Turbine partition plate casting forming mold

Abstract

The utility model belongs to the field of steam turbines, and provides a steam turbine partition plate casting forming mold which comprises a first set of mold and a second set of mold. Wherein the first set of mold comprises a shell, an inner ring, blade outer ring movable blocks and inner ring movable blocks, the inner ring is connected to the shell and matched with the shell to form a first containing cavity, the outer ring movable blocks are sequentially arranged in the first containing cavity and abut against the inner side wall of the shell, and the inner ring movable blocks are sequentially arranged in the first containing cavity and abut against the inner ring; the two opposite sides of the blades are detachably connected to the outer ring movable block and the inner ring movable block correspondingly and can be supported by the outer ring movable block and the inner ring movable block so that the blades can be evenly arranged at intervals according to a preset arc-shaped path, the second set of mold comprises an upper mold and a lower mold which are detachably connected, and the upper mold is matched with the lower mold to form a second containing cavity; the sand core and the blade are used for being arranged in the second containing cavity to be matched with the upper die and the lower die to form a final cavity used for forming the target steam turbine partition plate.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of steam turbines, and particularly relates to a steam turbine diaphragm casting forming die. BACKGROUND

[0002] As an important component of a steam turbine, the performance of a steam turbine diaphragm directly affects the overall operation efficiency and reliability of the steam turbine.

[0003] In traditional casting methods, there is a method of jointly casting blades and other structures (such as a diaphragm body). However, due to various factors (such as temperature gradient, metal flow, etc.) in the casting process, it is often difficult to ensure that the quality of the blades meets the design requirements. In order to solve this problem, a method of first casting blades and then combining them with other parts (such as a diaphragm body) for casting has appeared in the prior art. Although this method improves the quality of the blades to some extent, since the blades need to be arranged at uniform intervals according to a predetermined arc-shaped path, a complex support structure is needed to ensure the position and stability of the blades during the casting process. This not only increases the complexity of the die, but also leads to a decrease in production efficiency and an increase in cost. Therefore, it is necessary to solve the above technical problems. SUMMARY

[0004] The purpose of the embodiments of the present application is to provide a steam turbine diaphragm casting forming die to solve the technical problem of low casting efficiency of the steam turbine diaphragm in the prior art.

[0005] To achieve the above-mentioned purpose, the technical solution adopted by the present application is to provide a steam turbine diaphragm casting forming die, comprising:

[0006] A first set of molds for forming a sand core, the sand core being used to position a plurality of blades at a predetermined attitude and interval, the first set of molds comprising a shell, an inner ring, a plurality of blades, and a plurality of outer ring movable blocks and a plurality of inner ring movable blocks arranged in pairs corresponding to the number of blades, the inner ring being connected to the shell and cooperating with the shell to form a first containing cavity with an open top, the outer ring movable blocks being arranged in the first containing cavity in sequence and abutting against the inner side wall of the shell, the inner ring movable blocks being arranged in the first containing cavity in sequence and abutting against the inner ring, opposite sides of the blades being detachably connected to the outer ring movable blocks and the inner ring movable blocks and being capable of being supported by the outer ring movable blocks and the inner ring movable blocks to be arranged at uniform intervals according to a predetermined arc-shaped path, all the blades, all the outer ring movable blocks, and all the inner ring movable blocks collectively forming an intermediate cavity for forming the sand core, the open top of the first containing cavity being provided with a predetermined size so that the sand core can be integrally removed from the first containing cavity after being formed;

[0007] The second set of molds comprises an upper mold and a lower mold which are detachably connected, the upper mold cooperates with the lower mold to form a second accommodating cavity, and a pouring gate which communicates with the second accommodating cavity is further arranged on the upper mold, and the sand core and the blade are arranged in the second accommodating cavity to cooperate with the upper mold and the lower mold to form a final mold cavity for forming a target steam turbine diaphragm.

[0008] Optionally, the first set of molds further comprises a positioning ring which is arranged at the bottom of the inner ring loose piece and is used to support the inner ring loose piece and one side surface of the blade to form a zigzag shape for positioning the inner ring loose piece and the blade.

[0009] Optionally, the first set of molds further comprises a guide rail which is arranged at the bottom of the outer ring loose piece and is used to support one side surface of the outer ring loose piece to form a step for cooperating with the inner side wall of the shell to form a sliding fit clamping for the outer ring loose piece.

