JP6466793B2 - Turbine component manufacturing method, turbine component, and turbine component manufacturing apparatus - Google Patents

Description

  Embodiments described herein relate generally to a turbine component manufacturing method, a turbine component, and a turbine component manufacturing apparatus.

  In a power plant such as thermal power generation, a turbine such as a gas turbine or a steam turbine is installed, and fluid energy of the working fluid is converted into rotational energy. For example, in the case of a steam turbine, the turbine rotor rotates by receiving the pressure of the steam from the moving blade. The rotational driving force of the turbine rotor is transmitted to the generator to generate power. The rotor blades are arranged in the circumferential direction on the turbine rotor to form a rotor blade cascade, and a plurality of the rotor blade cascades are provided apart from each other in the rotation axis direction.

  In general, thermal power plants tend to increase the temperature of steam flowing into a steam turbine in order to improve power generation efficiency. For this reason, the further improvement of the high temperature characteristic requested | required of the heat-resistant steel used for a steam turbine is desired. Therefore, many ferritic heat-resistant steels having excellent heat resistance and economy are used for the rotor blades.

  By the way, in recent years, studies for manufacturing turbine parts such as a moving blade of a steam turbine and a turbine rotor by applying a three-dimensional additive manufacturing technique are in progress. This is for the purpose of producing a turbine component having a complicated three-dimensional shape at low cost and high quality. In particular, the application of 3D additive manufacturing technology to the manufacture of moving blades having a hollow structure and functional materials organized is being studied. The potential for applying the technology is considered high. Three-dimensional additive manufacturing technology is roughly divided into a powder bed method and a deposition method. Since the powder bed method is generally better in terms of accuracy, it is preferable to adopt the powder bed method for a moving blade that requires a precise shape.

JP 2012-241670 A

  In general, in the three-dimensional additive manufacturing technique, it is possible to reduce the surface roughness of the additive manufacturing object and form a smooth surface by using fine raw material powder. However, when a fine raw material powder is used, the number of times of lamination tends to increase. In this case, the modeling speed decreases, and a lot of time can be spent on the layered modeling. For this reason, since the surface roughness and modeling speed of the layered object are greatly influenced by the particle size of the raw material powder, there is a strong trade-off relationship.

  For example, a portion that requires a small surface roughness in the moving blade is limited to a portion such as a flow path portion or a sliding portion that is disposed in the flow path of the working fluid. If the entire moving blade is manufactured using fine raw material powder in accordance with the small surface roughness partially required in this way, the molding speed is reduced, the manufacturing time is increased, and the manufacturing efficiency may be reduced.

  Problems to be solved by the present invention include a turbine component manufacturing method, a turbine component, and a turbine component manufacturing method capable of efficiently manufacturing a turbine component by shortening a manufacturing time by three-dimensional additive manufacturing of a turbine component including a portion having a small surface roughness. A turbine component manufacturing apparatus is provided.

  The turbine component manufacturing method according to the embodiment is a method of manufacturing a turbine component using a turbine component manufacturing apparatus. The turbine component manufacturing method includes a step of storing raw material powder in a powder tank of a turbine component manufacturing apparatus, a raw material powder stored in the powder tank, a first powder, and a second powder having a particle size smaller than that of the first powder. And a step of classifying it. In the turbine component manufacturing method, the first powder layer including the first powder is formed, and the formed first powder layer is irradiated with an energy beam to dissolve the first powder, thereby forming the first powder dissolved layer. Forming a second powder layer containing the second powder, irradiating the formed second powder layer with an energy beam to dissolve the second powder, and forming a second powder dissolved layer. ing. The turbine part is layered by repeatedly performing at least one of the step of forming the first powder-dissolved layer and the step of forming the second powder-dissolved layer a plurality of times. The thickness of the first powder layer formed in the step of forming the first powder-dissolved layer is thicker than the thickness of the second powder layer formed in the step of forming the second powder-dissolved layer.

  The turbine component according to the embodiment is a turbine component manufactured by the above-described turbine component manufacturing method. The turbine component has a first part portion formed by the first powder-dissolved layer and a surface roughness formed by the second powder-dissolved layer, integrated with the first part portion, and smaller than the surface roughness of the first part portion. And a second part portion having.

  Furthermore, the turbine component manufacturing apparatus according to the embodiment is a turbine component manufacturing apparatus for manufacturing a turbine component. The turbine component manufacturing apparatus includes a powder tank that stores raw material powder, a classification mechanism that classifies the raw material powder stored in the powder tank into a first powder and a second powder having a particle diameter smaller than that of the first powder. It is equipped with. When the first powder is supplied from the classification mechanism, the first powder layer containing the first powder is formed by the powder layer forming mechanism, and the second powder containing the second powder is supplied when the second powder is supplied from the classification mechanism. A powder layer is formed. When the first powder layer is formed by the beam irradiation mechanism, the first powder layer is irradiated with the energy beam to form the first powder dissolved layer, and when the second powder layer is formed, the second powder layer is formed. An energy beam is irradiated to form a second powder dissolved layer. The control unit controls the classification mechanism, the powder layer formation mechanism, and the beam irradiation mechanism so that at least one first powder dissolution layer and at least one second powder dissolution layer are laminated to form a turbine component. Is done. The control unit controls the powder layer forming mechanism so that the thickness of the first powder layer is larger than the thickness of the second powder layer.

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing time by the three-dimensional additive manufacturing of the turbine component containing a part with small surface roughness can be shortened, and a turbine component can be manufactured efficiently.

