Direct chilling block and fixing system of wind power bearing seat

Abstract

A direct chilling block and a fixing system of a wind power bearing seat structurally comprise a chilling block body, the chilling block body is at least provided with a first surface and a second surface which are oppositely arranged, the chilling block body is buried in a sand core, the first surface is located in the sand core, a lifting lug is arranged on the first surface, and the second surface is located in the sand core. The second surface is flush with one outer side surface of the sand core embedded in the second surface; the second surface is used for being in direct contact with a wind power bearing seat casting; according to the scheme, the sand filling device has the advantages that the direct chillers can be effectively fixed, displacement is not prone to occurring in the sand filling process, the number of the chillers is small, the labor intensity of placing the chillers is small, and the production efficiency can be effectively improved.

Description

Technical Field

[0001] The present application relates to the field of casting technology for castings used in the field of wind energy, and particularly to a direct chill and fixing system for a wind power bearing seat. Background Art

[0002] With the rapid development of the wind power industry, the demand for ductile iron fittings for wind power has increased rapidly, and the ductile iron used for wind power has developed rapidly. Due to its low cost and high strength and toughness, ductile iron has been widely used at home and abroad. However, compared with ordinary ductile iron, higher quality and performance requirements are imposed on wind power castings because the working environment of wind turbines is harsh and maintenance is difficult. Therefore, higher quality and service performance requirements are imposed on wind power castings. As shown in the appendix Figure 1 is a large ductile iron wind power bearing seat (XB bearing seat). The casting product includes a wind power bearing seat casting a. The casting body a includes a middle cylindrical-like structure with a hollow central hole, and vertical parts are arranged on both radial sides of the cylindrical-like structure; there is a body nesting part a1 between the cylindrical-like structure and the vertical parts; the overall blank weight of this casting is 4,800 Kg, the pouring weight is 5,700 Kg, the material is ductile iron EN-GJS-400-18LT, the external dimensions are 3,585 mm × 2,280 mm × 430 mm, the maximum wall thickness is 400 mm, and the minimum wall thickness is 60 mm. For the casting product, there are key parts (vertical part a3 not shown in the figure) extending vertically on both sides, and in the middle is a cylindrical-like structure with a central hole. No casting defects such as slag inclusions, shrinkage cavities, and shrinkage porosity are allowed in this key part (vertical part a3), and the requirements are extremely high. In addition, sampling rods are inserted into the 320-mm-thick key part (vertical part a3) of the casting to test the mechanical properties (yield strength, tensile strength, elongation (elongation rate), impact performance, hardness) and metallography. The mechanical properties should meet the corresponding values in EN 1563 standard for 60 mm < t (wall thickness) ≤ 200 mm. Its casting technology is very difficult, and conventional casting processes cannot achieve it.

[0003] This large ductile iron wind turbine bearing seat structure needs to use chillers and risers when designing the casting process. They are used to control the solidification process of the casting, so as to obtain dense castings without shrinkage cavities and shrinkage. Whether it is simultaneous solidification control technology or sequential solidification control technology, chillers are widely used. There are two types of chillers, internal chillers and external chillers, and external chillers are more widely used. External chillers are divided into direct chillers and indirect chillers; direct chillers are in direct contact with castings, requiring the surface of the chillers to be smooth, without oxide layers and oil stains, without pores or shrinkage, and during use, the surface of the chillers must be prevented from rusting. If the above requirements are not met, defects such as wrinkles and slag on the surface of the castings will occur; in addition, direct external chillers will absorb moisture when placed for a long time, resulting in pore defects on the surface of the castings. Therefore, direct chillers are usually used in the processing area of ​​the castings, because there is usually a processing allowance in the processing area of ​​the castings, and the external defects caused by the chillers can be removed during the processing of the castings, thereby obtaining qualified castings and improving the yield rate. In the non-machined areas of the casting, indirect chilling is required.