[0010] When the inner ring loose piece and the positioning ring position the blade, the corresponding outer ring loose piece can be adaptively displaced relative to the guide rail along the extension direction of the guide rail.

[0011] Optionally, the first set of molds further comprises an outer compression strip and an inner compression strip.

[0012] The outer compression strip is pressed against the top of the outer ring loose piece, and the inner compression strip is pressed against the top of the inner ring loose piece.

[0013] Optionally, the first set of molds further comprises a baffle.

[0014] The end of the shell and the end of the inner ring are detachably connected to the baffle and cooperate with the baffle to form the first accommodating cavity, and the end of the outer ring loose piece, the end of the inner ring loose piece, the end of the positioning ring, the end of the guide rail, the end of the outer compression strip and the end of the inner compression strip are all abutted on the baffle.

[0015] Optionally, the first set of molds further comprises a stopper which is arranged in the first accommodating cavity and is abutted on the inner side wall of the baffle.

[0016] The stopper is abutted on the adjacent surfaces of the outer compression strip, the inner compression strip, the positioning ring, the guide rail, the outer ring loose piece at the end and the inner ring loose piece at the end for plugging the two ends of the intermediate mold cavity.

[0017] Optionally, the surface of the shell and the inner ring for forming the first accommodating cavity is arranged to be inclined so that the cross-sectional shape of the first accommodating cavity in the arrangement direction of the blade presents an inverted trapezoid shape with the large end facing the opening.

[0018] Optionally, the outer ring loose piece and the inner ring loose piece are respectively formed with an arc-shaped cavity for accommodating the blade, and the inner ring loose piece comprises a first inner loose piece and a second inner loose piece which abut and cooperate to form the arc-shaped cavity;

[0019] The opposite two side walls of the second inner loose piece for abutting with the first inner loose piece are arranged at an angle and gradually move away from each other in a direction towards the center of the inner ring, and the angle A is 6°-8°.

[0020] Optionally, the arc-shaped cavity is a through cavity with both ends open.

[0021] The arc-shaped cavity formed on the inner ring loose piece further reserves a hollow area which is not filled by the blade, and the hollow area is located between the blade and the inner ring.

[0022] Optionally, the blade is provided with a plurality of through holes.

[0023] The through holes are located on both sides of the intermediate cavity and are symmetrically arranged.

[0024] The steam turbine diaphragm casting forming mold provided by the application has the following beneficial effects: compared with the prior art, two sets of molds are arranged in the steam turbine diaphragm casting forming mold provided by the application, the blade is uniformly arranged in the first accommodating cavity formed by the shell and the inner ring through the support of the outer ring loose piece and the inner ring loose piece in the first set of molds and along a preset arc-shaped path after the blade is processed, the outer ring loose piece and the inner ring loose piece abut on the shell and the inner ring respectively, and the blade and the two loose pieces cooperate to form an intermediate cavity for forming a sand core. In this way, the sand core can be quickly formed by filling the intermediate cavity with sand. After the sand core is formed, the blade, the outer ring loose piece and the inner ring loose piece can be integrally demolded from the first accommodating cavity. At this time, the blade is arranged in the sand core in a predetermined arrangement manner, and the outer ring loose piece and the inner ring loose piece are detachably connected to the blade. Therefore, after the outer ring loose piece and the inner ring loose piece are removed from the blade, the blade and the formed sand core can be transferred into a second accommodating cavity formed by the cooperation of an upper mold and a lower mold in the second set of molds. In this way, the blade does not need to be provided with another support structure in the process of forming other parts of the steam turbine diaphragm, thereby greatly simplifying the complexity of the mold in the forming process of the steam turbine diaphragm and facilitating the significant improvement of the casting efficiency of the steam turbine diaphragm, which is much better than the prior art. BRIEF DESCRIPTION OF DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the application, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are only some embodiments of the application, and other drawings can be obtained by those skilled in the art without creative labor.