FIG. 1 is a cross-sectional structure diagram illustrating an example of a steam turbine according to an embodiment. FIG. 2 is a side view showing an example of the moving blade of FIG. FIG. 3 is a schematic configuration diagram of a turbine component manufacturing apparatus for manufacturing the rotor blade of FIG. 2. FIG. 4 is a schematic view showing the classification mechanism of FIG. FIG. 5 is a schematic diagram for explaining a part of a method of manufacturing the moving blade of FIG. 2 using the turbine component manufacturing apparatus of FIG. FIG. 6 is a schematic diagram for explaining a part of the method for manufacturing the rotor blade subsequent to FIG. 5.

  Hereinafter, a turbine component manufacturing method, a turbine component, and a turbine component manufacturing apparatus according to an embodiment of the present invention will be described with reference to the drawings. As used in this specification, terms such as “horizontal”, “identical”, etc. that specify shapes and geometric conditions as well as their degree, for example, have the same function without being bound by a strict meaning. The range that can be expected is included.

  Here, first, a steam turbine will be described with reference to FIG. 1 as an example of a turbine. FIG. 1 shows an example of a low pressure steam turbine with a relatively low steam pressure.

  As shown in FIG. 1, the steam turbine 1 includes a casing 2, a turbine rotor 3 provided rotatably in the casing 2, and a plurality of blade cascades 4 attached to the turbine rotor 3. . The moving blade cascade 4 is composed of a plurality of turbine moving blades 10 (see FIG. 2, hereinafter simply referred to as moving blades) 10 arranged at a predetermined interval in the circumferential direction. On the other hand, a plurality of stationary blade cascades 5 arranged alternately with the moving blade cascades 4 are attached to the casing 2. The stationary blade cascade 5 includes a plurality of stationary blades (nozzles) arranged at a predetermined interval in the circumferential direction. Each moving blade cascade 4 and a corresponding stationary blade cascade 5 constitute a turbine stage. Among the plurality of turbine stages, the turbine stage 6 on the highest pressure side (upstream side) is referred to as a first stage, and the turbine stage 7 on the lowest pressure side (downstream side) is referred to as a final stage.

  Connected to the casing 2 is a steam pipe 8 for supplying steam generated in a boiler or the like (not shown) as a working fluid to the turbine stage. The steam supplied through the steam pipe 8 enters the first stage 6, flows downstream through each turbine stage, and exits from the final stage 7. During this time, the rotor blade 10 receives the expansion work of the steam and the turbine rotor 3 rotates. As a result, power is generated in a generator (not shown) connected to the turbine rotor 3. The steam that has escaped from the final paragraph 7 is sent to a condenser (not shown) provided outside the casing 2 to generate condensed water, and the generated condensed water is supplied to the above-described boiler. The

  Next, the moving blade 10 as an example of the turbine component manufactured by the turbine component manufacturing method according to the present embodiment will be described in more detail with reference to FIG.

  As shown in FIG. 2, the moving blade 10 includes a moving blade main body 11 and an implanted portion 12 provided at one end of the moving blade main body 11. Of these, the rotor blade main body 11 is a portion having a blade shape that is disposed in the steam flow path and receives pressure from the steam. The implanted portion 12 is formed to be engageable with an implanted groove (not shown) provided in the rotor disk 3a (see FIG. 1) of the turbine rotor 3, and the implanted portion 12 engages with the implanted groove, The moving blade 10 is configured to be attached to the turbine rotor 3. The moving blade body 11 and the implanted portion 12 are joined and integrated with each other. In the present embodiment, the rotor blade main body 11 (second component portion) has a surface roughness smaller than the surface roughness of the implanted portion 12 (first component portion).

  Next, the turbine component manufacturing apparatus according to the present embodiment will be described with reference to FIGS. 3 and 4. The turbine component manufacturing apparatus is for manufacturing the moving blade 10 using the turbine component manufacturing method according to the present embodiment.

  As illustrated in FIG. 3, the turbine component manufacturing apparatus 20 includes a powder tank 21 that stores a raw material powder 80 (see FIG. 4), and a raw material powder 80 that is stored in the powder tank 21, as a first powder 81 and a second powder 82. And a powder layer that forms a first powder layer 83 (see FIG. 5) containing the first powder 81 and a second powder layer 85 (see FIG. 6) containing the second powder 82. Forming mechanism 40.

  As shown in FIG. 4, the classification mechanism 30 according to the present embodiment includes a raw material powder 80 stored in the powder tank 21, a first powder 81, and a second powder 82 having a smaller particle diameter than the first powder 81. It is configured to classify. A raw material powder 80 (for example, atomized powder) having a predetermined particle size range such as a normal distribution is stored in the powder tank 21, and the classification mechanism 30 divides the raw material powder 80 dropped from the powder tank 21 into particles. The powder is classified into a first powder 81 having a relatively large diameter and a second powder 82 having a relatively small particle diameter.

  More specifically, the classification mechanism 30 classifies the raw material powder 80 into a first powder 81 and a second powder 82, holds the first powder 81 and passes the second powder 82, and a sieve plate 31. The powder receiving plate 32 that holds the second powder 82 that has passed through the sieve plate 31 and the discharge portion 33 that discharges the first powder 81 and the second powder 82 separately. Among these, the sieve plate 31 and the powder receiving plate 32 are accommodated in the main body case 30a in a state of being attached horizontally.

