A casting mold and a casting method of a voltage transformer

Abstract

The application relates to the technical field of high-voltage voltage transformer manufacturing, and discloses a pouring mold and a pouring method for a voltage transformer, a pouring mold for a voltage transformer, which comprises a box body, an upper cover and a feeding channel; the box body is provided with a pouring cavity, the pouring cavity is divided into an upper section, a middle section and a lower section, and the top of the box body is provided with an opening which is communicated with the pouring cavity; the upper cover covers the opening, the upper cover is provided with a first exhaust hole which is communicated with the pouring cavity; the feeding channel comprises a feeding port and a feeding pipeline, the feeding port is connected to the upper cover, and the upper end of the feeding pipeline is communicated with the feeding port and the lower end is communicated with the lower section; the pouring mold can produce the voltage transformer with less surface defects and high appearance quality; the pouring method can produce the voltage transformer product with small partial discharge, high load capacity, long service period and high pollution level.

Description

Technical Field

[0001] This invention relates to the field of high voltage transformer manufacturing technology, and in particular to a casting mold and casting method for a voltage transformer. Background Technology

[0002] The existing casting mold for voltage transformers has only one upper pouring port. When using this type of casting mold, the casting material enters the mold cavity from the top of the mold. After the casting is completed, a large amount of gas inside the casting material cannot be expelled in time, resulting in a large number of defects on the surface of the cast high voltage transformer, which require repair and have low appearance quality. Summary of the Invention

[0003] The purpose of this invention is to provide a casting mold capable of producing voltage transformers with few surface defects and high appearance quality, as well as a casting method applied to the casting mold.

[0004] To achieve the above objectives, the present invention provides a casting mold for a voltage transformer, comprising a housing, a top cover, and a feeding channel;

[0005] The box body has a casting cavity, which is divided into an upper section, a middle section and a lower section from top to bottom. The top of the box body has an opening that communicates with the casting cavity.

[0006] The upper cover is disposed above the box body and covers the opening, and the upper cover has a first vent hole communicating with the casting cavity;

[0007] The feeding channel includes a feeding port and a feeding pipe. The feeding port is connected to the upper cover, and the upper end of the feeding pipe is connected to the feeding port, while the lower end is connected to the lower section.

[0008] Preferably, the housing has the feed pipe.

[0009] Preferably, the casting mold further includes a bypass venting channel, the bypass venting channel including an venting pipe and a second venting hole communicating with the venting pipe, the upper end of the venting pipe communicating with the upper section and the lower end extending to the middle section, and the second venting hole communicating with the middle section.

[0010] Preferably, the housing has the exhaust pipe.

[0011] Preferably, the casting mold further includes a vent, which is connected to the upper cover and communicates with the casting cavity.

[0012] Preferably, the inner wall of the intermediate section has an inwardly recessed annular groove, and the inner wall of the annular groove has the second vent hole.

[0013] More preferably, each of the annular grooves is connected to the exhaust pipe via at least one of the second exhaust holes.

[0014] More preferably, there are multiple annular grooves, and the multiple annular grooves are arranged alternately from top to bottom.

[0015] Preferably, it further includes a guide slide, which is fixed to the upper surface of the housing, and the upper cover contacts the guide slide and can cover or expose the opening along the guide slide.

[0016] More preferably, the guide slide includes a fixed part and a guide slide part. The fixed part is connected to the upper surface of the housing. The upper end of the fixed part is bent toward the upper cover to form the guide slide part. A groove is formed between the lower surface of the guide slide part and the upper surface of the housing.

[0017] The number of the guide slide components is two;

[0018] Both outer walls of the top cover have outwardly extending sliding portions that extend into the groove and contact the inner wall of the groove.

[0019] More preferably, the guide slide is detachably fixed to the housing.

[0020] More preferably, a handle is fixed to the upper surface of the cover.

[0021] Preferably, the housing includes a first half-mold and a second half-mold detachably connected to the first half-mold, wherein the casting cavity is formed between the inner wall of the first half-mold and the inner wall of the second half-mold.

[0022] More preferably, the first half-mold is detachably connected to the second half-mold via a latch, and handles are fixed on the outer walls of both the first half-mold and the second half-mold.

[0023] Preferably, the casting mold further includes two rotating shafts, which are respectively fixed to the outer walls of the two sides of the box body.