[0026] Figure 1 This is a schematic diagram of the overall structure of the first mold in the embodiments of this application;

[0027] Figure 2 This is a schematic diagram of a partial structure of the first mold in the embodiments of this application. Figure One ;

[0028] Figure 3 This is a partial structural cross-sectional view of the first mold in the embodiments of this application;

[0029] Figure 4 This is a schematic diagram of a partial structure of the first mold in the embodiments of this application. Figure Two ;

[0030] Figure 5 This is a schematic diagram of a partial structure of the first mold in the embodiments of this application. Figure Three ;

[0031] Figure 6 This is a schematic diagram of the overall structure of the blade in an embodiment of this application;

[0032] Figure 7 This is a schematic diagram of the connection structure between the blade and the sand core in the embodiments of this application. Figure One ;

[0033] Figure 8 This is a schematic diagram of the connection structure between the blade and the sand core in the embodiments of this application. Figure Two ;

[0034] Figure 9 This is a schematic diagram of the overall structure of the second mold in the embodiments of this application;

[0035] Figure 10 This is a schematic diagram of the overall casting structure of the target steam turbine diaphragm in the embodiments of this application.

[0036] The reference numerals in the figures are as follows: 101, shell; 102, inner ring; 103, blade; 104, outer ring block; 105, inner ring block; 106, first receiving cavity; 107, intermediate cavity; 108, positioning ring; 1081, first positioning surface; 1082, second positioning surface; 109, guide rail; 110, outer pressure strip; 111, inner pressure strip; 112, baffle; 113, stop block; 114, arc-shaped cavity; 115, hollow area; 131, through hole; 151, first inner block; 152, second inner block; 201, upper mold; 202, lower mold; 203, second receiving cavity; 204, gating and riser; 205, positioning ring groove; 1000, sand core; 1001, positioning ring platform; 2000, target turbine partition. Detailed Implementation

[0037] In order to make the technical problems, technical solutions and beneficial effects of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only intended to explain the present application and not to limit the present application.

[0038] It should be noted that when an element is referred to as being "fixed" or "disposed" on another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or indirectly connected to the other element.

[0039] It should be understood that the terms "length", "width", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the purpose of facilitating the description of the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0040] In addition, the terms "first", "second" are only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "multiple" is two or more, unless otherwise specifically limited.

[0041] Please refer to Figures 1 to 10 , a steam turbine diaphragm casting forming mold provided by the embodiments of the present application will be described. The steam turbine diaphragm casting forming mold includes a first set of molds and a second set of molds. Among them:

[0042] The first set of molds is used for forming the sand core 1000, the sand core 1000 is used for positioning a plurality of vanes 103 in a preset posture and interval, the first set of molds comprises a shell 101, an inner ring 102, a plurality of vanes 103, and a plurality of outer ring movable blocks 104 and a plurality of inner ring movable blocks 105 arranged in pairs corresponding to the number of vanes 103, the inner ring 102 is connected to the shell 101 and cooperates with the shell 101 to form a first containing cavity 106 with an open top, the outer ring movable blocks 104 are arranged in the first containing cavity 106 in sequence and abut against the inner side wall of the shell 101, the inner ring movable blocks 105 are arranged in the first containing cavity 106 in sequence and abut against the inner ring 102, opposite sides of the vane 103 are respectively detachably connected to the outer ring movable block 104 and the inner ring movable block 105 and can be supported by the outer ring movable block 104 and the inner ring movable block 105 to be arranged in a uniform interval according to a predetermined arc-shaped path, all the vanes 103, all the outer ring movable blocks 104 and all the inner ring movable blocks 105 jointly constitute a middle cavity 107 for forming the sand core 1000, and the top of the first containing cavity 106 is provided with a preset size so that the sand core 1000 can be integrally taken out of the first containing cavity 106 after being formed;

[0043] The second set of molds comprises an upper mold 201 and a lower mold 202 which are detachably connected, the upper mold 201 cooperates with the lower mold 202 to form a second containing cavity 203, and the upper mold 201 is further provided with a pouring riser 204 which is communicated with the second containing cavity 203, the sand core 1000 and the vane 103 are used for being arranged in the second containing cavity 203 to cooperate with the upper mold 201 and the lower mold 202 to form a final cavity for forming the target steam turbine diaphragm 2000.

