JP2014088857A - Friction welding method for blade in built-in blade wheel, friction welding device, and built-in blade wheel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a friction welding method for blades in a built-in blade wheel in which a connected surface between each of the blade bases arranged in rows at an outer periphery of a disk and a blade can be preliminary heated always in equal manner and under an appropriate reaching temperature and temperature distribution irrespective of adjoining blade arrangement and can be connected under a rational condition by the friction welding method.SOLUTION: Blades B are preliminary heated in order from one side by a heating coil 7 against each of blade bases Da arranged in rows on an outer periphery of a disk D and connected by a linear friction welding method. In the case that at the time of preliminary heating of each of the blades B, the blades B are not connected to the adjoining blade bases Da, the preliminary heating is performed upon arrangement of a dummy member Bd on the blade bases Da. With this arrangement as above, an eddy current under magnetic flux is generated at the dummy member Bd in the same manner as that of presence of the blades B.

Description

  The present invention relates to a blade friction welding method, a friction welding apparatus, and an integral blade wheel in an integrated impeller (blisk, bling), and more specifically, to a plurality of joint portions arranged at intervals on the outer periphery of a disk. In contrast, the present invention relates to a friction welding method for an integrated impeller in which blades are preheated by a heating coil in order from one side and joined by a friction welding method, a friction welding apparatus, and an integrated impeller manufactured by the friction welding method.

In the friction welding method, a pair of joining members, which are objects to be joined, are brought into contact with each other to cause a relative motion while applying a pressing force (upset pressure, forge pressure), and the joining surface is heated by the frictional heat generated at this time. This is a method of joining in a solid state. For example, in the technique of Patent Document 1, a friction welding method is used to repair an integrated impeller (blisk) applied as a compressor of an aircraft engine or a rotor of a turbine. This type of integrated impeller is configured by integrally arranging a large number of blades on the outer periphery of a disk. When any blade is damaged, it is repaired by cutting the damaged blade from the base (hereinafter referred to as the blade base) and joining a repair blade to the blade base after the cutting.
A linear friction welding (LFW) method is used for joining the repair blade, and the repair blade is brought into contact with the blade base and reciprocating on the straight line while applying a pressing force. The frictional heat is generated during the welding. Such a linear friction welding method is used not only for repairing an integrated impeller, but also for manufacturing an integrated impeller, and linear friction is applied to the blades in order against a large number of blade bases arranged on the outer periphery of the disk. Joined by pressure welding.

  Compared with other welding methods, the friction welding method described above can suppress the temperature rise of the joining member, so there is less thermal effect on the joining member, and oxides etc. at the joint are pushed out by friction as a defect. Has the advantage that it is difficult to occur. On the other hand, since a strong pressing force is required to soften the joining portion of the joining member by frictional heat, there is a problem that a manufacturing device is inevitably increased due to the need for a robust and mechanically large apparatus.

  As a solution to such a problem, a method has been proposed in which both or one of the joining members is preliminarily heated (hereinafter referred to as preheating) and then the friction welding method is performed. For example, Patent Document 2 discloses a technique using a rotary friction welding method. In this technique, a heating coil is disposed so as to surround a pair of joining members that form a rod shape, and after preheating the joining portions of both joining members by electromagnetic induction action of the heating coil, They are joined by relative rotation. This preheating reduces the pressing force required in the rotary friction welding method, thereby reducing the scale of the apparatus.

  Such preheating can be applied to bonding using a linear friction welding method, for example, bonding of a blade to the disk. In a state where the blade is abutted against the blade base, it is difficult to secure a space for arranging the heating coil. Therefore, first, the blade is spaced from the blade base, and a heating coil is inserted between the two members to preheat the joint surfaces facing each other. Next, after removing the heating coil from between both members, it is conceivable to take a procedure in which the blade is brought into contact with the blade base and the linear friction welding method is performed.

JP 2009-39746 A Japanese Patent Laid-Open No. 5-131280

  As is well known, in preheating using electromagnetic induction, high-frequency current is passed through a heating coil to generate magnetic flux between and in the joining member, and generate eddy currents that interfere with the magnetic flux in the joining member. As a result, the temperature of the joining surface of the joining member is increased. However, the magnetic flux generated by the high-frequency current is generated not only in the joining member but also in a nearby conductive member to generate an eddy current, and the eddy current in the joining member is weakened by that amount, preventing the temperature rise. .

  In the above-described integrated impeller, since the interval between the blades is narrow, eddy currents are generated not only in the blade to be joined by the current joining operation but also in the adjacent already joined blade. Since the joining of the blades is performed sequentially from one side to each blade base part arranged on the outer periphery of the disk, the first blade is preheated with no joined blades located on both sides. On the other hand, the second and subsequent blades (excluding the last blade) are preheated with the bonded blade positioned on one side, and the last blade is reserved with the bonded blade positioned on both sides. Heated.

