JPH02274342A - Wing material processing method - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a wing, for example a blade for a generator.

The present invention relates to a method for processing formed materials such as nozzles, and in particular relates to a method for processing formed materials for blades with an asymmetrical blade cross-sectional shape, that is, the blade thickness on the steam outlet side is smaller than the blade thickness on the steam inlet side. It is something.

[Conventional technology] Traditionally, blades were machined by machining from a square piece of material or by die forging using a full die to form a material with a predetermined finishing allowance, and then machined to form the blade. It was intended to be completed.

Furthermore, in order to significantly reduce the number of man-hours required for machining after die forging, it is known that precision die forging is performed using a large-capacity precision screw press.

However, when machining from a square piece, the material yield is extremely poor and resources are wasted, and die forging using a full die not only makes the die expensive, but also reduces the lifespan of the die due to hot working. , the proportion of mold costs in processed products increases,
The cost of processed products is increasing. Furthermore, precision die forging requires excessive equipment costs, which are not easy to amortize.

As a solution to the above problems, JP-A-61-14
Publication No. 40 describes a method of obtaining a formed material by sequentially applying pressure in the longitudinal direction by a free forging method using a partial mold having a cross-sectional shape of a blade.

This will be explained using 5 drawings.

FIG. 9 is a perspective view showing a state in which a formed material is processed by the conventional free forging method.

In this figure, the blade processed portion 1' of the material (the cross-sectional shape is
(circular or rectangular) between the upper mold 3 for forming the abdomen and the lower mold 4 for forming the back, from the root part 1' f side to the tip part 1' e
While moving intermittently towards the side like an arrow,
This is a method of Jllit followed by pressure molding.

[Problems to be Solved by the Invention] The free forging method described above has a higher material yield than machining or die forging, and reduces equipment costs and
Although this method has the advantage of low mold cost, no consideration was given to processing a blade with an asymmetrical cross-sectional shape.

This will be explained using drawings.

FIG. 8 is a perspective view showing a formed material of a wing with an asymmetrical cross-sectional shape, which is a subject of the present invention.

In the figure, 1 is a wing part (details will be described later), and 2 is a dovetail part. The wing portion 1 has a tip portion 1a.

It has a root part 1f, an abdomen 1c, and a dorsal part 1d, and its wingspan is w,
'A height is the length of the H1 blade portion, and its cross-sectional shape is asymmetrical, with the blade thickness on the steam outlet side 1a being smaller than the blade thickness on the steam inlet side 1b.

When the conventional free forging method described above is applied to processing a material for a blade with an asymmetrical cross-sectional shape, the material flow on the steam outlet side where the blade thickness is small becomes larger than that on the inlet side. A problem arose in that the inner surface was curved so that the exit side was convex, making it impossible to obtain a high-precision molded material.

The present invention solves these problems and makes it possible to process a blade material having an asymmetrical cross-sectional shape with high precision by plastic working using a free forging method. The purpose of this invention is to provide a method for processing wing materials.

[Means for Solving the Problems] In order to solve the above-mentioned problems, there is provided a method for processing a wing material according to the present invention.

The wing section, which is a rectangular material having a wing section and a dovetail section, is plastically worked by a free forging method to form a wing section having a abdomen and a back section with a predetermined finishing allowance. In the material processing method, the plastic working consists of preforming using a flat punch and a V-lower mold, and finishing molding to finish the material into a material using an abdominal mold and a back mold. The flat punch has a pressing width in the longitudinal direction that is sufficiently shorter than the length of the wing portion, a pressing width in the width direction that is longer than the width of the blade processed portion, and a pressing surface that is flat. Yes.

The V-lower mold has a base line in which the inclination angle α' of one 1111j plane is parallel to a line connecting the steam inlet side end and the steam outlet side end of the cross section of the blade and is in contact with the back bottom surface; an angle α between the contact point and a line tangent to the back at the midpoint of the steam outlet side end, larger than an angle α formed with a line tangent to the other side surface, and an inclination angle β' of the other side surface; is smaller than the angle β between the base line and a line that touches the back at the midpoint between the contact point and the steam inlet side end, and the pressing width in the longitudinal direction is longer than the working width of the flat punch. The abdomen mold has a pressurizing width in the longitudinal direction that is sufficiently shorter than the length of the wing, and the shape in the width direction is approximately the same shape as the abdomen of the wing. The pressing width of the abdomen forming die is longer than the pressing width of the abdominal mold, and the shape in the width direction is approximately the same shape as the back of the wing portion, and the preforming is performed to form the rectangular material into the wing processed portion. While moving the rectangular material by an amount smaller than the pressing width in the longitudinal direction of the flat punch, with the pressurized surface of the blade parallel to the pressing surface of the flat punch, A preform is obtained by locally sequentially pressurizing the processed part, and the finishing forming involves rotating the preform by θ=α′−α from the steam inlet side to the steam outlet side. In this state, the preform was moved by an amount smaller than the pressure width in the longitudinal direction of the abdominal mold, and the wing processed portion was locally and sequentially pressed to obtain a preformed material. It is something.