[0044] According to the above structure provided in the embodiment, two sets of molds are arranged in the turbine diaphragm casting forming mold provided in the embodiment, and after the blade 103 is processed, the blade 103 can be supported by the outer ring movable block 104 and the inner ring movable block 105 in the first set of molds and arranged in the first accommodating cavity 106 formed by the shell 101 and the inner ring 102 in a preset arc-shaped path. Since the outer ring movable block 104 and the inner ring movable block 105 abut on the shell 101 and the inner ring 102 respectively and cooperate with the blade 103, the outer pressure strip 110, the inner pressure strip 111, the positioning ring 108 and the guide rail 109 to form an intermediate cavity 107 for forming the sand core 1000. In this way, the sand core 1000 can be quickly formed by filling the molding sand in the intermediate cavity 107. After the sand core 1000 is formed, the sand core 1000, the blade 103 and the outer ring movable block 104 and the inner ring movable block 105 can be demolded from the first accommodating cavity 106 as a whole. At this time, the blade 103 is fixedly arranged in the sand core 1000 in a predetermined arrangement manner. Since the outer ring movable block 104 and the inner ring movable block 105 are detachably connected to the blade 103, the outer ring movable block 104 and the inner ring movable block 105 can be removed from the blade 103. Therefore, the blade 103 and the formed sand core 1000 can be transferred to the second accommodating cavity 203 formed by the upper mold 201 and the lower mold 202 in the second set of molds as a whole. In this way, the blade 103 does not need to be provided with another support structure in the process of forming other parts of the turbine diaphragm, thereby greatly simplifying the complexity of the mold in the forming process of the turbine diaphragm and facilitating to significantly improve the casting efficiency of the turbine diaphragm, which is much better than the prior art.

[0045] In another embodiment of the present application, please refer to Figures 1 to 10The first set of molds further comprises a positioning ring 108 arranged at the bottom of the inner ring loose piece 105, which is used to support the inner ring loose piece 105 and the one side surface of the blade 103 to form a sawtooth shape for positioning the inner ring loose piece 105 and the blade 103. According to the above structure provided in the embodiment, each tooth shape of the sawtooth shape formed at the top of the positioning ring 108 comprises a first positioning surface 1081 and a second positioning surface 1082 connected, wherein the first positioning surface 1081 is coplanar with the axis line of the positioning ring 108, and the second positioning surface 1082 is concave and extends along the circumferential direction of the positioning ring 108 in an arc shape, which is adapted to at least one section of the back side of the blade 103. In this way, when assembling the first set of molds, the outer ring loose piece 104 at the end is first installed on the guide rail 109, then the blade 103 is placed on the corresponding second positioning surface 1082 and the longitudinal edge thereof is abutted on the first positioning surface 1081, and the end surface of the blade 103 is abutted on the vertical wall of the inner ring 102, at this time, the other end of the blade 103 is supported by the outer ring loose piece 104, then the second inner loose piece 152 is installed on the inner arc surface of the blade 103 and is abutted on the first positioning surface 1081, and then the first inner loose piece 151 is installed on the second inner loose piece 152 and is also abutted on the first positioning surface 1081. In this way, the installation of all the blades 103, the outer ring loose pieces 104 and the inner ring loose pieces 105 is quickly and accurately completed by sequentially operating from the head to the tail, which is beneficial to further improve the assembly efficiency of the turbine diaphragm casting forming mold in the embodiment and ensure the positioning accuracy of the blade 103. It can be understood that the outer ring loose pieces 104 and the inner ring loose pieces 105 at the head and the tail of the positioning ring 108 and the guide rail 109 are processed so that they are parallel to the baffle 112 after being installed, that is, the outer ring loose pieces 104 and the inner ring loose pieces 105 at the head and the tail of the positioning ring 108 and the guide rail 109 are only a part of the outer ring loose pieces 104 and the inner ring loose pieces 105 to facilitate the assembly of the first set of molds.

