JPH05171901A - Dividing and integrally molding of turbine rotor - Google Patents

Abstract

PURPOSE:To provide a dividing and molding method of a turbine rotor with which a turbine blade having a large curvature and a complicated shape can be installed at a small pitch and with which turbine efficiency can be improved. CONSTITUTION:A turbine disc 5 on which turbine blades 2 are embedded is divided into two parts in the axial direction, divided turbine discs 3, 4 are put to slide in different directions relative to the turbine blades 2, so embedding parts 2b of the turbine blades are engaged with embedding grooves 3a, 4a of the turbine disc, and the divided turbine discs 3, 4 are connected to each other by screws 6, for example.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an aircraft, a ship,
Alternatively, the present invention relates to a method for dividing and integrally molding a turbine rotor used for manufacturing a turbine rotor that is a component of a gas turbine for an automobile.

[0002]

2. Description of the Related Art Conventionally, there are various methods for manufacturing a turbine rotor as described above. For example, as shown in FIG. 13, on the outer periphery of a turbine disk 101 forming a central portion of a turbine rotor 100, Turbine blade 1
Implanting groove 101a for attaching 02 is formed by the number of turbine blades 102, and an embedding portion 102 provided at a base end portion 102a of the turbine blade 102.
b is an implantation groove 101a of the turbine disk 101
A split molding method has been put into practical use in which a large number of turbine blades 102 are radially planted on the outer circumference of the turbine disk 101 by fitting the blades so that they are slid in the axial direction.

On the other hand, in recent years, as materials for turbine rotors, ceramic materials and carbon have been used in place of conventional high Ni alloy steel and Ni-based heat resistant alloys in order to further improve heat resistance and corrosion resistance and reduce weight. Fiber-reinforced carbon composite materials (hereinafter referred to as C / C composites) are being applied, and the split molding method of the turbine rotor described above is applicable not only to metal materials but also to ceramic materials and C / C composites. is there.

In addition, the turbine rotor as described above is C /
For integrally molding with C composite, for example, a machine cutting method of cutting a blade portion into a predetermined shape by machine cutting from a large disc-shaped C / C composite material, thermosetting resin such as phenol resin on carbon fiber As shown in FIGS. 14 (a) and 14 (b), a prepreg 112 for a wheel that forms a main body wheel portion of a turbine rotor laminated on a lower mold 111 by using a prepreg impregnated with
A blade prepreg 113 is laminated around the periphery of the blade to form the blade portion 114 radially.
After setting the blade-shaped die 115 having the taper portion 115a between the four, the taper portion 116a provided in the upper die 116 is overlapped with the taper portion 115a of the die 115 and pressure P is applied to the wheel prepreg. At the same time as vertically pressing the wheel portion in which 112 is laminated, the blade-shaped mold 115 is pressed in the center direction to perform hot press molding, and then C / C treatment is performed in the radial direction pressing method. The wheel and blade prepregs 112 and 113 are laminated in the same manner as described above, and as shown in FIG.
Blade-shaped mold 117 divided into two for each of 14
a and 117b are set, and each of them has a serrated slope 118.
By applying pressure P to the upper mold 118 and the lower mold 119 provided with a and 119a, the wheel prepreg 112
At the same time pressing the wheel part that laminated the
A vertical pressing method has been applied in which the blade prepreg 113 forming the blade portion 114 is hot-pressed so as to be pressed in the thickness direction of the blade and then subjected to C / C treatment.

[0005]

However, in the conventional split forming method for a turbine rotor described above, in the case of a blade having a large curvature, the width W of the base end portion of the turbine blade 102 shown in FIG. 13 is large. Therefore, there is a problem that the efficiency of the turbine is reduced because the blade planting pitch must be increased.

