Small shell baking tooling suitable for fast melting process

Abstract

The utility model relates to a small -size form shell baking frock suitable for fast melting technology, including lower base, lower base includes: base body, first jack, be located on the base body, one end of first jack is first insertion, and first jack is through first insertion and the upper end surface of base body and penetrates, first support part, be located in the inner wall of first jack, are used for supporting the crucible in the vertical direction below the crucible, the upper end of the crucible is fixed with product, and the product is located above first insertion, and the cavity is located in the crucible, first channel, be located on the base body, and first channel will first jack and the outside of base body and communicate, wherein, when the crucible is directly inserted into first jack, the lower end of the crucible is in contact with first support part, and the inner diameter of first jack is adapted to the diameter of the crucible, and the cavity is communicated with first channel. Thus, in the baking process, the form shell and wax mould can realize complete baking, and the inclusion rate of the casting is reduced.

Description

Technical Field

[0001] This utility model relates to the field of precision casting technology, and in particular to a small mold shell firing fixture suitable for fast melting process. Background Technology

[0002] In the precision casting industry, traditional mold shell baking uses a universal chassis support to support the product to be baked (mold shell + wax pattern) in the baking furnace. For small products formed by fast melting process, the design of the baking fixture needs to consider the crucible (tubular structure with a cavity for placing metal rods and connected to the mold shell) to fix the product. Usually, a support with an upward-facing insertion hole is used as the baking fixture. After the crucible is inserted into the insertion hole, it is ensured that the product and the crucible are in an upright state.

[0003] However, the mold shells produced using the above-mentioned baking fixtures are prone to incomplete firing, and the lower end of the crucible is also prone to incomplete firing, resulting in a high inclusion rate in castings produced using the above-mentioned mold shells, which can reach more than 6%. Utility Model Content

[0004] In response to the shortcomings of the existing production technology, the applicant provides a small mold shell baking fixture suitable for fast melting process, so that both the mold shell and the wax mold can be fully baked during the baking process, thereby reducing the inclusion rate of the casting.

[0005] The technical solution adopted in this utility model is as follows:

[0006] A small mold shell firing fixture suitable for rapid melting process includes a lower base, the lower base comprising:

[0007] Base body;

[0008] A first socket is provided on the base body, one end of the first socket is a first insertion port, and the first socket is connected to the upper surface of the base body through the first insertion port;

[0009] A first support portion is provided on the inner wall of the first insertion hole for vertically supporting the crucible below it. A product is fixed at the upper end of the crucible, and the product is located above the first insertion hole. A cavity is provided inside the crucible.

[0010] A first channel is provided on the base body, and the first channel connects the first socket to the outside of the base body;

[0011] When the crucible is directly inserted into the first insertion hole, the lower end of the crucible contacts the first support part, the inner diameter of the first insertion hole is adapted to the diameter of the crucible, and the cavity is connected to the first channel.

[0012] As a further improvement to the above technical solution:

[0013] The first channel is arranged radially along the first insertion hole.

[0014] The first support part has a ring-shaped structure, and a notch is provided at the position corresponding to the first channel. The first channel is connected to the side wall of the first insertion hole at the notch through the notch.

[0015] The first channel extends axially along the first insertion hole to the upper end face of the base body and passes through the first insertion hole.

[0016] The number of the first channels is multiple, and they are evenly distributed in an array with the axis of the first socket as the center.

[0017] The first support portion is block-shaped, and there are multiple of them. They are spaced apart along the circumferential direction of the inner wall of the first insertion hole, and each first channel is located between two adjacent first support portions.

[0018] It also includes an upper base, the upper base comprising:

[0019] A connecting shaft, wherein the first insertion hole is adapted to the diameter of the connecting shaft, and the first support portion is used to support the connecting shaft vertically from one end of the connecting shaft;

[0020] The second insertion hole is located at the center of the connecting shaft and extends through both ends of the connecting shaft along the axial direction. The second insertion hole is adapted to the diameter of the crucible and communicates with the first insertion hole. The inner wall of the second insertion hole is provided with a second support portion, which is used to support the lower end face of the crucible so that the product is located outside the second insertion hole.