[0046] In another embodiment of the present application, please refer to Figures 1 to 10The first set of molds further comprises a guide rail 109 arranged on the bottom of the outer ring loose block 104, which is used to support one side surface of the outer ring loose block 104 to form a step to match the inner side wall of the shell 101 to form a sliding fit clamping for the outer ring loose block 104; when the inner ring loose block 105 and the positioning ring 108 position the blade 103, the corresponding outer ring loose block 104 can be adaptively displaced relative to the guide rail 109 along the extension direction of the guide rail 109. According to the above structure provided in the embodiment, the step formed on the guide rail 109 can improve the position stability of the outer ring loose block 104 during the forming of the sand core 1000 by clamping the outer ring loose block 104 with the shell 101. In addition, since the inner ring loose block 105 is accurately positioned by the sawtooth structure arranged on the positioning ring 108, when the inner ring loose block 105 positions the blade 103, the outer ring loose block 104 can be appropriately adaptively displaced along the guide direction of the guide rail 109 under the action of the blade 103. It can be understood that the size of the adaptive displacement is within the range permitted by the process; in this way, the outer ring loose block 104 which can slide relative to the guide rail 109 can also eliminate part of the machining error and better support the blade 103, which is conducive to further improving the assembly efficiency of the steam turbine diaphragm casting forming mold in the embodiment, avoiding additional additional stress on the blade 103, and effectively ensuring the precision of the blade 103.

[0047] It can be understood that the embodiment is a preferred embodiment, and the positioning of the guide rail 109 close to the inner side wall of the shell 101 and the positioning ring 108 close to the inner ring 102 means that the larger activity space on one side of the shell 101 is fully utilized, which is conducive to the smoother installation of the outer ring loose block 104 on the guide rail 109, and at the same time, when the blade 103 is positioned by the positioning ring 108, the outer ring loose block 104 can better adapt to the positioning position.

[0048] In another embodiment of the present application, please refer to Figures 1 to 10, the first set of molds further comprises an outer pressing strip 110 and an inner pressing strip 111; the outer pressing strip 110 is pressed against the top of the outer ring loose piece 104, and the inner pressing strip 111 is pressed against the top of the inner ring loose piece 105. According to the above structure provided in the embodiment, the outer pressing strip 110 pressed against the top of the outer ring loose piece 104 and the inner pressing strip 111 pressed against the top of the inner ring loose piece 105 can effectively improve the position stability of the outer ring loose piece 104 and the inner ring loose piece 105 during the forming of the sand core 1000, which is beneficial to further improve the casting efficiency of the steam turbine diaphragm casting forming mold in the embodiment. Here, the outer pressing strip 110 and the inner pressing strip 111 can be connected to the inner ring 102 and the shell 101 by fasteners, respectively, or an external pressure can be applied, such as a weight on the upper end surface of the outer pressing strip 110 and the inner pressing strip 111, so that the outer pressing strip 110 and the inner pressing strip 111 are pressed against the corresponding outer ring loose piece 104 and inner ring loose piece 105, or the outer pressing strip 110 and the inner pressing strip 111 can be pressed against the corresponding outer ring loose piece 104 and inner ring loose piece 105 by their own weight. The site conditions can be flexibly selected.

[0049] Here, the part of the middle cavity 107 between the outer pressing strip 110 and the inner pressing strip 111 and between the positioning ring 108 and the guide rail 109 is also used to form a positioning ring table 1001, so that the sand core 1000 can be precisely positioned in the second accommodating cavity 203 by cooperating the positioning ring table 1001 with the positioning ring groove 205 provided in the upper mold 201 and the lower mold 202 of the second mold.

[0050] In another embodiment of the present application, please refer to Figures 1 to 10 , the first set of molds further comprises a baffle 112; the end of the shell 101 and the end of the inner ring 102 are detachably connected to the baffle 112 and cooperate with the baffle 112 to form the first accommodating cavity 106, and the outer ring loose piece 104 located at the end, the inner ring loose piece 105 located at the end, the end of the positioning ring 108, the end of the guide rail 109, the end of the outer pressing strip 110 and the end of the inner pressing strip 111 all abut against the baffle 112. According to the above structure provided in the embodiment, the baffle 112 detachably connected to the shell 101 and the inner ring 102 can open both ends of the first accommodating cavity 106 by separating from the shell 101 and the inner ring 102, which can make it more convenient to arrange the outer ring loose piece 104, the inner ring loose piece 105 and the blade 103 in the first accommodating cavity 106, and is beneficial to further improve the assembly efficiency of the steam turbine diaphragm casting forming mold in the embodiment, and further improve the casting efficiency. It can be understood that in order to better abut against the outer ring loose piece 104 and the inner ring loose piece 105, the outer ring loose piece 104 and the inner ring loose piece 105 provided at the end can be flatly attached to the baffle 112 by machining corresponding sections, which is beneficial to better maintain the position stability of the outer ring loose piece 104 and the inner ring loose piece 105 during the forming of the sand core 1000.