In the conventional method of integrally molding a C / C composite turbine rotor described above, in the case of the mechanical cutting method, the carbon fiber as the reinforcing material is cut by the mechanical cutting, so that the strength of the blade portion is increased. descend. Further, in the case of a radial pressing method or a vertical pressing method using a die or jig having a complicated shape, the forming work is complicated, and it is not applicable to forming a blade having a complicated shape with a large twist or curvature. In addition to being difficult, there is a problem that the direction of fibers is disturbed due to the lengthening of the pushing stroke during molding, which may reduce the strength, and elimination of these problems will improve the quality and productivity of the turbine rotor. It was a problem in.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems. A turbine rotor having a large degree of curvature can be attached at a fine pitch, thereby improving the turbine efficiency. An object of the present invention is to provide a split molding method and a method for integrally molding a C / C composite turbine rotor, which is easy to mold even with a blade having a complicated shape with a fine pitch and a curved shape, and which does not have strength reduction. I am trying.

[0008]

According to a method of split molding a turbine rotor according to the present invention, a fitting portion formed at a base end portion of a turbine blade is slidably fitted into a fitting groove formed in a turbine disk. In the method of molding a turbine rotor, wherein the turbine blade is planted in the turbine disk, the turbine disk is divided into two in the axial direction, and the divided turbine disks are slid from different directions with respect to the turbine blade. It is characterized in that after the fitting portion of the turbine blade is fitted in the fitting groove, the divided turbine disks are connected to each other. In the embodiment, the turbine disk and the turbine blade are C-shaped.
/ C composite, in the state where the turbine blade is implanted in the turbine disk, after impregnating the pitch or liquid resin of the carbon material raw material between the implantation groove of the turbine disk and the implantation portion of the turbine blade, It is characterized in that the C / C processing is performed, and the configuration of such a split forming method for a turbine rotor is used as a means for solving the above-mentioned conventional problems.

Further, in the method for integrally molding a C / C composite turbine rotor according to the present invention, the blade prepreg forming the blade portion of the turbine rotor is in a state where its end portion extends in the center direction of the turbine rotor. After arranging a plurality of blade molds sandwiched in the molding gap along the outer circumference of the ring-shaped jig, the extended end of the blade forming prepreg is multi-divided in the axial direction of the turbine rotor, and the turbine is It is characterized in that the wheel prepregs are laminated while being dispersed between the wheel prepregs forming the main body wheel portion of the rotor, and in the embodiment, instead of the blade mold and the ring jig. It is characterized by using a rubber molding die made from the master model,
The configuration of such a method for integrally forming a turbine rotor is used as means for solving the above-mentioned conventional problems.

[0010]

In the split forming method of the turbine rotor according to the present invention, the turbine blade is not slid from one side and fitted into the turbine disc, but the turbine disc divided into two in the axial direction is sandwiched from both sides of the turbine blade. By sliding in such a manner as to collapse, the implanting portion of the turbine blade is fitted into the implanting groove of the turbine disk. Therefore, it is not necessary to form the base end portion of the turbine blade in a straight line shape, and by forming the base end portion into a “<” shape along the curvature of the blade, as shown in FIGS. 12 (a) and (b). As shown by comparison, the distance between adjacent turbine blades, that is, the pitch P becomes smaller.

Further, the turbine disk and the turbine blade are formed of C / C composite, and a liquid resin which is burnt and carbonized such as pitch or phenol resin is provided between the implantation groove of the turbine disk and the implantation portion of the turbine blade. After impregnating, C
By performing the / C conversion treatment, the pitch is graphitized to firmly bond the two, and the turbine rotor becomes a pseudo-integral molded product.

In the method for integrally molding a C / C composite turbine rotor according to the present invention, a blade prepreg for molding a blade portion of the turbine rotor is laminated in a molding gap of a blade mold, and the prepreg is sandwiched. The blade mold in the state is attached to the outer peripheral part of the ring-shaped jig, and the prepreg forming the blade part is set in the mold in advance, and the blade shape is maintained at a predetermined position on the circumference. Since it is fixed to, the deformation is small, the molding is easy even if the pitch is fine and the blade shape is complicated.