  For this reason, according to preheating under the same conditions (same current value and energization time, etc.), vortices generated on the joint surfaces facing each other in the order of the first blade, the second and subsequent blades, and the last blade. The current is weakened, and the temperature reached is lowered accordingly.

  For example, a countermeasure for setting three types of preheating conditions in advance corresponding to the above three types of adjacent blade arrangements can be considered. In addition, a countermeasure using a heating coil having different specifications depending on the blade arrangement may be considered. However, since there are few adjustable requirements in the former measure, it is difficult to sufficiently equalize the ultimate temperatures of the joint surfaces, and the temperature distribution of each joint surface cannot be made equal. The same applies to the latter measure. In addition, when the joining operation of each series of blades is automated, a new work is required to replace the heating coil for each adjacent blade arrangement. Is hard to say.

Therefore, an error occurs in the ultimate temperature and temperature distribution of the joint surface depending on the blade arrangement, and the subsequent friction welding method cannot be performed under ideal conditions, and there is still room for improvement in this respect.
The present invention has been made to solve such problems, and an object of the present invention is to relate the joint surfaces of the blade bases and blades arranged on the outer periphery of the disk to the adjacent blade arrangement. Friction welding method of blade, friction welding apparatus and integral impeller which can always be preheated at equal and appropriate ultimate temperature and temperature distribution and can be joined by friction welding method under ideal conditions Is to provide.

  In order to achieve the above object, according to the first aspect of the present invention, the blades are sequentially preheated by a heating coil and joined by a friction welding method to a plurality of joining portions arranged at intervals on the outer periphery of the disk. In the friction welding method of the integrated impeller, when the blade is not joined to the joint part adjacent to the joint part to be joined this time, the dummy member whose conductivity is close to that of the adjacent joint part A dummy member disposing step, a preheating step in which preheating is performed by a heating coil after the dummy member is disposed, and after preheating, the dummy member is detached from the adjacent bonding portion and the blade is bonded by the friction welding method. And a friction welding process for joining to the part.

  According to a second aspect of the present invention, there is provided a friction welding method for an integrated impeller in which blades are sequentially preheated by a heating coil to a plurality of joining portions arranged at intervals on the outer periphery of a disk and joined by a friction welding method. In the dummy member placement step of placing dummy members each having an electrical conductivity similar to that of the blade at all joint portions except the joint portion where the blade is joined first, and after the dummy member placement, A first preheating step in which preheating is performed by a heating coil, a first friction welding step in which a blade is joined to the first joining portion by a friction welding method after the preheating in the first preheating step, The dummy member removing step of removing the dummy member arranged at the joining portion where the blade is joined next, and the removal of the dummy member after joining the blade to the joining portion In addition, after the second preheating step in which preheating is performed on the next bonding portion by the heating coil and the preheating in the second preheating step, the blade is bonded to the next bonding portion by the friction welding method. And 2 friction welding processes.

The invention of claim 3 is characterized in that a blade is applied as a dummy member.
The invention of claim 4 is characterized in that the dummy member has a simplified shape of the blade.
The invention according to claim 5 is characterized in that the dummy member arranging step arranges the dummy member in a state in which the dummy member is brought into contact with the joining portion of the disk.

In the invention of claim 6, the dummy member arranging step images the joint parts on both sides adjacent to the joint part to be joined this time, and the blade is joined to the joint parts on both sides based on the picked-up image. It is determined whether or not a dummy member is arranged at a joint portion where the blade is not joined.
According to a seventh aspect of the present invention, there is provided a disc that supports a disc having a plurality of joint portions arranged at intervals on the outer periphery, and that rotates each disc in a dynamic manner and sequentially sends each joint portion to a friction welding position. Driving means, friction welding means for joining the blade to the joining portion of the disk sent to the friction welding position by the friction welding method, and preliminary heating for preheating the blade by a heating coil prior to joining of the blade by the friction welding means When the blade is pre-heated by the heating means and the pre-heating means, when the blade is not joined to the joint portion adjacent to the friction welding position, a dummy member having a blade and an electrical conductivity approximate to the blade is disposed at the adjacent joint portion. And a member arranging means.
An eighth aspect of the invention is characterized by an integrated impeller manufactured by the blade friction welding method according to any one of the first to sixth aspects or the blade friction welding apparatus according to the seventh aspect.

  As described above, according to the blade friction welding method, the friction welding apparatus, and the integral impeller of the integrated impeller of the present invention, one side with respect to a plurality of joint portions arranged on the outer periphery of the disk. In the friction welding method for an integrated impeller in which the blades are preheated in order and joined by the friction welding method, the dummy is used when the blade is not joined to the joining portion adjacent to the joining portion to which the joining work is performed this time. The member is arranged, preheating is performed after the dummy member is arranged, and after the preheating, the dummy member is detached from the adjacent joint portion and the blade is joined to the joint portion to manufacture the integrated impeller.

