the groove base of the blade groove (10), and the circular arcs (21-24) formed by the radii (R1-R4) having a common tangent (T) at their contact points.
EP95810615A 1994-10-14 1995-10-03 Drum rotor for an axial flow turbomachine Expired - Lifetime EP0707136B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE4436727 1994-10-14
DE4436727A DE4436727A1 (en) 1994-10-14 1994-10-14 Drum rotor for an axially flowed turbo machine

Publications (2)

Publication Number Publication Date
EP0707136A1 EP0707136A1 (en) 1996-04-17
EP0707136B1 true EP0707136B1 (en) 1998-11-25

Family

ID=6530754

Family Applications (1)

Application Number Title Priority Date Filing Date
EP95810615A Expired - Lifetime EP0707136B1 (en) 1994-10-14 1995-10-03 Drum rotor for an axial flow turbomachine

Country Status (4)

Country Link
US (1) US5575623A (en)
EP (1) EP0707136B1 (en)
JP (1) JP3665394B2 (en)
DE (2) DE4436727A1 (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20100074754A1 (en) * 2008-09-19 2010-03-25 Thunder Tiger Corporation Securing Device For Connecting Blades To Blade-Root Attachment Of Remote-Control Helicopters
CH702204A1 (en) * 2009-11-10 2011-05-13 Alstom Technology Ltd Rotor for axial flow turbomachine i.e. gas turbine, in combined cycle power plant, has rotating blades inserted into groove, and blade root comprising inverted-T root with hammer head and adapted to base area of groove in radial direction
US8734112B2 (en) 2010-11-30 2014-05-27 United Technologies Corporation Asymmetrical rotor blade slot attachment

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4191509A (en) * 1977-12-27 1980-03-04 United Technologies Corporation Rotor blade attachment
JPS58167807A (en) * 1982-03-29 1983-10-04 Hitachi Ltd Blade installation structure of turbo-machinery
RU1784065C (en) * 1989-05-31 1992-12-23 О.И. Довгаус Turbine disk
US5141401A (en) * 1990-09-27 1992-08-25 General Electric Company Stress-relieved rotor blade attachment slot
EP0520259B1 (en) * 1991-06-28 1994-09-21 Asea Brown Boveri Ag Keying of rotor blades
EP0520260B1 (en) * 1991-06-28 1994-04-13 Asea Brown Boveri Ag Drum rotor for an axial turbine
US5474423A (en) * 1994-10-12 1995-12-12 General Electric Co. Bucket and wheel dovetail design for turbine rotors

Also Published As

Publication number Publication date
EP0707136A1 (en) 1996-04-17
US5575623A (en) 1996-11-19
JPH08200006A (en) 1996-08-06
DE4436727A1 (en) 1996-04-18
JP3665394B2 (en) 2005-06-29
DE59504324D1 (en) 1999-01-07

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