Further, the end portion of the blade prepreg extending in the center direction from the blade die is multi-divided in the axial direction of the turbine rotor, and between the wheel prepregs when the main body wheel portion of the turbine rotor is laminated. The carbon fibers from the blade part are dispersed evenly in the wheel part without being cut in the middle by this, the integrity of the blade part and the wheel part is enhanced, and a rational fiber orientation is obtained. The strength will not be reduced.

[0014]

【Example】

Embodiment 1 FIG. 1 is a perspective view for explaining an embodiment of a split forming method for a turbine rotor according to the present invention. The turbine rotor 1 shown in the drawing is made of heat resistant steel specified as SUH660 in JIS G4312. Multiple turbine blades 2
And also made of SUH660 steel, with an outer diameter of 80 mm
Turbine disc 5 divided into three discs 3 and 4
The outer peripheral surfaces of the disks 3 and 4 are formed with the same number of planting grooves 3a and 4a as the turbine blades 2 for receiving the planting part 2b provided at the base end 2a of the turbine blade 2.

As shown in the figure, the turbine blade 2 has a curved blade shape, and the base end portion 2a and the implanting portion 2b of the turbine blade 2 are each shaped like a "k" according to the degree of curvature of the blade shape. It is shaped like a letter,
The implantation grooves 3a and 4a that receive the implantation portion 2b have different inclination angles with respect to the axial direction.

When assembling the above-mentioned respective components to form the turbine rotor 1, first, one end side of the implanting portion 2b of the turbine blade 2 is fitted into the implanting groove 3a of the one disk 3 and slid in the axial direction. All turbine blades 2 were mounted on the disk 3.

Next, the other disk 4 is slid from the other end side of the implanting portion 2b of the turbine blade 2, and each implanting portion 2b is inserted into each implanting groove 4a of the disk 4.
The discs 3 and 4 were connected to each other by screwing screws 6 and 6 together.

At this time, since the planted portion 2b is bent in a V shape, the two disks 3 and 4 are screwed to each other without fixing the turbine blade 2 to the disks 3 and 4. , 6 does not cause the turbine blade 2 to come off the turbine disk 5.

In this embodiment, 30 turbine blades 2 can be planted in the turbine disk 5, and up to 24 turbine blades of the same shape can be attached by the conventional turbine blade forming method. Compared with, it has become possible to greatly improve the efficiency of the turnbin.

Example 2 A turbine rotor having the same shape and size as in Example 1 was C /
After being formed by C composite, between the implantation groove of the turbine disk and the implantation portion of the turbine blade,
Pitch is impregnated into a gap formed at a joint portion such as between two discs, and then carbonized at about 500 to 900 ° C. and graphitized at about 2000 to 3000 ° C. to further increase density and strength. This pitch impregnation, carbonization treatment, and graphitization treatment were repeated to improve the temperature.

As a result, the pitch was graphitized and the members were firmly bonded to each other to form a pseudo-integral molded product, and a C / C composite turbine rotor having excellent lightness and heat resistance was obtained.

Embodiment 3 FIGS. 2 to 7 sequentially illustrate the steps of a method for integrally molding a C / C composite turbine rotor according to the present invention.

That is, first, as shown in FIG. 2, a blade prepreg 11 forming a blade portion of a turbine rotor is placed on a lower die 12a in the figure which constitutes one of the blade dies 12 divided into two. After stacking, the other mold 1
2b, while heating to about 80 ℃, the mold 12b
By tightening a bolt (not shown) through the bolt insertion hole 12c provided in the
1 so that the prepreg 11 has a predetermined shape.
It was sandwiched in a molding gap 12d formed between a and 12b. At this time, the blade prepreg 11
As shown in the drawing, the end portion of the blade is extended from the blade mold 12 toward the center of the turbine rotor. Further, as the blade prepreg 11,
A cloth prepreg made by weaving carbon fibers into a cloth is used, but in order to improve the radial strength of the blade, UD
(One direction) It is also possible to orient the prepreg in the radial direction, if necessary.