  The sieve plate 31 includes a large number of holes, and the hole diameter of each hole is preferably a diameter within the particle size range of the raw material powder 80. As a result, the powder having a particle size larger than the hole diameter of the sieve plate 31 in the raw material powder 80 dropped from the powder tank 21 does not pass through the sieve plate 31 but remains on the sieve plate 31 as the first powder 81. On the other hand, the powder having a small particle size equal to or smaller than the pore size of the sieve plate 31 in the raw material powder 80 passes through the sieve plate 31 as the second powder 82 and falls. The dropped second powder 82 remains on the powder receiving plate 32 provided below the sieving plate 31. Note that the sieve plate 31 may be configured to be capable of applying vibrations in order to allow the second powder 82 to pass through quickly.

  In this way, the powder having a particle diameter larger than the hole diameter using the hole diameter of the sieve plate 31 as a threshold value remains on the sieve plate 31 as the first powder 81, and the powder having a smaller particle diameter equal to or smaller than the hole diameter is the first powder 81. It remains on the powder receiving plate 32 as two powders 82. Here, the raw material powder 80 has a predetermined particle size range as described above, and the first powder 81 and the second powder 82 classified by the sieve plate 31 also include powders having various particle sizes. . Therefore, there is a difference between the average particle size of the classified first powder 81 (here, for example, the average particle size that can be geometrically calculated from the particle size distribution) and the average particle size of the second powder 82, and this average The difference in particle size can produce a difference in surface roughness as described below.

  The first powder 81 retained on the sieve plate 31 is supplied to the discharge unit 33 through the first passage 34 extending from the main body case 30a. More specifically, the first powder 81 retained on the sieve plate 31 is pushed out from the sieve plate 31 to the first passage 34 by the first pushing portion 35. The first extruding portion 35 is configured to be reciprocally movable on the sieve plate 31 along the upper surface thereof (in the horizontal direction, in the left-right direction in FIG. 4), and when moving toward the first passage 34, The first powder 81 retained on the sieve plate 31 is pushed out into the first passage 34 and stored in the first passage 34. A first opening / closing valve 36 is provided in the first passage 34. 4 shows an example in which the first on-off valve 36 is a damper valve, the present invention is not limited to this. The first on-off valve 36 is opened when the first powder 81 stored in the first passage 34 is supplied to the discharge unit 33, and is closed when the supply of the first powder 81 to the discharge unit 33 is stopped.

  The second powder 82 fastened on the powder receiving plate 32 is supplied to the discharge part 33 through the second passage 37 extending from the main body case 30a. More specifically, the second powder 82 held on the powder receiving plate 32 is pushed out from the powder receiving plate 32 to the second passage 37 by the second pushing portion 38. The second extruding portion 38 is configured to be able to reciprocate on the powder receiving plate 32 along the upper surface thereof (in the horizontal direction, in the left-right direction in FIG. 4), and when moving toward the second passage 37. The second powder 82 held on the powder receiving plate 32 is pushed out into the second passage 37 and stored in the second passage 37. A second opening / closing valve 39 is provided in the second passage 37. 4 shows an example in which the second on-off valve 39 is a damper valve, the present invention is not limited to this. The second on-off valve 39 is opened when the second powder 82 stored in the second passage 37 is supplied to the discharge unit 33, and is closed when the supply of the second powder 82 to the discharge unit 33 is stopped.

  The first on-off valve 36 and the second on-off valve 39 are controlled by a control unit 70 (see FIG. 3), which will be described later, and either one is opened and the other is closed. That is, when supplying the 1st powder 81 to the dispenser 44 mentioned later, the 1st on-off valve 36 opens and the 2nd on-off valve 39 closes. On the other hand, when supplying the second powder 82 to the dispenser 44, the first on-off valve 36 is closed and the second on-off valve 39 is opened. In this manner, either one of the first powder 81 and the second powder 82 is supplied from the classification mechanism 30 to the dispenser 44.

  As shown in FIG. 3, the powder layer forming mechanism 40 according to the present embodiment includes a stage 41 on which a first powder layer 83 (see FIG. 5) and a second powder layer 85 (see FIG. 6) are formed, and a stage 41 And a stage drive unit 42 for lowering the position. Among these, the stage 41 is accommodated in the layered modeling part 43 for layered modeling of the rotor blade 10, and is configured to be moved up and down by the stage driving unit 42 in the layered modeled part 43. The stage driving unit 42 forms a first first powder-dissolved layer 84 or a new second powder-dissolved layer 84 (see FIG. 5) or a second powder-dissolved layer 86 (see FIG. 6). In order to form the powder dissolution layer 86, the stage 41 is configured to be lowered.

  The powder layer forming mechanism 40 further includes a dispenser 44 that supplies the first powder 81 or the second powder 82 onto the stage 41. The dispenser 44 forms a first powder layer 83 including the first powder 81 on the stage 41 when the first powder 81 is supplied from the discharge unit 33 of the classification mechanism 30, and the second powder from the discharge unit 33. When 82 is supplied, a second powder layer 85 including the second powder 82 is formed on the stage 41. The dispenser 44 is movable in the horizontal direction above the stage 41 by a dispenser driving unit (not shown), and supplies the first powder 81 or the second powder 82 onto the stage 41 while moving. The dispenser 44 can switch between supplying and stopping the supply of the first powder 81 or the second powder 82 on the stage 41. The first powder layer 83 or the second powder layer 85 formed on the stage 41 is flattened at a desired thickness by the leveling member 45 that can move in the horizontal direction, and the desired thickness is formed on the stage 41. The first powder layer 83 or the second powder layer 85 may be formed. Note that the description on the stage 41 is not limited to the case where powder is directly supplied on the stage 41 or a layer is directly formed. This is used as a concept including a case where a new powder is supplied or a new layer is formed on the layer.