[0021] When the crucible is directly inserted into the second insertion hole, the connecting shaft is inserted into the first insertion hole, the lower end of the crucible contacts the second support part, and the cavity communicates with the first channel.

[0022] The inner wall of the second socket is provided with multiple grooves, which are evenly distributed around the axis of the second socket. The length direction of each groove is set along the axial direction of the second socket. One end of the groove is located on the upper end face of the connecting shaft, and the other end of the groove is in the same axial position as the support surface of the second support part.

[0023] An extension is provided on one end of the connecting shaft located outside the first socket. The extension is provided with a plug-in part, which is plugged into the base body and is used to position the connecting shaft along the circumferential direction of the inner wall of the first socket.

[0024] The product includes a mold shell connected to the crucible and a wax mold located inside the mold shell. After firing, the cavity inside the mold shell is connected to the hollow cavity.

[0025] The beneficial effects of this utility model are as follows:

[0026] This utility model has a compact and reasonable structure and is easy to operate. By setting a first channel on the base body and connecting the first insertion hole for supporting and fixing the crucible through the first channel, it is convenient to discharge and renew the gas in the cavity during the firing process, so that both the product and the crucible can be fully fired, reducing the inclusion rate of the casting.

[0027] This utility model also has the following advantages:

[0028] (1) Multiple first channels are set with the axis of the first insertion hole as the center, and the first channels are made to penetrate the upper end face of the base body along the axis direction, so that the inner wall of the first insertion hole is uniformly connected with the outside, and multiple airflow channels are uniformly introduced to make the product and crucible heat evenly.

[0029] (2) The first support part, which is set at intervals, enables good communication between the lower end face and outer peripheral face of the crucible and the first channel.

[0030] (3) The connecting shaft of the upper base is directly inserted into the first insertion hole of the lower base, so that the upper base is mounted on the lower base to reduce the size of the insertion hole that directly supports the crucible. At the same time, the second insertion hole of the upper base is connected to the first channel, thereby ensuring that the cavity of the crucible is connected to the first channel. When both the product and the crucible can be fully roasted, the combined roasting fixture is adapted to the small-sized crucible, and the roasting fixture can be quickly changed without stopping the furnace.

[0031] (4) Multiple grooves along the axial direction are provided on the inner wall of the second insertion hole. A second channel is formed between the groove and the outer wall of the crucible. There is also a gap between the lower end face of the crucible and the second support part, which realizes the connection between the second channel and the cavity. The second channel provides good gas flow space for the outer wall and end of the crucible, realizes good gas flow and renewal, and makes the crucible roasting effect more complete, solving the problem of roasting residue at the lower end of small crucibles. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the roasting fixture structure according to Embodiment 1 of this utility model.

[0033] Figure 2 This is a cross-sectional view of the roasting fixture in Embodiment 1 of this utility model.

[0034] Figure 3 This is a schematic diagram of the roasting fixture structure in Embodiment 2 of this utility model.

[0035] Figure 4This is a cross-sectional view of the roasting fixture in Embodiment 2 of this utility model.

[0036] Figure 5 for Figure 4 Enlarged view of a portion of point A in the middle.

[0037] Figure 6 This is a schematic diagram of the lower base structure according to an embodiment of the present utility model.

[0038] Figure 7 This is a schematic diagram of the upper base structure according to an embodiment of the present utility model.

[0039] Figure 8 This is a schematic diagram of the upper base structure of an embodiment of the present utility model (from another perspective).