More details are as follows.

The wing-processed portion of the rectangular material is formed into a wing by plastic working using the free forging method, which consists of the following two steps.

The first step is to press a flat pressurized surface.
/f, and the inclination angle α' of one side surface is α (= the base line parallel to the line connecting the steam inlet side end and the steam outlet side end of the cross section of the wing section and in contact with the bottom surface of the back part, and the contact point The inclination angle β' of the other side surface is larger than β (=the angle between the base line, the contact point, and the steam inlet end). (the angle formed with the line tangent to the back at the midpoint of
′ = θ), and the pressurizing width in the longitudinal direction is longer than the pressurizing width of the flat punch. This is a preforming process in which the blade is held in a state parallel to the pressure surface and sequentially pressurized to form a preformed product. and 1-凰戊子, whose shape in the width direction is almost the same as the back of the wing, and whose pressurized width in the longitudinal direction is longer than the pressurized width of the abdominal mold. The preform is rotated by 0 from the steam inlet side to the steam outlet side, and the wing processed parts are sequentially pressurized to finish forming the preform into a blank material.

[Operation] Finish forming is performed by tilting the preform obtained by preforming by θ (that is, by tilting the preform by θ so that the pressurized surface of the preform is higher on the steam inlet side). As a result, at the beginning of molding, the steam inlet side (thick side) of the preform is pressurized, and near the end of molding, the steam outlet side (thin side) is pressurized. Therefore, even if the blade has an asymmetrical true cross-sectional shape in which the blade thickness is different on the steam inlet and outlet sides, there is no in-plane curvature in the blade portion, and a high-precision molded material can be obtained.

[Example] The present invention will be described below by way of an example with reference to the drawings.

1 to 7 relate to one embodiment of the present invention. 1 is a front view showing the initial state of preforming, FIG. 2 is a perspective view showing details of the rectangular material in FIG. 1, and FIG. Figure 3 shows the entrance of the V-bottom type in Figure 1.

FIG. 4 is a front view showing the final stage of preforming, and FIGS. 5 to 7 are the initial state of final forming, respectively. It is a front view showing an intermediate stage and a final stage.

In this embodiment, a wing material 10 (FIG. 8) is formed from a rectangular material 11 (details will be described later) shown in FIG. 2. The rectangular material 11 consists of a wing processed part 7 and a tab teal part 2, and the wing processed part 7 has a tip part 7e and a root part 7.
f, its width is W+, its thickness is Hl, and its length is l.

First, the mold used for this molding (that is, preforming and final molding) will be explained.

A flat punch 9 and a V lower die 8 are used for preforming. The flat punch 9 has a pressing width in the longitudinal direction that is sufficiently shorter than the length of the blade (see Figure 8), and a pressing width in the width direction that is the width W' of the blade processed part (see Figure 2). longer than
The pressurizing surface is flat.

Further, the V-lower mold 8 is as shown in FIG.

The inclination angle of the outlet tapered part 8a on one side (the side forming the steam outlet side) is α', and the inclination angle of the artificial taper part 8b on the other side (the side forming the steam inlet side) is α'. β', and the magnitudes of these angles of inclination α and β′ satisfy the following relationship with respect to α and β (details will be described later) in FIG.

.・〉. ... (1)
β'kuβ ... (2) α-α=β-β
'(=θ)... (3) The above α is parallel to the line A connecting the end of the steam inlet side 1b and the end of the steam outlet side 1a of the cross section of the blade part, and is in contact with the bottom surface of the back part 1d. This is the angle formed by the base line B (this contact point is M) and the line C that touches the back portion 1d at the midpoint P between the contact point M and the end of the steam outlet side 1a.

Moreover, β is the base line B, the contact point M, and the steam inlet side 1.
This is the angle formed by the line that touches the back part 1d at the midpoint Q with the end of b. The pressing width of the V lower die 8 in the longitudinal direction is longer than the pressing width of the flat punch 9.

On the other hand, for finishing molding, an abdominal mold 3 and a back mold 5 are used (see FIG. 5). The abdomen mold 3 has a pressurizing width Wp in the longitudinal direction that is sufficiently shorter than the length of the wing portion, and a shape in the width direction that is approximately the same shape as the abdomen IC, which is obtained by transferring the abdomen in consideration of a predetermined finishing allowance. belongs to.