  The turbine component manufacturing apparatus 20 further includes a beam irradiation mechanism 50 that irradiates a laser beam (energy beam). When the first powder layer 83 is formed on the stage 41, the beam irradiation mechanism 50 irradiates the first powder layer 83 with the laser beam to form the first powder dissolved layer 84, and the second powder on the stage 41. When the powder layer 85 is formed, the second powder layer 85 is formed by irradiating the second powder layer 85 with a laser beam. The beam irradiation mechanism 50 includes a beam generation device 51 that generates a laser beam and an irradiation head 52 that irradiates the laser beam generated by the beam generation device 51. Among these, the irradiation head 52 is configured to be movable in the horizontal direction above the stage 41 by a head driving unit (not shown). The irradiation head 52 irradiates a laser beam to a region corresponding to the cross-sectional shape of the moving blade 10 at a height position corresponding to the powder layers 83 and 85 based on the three-dimensional CAD data of the moving blade 10.

  The powder layer forming mechanism 40, the irradiation head 52, and the like are accommodated in a chamber 60 that can be adjusted to a predetermined atmosphere, for example, an inert gas or a vacuum atmosphere.

  The classification mechanism 30, the powder layer forming mechanism 40, and the beam irradiation mechanism 50 described above are controlled by the control unit 70.

  More specifically, the control unit 70 controls the extrusion units 35 and 38 of the classification mechanism 30, whereby the first powder 81 on the sieve plate 31 is pushed out to the first passage 34 and also on the powder receiving plate 32. The second powder 82 is pushed out into the second passage 37. In addition, the control unit 70 controls the on-off valves 36 and 39 of the classifying mechanism 30 to select the type of powder supplied to the dispenser 44.

  As the control unit 70 controls the stage driving unit 42 of the powder layer forming mechanism 40, the elevation of the stage 41 is controlled. At this time, the control unit 70 controls the stage driving unit 42 so that the thickness of the first powder layer 83 is larger than the thickness of the second powder layer 85. More specifically, the control unit 70 makes the descending amount of the stage 41 when forming the first powder layer 83 larger than the descending amount of the stage 41 when forming the second powder layer 85.

  The control unit 70 controls the dispenser 44 of the powder layer forming mechanism 40 to control the supply of powder from the dispenser 44 to the stage 41, and the dispenser drive unit is controlled to control the movement of the dispenser 44. Further, the control unit 70 controls the beam generator 51 to control the generation of the laser beam, and the head driving unit controls the movement of the irradiation head 52.

  In this way, the first powder 81 (or the second powder 82) is supplied onto the stage 41 to form the first powder layer 83 (or the second powder layer 85), and the first powder layer 83 (or the second powder layer 85). The powder layer 85) is irradiated with a laser beam to form the first powder-dissolved layer 84 (or the second powder-dissolved layer 86). Then, the first powder 81 or the second powder 82 is supplied onto the formed first powder dissolved layer 84 (or the second powder dissolved layer 86) in the same manner as described above, and the first powder dissolved layer 84 (or A second powder dissolution layer 86) is formed. In this manner, the first powder dissolved layer 84 (and / or the second powder dissolved layer 86) is repeatedly formed, and at least one first powder dissolved layer 84 and at least one second powder dissolved layer 86 are formed in the stage 41. The blades 10 are layered and stacked on top of each other.

  Next, the operation of the present embodiment having such a configuration will be described. Here, a method of manufacturing the moving blade 10 shown in FIG. 2 using the turbine component manufacturing apparatus 20 described above by the turbine component manufacturing method according to the present embodiment will be described. The operation of each part of the turbine component manufacturing apparatus 20 described below is performed by the control unit 70 controlling each part.

  First, the raw material powder 80 is stored in the powder tank 21 of the turbine component manufacturing apparatus 20.

  Subsequently, the raw material powder 80 stored in the powder tank 21 is classified into a first powder 81 and a second powder 82.

  More specifically, the raw material powder 80 falls from the powder tank 21 to the sieve plate 31 of the classification mechanism 30, and the first powder 81 having a particle diameter larger than the hole diameter of the sieve plate 31 is retained on the sieve plate 31. The first powder 81 held on the sieve plate 31 is pushed out to the first passage 34 by the first pushing portion 35. While the first opening / closing valve 36 is closed, the first powder 81 is stored in the first passage 34.

  On the other hand, the second powder 82 having a small particle size equal to or smaller than the pore diameter of the sieve plate 31 falls through the sieve plate 31 and is held on the powder receiving plate 32. The second powder 82 held on the powder receiving plate 32 is pushed out to the second passage 37 by the second pushing portion 38. While the second opening / closing valve 39 is closed, the second powder 82 is stored in the second passage 37.

  Such classification of the raw material powder 80 may be performed in parallel with each step of layered modeling of the moving blade 10 described later, for example, while the first on-off valve 36 and the second on-off valve 39 are closed. Good. In this case, the manufacturing time of the moving blade 10 can be shortened.

  Next, the implanted portion 12 (see FIG. 2) of the moving blade 10 is layered. Since the implanted portion 12 has a relatively large surface roughness, it is layered using the first powder 81 having a relatively large particle size. That is, the first powder layer 83 including the first powder 81 is formed on the stage 41, the first powder layer 83 is irradiated with a laser beam to dissolve the first powder 81, and the first powder dissolved layer 84. Is formed. A plurality of such first powder-dissolved layers 84 are formed and stacked, and the implanted portion 12 is layered. Below, the method of the layered modeling of the implantation part 12 is demonstrated in detail using FIG.