[0004] The above-mentioned bearing seat casting belongs to large-section ductile iron. Due to the slow cooling rate, large heat capacity during casting, and slow solidification, it is very easy to cause spheroidization decay and inoculation decay, which leads to changes in the structure and matrix of the casting, especially in the thick and large section of the casting. The core part is more serious. The main manifestations are coarse graphite nodules, reduced number of graphite nodules, floating graphite, deformation of graphite nodules, and the formation of various non-spherical graphites, mainly in the form of flakes, worms, and fragments. At the same time, due to the redistribution of solute elements during solidification, there will be a series of problems such as serious element segregation and intergranular carbides and white cast iron. As a result, the mechanical properties of ductile iron deteriorate, especially the elongation and plasticity are significantly reduced; to overcome the above-mentioned shortcomings, it is very critical to speed up the cooling rate of the thick and large section of the casting; direct chiller is placed at the location of the thick and large section of the casting where the main body jacket is required to achieve a better cooling effect and meet the performance requirements of the main body jacket material. However, the existing direct chiller arrangement structure used for the above-mentioned bearing seat casting, such as the attached Figure 2As shown, the chiller arranged at the position a1 of the main body sleeve is composed of multiple rectangular chillers 1 (that is, three direct chillers arranged side by side and with gaps between them are arranged at each position a1 of the main body sleeve). This multi-piece structure is difficult to fix and easily displaced due to the impact of the core sand during the sand filling process due to the high height of the sand core filling direction. In addition, there are many rectangular chillers, and the labor intensity of moving and placing the chillers is high, which affects the production efficiency. On the other hand, there are many direct chillers and there are gaps between the chillers. After casting, excess casting residues will be left on the casting due to the effect of the gaps (the molten iron enters the gaps to form excess casting residues), resulting in an uneven surface of the casting, which requires a later grinding process. In addition, the direct chiller is too thick and too heavy to be fixed, and is easy to fall off when the sand core is demoulded, moved, or turned over, which directly affects the cooling effect of the direct chiller, the temperature field of the casting and the supply of molten iron in the riser, and the casting is prone to local shrinkage cavities and shrinkage defects. Utility Model Content

[0005] In response to the above-mentioned deficiencies in the prior art, the present application provides a direct chiller structure for casting large ductile iron wind turbine bearing seats, which can achieve effective fixation of direct chillers, is not prone to displacement during the sand filling process, has a small number of chillers, and has low labor intensity in placing chillers, and can effectively improve production efficiency.

[0006] In order to solve the above technical problems, the technical solution adopted in this application is as follows: a direct chiller structure for casting a large ductile iron wind turbine bearing seat, which structure includes a chiller body, the chiller body having at least a first surface and a second surface arranged opposite to each other, the chiller body being buried in a sand core, the first surface being located inside the sand core and a lifting lug being arranged on the first surface, the second surface being flush with an outer side surface of the sand core in which it is buried; the second surface is used to directly contact the wind turbine bearing seat casting.

[0007] By adopting the above structure, the present application sets up a whole piece of cold iron body, and buries it inside the sand core, and sets a lifting ear structure on its first surface. This scheme replaces the traditional method of setting multiple pieces of cold iron at this position, reduces the laying process of the cold iron, and improves the production efficiency; moreover, through the setting of the lifting ear, in the process of making the sand core, the core sand constituting the sand core and the lifting ear can be wrapped in the core shell, and the connection firmness between the cold iron body and the core sand can be improved. It is not easy to be impacted by the core sand during the sand filling process, and the cold iron is not easy to shift; and the cold iron used is a whole piece of structure, and no excess casting residue will appear on the surface of the casting after the casting is completed, so there is no need for grinding, saving processes and improving efficiency; on the other hand, the setting of the lifting ear can also avoid the risk of the sand core falling off easily during demoulding, moving, and flipping, thereby not affecting the cooling effect of the direct cold iron, nor affecting the temperature field of the casting and the supply of molten iron in the riser, and the casting is not easy to produce local shrinkage holes and shrinkage defects.

[0008] Furthermore, at least two lifting ears are provided, and the two lifting ears are arranged side by side along the length extension direction of the first surface; adopting this structure can further improve the connection firmness between the core sand and the direct chiller to avoid their movement.

[0009] Furthermore, four lifting ears are provided, and the four lifting ears are evenly distributed on the first surface; the above structure can improve the connection firmness between the core sand and the direct cold iron to prevent them from moving; in addition, the cold iron body can be effectively fixed by the lifting ears, and the fixing method is more balanced.