Next, the blade mold 12 with the blade prepreg 11 sandwiched therein is placed along the outer circumference of the ring-shaped jigs 13 and 14 in the molding gap 12d, and the mold 1
Positioning is performed on the ring-shaped jigs 13 and 14 by a knock pin that is inserted into a knock pin hole 12e of 2a, and is sequentially fixed as shown in FIG. 3 by a bolt (not shown) that is inserted through a bolt hole 12f provided in the mold 12a. did.

Then, as shown in FIG. 4, after all the molds 12 have been fixed along the ring-shaped jigs 13 and 14, they protrude from the blade mold 12 of the blade prepreg 11 toward the center. As shown in FIG. 5, cuts were made in the existing portions at a pitch of several mm, and the prepreg 11 was multi-divided in the axial direction of the turbine rotor.

Next, the lamination of the wheel prepreg that forms the main body wheel portion of the turbine rotor is started. At this time, as shown in FIGS. 6 (a), 6 (b) and 7, the blades are divided into multiple pieces. The extended ends of the prepregs 11 for wheels are dispersed and alternately sandwiched between the prepregs for wheels to be laminated.

That is, the wheel prepreg 15 is
A large-diameter cross prepreg 15a having a diameter substantially equal to the inner diameters of the ring-shaped jigs 13 and 14, and the blade prepreg 11 from the large-diameter cross prepreg 15a.
6 and a small-diameter cross prepreg 15b having a diameter reduced by the amount of extension from the mold 12, and the lowermost layer portion of the main body wheel portion of the turbine rotor shown in FIG.
As shown in (a), first, the large diameter cross prepreg 15
a is arranged, and a small-diameter cross prepreg 15b is provided at the center on the large-diameter cross prepreg 15a, and its fiber direction is 45 with respect to the fiber direction of the large-diameter cross prepreg 15a.
The small-diameter cross prepreg 15b is formed by partially laminating the blade prepreg 11 that has been laminated so as to intersect at an angle of 0 °, and has the outer periphery thereof cut and divided into multiple pieces as described above. 6A, and the large-diameter cross prepreg 15a was laminated on the fan-shaped cross prepreg 15a by spreading it in a fan shape as shown in FIG. 6B.

In this way, by alternately repeating the lamination of the layer composed of the blade prepreg 11 and the small-diameter cross prepreg 15b whose divided ends are expanded in a fan shape, and the layer composed of the large-diameter cross prepreg 15a, alternately. Figure 7
As shown in Fig. 1, the ring-shaped jig 1
Disk-shaped lower mold 1 having a diameter equal to the inner diameters of 3 and 14
The above prepregs were cured by heating to about 150 ° C. while applying pressure to 6 and the upper mold 17.

Depending on the strength required at this time, the UD prepreg may be oriented in the circumferential direction, or the prepreg made of a disk fabric may be used in place of the cross prepregs 15a and 15b, so that the circumference of the wheel portion can be reduced. It is also possible to improve the strength in the direction.

Then, the above-mentioned cured molding is subjected to 500 to 900.
Carbonization at a temperature of about ℃, and 2000-3000
Perform graphitization at a temperature in the range of ℃, pitch impregnation, carbonization (HIP treatment: pressure 1000
(kgf / cm ² , temperature 600 to 700 ° C.) and the graphitization treatment was repeated to increase the density of the molded body and obtain a turbine rotor having a specific gravity of 1.8.

The C / C composite turbine rotor integrally molded in this way is 1700 ° C. as it is in a reducing atmosphere rich in fuel such as hydrogen.
It can be used stably up to a point. Further, in an oxidizing atmosphere, by applying a SiC coating or the like, it becomes possible to use it stably up to about 1700 ° C. Embodiment 4 FIGS. 8 to 11 show another embodiment of the method for integrally forming a C / C composite turbine rotor according to the present invention, in which the blade mold 12 and the ring-shaped jigs 13 and 14 are used. A case where a rubber mold is used instead of the above will be described.