  First, as shown in FIG. 5A, the stage driving unit 42 (see FIG. 3) of the powder layer forming mechanism 40 is driven, and the stage 41 is positioned at a position lower than the upper end edge of the layered modeling unit 43 by a predetermined amount. It is done. The position of the stage 41 in this case is preferably a position that is lower than the upper edge of the layered modeling part 43 by an amount corresponding to the thickness of the first powder layer 83 described later. Here, the stage 41 is lowered by a descending amount larger than the descending amount of the stage 41 in the step shown in FIG.

  Subsequently, as shown in FIG. 5B, the first powder 81 classified by the classification mechanism 30 is supplied to the dispenser 44. In this case, the first on-off valve 36 is opened, and the first powder 81 stored in the first passage 34 is supplied to the discharge unit 33 and discharged from the discharge unit 33. The dispenser 44 is positioned below the discharge unit 33, receives the first powder 81 discharged from the discharge unit 33, and the first powder 81 is stored in the dispenser 44. At this time, the amount of the first powder 81 received by the dispenser 44 may be an amount for forming one first powder layer 83. When the first powder layer 83 is continuously laminated, The total amount that forms the plurality of first powder layers 83 to be stacked may be used.

  Next, as shown in FIG. 5C, when the first powder 81 is stored in the dispenser 44, the dispenser driving unit is driven to move the dispenser 44 in the horizontal direction, and the first powder 81 is moved to the stage 41. Supplied on top. After the first powder 81 is supplied onto the stage 41, the first powder 81 on the stage 41 is leveled by the leveling member 45 that moves in the horizontal direction, and the first powder layer 83 having a desired thickness is formed into the stage 41. Formed on top. The thickness of the formed first powder layer 83 is thicker than the thickness of the second powder layer 85 described later.

  Subsequently, as shown in FIG. 5D, the first powder layer 83 is irradiated with a laser beam from the irradiation head 52. In this case, the beam generator 51 generates a laser beam, and the head driving unit is driven to move the irradiation head 52 in the horizontal direction. As a result, the laser beam generated in the beam generator 51 is transmitted to the irradiation head 52 and irradiated onto the first powder layer 83 while the irradiation head 52 moves in the horizontal direction. The laser beam is irradiated based on the three-dimensional CAD data of the moving blade 10. That is, the cross-sectional shape of the moving blade 10 at the height corresponding to the first powder layer 83 is obtained from the three-dimensional CAD data, and the laser beam is scanned so that the cross-sectional shape is filled with the laser beam. In this way, the portion of the first powder layer 83 corresponding to the cross-sectional shape of the first powder 81 is dissolved, and the first powder dissolved layer 84 is formed on the stage 41. Here, since the first powder layer 83 is thicker than the second powder layer 85 as described above, the thickness of the formed first powder dissolved layer 84 is thicker than the thickness of the second powder dissolved layer 86 described later. Become.

  After the first powder dissolution layer 84 is formed, as shown in FIG. 5E, the stage driving unit 42 is driven and the stage 41 is lowered by a predetermined lowering amount. The descending amount in this case is an amount corresponding to the thickness of the new first powder layer 83 to be formed thereafter, but is the same as the descending amount of the stage 41 in the step shown in FIG. Is preferred.

  After the stage 41 is lowered, the first powder 81 is again supplied onto the stage 41 as described above, and the first powder-dissolved layer 84 already formed on the stage 41 as shown in FIG. A new first powder layer 83 is formed thereon. Thereafter, a laser beam is irradiated in the same manner as described above, and a portion of the first powder 81 corresponding to the cross-sectional shape of the rotor blade 10 at a height position corresponding to the new first powder layer 83 is melted and is renewed. A first powder dissolution layer 84 is formed. At this time, the previously formed first powder dissolution layer 84 is also at least partially dissolved by the laser beam applied to the new first powder layer 83. As a result, the new first powder-dissolved layer 84 is joined and integrated with the previously formed first powder-dissolved layer 84.

  By forming and laminating the first powder-dissolved layer 84 a plurality of times as described above, the implanted portion 12 of the moving blade 10 is layered as shown in FIG. In addition, by making the thickness of the first powder layer 83 thin and finely laminating, it is possible to obtain the implanted portion 12 having a precise shape conforming to the CAD data.

  Next, the moving blade body 11 (see FIG. 2) of the moving blade 10 is layered. Since the rotor blade body 11 has a relatively small surface roughness, it is layered using the second powder 82 having a relatively small particle size. That is, a second powder layer 85 including the second powder 82 is formed on the stage 41, and the formed second powder layer 85 is irradiated with a laser beam to dissolve the second powder 82, and the second powder dissolved layer 86. Is formed. A plurality of such second powder dissolution layers 86 are formed and stacked, and the rotor blade main body 11 is layered. Hereinafter, the layered manufacturing method of the rotor blade body 11 will be described in more detail with reference to FIG.

  First, as shown in FIG. 6A, the stage driving unit 42 is driven and the stage 41 is lowered by a predetermined lowering amount. The descending amount in this case is preferably an amount corresponding to the thickness of the second powder layer 85 described later. Here, the stage 41 is lowered by a lowering amount smaller than the lowering amount of the stage 41 in the step shown in FIG.

  Subsequently, as shown in FIG. 6B, the second powder 82 classified by the classification mechanism 30 is supplied to the dispenser 44. In this case, the second on-off valve 39 is opened, and the second powder 82 stored in the second passage 37 is supplied to the discharge unit 33 and discharged from the discharge unit 33. The dispenser 44 is positioned below the discharge unit 33, receives the second powder 82 discharged from the discharge unit 33, and the second powder 82 is stored in the dispenser 44. At this time, the amount of the second powder 82 received by the dispenser 44 may be an amount for forming one second powder layer 85 (described later), and the second powder layer 85 is continuously laminated as described later. In some cases, the total amount for forming a plurality of second powder layers 85 that are successively laminated may be used.