  Therefore, when a blade is bonded to an adjacent bonding site, an eddy current due to a magnetic flux during preheating is generated in the bonded blade, and when a blade is not bonded to an adjacent bonding site, an eddy current due to the magnetic flux is generated. Occurs in the dummy member instead of the joined blade. For this reason, in any case, preheating can always be performed under the same conditions, and the joining surface of each disk joining portion and blade is always appropriately preheated, and the subsequent linear friction welding method is performed under ideal conditions. be able to.

It is a whole block diagram which shows the friction welding apparatus for implementing the friction welding method of the blade in the integrated impeller of this invention. It is a fragmentary perspective view which shows the arrangement | positioning state of the braid | blade, a heating coil, and a dummy member with respect to the braid | blade base part of a disk. (A)-(d) It is a figure which shows each process of joining the 1st braid | blade. (A)-(d) It is a figure which shows each process of joining the braid | blade after the 2nd sheet. (A)-(c) It is a figure which shows each process of joining the last braid | blade. It is a figure which shows the test result which compared the ultimate temperature of the joining surface by the side of a braid | blade by preheating with embodiment and the prior art. (A)-(f) It is a figure which shows each process of joining a braid | blade by the friction welding method of another example.

Hereinafter, an embodiment of a blade friction welding method and a friction welding apparatus in an integrated impeller embodying the present invention will be described.
The integrated impeller includes a disk D as a main body and a large number of blades B joined to the outer periphery of the disk D, and is made of a titanium alloy or a nickel alloy. On the outer periphery of the disk D, a large number of blade bases Da (joining parts) are arranged at intervals. Each blade base portion Da has an airfoil cross section corresponding to the blade B, and each blade B is joined to the blade base portion Da using the linear friction welding method of the present invention to complete an integrated impeller.
However, the shape of the integrated impeller is not limited to this. For example, the blade B may be directly joined to the outer peripheral surface of the disk D without providing the blade base Da on the outer periphery.

  FIG. 1 is an overall configuration diagram showing a friction welding apparatus for carrying out a blade friction welding method in an integrated impeller of the present invention, and FIG. 2 shows an arrangement state of a blade B, a heating coil, and a dummy member with respect to a blade base Da. It is a fragmentary perspective view. Hereinafter, for convenience of explanation, the up and down direction in FIG. 1 is defined as up and down, the left and right direction in FIG.

  As a whole, the linear friction welding apparatus is a disk drive unit 1 (disk drive means) that sequentially feeds each blade base Da to the friction welding position S (set above the disk D) by dynamic rotation while supporting the disk D. Prior to the joining of the blade B, the friction welding part 2 (friction welding means) that holds the blade B above the friction welding position S and joins the blade B to the blade base Da sent to the friction welding position S. A preheating unit 3 (preheating unit) that performs preheating by the heating coil 7, a dummy member operating unit 4 (dummy member arranging unit) that arranges the dummy member Bd as necessary in the adjacent blade base Da during preheating, And a control unit 5 that integrally controls the operation of each of the mechanism units 1 to 4 and is disposed on the base 6 of the linear friction welding apparatus.

A disk D of the integrated impeller is detachably fixed to the drive mechanism 8 of the disk drive unit 1. The disk D is supported in such a posture that one side faces rearward, and is rotationally driven counterclockwise by the drive mechanism 8 when viewed from the rear. The rotational drive pitch of the disk D corresponds to the interval between the blade bases Da, so that each blade base Da is sequentially sent to the friction welding position S.
The grip 9 of the friction welding part 2 is disposed above the friction welding position S, and the blade B is detachably held by the grip 9. In this embodiment, every time the joining of the blade B to the blade base Da is completed, the worker causes the gripping part 9 to grip a new blade B. However, the present invention is not limited to this, and the work is automated. May be.

  The grip portion 9 is supported by a hydraulic mechanism 10, and the grip portion 9 is driven in the vertical direction and the front-rear direction by the hydraulic mechanism 10 for joining the blades B by the linear friction welding method. When carrying out the linear friction welding method, the gripping portion 9 is lowered from the position indicated by a two-dot chain line in FIG. 1, and the blade B is brought into contact with the blade base Da of the disk D at the friction welding position S so as to join both joint surfaces. A pressing force is applied to. Then, in this state, the blade B is reciprocated in the front-rear direction together with the grip portion 9, thereby generating frictional heat on the joint surfaces and joining them.

The preheating unit 3 is arranged at a rear position of the disk drive unit 1. A linear motion stage 11 of the preheating unit 3 is installed on the base 6, and a power supply box 12 is disposed on the linear motion stage 11 and is transported in the front-rear direction. A support arm 13 extends horizontally from the power supply box 12 toward the front, and the heating coil 7 is supported at the tip of the support arm 13.
The heating coil 7 is moved in the front-rear direction together with the power supply box 12, and is inserted between the blade base Da and the blade B at the friction welding position S as shown by phantom lines in FIG. At the rear stroke end, as shown by a solid line, the rear end is separated from between the blade base Da and the blade B (hereinafter referred to as a retracted position).