[0040] in:

[0041] 1. Product; 2. Crucible; 21. Cavity;

[0042] 3. Lower base; 31. First channel; 32. Base body; 33. First insertion hole; 34. First support part; 35. Positioning hole;

[0043] 4. Upper base; 41. Insertion part; 42. Extension part; 43. Second insertion hole; 44. Connecting shaft; 45. Groove; 46. Second support part. Detailed Implementation

[0044] The specific embodiments of this utility model are described below with reference to the accompanying drawings.

[0045] Example 1:

[0046] like Figures 1-2 As shown, the small mold shell baking fixture suitable for the fast melting process in this embodiment includes a lower base 3, which includes a base body 32, a first insertion hole 33, a first support part 34 and a first channel 31.

[0047] A first insertion hole 33 is provided on the base body 32. One end of the first insertion hole 33 is a first socket, and the first insertion hole 33 communicates with the upper end surface of the base body 32 through the first socket. A first support part 34 is provided on the inner wall of the first insertion hole 33 for supporting the crucible 2 vertically below it. The product 1 is fixed at the upper end of the crucible 2 and is located above the first socket. A cavity 21 is provided inside the crucible 2. A first channel 31 is provided on the base body 32 and connects the first insertion hole 33 with the outside of the base body 32. When the crucible 2 is directly inserted into the first insertion hole 33, the lower end of the crucible 2 contacts the first support part 34. The inner diameter of the first insertion hole 33 is adapted to the diameter of the crucible 2, and the cavity 21 communicates with the first channel 31.

[0048] Specifically, product 1 is a component formed before the baking process, including a gate wax model, a part wax model connected to the upper end of crucible 2 in sequence, and a mold shell formed outside the wax model. After the wax model is baked away, the cavity of the mold shell is connected to the cavity 21. After the mold shell and crucible 2 are fully baked, a metal rod is placed in the cavity 21 of crucible 2, and a fast melting process can be carried out. After the metal rod is melted into molten steel, it is injected into the cavity of the mold shell.

[0049] In this embodiment of the calcination fixture, when the crucible 2 is directly inserted into the first insertion hole 33, the base body 32 is directly used to support the crucible 2. The first support part 34 plays a limiting role in the axial direction, and the inner wall of the first insertion hole 33 plays a limiting role in the radial direction, thereby ensuring that the product 1 and the crucible 2 are in an upright state.

[0050] The upward-facing insertion holes on conventional baking fixtures are blind holes, resulting in poor air permeability at the bottom of crucible 2 when positioning and supporting it. The mold shell used in the rapid melting process must be thoroughly baked to ensure good cleanliness before pouring molten steel, preventing inclusions and scrapping of the casting due to unburned residual organic matter. Furthermore, during the baking process, the organic binder used in the molding of crucible 2 needs to be fully baked; otherwise, black carbides will easily form, increasing the inclusion rate of the casting.

[0051] In this embodiment, the baking fixture has a first channel 31 on the base body 32. The first channel 31 is connected to the first insertion hole 33 for supporting and fixing the crucible 2, which facilitates the discharge and renewal of gas in the cavity 21 during the baking process, so that the product 1 (mold shell and wax mold) and the crucible 2 can be fully baked, reducing the inclusion rate of the casting.

[0052] When using the calcination fixture of this embodiment, the good air permeability of the fixture can be fully utilized to achieve complete calcination of product 1 without residue.

[0053] Product 1 includes a mold shell connected to crucible 2 and a wax mold located inside the mold shell. After firing, the cavity inside the mold shell is connected to the cavity 21.

[0054] like Figure 2 , Figure 6 As shown, the first channel 31 is arranged radially along the first insertion hole 33.

[0055] In one specific embodiment, the first support part 34 has a ring-shaped structure, and the first support part 34 has a notch at the position corresponding to the first channel 31. The first channel 31 is connected to the side wall of the first insertion hole 33 at the notch through the notch.