In addition, the back mold 5 is pressurized in the longitudinal direction (the width W is
The shape in one width direction, which is longer than the pressing width W of the abdominal mold 3, was transferred to the back part with consideration given to the predetermined finishing allowance. It has an entrance molding part 5b and an exit molding part 5a. It consists of a portion having almost the same shape as the back portion 1d, and (2) an entry guide portion 5b' and an exit guide portion 5a' which serve as guides.

A method for processing a wing material according to an embodiment of the present invention will be described using the mold configured as described above.

First, by a manipulator (not shown).

When the dovetail portion 2 of the rectangular material 11 is grasped and the NC control device [(not shown) is turned on, the blade processed portion 7 of the rectangular material 11 is pressed so that its pressurized surface is parallel to the pressurized surface of the flat punch 9. Using the V lower mold 8 and flat punch 9,
and is set at the first pressurizing position as shown in FIG. Here, flat punch 9
is lowered by a predetermined stroke amount δ, and pressurizes the blade processing portion 7. Next, the flat punch 9 rises, and at the same time,
By the manipulator, the rectangular material 11 is moved toward the manipulator by a predetermined feed pitch amount p1 smaller than the pressing width in the longitudinal direction of the flat punch 9, and the second pressing is performed. This operation is performed continuously, and the root portion 7
When pressure is applied from f to the tip 7e, the preforming is completed and a preformed product 6 is obtained. FIG. 4 shows the state, in which 6a is the exit processing section, 6a and 6a' are the corners thereof, 6b is the entrance processing section, and 6b' and 6b'' are the corners.

Next, as shown in FIG. 5, this preformed product 6 is rotated by the degree of θ (=α − α) by the manipulator and set in the back mold 5.

Then, in the same way as in the above-mentioned preforming, the abdominal molding die 3 moves the preformed product 6 from the root to the tip by a predetermined feed pitch amount p2 smaller than the pressure @wp.
Pressure molding is performed one by one while moving one by one. This molding proceeds from both corners 6b', 6b' of the inlet processed part 6b of the 5 preformed product 6 and the bottom corner 6a' of the outlet processed part 6a. At this time, the corner portion 6a' of the exit processing portion 6a is in a slightly floating state, but near the end of finishing punching, it comes into contact with the exit processing portion 5a of the back mold 5 and is press-formed. In this way, when the above-mentioned operation is repeated a predetermined number of times, finish forming is completed, and the raw material 10 having the desired wing portion 1 is formed.
is obtained.

A specific example will be shown.

For the dimensions of the wing portion 1 of the material 10, refer to FIG.
w=52m, wing height H=27mm, wing length L=220
mm (all with finishing allowance IIm). This wing section 1 is a straight wing with no twist, α=28°, β
=77° (see Figure 3).

The detailed shape will be omitted since it is complicated, but it has an asymmetrical shape in which the blade thickness is smaller on the steam outlet side 1a than on the steam inlet side 1b, and the material is 12Cr stainless steel.

Rectangular material 1 used to mold this material 10
1, with reference to FIG. 2, the dimensions of the blade processed portion 7 are 5 width W' = 40 m, thickness considering the expansion in the width direction and the decrease in wall thickness in the height direction during processing. H' = 33am,
Further, the length l was calculated from the condition that the volume was slightly larger than the volume of the back part 1 of the formed material 10, and the length l was set to 140 am.

Referring to FIG. 1, the flat punch 9 has a pressing width in the longitudinal direction of 15 m, a pressing width in the width direction of 65 m, and has a half-sided pressing surface.

The V lower mold 8 has α'=45°, p'=60'(α'
−α=β−β′=17°), and the pressure width in the longitudinal direction=
It is 30-.

Referring to FIG. 5, the abdominal mold 3 has a pressurizing width wp of 15 m in the longitudinal direction and a shape in the width direction that is almost the same as the abdominal IC.

The back mold 5 has a pressurizing width w=301 in the longitudinal direction, and its shape in the width direction includes a portion that is almost the same as the back portion 1d and a guide portion.

The processing was carried out under hot conditions (approximately 1000° C. at the start of processing and approximately 800° C. at the end).

First, in the preforming, the feed pitch amount P1=lO111
1, the number of passes (the number of repetitions of pressurization from the root to the tip) is 2, and the stroke amount for each time is L.
2m, 10m (total 22an).

By this preforming, the height H' of the wing processed portion 7 of the rectangular material 11 is reduced by 3 mm to 30 m, and the preformed product 6
was gotten.

For finishing forming, the feed pitch amount Pz”P□=10II
m, the number of passes is 3, and the stroke amount for each time is
They were set to 8 m, 6 nu, and -3 ms (total 17 ■), respectively. As a result, a formed material 10 having a wing portion 1 with a finish allowance II and excellent shape accuracy was obtained.