  Although not shown, a high-frequency induction heating circuit is accommodated in the power supply box 12, and this high-frequency induction heating circuit is connected to a high-frequency power supply 15 via a power line 14 and via a bus bar (not shown) built in the support arm 13. And electrically connected to the heating coil 7. The high frequency induction heating circuit causes a high frequency current to flow through the heating coil 7 through the bus bar when power is supplied from the high frequency power supply 15. As a result, magnetic flux is generated between the heating coil 7 and the blade base Da and the blade B, and inside the blade base Da and the blade B. For this reason, eddy currents that block the magnetic flux are generated in the blade base Da and the blade B, and the joint surfaces of the blade base Da and the blade B are heated.

  The dummy member operation unit 4 is disposed on each of the left and right sides of the preheating unit 3. In FIG. 1, the right dummy member operation unit 4 is omitted and only the left dummy member operation unit 4 is shown. However, since the left and right dummy member operation units 4 have the same configuration, the left dummy member operation unit 4 will be described below. Is described. Similar to the power supply box 12 of the preheating unit 3, the transfer table 16 of the dummy member operation unit 4 is arranged on the dummy linear motion stage 17 and is transferred in the front-rear direction. A dummy support arm 18 extends horizontally from the transfer table 16 toward the front, and a dummy member Bd is supported at the tip of the dummy support arm 18.

In the present embodiment, the blade B itself to be joined is used as the dummy member Bd. For example, a blade B selected from a large number of blades B manufactured for joining to the disk D, or a blade B broken and discarded during the operation of the integrated impeller is used. Is fixed to the tip of the dummy support arm 18 as a dummy member Bd.
The dummy member Bd is transferred along the dummy linear motion stage 17 together with the transfer table 16, and is disposed immediately above the blade base Da adjacent to the left side of the friction welding position S as shown in FIG. , And called the insertion position), the rear stroke end is separated from directly above the blade base Da (hereinafter referred to as the retraction position). The operation when the dummy member Bd at the insertion position is switched to the retracted position by the dummy linear movement stage 17 in this way is defined as “detachment”.

In the insertion position, the dummy member Bd is held in the same posture as the blade B when joined to the blade base Da, that is, in a normal posture directed to the center of the disc D, and the disc is used for smooth transfer of the dummy member Bd. The dummy member Bd is slightly separated from the blade base Da of D.
However, the present invention is not limited to using the blade B as the dummy member Bd, and the posture of the dummy member Bd at the insertion position is not limited to the above. For example, since titanium alloy and nickel alloy, which are the materials of blade B, are expensive, a cheaper material with similar conductivity can be selected from the same type of alloys, and the dummy member Bd can be manufactured using that material. Instead of using the blade B, a flat dummy member Bd with a simplified wing-shaped cross section may be used. Further, the posture of the dummy member Bd at the insertion position may be changed from the above, or the dummy member Bd may be brought into contact with the blade base Da of the disk D.

  As described below, the dummy member Bd at the time of preheating generates an eddy current by the magnetic flux of the heating coil 7 at the insertion position. In this embodiment, since the blade B is used as the dummy member Bd, the eddy current generated in the dummy member Bd at this time is joined to the original blade B (specifically, the blade base Da on the left side of the friction welding position S). The situation is similar to the eddy current generated in blade B).

The left dummy member operation unit 4 is configured as described above, and the right dummy member operation unit 4 has the same configuration, except that the right dummy member operation unit 4 moves the dummy member Bd to the insertion position. In addition, the dummy member Bd is arranged immediately above the blade base Da adjacent to the right side of the friction welding position S.
The control unit 5 is electrically connected to the drive mechanism 8 of the disk drive unit 1, the hydraulic mechanism 10 of the friction welding unit 2, the power supply box 12 of the preheating unit 3, and the transfer table 16 of the dummy member operation unit 4. Has been. These mechanism units 1 to 4 are operated based on a command from the control unit 5, and the blades B are sequentially joined to the respective blade bases Da of the disk D through a series of work procedures described below.

  Further, the control unit 5 is provided with an imaging device 19, and a peripheral region E including the friction welding position S is imaged from the front by the imaging device 19, and the captured image is input to the control unit 5. Based on the analysis result of the captured image, the control unit 5 determines whether or not the joined blade B is located on the blade base Da located on both sides of the friction welding position S. And according to the determination result, at the time of preliminary heating, the transfer table 16 is driven and controlled so that the dummy member Bd is appropriately transferred to the insertion position.