[0056] When there is only one first channel 31, there can be only one notch. A notch is provided on the first support part 34 to achieve good axial support for the first insertion hole 33. At the same time, the notch can introduce external gas into the side wall of the first insertion hole 33 through the radially arranged first channel 31. When the crucible 2 is directly inserted into the first insertion hole 33, the gas outside the end of the crucible 2 can also be updated in real time, so that the crucible 2 is roasted more fully.

[0057] In another specific implementation, such as Figure 2 , Figure 6 As shown, the first channel 31 extends along the axial direction of the first insertion hole 33 to the upper end face of the base body 32 and passes through the first insertion port.

[0058] When crucible 2 is directly inserted into the first insertion hole 33, there is also an airflow channel around crucible 2 along the axial direction, which makes crucible 2 more fully roasted and also increases the path of gas flow.

[0059] The number of first channels 31 is multiple, and they are evenly distributed in an array with the axis of the first socket 33 as the center.

[0060] Multiple first channels 31 are set with the axis of the first insertion hole 33 as the center, and the first channels 31 penetrate the upper end face of the base body 32 along the axial direction, so that the inner wall of the first insertion hole 33 is uniformly connected with the outside world, and multiple airflow channels are uniformly introduced to ensure that the product 1 and the crucible 2 are heated evenly.

[0061] like Figure 6 As shown, the first support part 34 is block-shaped, and there are multiple of them. They are spaced apart along the circumferential direction of the inner wall of the first insertion hole 33, and each first channel 31 is located between two adjacent first support parts 34.

[0062] Specifically, each first support part 34 is block-shaped and protrudes from the inner wall of the first insertion hole 33. The spaced first support parts 34 achieve good communication between the lower end face and outer peripheral surface of the crucible 2 and the first channel 31.

[0063] The calcination fixture of this embodiment is suitable for calcining small mold shells. For small mold shells for casting turbocharger turbines, the diameter ranges from 150mm to 40mm. The diameter of the matching crucible 2 varies greatly. The base body 32 can be replaced according to the crucible 2 of different sizes so that the diameter of the first insertion hole 33 and the support area of ​​the first support part 34 can be adapted to the crucible 2.

[0064] Example 2:

[0065] To improve the ease of use of the calcining fixture while ensuring complete calcination of both product 1 and crucible 2, the calcining fixture in this embodiment is based on that in embodiment one, as follows: Figures 3-8As shown, it also includes an upper base 4, which includes a connecting shaft 44 and a second insertion hole 43.

[0066] The connecting shaft 44 has a first insertion hole 33 that is adapted to the diameter of the connecting shaft 44. A first support part 34 is used to support the connecting shaft 44 vertically from one end of the connecting shaft 44. A second insertion hole 43 is located at the center of the connecting shaft 44 and extends through both ends of the connecting shaft 44 along the axial direction. The second insertion hole 43 is adapted to the diameter of the crucible 2 and communicates with the first insertion hole 33. A second support part 46 is provided on the inner wall of the second insertion hole 43. The second support part 46 is used to support the lower end face of the crucible 2, so that the product 1 is located outside the second insertion hole 43. When the crucible 2 is directly inserted into the second insertion hole 43, the connecting shaft 44 is inserted into the first insertion hole 33, the lower end of the crucible 2 contacts the second support part 46, and the cavity 21 communicates with the first channel 31.

[0067] When a small crucible 2 needs to be fired, the connecting shaft 44 of the upper base 4 is inserted into the first insertion hole 33. The side wall of the first insertion hole 33 radially limits the connecting shaft 44 to ensure its upright position. Then, the combination of the crucible 2 and product 1 to be fired is inserted into the second insertion hole 43. The upper end of the second insertion hole 43 is the second insertion port, which is used to insert the crucible 2 into the second insertion hole 43. The second support part 46 limits the crucible 2 axially, and the inner wall of the second insertion hole 43 radially limits the crucible 2, thereby ensuring that product 1 and crucible 2 are in an upright position.