First, a metal master model 20 as shown in FIG. 8 was prepared, the master model 20 was placed in a cylindrical container having an inner diameter substantially equal to the outer diameter thereof, and silicone rubber was poured into the blade portion to be solidified. ..

After the silicone rubber has solidified, it is taken out from the cylindrical container and the master model 20 is taken out, so that the portion corresponding to the blade of the master model 20 becomes a molding gap 21a as shown in FIG. 9 (a). A molding die 21 for a blade was obtained. At this time, the molding die 21
The original elasticity of rubber allows the rubber to be easily separated from the master model 20.

Next, as shown in FIG. 9 (b), slits S are formed immediately above the molding gaps 21a of the rubber molding die 21, and the molding gaps 21 are formed when the prepregs are laminated.
A can be expanded.

Then, after laminating the blade prepregs 22 in the respective molding gaps 21a in the same manner as in the third embodiment,
Stored in a metal molding jig 23 as shown in FIG.
A ring-shaped lid 24 was put on and fixed with bolts 25. At this time, it goes without saying that the end portion of the blade prepreg 22 is in a state of being extended from the molding die 21 toward the center.

The procedure after this is basically the same as that of the third embodiment, and the blade prepreg 2
No. 2 of the molding die 21 is axially cut, and the extending end portions of the multi-divided blade prepreg 22 are dispersed to form a wheel prepreg 2
After laminating the wheel parts by alternately sandwiching them between 6 and 6, as shown in FIG. 11, while heating the disk-shaped lower mold 27 and the upper mold 28 while heating to about 150 ° C. The prepreg was hardened, and carbonized and graphitized under the same conditions as in Example 3 to obtain a turbine rotor having the same shape as the master model 20.

[0037]

As described above, in the turbine rotor split molding method according to the present invention, the turbine disk serving as the mounting base of the turbine blade is axially divided into two parts.
Due to the splitting, the mounting proximal end of the turbine blade can be formed into a “<” shape along the curvature of the blade portion, which allows the turbine blade to be closely implanted on the turbine disk. The efficiency of the turbine can be improved, and each of the members is formed of C / C composite, and after the molding, the joint is impregnated with pitch, for example, and subjected to C / C conversion treatment to graphitize the pitch. , Which has strong strength between each member, has excellent lightness and heat resistance, and has strength equivalent to that of an integrally molded product.
The excellent effect that a / C composite turbine rotor is obtained is brought about.

Further, in the method for integrally molding a C / C composite turbine rotor according to the present invention, a die having a blade prepreg sandwiched is attached to a ring-shaped jig to form a blade portion. Since the prepreg is fixed at a predetermined position on the circumference while maintaining the blade shape in the mold, there is little deformation during hot press molding, and it is easy to mold even when the blade shape is complicated and the blade pitch is small. Along with that, the end of the blade prepreg extended from the mold is divided into multiple parts in the axial direction so as to be dispersed between the wheel prepregs when the main body wheel part of the turbine rotor is laminated. Since the fibers are evenly distributed in the wheel without being cut, the blade and wheel are highly integrated, and stress Since no strength superior, has excellent effect that allows high-speed rotation is obtained.

Further, instead of the blade mold and the ring-shaped jig, by using a rubber-made molding die made from the master model, it becomes easy to stack the prepregs and remove the die after the press cure. Therefore, it becomes possible to form a turbine rotor having a blade with a smaller pitch and a more complicated shape.

By carrying out the C / C treatment in the present invention under a high pressure (1000 kg / cm ² ) (HIP treatment), the residual coal rate is increased to obtain a C / C composite having high density and high strength. You can

[Brief description of drawings]

FIG. 1 is an exploded perspective view for explaining an embodiment of a split molding method for a turbine rotor according to the present invention.