Next, the joining operation of the blade B performed by the friction welding apparatus configured as described above will be described with reference to FIG. Although not specifically stated, all the following work procedures are based on commands from the control unit 5. 3A to 3D are views of the periphery of the friction welding position S as viewed from the rear, and the disk D is driven to rotate counterclockwise to feed the blade base Da, and the depth direction of the paper surface. From this, the imaging device 19 captures the area E.
As a whole work, the blade B is joined to the blade base Da of the disk D located at the friction welding position S by the linear friction welding method, and the disk D is rotationally driven dynamically to form new blade bases Da in order. It is carried out by repeating the joining of the blade B while feeding it to the friction welding position S. As a result, the blade B is joined to each blade base portion Da of the disk D in order along the circumferential direction from one side, and finally the blade B is joined to all the blade base portions Da to complete the operation. Hereinafter, the procedure from the joining of the first blade B to the joining of the last blade B will be described sequentially.

  In an initial state before the start of work, the blade B is not joined to all the blade bases Da of the disk D fixed to the drive mechanism 8, and any blade base Da is located at the friction welding position S. . Further, the blade B is gripped by the gripping portion 9 and positioned above the solid line in FIG. 1, and the heating coil 7 and the dummy member Bd are switched to the retracted position.

First, the control unit 5 lowers the blade B together with the gripping unit 9 so that the joining surface of the blade B and the joining surface of the blade base Da located at the friction welding position S are set to a preset interval. Then, the presence / absence of the blades B on the left and right sides of the friction welding position S is determined based on the captured image of the region E.
As shown in FIG. 3A, at this time, the blade B is not joined to any blade base Da on both sides. For this reason, both the left and right transfer bases 16 are moved forward to switch the respective dummy members Bd to the insertion positions (dummy member arranging step). In parallel with this, the feeding box 12 is moved forward, and the heating coil 7 is switched to the insertion position.

As a result, as shown in FIG. 3B, the heating coil 7 is inserted between the blade base Da and the blade B at the friction welding position S, and the dummy members Bd are respectively formed on the left and right blade bases Da. Be placed. In this state, a high-frequency current is passed through the heating coil 7 by a high-frequency induction heating circuit to preheat the joint surface between the blade base Da and the blade B (preheating step).
Various conditions such as a current value and energization time at the time of preheating are obtained in advance by a test. In the present embodiment, the test is performed in a state in which the blades B that have already been joined are positioned on both the left and right sides of the friction welding position S, and eddy currents are generated in the left and right blades B by the magnetic flux during preheating. Based on the various conditions obtained by such a test, energization control of the heating coil 7 is performed in the above-described preheating step. This point is the same for all the second and subsequent blades B, and preheating is performed under the same conditions as the first blade B.

When the preliminary heating is completed, the power feeding box 12 is moved backward by the linear motion stage 11 to switch the heating coil 7 to the retracted position. Thereafter, as shown in FIG. 3 (c), the blade B is lowered together with the grip portion 9, the joining surface is brought into contact with the joining surface of the blade base Da, and the blade B is reciprocated back and forth while applying a pressing force. Both joint surfaces are joined by frictional heat (friction welding process).
Thereafter, as shown in FIG. 3D, the grip 9 is raised, and the left and right transfer bases 16 are moved rearward to switch the dummy member Bd to the retracted position. Thus, the joining of the first blade B is completed, and for the joining of the next blade B, the disk D is rotationally driven at a pitch corresponding to the interval of the blade base Da, and the adjacent right blade base Da is connected to the friction welding position S. Send to.

The work procedure is not limited to the above, and can be arbitrarily changed within a range that does not hinder the work. For example, in the above-described order, the presence or absence of the blade B is determined based on the captured image after the blade B is arranged at the friction welding position S. However, the order of both may be reversed. Similarly, the dummy member Bd is detached after the blade B is joined to the blade base Da, but the order of these can also be reversed.
For the second and subsequent blades B, the same procedure as that of the first blade B is basically employed, but only the operation state of the dummy member Bd is different. That is, after the next blade B is gripped by the gripper 9 by the operator, the controller 5 lowers the blade B together with the gripper 9 and determines the presence or absence of the blades B on both sides of the friction welding position S from the captured image. .
In this joining operation, as shown in FIG. 4A, the joined blade B is positioned on the left blade base Da. For this reason, as shown in FIG. 4B, only the right dummy member Bd is switched to the insertion position (dummy member placement step), and the heating coil 7 is switched to the insertion position in parallel.

  Next, preheating is performed by supplying a high-frequency current to the heating coil 7 (preheating process), and after completion, the heating coil 7 is switched to the retracted position. Then, as shown in FIG. 4C, after the blade B is lowered and joined to the blade base Da by the linear friction welding method (friction welding process), the dummy member Bd is retracted as shown in FIG. 4D. Switch to position. Thus, the joining of the second blade B is completed, and the disk D is rotationally driven to send the adjacent right blade base Da to the friction welding position S.

  Similar to the second blade B described above, the joined blade B is located on the left side of the friction welding position S when the third and subsequent blades B are joined. Therefore, at the time of preheating, only the right dummy member Bd is switched to the insertion position, and a duplicate description is omitted, but the operation is performed according to the procedure of FIGS. 4A to 4D which is exactly the same as that of the second blade B. To do.