[0068] The connecting shaft 44 of the upper base 4 is directly inserted into the first insertion hole 33 of the lower base 3, so that the upper base 4 is mounted on the lower base 3 to reduce the size of the insertion hole that directly supports the crucible 2. At the same time, it ensures that the second insertion hole 43 of the upper base 4 is connected to the first channel 31, thereby ensuring that the cavity 21 of the crucible 2 is connected to the first channel 31. When both the product 1 and the crucible 2 can be fully roasted, the combined roasting fixture is adapted to the small-sized crucible 2, and the roasting fixture can be quickly changed without stopping the furnace.

[0069] The calcination fixture of this embodiment may include a lower base 3 and one or more upper bases 4, which can be used for crucibles 2 of different specifications. The choice of whether to use the upper base 4 and which specification of upper base 4 to use depends on the specifications of the crucible 2. The calcination fixture of this embodiment can be quickly changed, improving production efficiency, reducing waiting time during the changeover process, and reducing production costs.

[0070] For turbines ranging from 150mm to 40mm in size, crucible 2 comes in two sizes: DN50 and DN80, suitable for both large and small sizes of product 1. The DN80 crucible 2 is supported by a lower base 3, while the DN50 crucible 2 is supported by a combination of lower base 3 and upper base 4. Specifically, the lower base 3 can support two larger mold shell sizes, and together with the upper base 4, they form a modular firing fixture that can support smaller mold shell sizes.

[0071] After conventional roasting fixtures are used, the lower end of crucible 2 is prone to blackish-gray incomplete roasting. Moreover, changing the fixture is troublesome, requiring the entire piece to be removed and replaced with a new model of roasting fixture, which is not only time-consuming but also energy-intensive.

[0072] After the baking fixture in this embodiment is baked, there are no obvious traces of incomplete baking at the lower end of crucible 2, and the casting yield is significantly improved (the inclusion rate decreases by 3 percentage points). In addition, the baking fixture is easy and quick to change, reducing energy consumption.

[0073] In addition, a positioning hole 35 is provided on the lower base 3, and a positioning pin that is fixedly connected to the furnace platform of the roasting furnace can be used to cooperate with the positioning hole 35 to fix the lower base 3 on the furnace platform and fix the roasting position.

[0074] like Figures 3-5 As shown, the inner wall of the second insertion hole 43 is provided with a plurality of grooves 45. The plurality of grooves 45 are evenly distributed around the axis of the second insertion hole 43. The length direction of each groove 45 is arranged along the axial direction of the second insertion hole 43. One end of the groove 45 is located on the upper end face of the connecting shaft 44, and the other end of the groove 45 is in the same axial position as the support surface of the second support part 46.

[0075] For example, for a DN50 crucible 2, during roasting, the lower end of the crucible 2 inserted into the roasting fixture is prone to insufficient roasting. Multiple axial grooves 45 are set on the inner wall of the second insertion hole 43. The grooves 45 and the outer wall of the crucible 2 form a second channel. Since the crucible 2 is small in size and usually made of silicon aluminum fiber, the overall weight of the crucible 2 and product 1 is relatively light. There is also a gap between the lower end face of the crucible 2 and the second support part 46, which realizes the connection between the second channel and the cavity 21. The second channel provides good gas flow space for the outer wall and end of the crucible 2, realizing good gas flow and renewal, making the roasting effect of the crucible 2 more complete, and solving the problem of roasting residue at the lower end of the small crucible 2.

[0076] like Figures 3-5 , Figure 8As shown, an extension 42 is provided on one end of the connecting shaft 44 located outside the first insertion hole 33. An insertion part 41 is provided on the extension 42. The insertion part 41 is inserted into the base body 32 and is used to position the connecting shaft 44 in the circumferential direction along the inner wall of the first insertion hole 33.