According to the embodiment described above, there are the following effects.

(2) In-plane sharpness caused by the asymmetry of the cross-sectional shape of the X portion can be suppressed, and a blade material with good accuracy can be obtained.

◎ Compared to cutting, it is possible to improve the material yield, and it is also advantageous in terms of equipment costs and mold costs compared to die forging using a full die.

In addition, in this example, the molds were placed at the top and bottom, and the - side (V-bottom mold) was fixed, but both molds may be moved at the same time, or the molds may be moved from side to side. The same effect can be obtained by placing them. The feeding method for rectangular materials does not have to be intermittent;
Continuous feeding may be used, but in that case, it is necessary to taper the processing surface of the mold on the longitudinal side of the material, that is, on the side where the material is inserted. Further, the feed pitch amount may change for each process or each pass.

Furthermore, in the case of a relatively short wing like in this example, it is sufficient to grasp only one end, but if the wing span is thick or the asymmetry of the true cross section is even greater, it may be difficult to prevent bending. Gripping at both ends is preferable.

[Effects of the Invention] As described in detail above, according to the present invention, by using a free forging method that requires low equipment costs and mold costs, in-plane bending in the wing portion can be suppressed, and the true cross-sectional shape can be made asymmetric. Wings can be processed with high precision. As a result, the material yield can be improved compared to a method using cutting, and it is also advantageous in terms of equipment costs and mold costs compared to die forging using a full die.

In short, through plastic working using the free forging method,
It is possible to provide a method for processing a wing material, which can process a wing material having an asymmetrical cross-sectional shape with high precision.

[Brief explanation of drawings]

1 to 7 are for explaining a method of processing a wing material according to an embodiment of the present invention, and FIG. 1 is a front view showing the initial state of preforming, and FIG. 2 is a front view showing the initial state of preforming. 1 is a perspective view showing details of the rectangular material in FIG. 1, and FIG. 3 is an entrance of the V-bottom mold in FIG. 1. FIG. 4 is a front view showing the final stage of preforming, and FIGS. 5 to 7 are the initial state of final forming, respectively. FIG. 8 is a front view showing an intermediate stage and a final stage; FIG. 8 is a perspective view showing a formed material of an airfoil with an asymmetrical cross-sectional shape, which is the subject of the present invention; FIG. , is a perspective view showing a state in which a raw material is being processed. 1... Wings, 1c... Abdomen, 1d... Back, 2.
... Dovetail part, ... abdomen mold, 5 ... back mold, 7 ... wing processing part, 8 ... V lower mold, 9 ...
Flat punch, 10... wing material, 11... rectangular material.

Claims (1)

[Scope of Claims] 1. A wing portion having an abdomen and a back having a predetermined finishing allowance by plastically working the wing processing portion of a rectangular material having a wing processing portion and a dovetail portion using a free forging method. In the method for processing a blank material for a wing, the plastic working is performed by preforming using a flat punch and a V-lower die, and forming the blank material using an abdominal die and a back die. The flat punch has a pressurizing width in the longitudinal direction that is sufficiently shorter than the length of the wing section, a pressurizing width in the width direction that is longer than the width of the wing processing section, and The pressure surface is flat, and the inclination angle α' of one side of the V-shaped lower mold is a line connecting the steam inlet side end and the steam outlet side end of the cross section of the blade. An angle α between a base line that is parallel and touches the bottom of the back and a line that touches the back at the midpoint between the contact point and the steam outlet side end.
, the inclination angle β' of the other side surface is smaller than the angle β between the base line and a line that touches the back at a midpoint between the contact point and the steam inlet side end, and the pressure is applied in the longitudinal direction. The width is longer than the pressing width of the flat punch, and the abdomen mold has a pressing width in the longitudinal direction that is sufficiently shorter than the length of the wing section, and a shape in the width direction that is approximately the same shape as the abdomen of the wing section. The back mold has a pressure width in the longitudinal direction that is longer than the pressure width of the abdomen mold, and a shape in the width direction that is almost the same as the back of the wing, and The forming is performed by applying pressure in the longitudinal direction of the flat punch with the rectangular material positioned so that the pressurized surface of the blade processed portion is parallel to the pressing surface of the flat punch. A preform is obtained by locally sequentially pressurizing the blade pressurizing part while moving an amount smaller than the pressure width, and in the finishing forming, the preform is exposed to steam from its steam inlet side. While rotating the preform at θ=α′−α toward the exit side, the blade processed portion is locally moved while moving the preform by an amount smaller than the press width in the longitudinal direction of the abdominal mold. A method for processing a wing material, characterized in that the material is obtained by sequentially pressurizing the material.