[0024] The present invention also provides a method for casting a voltage transformer, the method comprising the following steps: casting using the casting mold described in any of the preceding claims.

[0025] Vessel body installation: The vessel body is installed into the pouring cavity of the pouring mold;

[0026] Loading into the vacuum casting tank: Load the casting mold into the vacuum casting tank, evacuate and heat the vacuum casting tank, and inject SF6 gas into the vacuum casting tank;

[0027] Loading into the large vacuum casting tank: Load the small vacuum casting tank into the large vacuum casting tank, and connect the casting pipe of the large vacuum casting tank to the casting pipe of the small vacuum casting tank; evacuate and heat the large vacuum casting tank, and inject the casting material into the casting cavity until the casting cavity is full;

[0028] Curing process: The completed casting mold is transferred into a curing oven for curing.

[0029] Demolding: Disassemble the casting mold and remove the finished voltage transformer.

[0030] First, a vacuum casting tank is used to create a vacuum and heat it, and then SF6 protective gas is injected. Then, a large vacuum casting tank is used to ensure the vacuum level and temperature during the casting process. This provides the best casting conditions for the casting process, resulting in a voltage transformer product with low partial discharge, strong load-carrying capacity, long service life, and high pollution level.

[0031] Compared with the prior art, the casting mold for a voltage transformer according to an embodiment of the present invention has the following advantages: by extending the lower end of the feed pipe to the lower section, the casting material can be poured to the bottom of the casting cavity, and the casting material can slowly rise from the bottom of the casting cavity, which is conducive to maximizing the discharge of gas from the casting cavity through the first vent hole, reducing the adverse effects of gas on the casting process, and improving the appearance quality of the finished voltage transformer. Therefore, the casting mold of the present invention can produce voltage transformers with fewer surface defects and higher appearance quality.

[0032] Compared with the prior art, the casting method of the voltage transformer of the present invention has the following advantages: by applying any of the above-mentioned casting molds and adopting the method of large tank inside small tank, the gas in the casting cavity can be emptied as much as possible through the casting mold, and the method of casting a large vacuum tank inside a small vacuum tank can ensure the best casting conditions, thereby producing a voltage transformer finished product with low partial discharge, strong load carrying capacity, long service life and high pollution level. Attached Figure Description

[0033] Figure 1 This is a perspective view of a casting mold for a voltage transformer provided in an embodiment of the present invention;

[0034] Figure 2 This is a top view of a casting mold for a voltage transformer provided in an embodiment of the present invention;

[0035] Figure 3 This is a front view of a casting mold for a voltage transformer provided in an embodiment of the present invention;

[0036] Figure 4This is a cross-sectional view of a casting mold for a voltage transformer provided in an embodiment of the present invention;

[0037] Figure 5 This is provided by the embodiments of the present invention. Figure 4 Enlarged view of point A;

[0038] Figure 6 This is a side view of a casting mold for a voltage transformer provided in an embodiment of the present invention;

[0039] Figure 7 This is a side view of a voltage transformer casting mold without a top cover, according to an embodiment of the present invention.

[0040] Figure 8 This is a perspective view of the top cover provided in an embodiment of the present invention;

[0041] Figure 9 This is a schematic diagram of a voltage transformer casting mold connected to a mobile trolley, according to an embodiment of the present invention.

[0042] In the diagram, 1 is the housing; 11 is the upper section; 12 is the middle section; 13 is the lower section; 121 is the annular groove; 101 is the first half mold; 102 is the second half mold; 103 is the latch; and 104 is the handle.

[0043] 2. Top cover; 21. First vent; 22. Sliding part; 23. Handle;

[0044] 3. Feeding channel; 31. Feeding inlet; 32. Feeding pipe;

[0045] 4. Exhaust pipe;

[0046] 6. Guide slide; 61. Fixed part; 62. Guide slide; 63. Slide groove;

[0047] 7. Shaft;

[0048] 8. Exhaust port;

[0049] 100. Mobile trolley; 200. Support frame; 201. Upright pole; 202. U-shaped channel. Detailed Implementation

[0050] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and are not intended to limit the scope of the invention.

[0051] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0052] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature.

[0053] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0054] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0055] like Figure 1-5 As shown, a preferred embodiment of the present invention provides a casting mold for a voltage transformer, comprising a housing 1, a top cover 2, and a feeding channel 3.

