DE1047581B

DE1047581B - Method and device for manufacturing turbine blades

Info

Publication number: DE1047581B
Application number: DEA22456A
Authority: DE
Inventors: John Harold Weaving; Richard Weck; Frank William Wotton Highfield
Original assignee: Austin Motor Co Ltd
Current assignee: Austin Motor Co Ltd
Priority date: 1955-04-09
Filing date: 1955-04-09
Publication date: 1958-12-24

Description

DEUTSCHESGERMAN

Die Erfindung bezieht sich auf ein Verfahren zum Herstellen von Turbinenschaufeln, bei dem ein über seine ganze Länge das Profil der herzustellenden Schaufel aufweisender Metallstreifen oder -stab beim Vorschub zuerst mit einem dickeren Teil seines Schaufelprofils mit der Amboß elektrode einer elektrischen Widerstandsstaucheinrichtung in Berührung gebracht wird und durch Anstauchen mit einem Fußteil gleichmäßigen Profils versehen wird, der anschließend durch Preßwerkzeuge in die endgültige Schaufelwurzelform geformt wird und durch Schmieden fertigbearbeitet wird.The invention relates to a method for manufacturing turbine blades, in which a its entire length the profile of the blade to be produced having metal strips or rods Feed first with a thicker part of its blade profile with the anvil electrode of an electrical one Resistance upsetting device is brought into contact and by upsetting with a foot part uniform profile is provided, which then by pressing tools in the final Blade root shape is formed and finished by forging.

Bei diesem Verfahren hat man bisher die bei der Widerstandserhitzung erzielte Temperatur zugleich auch für die Warmverformung beim Pressen der endgültigen Schaufelwurzelform auszunutzen gesucht. Dies führt aber häufig zu Schwierigkeiten, weil die Temperatur bei der komplizierten Formgebung der Schaufelwurzel möglichst genau die vorgeschriebene Schmiedetemperatur sein muß. Es wurde erkannt, daß die Ursache der häufig eintretenden Schwierigkeiten nicht nur in der zwischen Anstauchen und Nachverformung auftretenden Abkühlung unbekannten Ausmaßes, sondern vor allem darin begründet sind, daß bei der Widerstandserhitzung die Temperatur nicht in genauen Grenzen geregelt werden kann. Sie hängt nämlich von dem durch das Werkstück dargebotenen Widerstand und deshalb von unbeeinflußbaren Faktoren des Schaufelwerkstoffes ab, so daß sie von Schaufel zu Schaufel schwanken kann. Dieser Übelstand zeigt sich insbesondere bei Turbinenschaufeln geringer Dicke.In this process, the temperature achieved during the resistance heating has hitherto been available at the same time also sought to exploit the hot deformation when pressing the final blade root shape. However, this often leads to difficulties because the temperature in the complicated shape of the The blade root must be as precisely as possible the prescribed forging temperature. It was recognized that the cause of the frequently occurring difficulties not only in the between upsetting and Post-deformation occurring cooling of unknown extent, but mainly due to it are that with the resistance heating, the temperature is not regulated within precise limits can. This is because it depends on the resistance presented by the workpiece and therefore on the resistance that cannot be influenced Factors of the blade material, so that it can vary from blade to blade. This drawback is particularly evident in the case of turbine blades with a small thickness.

Dieser Übelstand wird gemäß der Erfindung bei dem eingangs genannten Verfahren dadurch behoben, daß an das Stauchen des Schaufelfußes eine Induktionsnacherhitzung auf Schmiedetemperatur zum Fertigformen angeschlossen wird. Diese Induktionsnacherhitzung gestattet, genau die gewünschte Schmiedetemperatur durch entsprechende Regelung der Dauer der Nacherhitzung herbeizuführen.According to the invention, this deficiency is remedied in the method mentioned at the beginning, that the upsetting of the blade root induction reheating to forging temperature for Finished molds is connected. This induction reheating allows exactly the desired Bring the forging temperature through appropriate control of the duration of the reheating.

Es ist an sich für die verschiedensten Werkstücke bekannt, die für eine Warmverformung notwendige Temperatur durch Induktionserhitzung herbeizuführen. Für die Herstellung von Turbinenschaufeln wurde eine solche Induktionserhitzung aber bisher nicht angewendet, da für den Stauchvorgang die elektrische Widerstandserhitzung einfacher und wirtschaftlicher ist. Man glaubte, auf eine zweite Heizvorrichtung bei der Herstellung des Schaufelfußes auch deshalb verzichten zu sollen, weil der zunächst unregelmäßig geformte Schaufelfuß eine schlechte elektrische Kopplung mit der Wicklung einer Induktionsheizung ergibt. Überraschend hat sich aber gezeigt, daß eine nachträgliche Induktionserhitzung Verfahren und Vorrichtung zum Herstellen von TurbinenschaufelnIt is known per se for a wide variety of workpieces that are necessary for hot forming Bring about temperature by induction heating. For the manufacture of turbine blades However, such induction heating has not yet been used, as the electrical heating is used for the upsetting process Resistance heating is easier and more economical. It was believed on a second heating device in the manufacture of the blade root should also be omitted because the initially irregularly shaped blade root a poor electrical coupling with the winding of an induction heater results. Surprisingly, however, it has been shown that subsequent induction heating Method and device for manufacturing turbine blades