[0010] Furthermore, the cold iron body is a rectangular structure, and the first surface and the second surface are the inner surface and the outer surface of the rectangular cold iron body located in the sand core, and the first surface and the second surface are the largest surfaces of the rectangular cold iron; with this structure, five surfaces are wrapped by core sand and are also combined with the core sand through lifting ears, which can further improve the connection firmness between it and the core sand and avoid displacement during movement, sand filling or pouring; and the rectangular structure is easy to install and fix, and easy to form, and its second surface also has sufficient extension area to contact the casting, so that the poured iron liquid there can be effectively cooled and reduce the occurrence of casting defects; in addition, the area of ​​the first surface is large, and more lifting ears can be arranged to achieve a more secure wrapping and connection with the core sand.

[0011] Furthermore, the length, width and height of the rectangular cold iron body are 300mm, 230mm and 150mm respectively; the ear comprises an ear body and an ear hole in the ear body, the wall thickness of the ear body along the extension surface of the ear hole is 25m, and the ear hole is a square hole of 40mm×40mm; the spacing between the four ears along the width direction of the first surface is 100mm, and the spacing along the length direction of the first surface is 60mm.

[0012] Furthermore, the sand core includes a first sand core and a second sand core, and the first sand core and the second sand core are located on one side of the main body casing of the wind turbine bearing seat casting, and a cold iron body is pre-embedded in the first sand core and the second sand core; by adopting this structure, the traditional multi-piece cold iron structure of the main body casing of the wind turbine bearing seat casting can be replaced with the integrated cold iron body structure of this application, and the respective sand cores are firmly connected by the arrangement of the ears, which is not easy to be displaced.

[0013] The present application also provides a fixing system for the above-mentioned direct chill, which includes a core shell for preparing a sand core, the chill body being placed in the core shell, a hook being connected to the lifting ear of the chill body, one end of the hook being hooked with the lifting ear, and a holding portion being provided at the other end of the hook; with the above-mentioned structure, the hook can be first hooked into the lifting ear hole of the direct chill (large direct chill), and then the holding portion of the hook can be grasped to place the direct chill into the core shell, the distance between the direct chill and the core shell wall can be adjusted, and then the core sand can be placed and compacted, and the hook can be wrapped by the core sand to make the large direct chill in the sand core more firmly fixed.

[0014] Furthermore, at least a first gap and a second gap are formed between the cold iron body and the core shell, and the first gap and the second gap are first filled with core sand for compaction; the above scheme can effectively prevent the sand layer at the first gap position and the second gap position where the sand layer is relatively thin from detaching, falling off and being damaged, and can also avoid the displacement or falling of the large direct cold iron; firstly, the first gap part and the second gap part where the sand layer is relatively thin are compacted, and during the compaction process, due to the heavy weight of the large direct cold iron, the distance between the large direct cold iron and the core shell wall is ensured to be uniform and consistent; on the other hand, by wrapping the pull hook with core sand, the large direct cold iron is more firmly fixed in the sand core, effectively preventing the sand layer at the first gap part and the second gap part where the sand layer is relatively thin from detaching, falling off, being damaged, and the displacement or falling of the large direct cold iron. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 Schematic diagram of the structure of the wind turbine bearing seat casting.

[0016] Figure 2 Schematic diagram of the structure of the wind turbine bearing seat casting combined with the existing chiller.

[0017] Figure 3 Schematic diagram of the structure of the wind turbine bearing seat casting combined with the chiller of the present application.

[0018] Figure 4 A schematic structural diagram of the first view of direct chiller of the present application.

[0019] Figure 5 A schematic diagram of the structure of the second view of the direct cold iron of the present application.

[0020] Figure 6 A schematic structural diagram of a three-dimensional diagram of a direct chill and sand core combination of the present application.

[0021] Figure 7 A schematic structural diagram of a top view of the direct chill and sand core combination of the present application.

[0022] Figure 8 This application Figure 7 Schematic diagram of the structure of the RR direction cross-sectional view.