[0056] The housing 1 has a casting cavity, which is divided into an upper section 11, a middle section 12, and a lower section 13 from top to bottom. The top of the housing 1 has an opening that communicates with the casting cavity. The upper cover 2 is located above the housing 1 and covers the opening. The upper cover 2 has a first vent 21 that communicates with the casting cavity. The feeding channel 3 includes a feeding port 31 and a feeding pipe 32. The feeding port 31 is connected to the upper cover 2. The upper end of the feeding pipe 32 communicates with the feeding port 31, and the lower end communicates with the lower section 13.

[0057] Based on this technical solution, by extending the lower end of the feed pipe 32 to the lower section 13, the casting material can be poured to the bottom of the casting cavity, and the casting material can slowly rise from the bottom of the casting cavity, which is conducive to maximizing the discharge of gas from the casting cavity through the first exhaust hole 21, thereby reducing the adverse effects on the casting process and improving the appearance quality of the finished voltage transformer.

[0058] In this embodiment, the feed pipe 32 is a feed groove formed on the side wall of the casting cavity.

[0059] It should be noted that the casting mold described in this embodiment is used for casting 35KV voltage transformers.

[0060] See Figures 4-5 The casting mold provided in this embodiment of the invention also includes a bypass venting channel. The bypass venting channel includes an venting pipe 4 and a second venting hole connected to the venting pipe 4. The upper end of the venting pipe 4 is connected to the upper section 11 and the lower end extends to the middle section 12. The second venting hole is connected to the middle section 12.

[0061] Preferably, the exhaust pipe 4 is an exhaust groove formed on the side wall of the casting cavity.

[0062] Preferably, the casting mold further includes a vent 8, which is connected to the upper cover 2 and communicates with the casting cavity.

[0063] Preferably, the inner wall of the intermediate section 12 has an inwardly recessed annular groove 121, and the inner wall of the annular groove 121 has the second exhaust hole.

[0064] More preferably, each of the annular grooves 121 is connected to the exhaust pipe 4 through at least one of the second exhaust holes.

[0065] The annular groove 121 is used to form the insulating skirt of the voltage transformer during the casting process. By setting the second vent hole on the inner wall of the annular groove 121, the gas in the annular groove 121 can be discharged, reducing the adverse effects of the gas during the casting process on the insulating skirt of the finished voltage transformer, improving the casting quality of the finished voltage transformer, and thus enabling the production of finished voltage transformers with low partial discharge, strong load-carrying capacity, long service life, and high pollution level.

[0066] Preferably, there are multiple annular grooves 121, and the multiple annular grooves 121 are arranged alternately from top to bottom.

[0067] See Figure 6-7 The box 1 provided in this embodiment of the invention includes a first half mold 101 and a second half mold 102 detachably connected to the first half mold 101, and the casting cavity is formed between the inner wall of the first half mold 101 and the inner wall of the second half mold 102.

[0068] The first half mold 101 is detachably connected to the second half mold 102 via a latch 103, and handles 104 are fixed on the outer walls of both the first half mold 101 and the second half mold 102.

[0069] By using a detachable top cover 2, a first half mold 101, and a second half mold 102, modular component assembly of the voltage transformer casting mold can be realized, which has the advantages of high modifiability and high reusability.

[0070] See Figures 7-8 The casting mold provided in this embodiment of the invention further includes a guide slide 6, which is fixed to the upper surface of the housing 1. The upper cover 2 contacts the guide slide 6 and can cover or expose the opening along the guide slide 6. Using the guide slide 6 facilitates the quick covering or exposure of the casting cavity by the upper cover 2, and also facilitates the disassembly and installation of the upper cover 2 and the housing 1.

[0071] Preferably, the guide slide 6 includes a fixing part 61 and a guide slide part 62. The fixing part 61 is connected to the upper surface of the housing 1, and the upper end of the fixing part 61 bends towards the upper cover 2 to form the guide slide part 62. A groove 63 is formed between the lower surface of the guide slide part 62 and the upper surface of the housing 1. There are two guide slides 6. Both outer walls of the upper cover 2 have outwardly extending sliding portions 22, which extend to the groove 63 and contact the inner wall of the groove 63. Using the groove 63 and the sliding portion 22, the upper cover 2 can quickly cover or expose the casting cavity, and can also be fixed between the guide slide 6 and the housing 1.