Anmelder:Applicant:

The Austin Motor Company Limited, Northfield, Birmingham (Großbritannien)The Austin Motor Company Limited, Northfield, Birmingham (Great Britain)

Vertreter: Dr. W. Schalk und Dipl.-Ing. P. Wirth,Representative: Dr. W. Schalk and Dipl.-Ing. P. Wirth,

Patentanwälte, Frankfurt/M., Große Eschenheimer Str. 39Patent attorneys, Frankfurt / M., Große Eschenheimer Str. 39

John Harold Weaving, Knowle, Warwickshire,John Harold Weaving, Knowle, Warwickshire,

Richard Weck, Cambridge,Richard Weck, Cambridge,

und Frank William Wotton Highfield,and Frank William Wotton Highfield,

Broadway, Worcestershire (Großbritannien),Broadway, Worcestershire (UK),

sind als Erfinder genannt wordenhave been named as inventors

nicht nur die eingangs genannten Übelstände vermeiden läßt, sondern auch durchaus wirtschaftlich ist, weil der sonst vorkommende Ausschuß vermieden wird.not only avoids the abuses mentioned at the beginning, but is also quite economical, because the otherwise occurring rejects are avoided.

Die Erfindung bezieht sich auch auf eine Vorrichtung zur Durchführung des vorgenannten \⁷'erfahrens. Dabei wird von einer zweiteiligen, nachstehend Sekundärelektrode genannten Führungselektrode Gebrauch gemacht, wie sie an sich bei einer nicht mit Induktionserhitzung arbeitenden elektrischen Stauchpresse bekannt ist und deren Preßbacken aus der Werkstückbahn zurückziehbar sind. Bei der Vorrichtung zur Durchführung des Verfahrens gemäß der Erfindung ist außer dieser Führungselektrode vorgesehen, daß die Preßbacken, die Induktionsspule der Induktionsheizung und die Elektro-S tauchvorrichtung, die durch eine Amboß elektrode verkörpert wird, in Vorschubrichtung des Werkstückes hintereinander angeordnet sind. Dadurch ergibt sich die Möglichkeit, nach dem Anstauchen des Schaufelfußes das Werkstück mit dem Fuß in die Induktionsspule schnell hereinzuziehen, ohne daß ein merkliches Absinken der durch die Widerstandserhitzung erzielten Temperatur eintritt, und dann nach Erreichen der gewünschten Schmiedetemperatur den Schaufelfuß schnell zwischen die auseinandergezogenen Preßbacken wiederum ohne Wärmeverlust einzubringen.The invention also relates to an apparatus for carrying out the aforementioned ^'7 ' process. Use is made of a two-part guide electrode, hereinafter referred to as secondary electrode, as it is known per se in an electric sizing press that does not operate with induction heating and the press jaws of which can be withdrawn from the workpiece path. In the device for carrying out the method according to the invention it is provided in addition to this guide electrode that the pressing jaws, the induction coil of the induction heating and the electric immersion device, which is embodied by an anvil electrode, are arranged one behind the other in the direction of advance of the workpiece. This results in the possibility of quickly pulling the workpiece into the induction coil with the foot after the upset of the blade root, without a noticeable drop in the temperature achieved by the resistance heating, and then, once the desired forging temperature has been reached, the blade root quickly between the expanded jaws without introducing heat loss.

Es werden Ausführungen der Erfindung an Hand der Zeichnung beispielsweise dargestellt, und zwar zeigenThere are embodiments of the invention with reference to the drawing, for example, shown demonstrate

809 700/340809 700/340

Claims

3 43 4

1 to 4 are schematic representations of an embodiment. Such a device is shown in FIGS. 6 to 9 of the process of making a represents. A two-part Fühningselek-

Turbine blade, trode20 and an anvil electrode 21 similar to FIG

Fig. 5 is a schematic front view of the finished Fig. 1 arranged. The anvil electrode 21 is in the

Shovel and 5 drawing plane from the area of the advanced

6 to 9 in section and schematically, one of the strips 22 can be displaced. The parts of the four guide stages of a modified embodiment of the electrode 20 are apart and towards each other driving. move. A piece of a strip 22 is in its

1 to 5, a turbine blade from the longitudinal direction is horizontally by means of a pair of an io conveyor rollers 23 brought to a predetermined length. Between the conveyor metal strips 10 manufactured. As can be seen, has roller device 23 and the guide electrode 20 this strip 10 is the same over its entire length - are the embossing press 24 with embossing tools 25 and shaped cross-section, which is exactly with the transverse also an electrical induction heating winding 26 and Cut of the blade of a finished blade, cutting knife 27 attached.

matches. For example, the strip can be the same as 15 According to FIG moderate streamlined body cross-section after rolling 23 advanced so far until his forehead pattern of a wing. It is preferably at the end face with pressure on the anvil electrode 21 the predetermined length of a rolled-up grips, the parts of the two-part guide strip supply cut from suitable material ab- electrode 20 during this first process. 20 step of electrical upsetting hot deformation

The end of the strip 22 caused by electrical hot deformation to hold it between itself.