[0051] In another embodiment of the present application, referring to Figures 1 to 10 , the first set of molds further comprises a stopper 113 arranged in the first accommodating cavity 106 and abutting against the inner sidewall of the baffle 112; the stopper 113 is in abutment with the adjacent surfaces of the outer compression strip 110, the inner compression strip 111, the positioning ring 108, the guide rail 109, the outer ring movable block 104 and the inner ring movable block 105 at both ends, so as to block the two ends of the intermediate cavity 107. According to the above structure provided in the embodiment, the stopper 113 arranged at the starting point and the ending point of the arc-shaped path formed by the positioning ring 108 and the guide rail 109 can be flexibly positioned according to the forming shape of the sand core 1000, which is beneficial to further improve the stability of the steam turbine diaphragm casting forming mold in the embodiment, and thus improve the forming quality of the sand core 1000.

[0052] In another embodiment of the present application, referring to Figures 1 to 10 , the surfaces of the shell 101 and the inner ring 102 for forming the first accommodating cavity 106 are arranged obliquely so that the cross-sectional shape of the first accommodating cavity 106 in the arrangement direction of the blades 103 presents an inverted trapezoidal shape with the large end facing the opening. According to the above structure provided in the embodiment, the cross-sectional shape of the first accommodating cavity 106 in the arrangement direction of the blades 103 is arranged as an inverted trapezoidal shape, which is beneficial to the demolding of the whole formed by the sand core 1000, the blades 103, the outer ring movable block 104 and the inner ring movable block 105. This is beneficial to further improve the sand core 1000 forming efficiency of the steam turbine diaphragm casting forming mold in the embodiment. It can be understood that in the embodiment provided with the positioning ring 108, the guide rail 109, the outer compression strip 110 and the inner compression strip 111, the first accommodating cavity 106 arranged as the above cross-sectional shape is also beneficial to the demolding of this part of structure, which will not be described here. In actual production, referring to Figure 3 , the sidewalls of the inner ring 102 and the shell 101 for forming the first accommodating cavity 106 can be arranged at an included angle B, preferably the included angle B is arranged at 3-5° to facilitate demolding. For the convenience of description, the included angle of 5° between the two is taken as an example for description in the embodiment.

[0053] In another embodiment of the present application, referring to Figures 1 to 10 , the outer ring movable block 104 and the inner ring movable block 105 respectively form arc-shaped cavities 114 for accommodating the blades 103, and the inner ring movable block 105 comprises a first inner movable block 151 and a second inner movable block 152 which are alternately abutted and cooperated to form the arc-shaped cavities 114; wherein the opposite sidewalls of the second inner movable block 152 abutting against the first inner movable block 151 are arranged at an angle and gradually move away from each other in the direction towards the center of the inner ring 102, and the angle is A, then A=6°-8°. For the convenience of description, referring to Figure 5In this embodiment, the second inner movable block 152 is used to form a 7° angle between the opposite two side walls abutting against the first inner movable block 151.

[0054] According to the above structure provided in this embodiment, the significance of dividing the inner movable block 105 into the first inner movable block 151 and the second inner movable block 152 in this embodiment is that, since the inner movable block 105 is also uniformly arranged according to the arc-shaped path when the blade 103 is assembled, and since the direction in which the inner movable block 105 is separated from the blade 103 after the sand core 1000 is formed is towards the center of the circle formed by the arc-shaped path arranged by the blade 103, it is not conducive for the inner movable block 105 to be set as a whole to be separated from the blade 103. After the inner movable block 105 is set as the first inner movable block 151 and the second inner movable block 152 which are alternately abutting, the second inner movable block 152 can be used to set an angle between the opposite two side walls abutting against the first inner movable block 151 and gradually move away from each other in the direction towards the center of the inner circle 102. In this way, the second inner movable block 152 sandwiched between two first inner movable blocks 151 can be easily taken out and separated from the blade 103 and the sand core 1000. After the second inner movable block 152 is separated from the blade 103, the first inner movable block 151 also has sufficient space to move and is easily taken out from the blade 103 and the sand core 1000. This is conducive to further improving the molding of the sand core 1000 of the turbine diaphragm casting forming mold in this embodiment, and further improving the casting efficiency. It should be noted that, since the side walls used for abutting between adjacent outer movable blocks 104 gradually move closer to each other in the direction towards the center of the arc-shaped path, after leaving the first accommodating cavity 106, the outer movable block 104 itself is easily taken out from the blade 103 on the side away from the center of the arc-shaped path, and thus it is not necessary to be divided into two parts.