  Next, as shown in FIG. 6C, when the second powder 82 is stored in the dispenser 44, the dispenser driving unit is driven to move the dispenser 44 in the horizontal direction, and the second powder 82 is moved to the stage 41. Supplied on top. After the second powder 82 is supplied onto the stage 41, the second powder 82 on the stage 41 is leveled by the leveling member 45 that moves in the horizontal direction, and the second powder layer 85 having a desired thickness is formed into the stage 41. Formed on top. The thickness of the formed second powder layer 85 is thinner than the thickness of the first powder layer 83 described above.

  Subsequently, as shown in FIG. 6D, the second powder layer 85 is irradiated with a laser beam from the irradiation head 52 in the same manner as in the step shown in FIG. The laser beam is irradiated based on the three-dimensional CAD data of the moving blade 10. That is, the cross-sectional shape of the moving blade 10 at the height corresponding to the second powder layer 85 is obtained from the three-dimensional CAD data, and the laser beam is scanned so that the cross-sectional shape is filled with the laser beam. In this way, the portion of the second powder layer 85 corresponding to the cross-sectional shape of the second powder 82 is dissolved, and the second powder dissolved layer 86 is formed on the stage 41. Here, since the second powder layer 85 is thinner than the first powder layer 83 as described above, the thickness of the formed second powder dissolved layer 86 is larger than the thickness of the first powder dissolved layer 84 described above. Is also thinner.

  At this time, since the second powder 82 has a relatively small particle size, the second powder 82 can be totally dissolved by the irradiated laser beam so as not to leave its original shape. Therefore, the second powder dissolution layer 86 can be formed smoothly. At this time, the first powder dissolved layer 84 constituting the implanted portion 12 formed earlier is also at least partially dissolved by the laser beam applied to the second powder layer 85. Thus, the second powder dissolved layer 86 is joined and integrated with the first powder dissolved layer 84.

  After the second powder dissolution layer 86 is formed, as shown in FIG. 6E, the stage driving unit 42 is driven and the stage 41 is lowered by a predetermined lowering amount. The descending amount in this case is an amount corresponding to the thickness of the new second powder layer 85 to be formed thereafter, but it is the same as the descending amount of the stage 41 in the step shown in FIG. Is preferred.

  After the stage 41 is lowered, the second powder 82 is again supplied onto the stage 41 as described above, and as shown in FIG. 6F, the second powder dissolved layer 86 already formed on the stage 41 is obtained. A new second powder layer 85 is formed on top. Thereafter, in the same manner as described above, a laser beam is irradiated, and a portion of the second powder 82 corresponding to the cross-sectional shape of the rotor blade 10 at the height position corresponding to the new second powder layer 85 is melted and newly renewed. A second powder dissolution layer 86 is formed. At this time, the previously formed second powder dissolution layer 86 is also at least partially dissolved by the laser beam applied to the new second powder layer 85. Thus, the new second powder dissolved layer 86 is joined and integrated with the previously formed second powder dissolved layer 86.

  By repeatedly forming and laminating the second powder-dissolved layer 86 a plurality of times as described above, the rotor blade body 11 of the rotor blade 10 is layered as shown in FIG. In addition, by thinning and finely laminating the thickness of the second powder layer 85, it is possible to obtain the rotor blade body 11 having a precise shape conforming to the CAD data.

  When the layered modeling of the rotor blade main body 11 is completed, the rotor blade 10 shown in FIG. 2 having the implanted portion 12 and the rotor blade main body 11 joined and integrated with each other is obtained. Of the obtained moving blade 10, the moving blade body 11 is layered and formed using the second powder 82 having a relatively small particle size. As a result, the surface roughness of the rotor blade body 11 which is a portion formed by the second powder dissolution layer 86 is smaller than the surface roughness of the implanted portion 12 which is a portion formed by the first powder dissolution layer 84. ing.

  Thereafter, the shape of the rotor blade 10 is completed by adjusting the shape by grinding or polishing such as grinder processing, and then performing solution heat treatment, surface coating treatment as necessary, and aging heat treatment. However, since the surface roughness of the rotor blade body 11 is small as described above, the amount of grinding and polishing work can be reduced (may be omitted in some cases). Moreover, since the surface roughness of the rotor blade main body 11 can be reduced, the rotor blade main body 11 capable of improving the power generation efficiency can be easily obtained.

  As described above, according to the present embodiment, a plurality of first powder dissolution layers 84 formed by dissolving the first powder 81 are stacked, and the implanted portion 12 of the moving blade 10 is layered and formed, rather than the first powder 81. A plurality of second powder-dissolved layers 86 formed by dissolving the second powder 82 having a small particle size are stacked, and the rotor blade body 11 of the rotor blade 10 is layered. The thickness of the first powder layer 83 including the first powder 81 is thicker than the thickness of the second powder layer 85 including the second powder 82. As a result, for the rotor blade body 11 that requires a small surface roughness, the second powder 82 having a small particle size is used to reduce the surface roughness of the rotor blade body 11, and the implanted portion that does not require a small surface roughness. 12, the first powder 81 having a large particle size can be used to increase the thickness of the first powder layer 83 to increase the modeling speed. For this reason, the manufacturing time by the three-dimensional additive manufacturing of the moving blade 10 including the moving blade main body 11 having a small surface roughness can be shortened, and the moving blade 10 can be manufactured efficiently.