[0072] Preferably, the guide slide 6 is detachably fixed to the housing 1.

[0073] Specifically, the guide slide 6 is bolted to the housing 1.

[0074] Preferably, the two guide slides 6 are fixed to the top of the first half mold 101 and the second half mold 102, respectively.

[0075] Preferably, a handle 23 is fixed to the upper surface of the upper cover 2. The handle 23 facilitates the quick covering or exposure of the casting cavity by the upper cover 2, and also facilitates the hoisting and holding of the casting mold.

[0076] Specifically, the handle 23 is a T-shaped handle.

[0077] See Figure 1-2 and combined Figure 9 It is understood that the casting mold provided in this embodiment of the invention also includes two rotating shafts 7, and the two rotating shafts 7 are respectively fixed on the outer walls of the two sides of the box body 1.

[0078] The rotating shaft 7 can cooperate with the support 200 of the moving trolley 100 so that the casting mold can rotate around the central axis of the rotating shaft 7, thereby facilitating the demolding of the casting mold.

[0079] The bracket 200 is fixed to the upper surface of the mobile trolley 100. The bracket 200 includes two uprights 201. The upper end of the uprights 201 has a downwardly recessed U-shaped groove 202. When the casting mold is hoisted to the bracket 200, the two rotating shafts 7 are respectively placed in the two U-shaped grooves 202, so that the casting mold can rotate around the central axis of the rotating shafts 7 on the bracket 200, thereby facilitating the demolding operation of the voltage inductor casting mold.

[0080] This invention also provides a method for casting a voltage transformer, which uses any of the casting molds described above for casting, and includes the following steps:

[0081] Vessel body installation: The vessel body is installed into the pouring cavity of the pouring mold;

[0082] Loading into the vacuum casting tank: Load the casting mold into the vacuum casting tank, evacuate and heat the vacuum casting tank, and inject SF6 gas into the vacuum casting tank;

[0083] Loading into the large vacuum casting tank: Load the small vacuum casting tank into the large vacuum casting tank, and connect the casting pipe of the large vacuum casting tank to the casting pipe of the small vacuum casting tank; evacuate and heat the large vacuum casting tank, and inject the casting material into the casting cavity until the casting cavity is full;

[0084] Curing process: The completed casting mold is transferred into a curing oven for curing.

[0085] Demolding: Disassemble the casting mold and remove the finished voltage transformer.

[0086] First, a vacuum casting tank is used to create a vacuum and heat it, and then SF6 protective gas is injected. Then, a large vacuum casting tank is used to ensure the vacuum level and temperature during the casting process. This provides the best casting conditions for the casting process, resulting in a voltage transformer product with low partial discharge, strong load-carrying capacity, long service life, and high pollution level.

[0087] By applying the casting mold and using a large-can-within-a-small-can method, the gas in the casting cavity can be emptied as much as possible through the casting mold, and the optimal casting conditions can be ensured by casting a large vacuum can inside a small vacuum can. This allows for the production of voltage transformer finished products with low partial discharge, strong load-carrying capacity, long service life, and high pollution levels.

[0088] It should be noted that the casting method in this embodiment is applied to the production of 35KV voltage transformers.

[0089] In summary, the casting mold for a voltage transformer provided in this embodiment of the invention has the following beneficial effects:

[0090] 1. By extending the lower end of the feed pipe 32 to the lower section 13 and communicating with the lower section 13, the casting material can be poured to the bottom of the casting cavity, and the casting material can slowly rise from the bottom of the casting cavity. This facilitates the maximum discharge of gas from the casting cavity through the first exhaust hole 21, which can reduce the adverse effects on the casting process and improve the appearance quality of the finished voltage transformer.

[0091] 2. By using the bypass venting channel, the gas in the middle section 12 can be discharged along the path of the second venting hole, the venting pipe 4, the upper section 11 and the first venting hole 21 during the process of the casting material entering the casting cavity. This is beneficial to completely remove the internal gas of the casting material in the casting cavity and improve the appearance quality of the finished voltage transformer.