When joining the last blade B, as shown in FIG. 5A, the joined blade B is located at any of the left and right blade bases Da at the friction welding position S. For this reason, as shown in FIG. 5B, the heating coil 7 is switched to the insertion position while the left and right dummy members Bd are held in the retracted position, and preheating is performed (preheating process).
Then, after switching the heating coil 7 to the retracted position and joining the blade B to the blade base Da (friction welding process) as shown in FIG. 5C, all the joining operations of each blade B are completed. To do.

Next, the implementation status of preheating for each blade B implemented as described above will be compared.
In the preliminary heating for the first blade B, the joined blade B is not located on either of the left and right sides of the friction welding position S. However, as shown in FIG. The member Bd is disposed. In the preheating for the second and subsequent blades B (excluding the last blade B), the joined blade B is not located on the right side of the friction welding position S. As shown in FIG. Instead of the right blade B, a dummy member Bd is arranged. In the preliminary heating for the last blade B, as shown in FIG. 5A, the joined blade B is located on both the left and right sides of the friction welding position S.

  Accordingly, when any of the blades B is preheated, either the blade B or the dummy member Bd that has been joined is always disposed on both the left and right sides of the blade B, and eddy currents caused by magnetic flux are applied to the blade B and the dummy member Bd. Preheating is performed while generating. In particular, in this embodiment, since the blade B itself is used as the dummy member Bd, the dummy member Bd when receiving the magnetic flux is in an eddy current generation state that is almost the same as that of the joined blade B. As a result, the dummy member Bd generates an eddy current even when the joined blade B is not located on either side or the right side of the friction welding position S. Therefore, preheating of all the blades B is always performed under the same condition. It will be.

  As described above, the preheating conditions (current value, energization time, etc.) are set based on a test in which the blades B that have already been bonded are arranged on both sides. Can be implemented. As a result, regardless of the adjacent blade arrangement, the joint surfaces of the blade bases Da and the blades B can always be preheated at an equal and appropriate ultimate temperature.

  FIG. 6 is a diagram showing test results in which the ultimate temperature of the joint surface on the blade B side by preheating is compared between the present embodiment and the prior art. The ultimate temperature is measured as the center temperature of the joint surface. As shown in this figure, in the prior art, when there is no blade B joined on both sides (single wing in the figure), when the blade B joined on one side is located (one wing in the figure), The center temperature decreases in the order in which the joined blades B are located on both sides (there are both blades in the figure). On the other hand, in the present embodiment, the center temperature corresponding to both blades of the prior art is obtained in any of the single blade, single blade, and both blades, and it can be seen that the temperature difference due to the difference in blade arrangement can be eliminated.

In addition, the fact that the preheating is always performed under the same condition not only eliminates the temperature difference but also makes the temperature distribution on the joint surface uniform. Therefore, according to this embodiment, regardless of the arrangement of adjacent blades, the joint surfaces of the blade base portions Da and the blades B can be always preheated at an equal and appropriate ultimate temperature, and the subsequent linear friction welding method can be performed. The blade B can be satisfactorily bonded to each blade base Da by carrying out under ideal conditions.
In addition, since a countermeasure for replacing the heating coil 7 corresponding to the adjacent blade arrangement as described in [Problems to be Solved by the Invention] is not required, the work process due to the countermeasure is prevented from being complicated. The effect that it is possible is also acquired.

  Further, it is determined based on the image captured by the imaging device 19 whether or not the joined blade B is positioned on both the left and right sides of the friction welding position S. For this reason, the presence or absence of the joined blade B can be accurately determined by the control unit 5, and when the blade B is not located, the dummy member Bd can be reliably disposed instead. Therefore, it is possible to prevent a situation in which the dummy member Bd is not disposed at the position even though the joined blade B is not located, and thus it is possible to always appropriately perform the preheating.

However, the present invention is not limited to the method of determining the presence or absence of the blade B from the captured image. For example, since the control unit 5 recognizes the dynamic drive count of the disk D from the start of the work, it is possible to determine the number of blades B to be joined by this joining work from this drive count. . Therefore, the dummy member Bd may be switched according to the determination result.
Furthermore, as described above, the dummy member Bd can be made of an inexpensive material whose conductivity is approximated without diverting the blade B itself, or a flat dummy member Bd having a simplified wing-like cross section can be used. It is. In these cases, since the material cost and the processing cost of the dummy member Bd can be reduced, another effect that the manufacturing cost of the entire friction welding apparatus can be reduced is obtained.

  On the other hand, since the dummy member Bd is slightly separated from the blade base Da of the disk D at the insertion position as described above, the effect that the dummy member Bd can be smoothly transferred without contacting the blade base Da is obtained. However, the present invention is not limited to this. For example, the dummy member Bd may be brought into contact with the blade base Da at the insertion position.