  Further, according to the present embodiment, the raw material powder 80 stored in the powder tank 21 of the turbine component manufacturing apparatus 20 is classified by the classification mechanism 30. This makes it unnecessary to prepare two tanks for separately storing two types of powders (first powder 81 and second powder 82) having different particle sizes. For this reason, the enlargement of the turbine component manufacturing apparatus 20 can be suppressed, and economical rationality can be ensured.

  Moreover, according to this Embodiment, the moving blade 10 can be laminate-molded by a powder bed system. Thereby, the shape accuracy of the rotor blade 10 to be layered can be improved. Further, the lowering amount of the stage 41 when the first powder layer 83 is formed is larger than the lowering amount of the stage 41 when the second powder layer 85 is formed, so that the thickness of the first powder layer 83 is increased. The thickness can be made thicker than the thickness of the second powder layer 85 easily.

  In the present embodiment described above, the intensity of the laser beam applied to the second powder layer 85 when the second powder dissolved layer 86 is formed (see FIGS. 6D and 6F) is When forming the powder dissolution layer 84 (see FIGS. 5D and 5F), the intensity of the laser beam applied to the first powder layer 83 may be made larger. In this case, the second powder 82 can be more reliably dissolved so that the original shape of the second powder 82 does not remain, and the second powder-dissolved layer 86 can be further smoothed. For this reason, the surface roughness of the rotor blade main body 11 on which the second powder dissolution layer 86 is laminated can be further reduced.

  In the above-described embodiment, the classification mechanism 30 includes one sieve plate 31 and a powder receiving plate 32, and the raw powder 80 is classified into the first powder 81 and the second powder 82. Explained. However, the present invention is not limited to this, and the classification mechanism 30 may have two or more sieve plates having different hole diameters so that the raw material powder 80 is classified into three or more types of particle diameters. . In this case, the surface roughness required by the design specifications in each part of the moving blade 10 can be realized more faithfully. Moreover, the part which makes surface roughness smaller than a request | requirement can be reduced, and modeling speed can be increased.

  Moreover, in this Embodiment mentioned above, the example in which all the powder which passed the sieve plate 31 of the classification mechanism 30 was fastened by the powder receiving plate 32, and was used as the 2nd powder 82 was demonstrated. However, the present invention is not limited to this, and instead of the powder receiving plate 32, another sieving plate having a smaller hole diameter than the sieving plate 31 may be used. In this case, the minimum particle size of the second powder 82 can be defined.

  In the above-described embodiment, it is preferable that the sieve plate 31 of the classification mechanism 30 can be replaced with the sieve plate 31 having a different hole diameter. In this case, the threshold value between the particle size of the first powder 81 and the particle size of the second powder 82 can be easily changed. That is, as described above, the raw material powder 80 generally includes powders having various particle sizes within a predetermined particle size range, and the maximum particle size of the second powder 82 is determined according to the particle size distribution. By setting the value, the yield of the raw material powder 80 can be improved, and the raw material powder 80 can be used effectively.

  Moreover, in this Embodiment mentioned above, the case where the moving blade 10 was laminate-molded by the powder bed system was demonstrated. However, the present invention is not limited to this, and the rotor blades 10 may be layered by a deposit method.

  Moreover, in this Embodiment mentioned above, the several 1st powder melt | dissolution layer 84 using the 1st powder 81 is laminated | stacked repeatedly, the implantation part 12 is layered, and the 2nd using the 2nd powder 82. The example in which the powder melt layer 86 is repeatedly laminated to laminate the moving blade main body 11 has been described. However, the present invention is not limited to this, and the number of laminations of the first powder-dissolved layer 84 is not limited to a plurality as long as it conforms to design specifications, and may be at least once. Similarly, the number of times the second powder dissolution layer 86 is stacked is not limited to a plurality, and may be at least once. In addition, the stacking order of the first powder-dissolved layer 84 and the second powder-dissolved layer 86 can be set arbitrarily according to the design specifications. The first powder dissolved layer 84 and the second powder dissolved layer 86 may be laminated so as to be smaller.

  In the above-described embodiment, an example in which a laser beam is used as an energy beam has been described. However, the present invention is not limited to this, and an electron beam may be used instead of the laser beam. In this case, it is preferable to scan the electron beam by deflecting an electron beam irradiated from an electron gun (not shown) by an electromagnetic coil instead of the irradiation head 52.

  Furthermore, in this Embodiment mentioned above, the example which laminate-models the moving blade 10 as an example of turbine components was demonstrated. However, the present invention is not limited to this, and other turbine parts such as the turbine rotor 3 (see FIG. 1) other than the rotor blade 10 can be layered. Moreover, although the low pressure steam turbine was demonstrated as an example of a turbine, arbitrary turbine components, such as a high pressure steam turbine and a gas turbine, can be layered and modeled.

  According to the embodiment described above, it is possible to reduce the manufacturing time by three-dimensional additive manufacturing of a turbine component including a portion having a small surface roughness, and to efficiently manufacture the turbine component.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

  Here, it was confirmed that the surface roughness of the portion where the second powder having a small particle size was dissolved was smaller than the surface roughness of the portion where the first powder having a large particle size was dissolved.

  Specifically, additive manufacturing is performed using a first powder and a second powder made of high chromium heat-resistant steel (10% Cr-1% W-2% Co steel) each applied to a moving blade of a steam turbine. went. The particle size of the first powder was −90 / + 45 μm (45 μm to 90 μm), and the particle size of the second powder was −32 / + 16 μm (16 μm to 32 μm). 50 kg of each of the first powder and the second powder was prepared.