[0055] In another embodiment of the present application, please refer to Figures 1 to 10, the arc-shaped cavity 114 is a through cavity with both ends open; the arc-shaped cavity 114 formed on the inner ring movable block 105 further has a hollow area 115 not filled by the blade 103, and the hollow area 115 is located between the blade 103 and the inner ring 102. According to the above structure provided in the embodiment, the hollow area 115 not filled by the blade 103 in the arc-shaped cavity 114 of the inner ring movable block 105 can facilitate the external tool to be clamped in the hollow area 115, so that the inner ring movable block 105 can be further conveniently removed from the blade 103, and the casting efficiency of the steam turbine diaphragm casting forming mold in the embodiment can be further improved. Here, it can be understood that the hollow area 115 is formed in the following manner: the inner side walls of the first inner movable block 151 and the second inner movable block 152 are arc-shaped structures with the same diameter as the side wall of the inner ring 102, the end surface of the blade 103 is longitudinally perpendicular to the arc-shaped cavity 114, and the blade 103 has a set width. When the lower edge end surface of the blade 103 abuts against the side wall of the inner ring 102, the end surface is equivalent to being tangent to the side wall of the inner ring 102. Thus, the part of the end surface not abutting against the side wall of the inner ring 102 is away from the side wall of the inner ring 102 in the tangential direction, so that the hollow area 115 not filled by the blade 103 is reserved in the arc-shaped cavity 114.

[0056] In another embodiment of the present application, please refer to Figures 1 to 10 The blade 103 is provided with a plurality of through holes 131; the through holes 131 are located on both sides of the middle cavity 107 and are symmetrically arranged. According to the above structure provided in the embodiment, the casting liquid can pass through the through holes 131 arranged on the blade 103 to make the blade 103 tightly combined with the other part structures of the target steam turbine diaphragm 2000 in the process of forming the other part structures of the target steam turbine diaphragm 2000 by the second mold. Thus, the forming quality of the steam turbine diaphragm casting forming mold in the embodiment can be improved.

[0057] It should be noted that the blade 103 in the embodiment is usually made of 06Cr13Al material (melting point between 1480-1530℃) with a higher melting point, and the other part structures of the target steam turbine diaphragm 2000 are made of nodular cast iron QT400-18 material (casting temperature at 1420℃) with a relatively lower melting point. Thus, the blade 103 can maintain good structural stability in the casting process of the other part structures of the target steam turbine diaphragm 2000. Of course, the steam turbine diaphragm can also be made of other materials by those skilled in the art, as long as the melting point of the blade 103 is higher than the casting temperature of the subsequent casting material, which will not be described here.

[0058] The above only describes the preferred embodiments of the present application and is not used to limit the present application. Any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A turbine diaphragm casting forming mold characterized by, The first set of molds is used for molding a sand core (1000) for positioning a plurality of vanes (103) at preset attitudes and intervals, and comprises a shell (101), an inner ring (102), and a plurality of outer ring loose blocks (104) and a plurality of inner ring loose blocks (105) arranged in pairs corresponding to the number of the vanes (103). The inner ring (102) is connected to the shell (101) and cooperates with the shell (101) to form a first containing cavity (106) with an open top. The outer ring loose blocks (104) are arranged in the first containing cavity (106) in sequence and abut against the inner side wall of the shell (101). The inner ring loose blocks (105) are arranged in the first containing cavity (106) in sequence and abut against the inner ring (102). The opposite sides of the vanes (103) are detachably connected to the outer ring loose blocks (104) and the inner ring loose blocks (105) and can be supported by the outer ring loose blocks (104) and the inner ring loose blocks (105) to be arranged in uniform intervals along a predetermined arc-shaped path. The vanes (103), the outer ring loose blocks (104), and the inner ring loose blocks (105) together form a middle cavity (107) for molding the sand core (1000). The top of the first containing cavity (106) is provided with a preset size so that the sand core (1000) can be integrally removed from the first containing cavity (106) after being molded. The second set of molds comprises an upper mold (201) and a lower mold (202) detachably connected. The upper mold (201) cooperates with the lower mold (202) to form a second containing cavity (203). The upper mold (201) is further provided with a pouring riser (204) communicating with the second containing cavity (203). The sand core (1000) and the vanes (103) are arranged in the second containing cavity (203) to form a final cavity for molding a target steam turbine diaphragm (2000) together with the upper mold (201) and the lower mold (202).