  As is apparent from the above description, the right dummy member Bd is transferred to the insertion position every time the blade B is preheated from the start of the operation, and an eddy current is generated to raise the temperature. Each time the preheating is completed, the right dummy member Bd is naturally cooled, but the temperature rises by the next preheating before the temperature sufficiently decreases. For this reason, the right dummy member Bd gradually accumulates heat and reaches a considerably high temperature during the preliminary heating of the second blade B from the end. When the last blade B is preheated, since the joined blade B is also located on the right side of the friction welding position S, the right dummy member Bd is not used, but the joined blade B is joined first. Since it is the blade B, the temperature is sufficiently lowered.

Therefore, for example, when comparing the last blade B from the last blade B with the last blade B, the temperature of the member located on the right side (joined blade B or dummy member Bd) during the preheating is significantly different. Due to this, there is a possibility that a disparity that cannot be ignored arises in the generation state of eddy current, and the preheating conditions are different.
When the dummy member Bd is brought into contact with the blade base Da at the insertion position, a part of the heat of the dummy member Bd is released to the disk D side, so that the temperature rise of the dummy member Bd can be suppressed. For this reason, the eddy current disparity caused by the temperature difference can be reduced, and as a result, the preheating can be performed under more uniform conditions.

By the way, in this embodiment, the dummy member Bd is disposed as necessary for the adjacent blade base Da for each preheating of each blade B. However, the present invention is not limited to this, and each blade base Da of the disk D in advance. Each of the dummy members Bd may be arranged in the upper part. Hereinafter, the joining operation of the blade B of this another example will be described with reference to FIG.
In addition, what is necessary is just to use the friction welding apparatus described by embodiment shown in FIG. However, since the dummy member operation unit 4 and the imaging device 19 are unnecessary, the mechanism may be omitted.

First, the disk D of the integrated impeller is fixed to the drive mechanism 8 of the disk drive unit 1, and the dummy members Bd are respectively arranged on all the blade bases Da except for one blade base Da (dummy member placement step). . Since the blades B arranged as described below are sequentially removed according to the progress of the work, a simple fixing method for the dummy member Bd is desirable so that the blades B can be easily removed. For example, the dummy member Bd is fixed to the blade base Da by spot welding or the like. Hereinafter, the operation of removing the dummy member Bd arranged on the blade base Da in this way is defined as “removal”.
When the arrangement of each blade B is completed, the disk D is rotated by the drive mechanism 8 to transfer the blade base Da where the dummy member Bd is not arranged to the friction welding position S. As shown in FIG. 7A, the blade base Da becomes the blade base Da that joins the blade B first. The arrangement of the dummy member Bd on each blade base Da may be performed in the state of the disk D alone, and then the procedure of fixing the disk D to the drive mechanism 8 of the disk drive unit 1 may be taken.

Next, the blade B is lowered and the heating coil 7 is switched to the insertion position. As shown in FIG. 7B, since the dummy members Bd are already arranged on both sides of the blade base Da at the friction welding position S, preheating is performed in this state (first preheating step).
After the preheating is completed, the heating coil 7 is switched to the retracted position, and as shown in FIG. 7C, the blade B is joined to the blade base Da by the linear friction welding method (first friction welding process).

  Thereafter, when the gripping portion 9 is raised, the first blade B is completely joined, and the disk D is rotationally driven to join the next blade B, and the adjacent right blade base Da is sent to the friction welding position S. . Since the dummy member Bd is disposed on the blade base Da of the disk D to be joined next, the dummy member Bd is removed as shown in FIG. 7D (dummy member removing step). For example, in the case of the spot welding, the dummy member Bd is separated from the blade base Da by cutting the weld.

  Next, the next blade B is grasped and lowered by the grasping portion 9, and as shown in FIG. 7E, the heating coil 7 is switched to the insertion position and preheating is performed again (second preheating step). . Thereafter, the heating coil 7 is switched to the retracted position, and then the blade B is lowered and joined to the blade base Da as shown in FIG. 7 (f) (second friction welding process). Thus, the joining of the second blade B is completed, and the disk D is rotationally driven to send the adjacent right blade base Da to the friction welding position S.

  Similar to the second blade B, the dummy member Bd is disposed on the blade base Da when the third and subsequent blades B are joined. For this reason, each time the blade B is joined, the dummy member Bd is first removed in accordance with the procedure shown in FIGS. 7D to 7F, and then the preliminary heating and friction welding operations are performed. The blade B is joined to all the blade base portions Da.

In the joining operation of the blade B of this other example, as shown in FIG. 7A, in the preliminary heating for the first blade B, dummy members Bd are arranged on both the left and right sides of the friction welding position S. In the preliminary heating for the second and subsequent blades B (excluding the last blade B), as shown in FIG. 7D, the joined blade B is located on the left side of the friction welding position S, and on the right side. A dummy member Bd is arranged. In the preliminary heating for the last blade B, the joined blade B is located on both the left and right sides of the friction welding position S.
Therefore, in the case where any blade B is preheated, either the blade B or the dummy member Bd that has been joined is necessarily disposed on the left and right sides. Thus, although not redundantly described, the same effects as those of the above-described embodiment can be obtained in this other example.