FIG. 2 is a perspective view showing a state in which a prepreg is set in a blade mold in an embodiment of a method for integrally molding a C / C composite turbine rotor according to the present invention.

FIG. 3 is a perspective view showing a state in which the mold set with the prepreg is fixed to a ring-shaped jig in the embodiment.

FIG. 4 is a plan view showing a state in which all the dies have been fixed to the ring-shaped jig in the embodiment.

FIG. 5 is a perspective view showing a state in which a blade prepreg extended from a mold is notched and is multi-divided in one embodiment.

6 (a) and 6 (b) are horizontal cross-sectional views showing a laminated state of an end portion of a blade prepreg and a wheel prepreg, which are multi-divided, at different axial positions.

FIG. 7 is a vertical cross-sectional view showing a laminated state of a main body wheel portion of a turbine rotor in the one embodiment.

FIG. 8 is a perspective view showing the shape of a master model in another embodiment of the method for integrally molding a C / C composite turbine rotor according to the present invention.

FIG. 9A is a perspective view showing a shape of a rubber molding die which is molded from a master model in the other embodiment, and FIG. 9B is an enlarged view of FIG. 9A.

FIG. 10 is a perspective view showing a state where a rubber molding die having blade prepregs laminated therein is housed in a molding jig in the other embodiment.

FIG. 11 is a vertical cross-sectional view showing a laminated state of a main body wheel portion of a turbine rotor in the other embodiment.

FIG. 12 is a schematic view for explaining the blade pitch reduction effect in the split forming method for a turbine rotor according to the present invention by comparing the present invention example of (a) and the conventional example of (b).

FIG. 13 is a perspective view illustrating a conventional split molding method for a turbine rotor.

14 (a) and 14 (b) are a plan view and a vertical sectional view, respectively, for explaining a conventional method for integrally molding a C / C composite turbine rotor.

FIG. 15 is a schematic cross-sectional view for explaining another conventional method for integrally forming a C / C composite turbine rotor.

[Explanation of symbols]

1 Turbine rotor 2 Turbine blade 2b Implantation part 3a, 4a Implantation groove 5 Turbine disk 11,22 Blade prepreg 12 Blade mold 12d, 21a Forming gap 13,14 Ring jig 15a, 26 Large diameter cross prepreg (for wheel) Prepreg) 15b Small diameter cross prepreg (Wheel prepreg) 20 Master model 21 Rubber molding die

Claims (4)

[Claims] 1. A method of molding a turbine rotor for implanting a turbine blade in a turbine disk by slidingly fitting an implant portion formed in a base end portion of the turbine blade into an implant groove provided in the turbine disk, The turbine disc is divided into two in the axial direction, and the divided turbine discs are slid from the respective different directions with respect to the turbine blade to fit the implantation portion of the turbine blade into the implantation groove of the turbine disc, and then to divide. A method of split-molding a turbine rotor, characterized in that said turbine disks are joined together. 2. The pitch between the implantation groove of the turbine disk and the implantation portion of the turbine blade in a state where the turbine disk and the turbine blade are formed of C / C composite and the turbine blade is implanted in the turbine disk. Alternatively, the method for split-molding a turbine rotor according to claim 1, wherein a C / C treatment is performed after impregnating the liquid resin of the carbon material raw material. 3. A ring-shaped jig for a plurality of blade molds, wherein a blade prepreg forming a blade portion of a turbine rotor is sandwiched in a molding gap with its end portion extending toward the center of the turbine rotor. After being arranged along the outer periphery of the blade forming prepreg, the extended end portion of the blade forming prepreg is multi-divided in the axial direction of the turbine rotor and is dispersed between the wheel prepregs forming the main body wheel portion of the turbine rotor. A method for integrally forming a C / C composite turbine rotor, comprising laminating the wheel prepregs. 4. The C / C composite turbine rotor integral molding according to claim 3, wherein a rubber molding die made from a master model is used instead of the blade die and the ring jig. Method.