[0023] Fig. 9 This application Figure 7 Schematic diagram of the structure of a cross-sectional view in the transverse extension direction.

[0024] Fig.10 Schematic diagram of the structure of the first sand core and the second sand core combined with the casting in the present application.

[0025] Fig.11 This application Fig.10 Schematic diagram of the structure of the cross-sectional view in the AH-AH direction.

[0026] Fig.12 Schematic diagram of the structure of the direct cold iron and hook combination of the present application.

[0027] Fig.13 Schematic diagram of the structure of the front view of the cold iron and the hook combination.

[0028] As shown in the attached figure: a. Wind turbine bearing seat casting (or also called casting cavity), a1. Body sleeve part, 1 ， .Rectangular chill, 1. chill body, 101. first surface, 102. second surface, 103. lifting ear, 104. lifting ear body, 105. lifting ear hole, 2. sand core, 201. first sand core, 202. second sand core, 3. core shell, 4. pull hook, 401. holding part, 5. first gap, 6. second gap. DETAILED DESCRIPTION

[0029] The following will combine the embodiments and drawings to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only preferred embodiments, not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention;

[0030] It should also be noted that when a component is referred to as being "fixed to" another component, it may be directly on the other component or there may also be another intermediate component, fixed through the intermediate component. When a component is considered to be "connected" to another component, it may be directly connected to the other component or there may be another intermediate component at the same time. When a component is considered to be "set on" another component, it may be directly set on the other component or there may be another intermediate component at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those generally understood by technicians in the technical field of the present invention. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0031] The casting cavity of the present application can be the structure of the casting cavity for pouring, or the final casting structure, because the casting is obtained by first forming a cavity consistent with the casting structure, pouring molten iron in the cavity and cooling it. Therefore, the casting cavity (body) of the present application and the structure of the casting can be referred to as the same, and the structural relationship between each structure and the casting cavity body can also be seen as the structural relationship between the casting.

[0032] As attached Figure 3-9As shown, a direct chiller structure for casting a large ductile iron wind turbine bearing seat of the present application, the structure of which includes a chiller body 1, the chiller body 1 having at least a first surface 101 and a second surface 102 arranged opposite to each other (i.e., the chiller body is a rectangular structure, and the first surface and the second surface are the oppositely arranged outer surfaces of the maximum area of ​​the rectangular structure, i.e., two surfaces arranged opposite to each other along the thickness direction), the chiller body 1 is buried in a sand core 2 (the sand core is formed by sand casting of core sand and a built-in chiller body), the first surface 101 is located inside the sand core 2 and a lifting lug 103 is arranged on the first surface 101, the second surface 102 is flush with an outer side surface of the sand core 2 in which it is buried (the chiller body is arranged in a sand core formed by molding sand, and the second surface is exposed from the sand core, so that the second surface is in direct contact with the casting to achieve the effect achieved by direct chiller); the second surface 102 is used to directly contact the wind turbine bearing seat casting a.

[0033] By adopting the above structure, the present application sets up a whole piece of chiller body, and buries it inside the sand core, and sets a lifting ear structure on its first surface. This scheme replaces the traditional method of setting multiple pieces of chiller at this position, reduces the laying process of chiller and improves the production efficiency; moreover, through the setting of the lifting ear, in the process of making the sand core, the core sand constituting the sand core and the lifting ear can be wrapped in the core shell, and the connection firmness between the chiller body and the core sand can be improved. In the process of filling sand, it is not easy to be impacted by the core sand, and the chiller is not easy to shift; and the chiller used is a whole piece of structure After the casting is completed, no excess casting residue will appear on the surface of the casting, so there is no need for grinding, which saves processes and improves efficiency. On the other hand, the setting of the lifting lugs can also avoid the risk of the sand core falling off during demoulding, moving, and turning over, thereby not affecting the cooling effect of the direct chill, the temperature field of the casting, and the supply of molten iron in the riser, and the casting is not prone to local shrinkage cavities and shrinkage defects. In addition, an integrated chill body is pre-embedded in the core sand to form a part of the sand core structure, which can also play the role of a core bone inside to improve the strength of the overall sand core.