This is the end of the description of the embodiment, but the aspect of the present invention is not limited to this embodiment. For example, in the above embodiment, the blades B are joined to the respective blade bases Da arranged on the outer periphery of the disk D in order from one side. However, the present invention is not limited to this, and the blades B are attached to the respective blade bases Da according to different orders. You may make it join.
Further, in the above embodiment, the blades B are sequentially joined to the respective blade bases Da arranged on the outer periphery of the disk D by the linear friction welding method, but not only such an annular joining object but also a linear shape. It can also be applied to other joining objects. That is, in this case, the joining members are joined in order from one side to the joining portions (corresponding to the blade base Da) arranged in a straight line at intervals to the joining object. I will do it. In the first joining member, the joined members that have been joined are not located on both sides, whereas in the second and subsequent joining members, the joined members that have been joined are located on one side. Therefore, when the first joining member is joined, if a dummy member is disposed on one side thereof, the preheating of all the joining members can be performed under the same conditions as in the above embodiment.

  In the above-described embodiment, all the operations other than the operation of gripping the blade B by the grip portion 9 are automated by the friction welding apparatus, but the present invention is not limited to this. For example, the operator visually confirms whether the blade B is positioned at the blade base Da adjacent to the friction welding position S, and the operator manually inserts and removes the dummy member Bd according to the result. May be. The same applies to the insertion and removal operations of the heating coil 7 and may be performed manually by the operator. Moreover, you may make it operate | move each mechanism part 1-4 according to switch operation by an operator, without based on the command from the control part 5 for a series of work procedures.

1 Disk drive unit (disk drive means)
2 Friction welding part (friction welding means)
3 Preheating part (preheating means)
4 Dummy member operation part (dummy member placement means)
7 Heating coil D Disk Da Blade base B Blade Bd Dummy member

Claims (8)

In the friction welding method for an integrated impeller in which the blades are sequentially preheated by a heating coil and joined by a friction welding method to a plurality of joining sites arranged at intervals on the outer periphery of the disk.
A dummy member placement step of placing a dummy member having an electrical conductivity similar to that of the blade in the adjacent joint portion when the blade is not joined to the joint portion adjacent to the joint portion to be joined this time When,
A preheating step of performing preheating by the heating coil after the placement of the dummy member;
And a friction welding step of separating the dummy member from the adjacent joint portion after the preheating and joining the blade to the joint portion by a friction welding method. Friction welding method. In the friction welding method for an integrated impeller in which the blades are sequentially preheated by a heating coil and joined by a friction welding method to a plurality of joining sites arranged at intervals on the outer periphery of the disk.
A dummy member placement step of placing dummy members each having an electrical conductivity similar to that of the blade at all joint portions except the joint portion where the blade is first joined;
A first preheating step of performing preheating by the heating coil on the first joint portion after the dummy member is disposed;
A first friction welding process in which the blade is joined to the first joining portion by friction welding after the preheating in the first preheating process;
A dummy member removing step of removing a dummy member disposed at a joining portion where the blade is joined next after joining the blade to the first joining portion;
A second preheating step of performing preheating by the heating coil on the next bonding site after the removal of the dummy member;
Friction of blades in an integrated impeller characterized by comprising a second friction welding step of joining the blades to the next joining site by friction welding after the preliminary heating in the second preheating step Pressure welding method.   The blade friction welding method according to claim 1 or 2, wherein the blade is applied as the dummy member.   The blade friction welding method according to any one of claims 1 to 3, wherein the dummy member has a shape obtained by simplifying the shape of the blade.   5. The blade in an integrated impeller according to claim 1, wherein in the dummy member arranging step, the dummy member is arranged in contact with a joint portion of the disk. Friction welding method.   In the dummy member placement step, images of the joint portions on both sides adjacent to the joint portion to be joined this time are taken, and whether or not the blade is joined to the joint portions on both sides based on the captured image. The method of friction welding of blades in an integrated impeller according to any one of claims 1, 3, and 4, wherein the dummy member is disposed at a joint portion where the blade is not joined. A disk driving means for rotating the disk in an orderly manner and rotating each disk to the friction welding position while supporting a disk having a plurality of bonding sites arranged at intervals on the outer periphery;
Friction welding means for joining a blade by a friction welding method to a joining portion of the disk sent to the friction welding position;
Preheating means for preheating the blade with a heating coil prior to joining of the blade by the friction welding means;
When the blade is pre-heated by the pre-heating means, if the blade is not joined to the joint portion adjacent to the friction welding position, a dummy member having an electrical conductivity similar to that of the blade is disposed at the adjacent joint portion. A friction welding apparatus for blades in an integrated impeller characterized by comprising dummy member disposing means.   An integrated impeller manufactured by the blade friction welding method according to claim 1 or the blade friction welding device according to claim 7.

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