2. The steam turbine diaphragm casting forming mold according to claim 1, wherein: The first set of molds further comprises a positioning ring (108) arranged at the bottom of the inner ring loose blocks (105). The positioning ring (108) supports the inner ring loose blocks (105) and one side surface of the vanes (103) to form a sawtooth shape for positioning the inner ring loose blocks (105) and the vanes (103).

3. The steam turbine diaphragm casting forming mold according to claim 2, wherein: The first set of molds further comprises a guide rail (109) arranged at the bottom of the outer ring loose blocks (104). The guide rail (109) supports one side surface of the outer ring loose blocks (104) to form a step for slidingly fitting and clamping the outer ring loose blocks (104) with the inner side wall of the shell (101). ​ When the inner ring loose piece (105) and the positioning ring (108) position the blade (103), the corresponding outer ring loose piece (104) can be adaptively displaced relative to the guide rail (109) along the extension direction of the guide rail (109).

4. The steam turbine diaphragm casting forming mold according to claim 3, characterized in that: The first set of molds further comprises an outer pressure strip (110) and an inner pressure strip (111); The outer pressure strip (110) is pressed against the top of the outer ring loose piece (104), and the inner pressure strip (111) is pressed against the top of the inner ring loose piece (105).

5. The steam turbine diaphragm casting forming mold according to claim 4, characterized in that: The first set of molds further comprises a baffle (112); The end of the shell (101) and the end of the inner ring (102) are detachably connected to the baffle (112) and cooperate with the baffle (112) to form the first containing cavity (106), and the end of the outer ring loose piece (104), the end of the inner ring loose piece (105), the end of the positioning ring (108), the end of the guide rail (109), the end of the outer pressure strip (110), and the end of the inner pressure strip (111) are all abutted on the baffle (112).

6. The steam turbine diaphragm casting forming mold according to claim 5, characterized in that: The first set of molds further comprises a stop block (113) arranged in the first containing cavity (106) and abutting against the inner side wall of the baffle (112); The stop block (113) is abutted against the adjacent surfaces of the outer pressure strip (110), the inner pressure strip (111), the positioning ring (108), the guide rail (109), the end of the outer ring loose piece (104), and the inner ring loose piece (105) on both sides for plugging both ends of the middle cavity (107).

7. The steam turbine diaphragm casting forming mold according to any one of claims 1-6, characterized in that: The surfaces of the shell (101) and the inner ring (102) for forming the first containing cavity (106) are obliquely arranged so that the cross-sectional shape of the first containing cavity (106) in the arrangement direction of the blade (103) presents an inverted trapezoid shape with the large end facing the opening.

8. The steam turbine diaphragm casting forming mold according to claim 1, characterized in that: Arc-shaped cavities (114) for accommodating the blades (103) are formed on the outer ring loose piece (104) and the inner ring loose piece (105) respectively, and the inner ring loose piece (105) comprises a first inner loose piece (151) and a second inner loose piece (152) that alternately abut and cooperate to form the arc-shaped cavities (114); The opposite side walls of the second inner loose piece (152) for abutting against the first inner loose piece (151) are angularly arranged and gradually move away from each other in the direction towards the center of the inner ring (102), and the angle A is 6°-8°.

9. The steam turbine diaphragm casting forming mold according to claim 8, characterized in that: The arc-shaped cavity (114) is a through cavity with both ends open; The arc-shaped cavity (114) formed on the inner ring movable block (105) further reserves a hollow area (115) not filled by the vane (103), and the hollow area (115) is located between the vane (103) and the inner ring (102).

10. The turbine diaphragm cast forming mold according to claim 1, characterized in that: The vane (103) is provided with a plurality of through holes (131); The through holes (131) are located on both sides of the middle cavity (107) and are symmetrically arranged.

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