[0092] 3. By adopting the method of having the second vent hole on the inner wall of the annular groove 121, the adverse effects of gas during the casting process on the insulating skirt of the voltage transformer product can be reduced, thereby enabling the cast voltage transformer product to have the advantages of low partial discharge, strong load-carrying capacity, long service life, and high pollution level.

[0093] 4. The guide slide 6 is used to facilitate the quick covering or exposure of the casting cavity by the upper cover 2, and also to facilitate the disassembly and installation between the upper cover 2 and the box body 1.

[0094] 5. By employing the fixed part 61, the guide part 62, and the slide groove 63, the upper cover 2 can both quickly cover or expose the casting cavity through the slide groove 63, and can also be fixed between the guide part 6 and the box body 1.

[0095] 6. The handle 23 facilitates the quick covering or exposure of the casting cavity by the upper cover 2, and also facilitates the hoisting and hand-holding stabilization of the casting mold.

[0096] 7. By adopting a detachable top cover 2, a first half mold 101 and a second half mold 102, modular assembly of the voltage transformer casting mold can be realized, giving the casting mold the advantages of high modifiability and high reusability.

[0097] 8. By using the rotating shaft 7, the casting mold can be rotated around the central axis of the rotating shaft 7 during the demolding process, thereby facilitating the quick disassembly of the various components of the casting mold.

[0098] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and substitutions can be made without departing from the technical principles of the present invention, and these improvements and substitutions should also be considered within the scope of protection of the present invention.

Claims

1. A casting mold for a voltage transformer, characterized in that, include: The box body has a casting cavity, which is divided into an upper section, a middle section and a lower section from top to bottom, and the top of the box body has an opening communicating with the casting cavity; The top cover is disposed above the box body and covers the opening, and the top cover has a first vent hole communicating with the casting cavity; The feeding channel includes a feeding port and a feeding pipe. The feeding port is connected to the upper cover, and the upper end of the feeding pipe is connected to the feeding port and the lower end is connected to the lower section. It also includes a bypass exhaust channel, which includes an exhaust pipe and a second exhaust port communicating with the exhaust pipe. The upper end of the exhaust pipe is connected to the upper section and the lower end extends to the middle section. The second exhaust port is connected to the middle section. The inner wall of the intermediate section has an inwardly recessed annular groove, and the inner wall of the annular groove has a second vent hole.

2. The casting mold according to claim 1, characterized in that, The number of annular grooves is multiple, and the multiple annular grooves are arranged alternately from top to bottom.

3. The casting mold according to claim 1, characterized in that, It also includes a guide slide, which is fixed to the upper surface of the housing. The upper cover contacts the guide slide and can cover or expose the opening along the guide slide.

4. The casting mold according to claim 3, characterized in that, The guide slide includes a fixed part and a guide slide part. The fixed part is connected to the upper surface of the box body. The upper end of the fixed part is bent towards the upper cover to form the guide slide part. A sliding groove is formed between the lower surface of the guide slide part and the upper surface of the box body. The number of the guide slide components is two; Both outer walls of the top cover have outwardly extending sliding portions that extend into the groove and contact the inner wall of the groove.

5. The casting mold according to claim 4, characterized in that, A handle is fixed to the upper surface of the cover.

6. The casting mold according to claim 1, characterized in that, The box body includes a first half mold and a second half mold detachably connected to the first half mold, and the casting cavity is formed between the inner wall of the first half mold and the inner wall of the second half mold.

7. The casting mold according to claim 1, characterized in that, It also includes two rotating shafts, which are fixed to the outer walls of the two sides of the housing, respectively.

8. A method for casting a voltage transformer, characterized in that, The method utilizes the casting mold as described in any one of claims 1-7 for casting, and includes the following steps: Vessel body installation: The vessel body is installed into the pouring cavity of the pouring mold; Loading into the vacuum casting tank: Load the casting mold into the vacuum casting tank, evacuate and heat the vacuum casting tank, and inject SF6 gas into the vacuum casting tank; Loading into the large vacuum casting tank: Load the small vacuum casting tank into the large vacuum casting tank, and connect the casting pipe of the large vacuum casting tank to the casting pipe of the small vacuum casting tank; evacuate and heat the large vacuum casting tank, and inject the casting material into the casting cavity until the casting cavity is full; Curing process: The completed casting mold is transferred into a curing oven for curing. Demolding: Disassemble the casting mold and remove the finished voltage transformer.

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