[0034] As an example, at least two lifting ears 103 described in the present application are provided, and the two lifting ears 103 are arranged side by side along the length extension direction of the first surface 101; adopting this structure, the connection firmness between the core sand and the direct chill can be further improved to prevent them from moving.

[0035] As attached Figure 4-5As shown, as an example, the present application provides four lifting ears 103, and the four lifting ears 103 are evenly distributed on the first surface 101; the above structure can improve the connection firmness between the core sand and the direct chiller to prevent movement; in addition, the chiller body can be effectively fixed by the lifting ears, and the fixing method is more balanced.

[0036] As attached Figure 4-5 As shown, the cold iron body 1 described in the present application is a rectangular structure, and the first surface 101 and the second surface 102 are the inner surface and the outer surface of the rectangular body located in the sand core, and the first surface 101 and the second surface 102 are the largest surfaces of the rectangular cold iron; with this structure, five faces are wrapped by the core sand, and are also combined with the core sand through the lifting ears, which can further improve the connection firmness between it and the core sand, and avoid displacement during movement, sand filling or pouring; and the rectangular structure is easy to install and fix, and easy to form, and its second surface also has a sufficient extension area to contact the casting, so that the poured iron liquid there can be effectively cooled and reduce the occurrence of casting defects; in addition, the large area of ​​the first surface can arrange more lifting ears to achieve a more secure wrapping and connection with the core sand; with this structure, five faces are wrapped by the core sand, and are also combined with the core sand through the lifting ears, which can further improve the connection firmness between it and the core sand, and avoid displacement during movement, sand filling or pouring.

[0037] As an example, the length, width and height of the rectangular cold iron body 1 described in the present application are 300mm, 230mm and 150mm respectively; the ear 103 includes an ear body 104 and an ear hole 105 located in the ear body 104, the wall thickness of the ear body 104 along the extension surface of the ear hole is 25m, and the ear hole 105 is a square hole of 40mm×40mm; the spacing between the four ears 103 along the width direction of the first surface 101 is 100mm, and the spacing along the length direction of the first surface 101 is 60mm.

[0038] As attached Figure 10-11 As shown, the sand core 2 described in the present application includes a first sand core 201 and a second sand core 202, and the first sand core 201 and the second sand core 202 are located on one side of the main body casing of the wind turbine bearing seat casting a, and the first sand core 201 and the second sand core 202 are both pre-embedded with a cold iron body 1; by adopting this structure, the traditional multi-piece cold iron structure of the main body casing of the wind turbine bearing seat casting can be replaced with the integrated cold iron body structure of this application, and the ears are set on each sand core to achieve a stable connection, which is not easy to be displaced.

[0039] As attached Figure 7-13As shown, the present application also provides a fixing system for the above-mentioned direct chiller, which fixing system includes a core shell 3 for preparing a sand core 2 (the core shell is a hollow structure, the contour of the hollow inner cavity is consistent with the outer shape of the sand core to be prepared, and then the core sand is buried in the inner cavity (the core sand can be composed of molding sand and adhesives commonly used in the casting field), and the final sand core structure is formed), the chiller body 1 is placed in the core shell 3, and the ear 103 of the chiller body 1 is connected with a hook 4, and one end of the hook 4 is connected to the The hook 4 is hooked with the ear 103, and the other end of the hook is provided with a gripping portion 401; with the above structure, the hook can be hooked into the ear hole of the direct chill (large direct chill), and then the gripping portion of the hook can be grasped to put the direct chill into the core shell, and the distance between the direct chill and the core shell wall can be adjusted (the direct chill with the adjusted distance can be fixed or held all the time), and then the core sand can be put in and compacted, and the core sand can be wrapped around the hook and the outer surface of the chill, so that the large direct chill can be fixed more firmly in the sand core.