  First, layered modeling was performed using the first powder, and a layered model having a square planar shape with a side of 10 mm and a thickness of 10 mm was obtained. Then, on the said layered model, it laminate-modeled using the 2nd powder, and the layered model of the 2nd powder which has the thickness of 10 mm with the same planar shape was laminated | stacked. The additive manufacturing using the first powder and the additive manufacturing using the second powder were performed under the same conditions except that the particle size of the powder was different.

  The surface roughness of the obtained layered product was measured. A laser microscope was used for the measurement. According to the measurement results, the surface roughness of the portion formed by the first powder was 50 s in terms of arithmetic average roughness (JIS B 0601-2001). On the other hand, the surface roughness of the portion formed by the second powder was 12.5 s in terms of arithmetic average roughness. Thus, it was confirmed that the surface roughness of the portion formed by the layered modeling with the second powder having a small particle size was smaller than the surface roughness of the portion formed by the layered modeling with the first powder having the large particle size.

DESCRIPTION OF SYMBOLS 1 Steam turbine 10 Moving blade 11 Moving blade main body 12 Implantation part 20 Turbine component manufacturing apparatus 21 Powder tank 30 Classification mechanism 40 Powder layer formation mechanism 41 Stage 42 Stage drive part 50 Beam irradiation mechanism 70 Control part 80 Raw material powder 81 1st powder 82 Second powder 83 First powder layer 84 First powder dissolved layer 85 Second powder layer 86 Second powder dissolved layer

Claims (9)

A turbine component manufacturing method for manufacturing a turbine component using a turbine component manufacturing apparatus,
Storing raw material powder in a powder tank of the turbine component manufacturing apparatus;
Classifying the raw material powder stored in the powder tank into a first powder and a second powder having a particle size smaller than the first powder;
Forming a first powder layer containing the first powder, irradiating the formed first powder layer with an energy beam to dissolve the first powder, and forming a first powder dissolved layer;
Forming a second powder layer containing the second powder, irradiating the formed second powder layer with an energy beam to dissolve the second powder, and forming a second powder dissolved layer. ,
By repeatedly performing at least one of the step of forming the first powder-dissolved layer and the step of forming the second powder-dissolved layer a plurality of times, the turbine component is layered,
The thickness of the first powder layer formed in the step of forming the first powder dissolved layer is thicker than the thickness of the second powder layer formed in the step of forming the second powder dissolved layer. A turbine component manufacturing method characterized by the above.   The intensity of the energy beam applied to the second powder layer in the step of forming the second powder dissolved layer is the intensity of the energy beam applied to the first powder layer in the step of forming the first powder dissolved layer. The method of manufacturing a turbine component according to claim 1, wherein the turbine component manufacturing method is larger than a value. The first powder dissolved layer and the second powder dissolved layer are formed on a stage,
After forming the first powder-dissolved layer or the second powder-dissolved layer, the stage is lowered, and thereafter, the new first powder-dissolved layer or the new second powder-dissolved layer is formed. The method of manufacturing a turbine component according to claim 1 or 2, wherein:   4. The turbine component manufacturing according to claim 3, wherein the lowering amount of the stage when forming the first powder layer is larger than the lowering amount of the stage when forming the second powder layer. 5. Method. A turbine component manufactured by the turbine component manufacturing method according to any one of claims 1 to 4,
A first part portion formed by the first powder-dissolved layer;
And a second component portion formed by the second powder-dissolved layer, integrated with the first component portion, and having a surface roughness smaller than the surface roughness of the first component portion. parts. A turbine component manufacturing apparatus for manufacturing a turbine component,
A powder tank for storing raw material powder;
A classification mechanism for classifying the raw material powder stored in the powder tank into a first powder and a second powder having a particle size smaller than the first powder;
A first powder layer containing the first powder is formed when the first powder is supplied from the classification mechanism, and a second powder containing the second powder is supplied when the second powder is supplied from the classification mechanism. A powder layer forming mechanism for forming a powder layer;
When the first powder layer is formed, the first powder layer is irradiated with an energy beam to form a first powder dissolved layer, and when the second powder layer is formed, energy is applied to the second powder layer. A beam irradiation mechanism for irradiating a beam to form a second powder-dissolved layer;
The classification mechanism, the powder layer forming mechanism, and the beam irradiation mechanism are arranged so that at least one of the first powder-dissolved layer and at least one second powder-dissolved layer are stacked to laminate the turbine component. A control unit for controlling,
The said control part controls the said powder layer formation mechanism so that the thickness of the said 1st powder layer may be thicker than the thickness of the said 2nd powder layer, The turbine components manufacturing apparatus characterized by the above-mentioned.   The control unit controls the beam irradiation mechanism so that the intensity of the energy beam applied to the second powder layer is larger than the intensity of the energy beam applied to the first powder layer. The turbine component manufacturing apparatus according to claim 6.   The powder layer forming mechanism includes: a stage on which the first powder dissolved layer and the second powder dissolved layer are formed; and the first powder dissolved layer or the second powder dissolved layer is formed, and then the first first The turbine component manufacturing apparatus according to claim 6, further comprising: a stage driving unit that lowers the stage in order to form a powder dissolved layer or a new second powder dissolved layer.   The control unit controls the stage driving unit so that the lowering amount of the stage when forming the first powder layer is larger than the lowering amount of the stage when forming the second powder layer. The turbine component manufacturing apparatus according to claim 8, wherein:

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