Upsetting of an end portion of the metal strip 10 will jam so that the enlarged blade root portion 28

carried out so that the stripe is formed between the.

Baking 11 of a two-part heavy copper After completion of this process step, the lead electrode is stored; the 25 parts of the guide electrode 20 are apart, and the two jaws 11 are designed so that they pinch the strip 10 strip 22 from the electrode 21 by means of the conveyor rollers 23 with a lateral pressing force. This process is sufficient to ensure good electrical contact is supported by a piston 29, which through the points, but nevertheless allows the strip 10 to penetrate the center of the anvil electrode 21 so far, sliding in the longitudinal direction between the jaws 11 30 up to the blade root 28 in the field of the electric shift. This is done by a stamp Irish induction heating coil 26, and here-12, which is attached so that it goes back to the one end to the position shown in Fig. 6,
of the strip 10 exerts a pressure by which the winding 26 is then excited in such a way that the other end 10 * of the latter comes into engagement with the blade root part 28 at the forging temperature of an anvil electrode 13. The electrical 35 brings, after which the strip 22 is withdrawn by means of the conveying resistance at the point of contact of the strip 10 with rollers 23 so far that the anvil electrode 13 causes the end part 10 * that the blade root part 28 in the area of the stamping press of the strip heats up. This heating effect verwerkzeuge 25 is. These then close in accordance with the cause in connection with the longitudinal direction - Fig. 8 above this foot part and shape it to its exerted pressure that the blade root shape final in contact with the anvil. After completion of the electrode 13 located end portion of the strip 10 to the embossing process, the tools 25 go again a hemispherical. Metal thickening will deform apart, and electrodes 20 and 21 will become. The removed by the electrical upsetting hot deformation; then the strip 22 is again pushed by means of the compression of the end part of the strip 10, which is pre-thickened by a certain amount, creating a foot part 14 (FIG than the remainder of the strip 10, which releases the molded root portion along with an un-airfoil. cut off the deformed part of the strip 22, which the

According to FIG. 1, the contact surface is formed by the anvil blade. From the position according to FIG. 9

Electrode 13 provided with a recess 15, which moves the knife 27 apart again, and the

the formation of the foot part 14 in the case of the electrical 50 electrodes 20 and 21 go into their working positions

Upsetting hot deformation supported. back, in which they are shown in Fig. 6, after which the

The next step in the process is to start the work cycle over.
Blade root part 14 in the field of an electrical induction by introducing the stage of reheating by ductile heating winding 16, as Fig. 3 shows electrical induction heating in the operation. As a result, the foot part 14 is switched to forging 55, which can be brought by an electrical upsetting temperature, whereupon the strip 10 is quickly introduced into the hot-deformed blade foot part 17 according to FIG. Pressing are brought to forging temperature so that the or stamping tools 18, which close in the direction of the shaping of the blade root in their final arrows drawn above the malleable foot-desired shape effected by pressing or stamping part 14, thereby give it the shape 60 can, without a subsequent machine, a blade root, as used to attach the z. B. machining is required.
Blade is needed on a turbine rotor.

According to FIGS. 4 and 5, the foot part 14 is given by the claims:
Embossing process fir tree-like wedges 19,

the blades in corresponding keyways on the turbine rotor 65 1. Method for producing turbine engagement, in which one over its entire length the

The invention also includes a device for profiling the blade to be manufactured

Manufacture of turbine rotor blades after the metal strip or rod in advance first

written procedures in a continuous operation with a thicker part of sea'öes Sch-aufeiftföfils

from a strip supply, e.g. B. a metal tape roll. 70 the anvil electrode of an electrical resistance

Stand upsetting device is brought into contact and by upsetting with a foot part uniform profile is provided, which then by pressing tools in the final S shovel is root-shaped and finished by forging, marked by induction reheating of the blade root (14) to forging temperature following the upsetting for finished molding.

2. Device for carrying out the method according to claim 1, characterized in that a known two-part guide electrode (20) is provided, the jaws of which are off the workpiece path are retractable, and that the pressing tools (pressing jaws 25), the Induk-

tion coil (26) of the induction heating and the electric upsetting device (anvil electrode 21) in Feed direction of the workpiece are arranged one behind the other.

Considered publications:

German Patent Nos. 884 447, 829 083, 059,405 657;

British Patent No. 708,672;

U.S. Patents Nos. 2,552,103, 2,275,763, 223 507, 1417 806;

"Werkstattstechnik und Maschinenbau", 41st year, issue 1 from January 1951, pp. 11 and 12;

"Technische Mitteilungen", Volume 46, Issue 6 from June 1953, pp. 170 and 171.

1 sheet of drawings