[0040] As attached Figure 8 As shown, at least a first gap 5 and a second gap 6 are formed between the cold iron body 1 and the core shell 3 of the present application, and the first gap 5 and the second gap 6 are first filled with core sand for compaction; that is, the first gap and the second gap at this time are Figure 8 A relatively narrow gap is formed between the middle chiller body and the core shell. The core sand formed by filling sand here is relatively thin and easy to detach from the chiller. By adopting the above scheme, the weak positions are filled first, which can effectively prevent the detachment, falling off and damage of the sand layer at the first gap position and the second gap position where the sand layer is relatively thin, and can also avoid the displacement or falling of the large direct chiller. First, the first gap position and the second gap position where the sand layer is relatively thin are tightened. During the tightening process, due to the heavy weight of the large direct chiller, the spacing between the large direct chiller and the core shell wall is ensured to be uniform and consistent. On the other hand, by wrapping the pull hook with the core sand, the large direct chiller is fixed more firmly in the sand core, which effectively prevents the detachment, falling off and damage of the sand layer at the first gap position and the second gap position where the sand layer is relatively thin, as well as the displacement or falling of the large direct chiller.

[0041] The above-mentioned technical scheme of the present application adopts an integrated one-piece chiller structure to replace the existing multi-piece chiller structure, thereby saving the amount of chiller and making it easier to operate; moreover, the integrated chiller structure adopted in the present application can enhance the wrapping force between it and the core sand of the filling sand core by arranging a lifting ear on it, improve the connection firmness between the chiller and the core sand, and avoid displacement of the chiller; in addition, the present application also arranges a hook structure on the lifting ear, which can further fix the position of the chiller, and can also wrap the hook with the core sand to further stabilize the position of the chiller and the connection with the core sand, so that the direct chiller is not easy to fall off when the sand core is demoulded, moved, and turned over, and will not affect the cooling effect of the direct chiller, nor will it affect the temperature field of the casting and the supply of molten iron in the riser, and the casting is not easy to produce defects such as local shrinkage cavities and shrinkage; moreover, the chiller and the hook are buried in the core sand constituting the sand core, which can act as the core bone of the sand core and improve the overall strength of the sand core.

Claims

1. A direct chiller for a wind turbine bearing seat, characterized in that: Its structure includes a cold iron body, which has at least a first surface and a second surface arranged opposite to each other. The cold iron body is buried in a sand core, the first surface is located inside the sand core and a lifting lug is arranged on the first surface, and the second surface is flush with an outer side surface of the sand core in which it is buried; the second surface is used to directly contact the wind power bearing seat casting.

2. The direct chiller of the wind turbine bearing seat according to claim 1, characterized in that: At least two lifting ears are provided, and the two lifting ears are arranged side by side along the length extension direction of the first surface.

3. The direct chiller of the wind turbine bearing seat according to claim 2 is characterized in that: There are four hanging ears, and the four hanging ears are evenly distributed on the first surface.

4. The direct chiller of the wind turbine bearing seat according to claim 3 is characterized in that: The chill body is a rectangular parallelepiped structure, the first surface and the second surface are the inner surface and the outer surface of the rectangular parallelepiped chill body located in the sand core, and the first surface and the second surface are the largest surfaces of the rectangular parallelepiped chill.

5. The direct chiller of the wind turbine bearing seat according to claim 4, characterized in that: The length, width and height of the rectangular cold iron body are 300mm, 230mm and 150mm respectively; the ear comprises an ear body and an ear hole in the ear body, the wall thickness of the ear body along the extension surface of the ear hole is 25m, and the ear hole is a square hole of 40mm×40mm; the spacing between the four ears along the width direction of the first surface is 100mm, and the spacing along the length direction of the first surface is 60mm.

6. The direct chiller of the wind turbine bearing seat according to claim 1, characterized in that: The sand core comprises a first sand core and a second sand core, the first sand core and the second sand core are located on one side of the body sleeve of the wind power bearing seat casting, and the first sand core and the second sand core are both pre-embedded with a chiller body.

7. A direct chiller fixing system for a wind turbine bearing seat according to any one of claims 1 to 6, characterized in that: The fixing system comprises a core shell for preparing a sand core, the cold iron body is placed in the core shell, a hook is connected to the lifting ear of the cold iron body, one end of the hook is hooked with the lifting ear, and the other end of the hook is provided with a gripping portion.

8. The fixing system according to claim 7, characterized in that: At least a first gap and a second gap are formed between the cold iron body and the core shell, and the first gap and the second gap are first filled with core sand for compaction.

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