[0077] When the first channel 31 extends axially along the first insertion hole 33 to the upper end face of the base body 32 and communicates with the first socket, the insertion part 41 is inserted into the first channel 31 axially along the first insertion hole 33. When there are multiple first channels 31, the number of insertion parts 41 is the same as the number of first channels 31, and the axial dimension of the insertion part 41 is smaller than the axial dimension of the first channel 31 to avoid blocking the first channel 31. Preferably, the axial dimension of the insertion part 41 is 1 / 3 to 2 / 3 of the axial dimension of the first channel 31.

[0078] In addition, the extension 42 does not contact the upper surface of the base body 32, making it easy to remove the upper base 4.

[0079] The roasting fixture in this embodiment, when in use:

[0080] Fix the lower base 3 to the furnace platform of the roasting furnace;

[0081] When roasting a large-sized product 1, the combination of crucible 2 and product 1, which is adapted to the size of the first insertion hole 33 and the first support part 34, is directly inserted into the first insertion hole 33.

[0082] When roasting a small-sized product 1, insert the connecting shaft 44, which has a second insertion hole 43 and a second support part 46 that are adapted to the size of the crucible 2 to be roasted, into the first insertion hole 33, quickly install the upper base 4, and then insert the combination of the crucible 2 and product 1 to be roasted into the second insertion hole 43.

[0083] The above description is an explanation of the present utility model and not a limitation thereof. The scope of the present utility model is defined by the claims. Within the protection scope of the present utility model, any form of modification may be made.

Claims

1. A small mold shell firing fixture suitable for rapid melting process, characterized in that: Includes a lower base (3), said lower base (3) comprising: Base body (32); A first socket (33) is provided on the base body (32). One end of the first socket (33) is a first socket. The first socket (33) is connected to the upper surface of the base body (32) through the first socket. The first support part (34) is provided on the inner wall of the first insertion hole (33) for supporting the crucible (2) vertically below the crucible (2). The product (1) is fixed at the upper end of the crucible (2). The product (1) is located above the first insertion hole. The crucible (2) has a cavity (21). A first channel (31) is provided on the base body (32), and the first channel (31) connects the first socket (33) to the outside of the base body (32); When the crucible (2) is directly inserted into the first insertion hole (33), the lower end of the crucible (2) contacts the first support part (34), the inner diameter of the first insertion hole (33) is adapted to the diameter of the crucible (2), and the cavity (21) is connected to the first channel (31).

2. The small mold shell firing fixture suitable for rapid melting process as described in claim 1, characterized in that: The first channel (31) is arranged radially along the first insertion hole (33).

3. The small mold shell firing fixture suitable for rapid melting process as described in claim 2, characterized in that: The first support part (34) has a ring-shaped structure. The first support part (34) has a notch at the position corresponding to the first channel (31). The first channel (31) is connected to the side wall of the first insertion hole (33) at the notch through the notch.

4. The small mold shell firing fixture suitable for rapid melting process as described in claim 2, characterized in that: The first channel (31) extends along the axial direction of the first insertion hole (33) to the upper end face of the base body (32) and passes through the first insertion hole.

5. The small mold shell firing fixture suitable for rapid melting process as described in claim 4, characterized in that: The number of the first channels (31) is multiple, and they are evenly distributed in an array with the axis of the first socket (33) as the center.

6. The small mold shell firing fixture suitable for rapid melting process as described in claim 5, characterized in that: The first support part (34) is block-shaped and there are multiple of them. They are spaced apart along the circumferential direction of the inner wall of the first insertion hole (33), and each first channel (31) is located between two adjacent first support parts (34).

7. The small mold shell firing fixture suitable for rapid melting process as described in claim 1, characterized in that: It also includes an upper base (4), which comprises: A connecting shaft (44), the first insertion hole (33) is adapted to the diameter of the connecting shaft (44), and the first support (34) is used to vertically support the connecting shaft (44) from one end of the connecting shaft (44); The second insertion hole (43) is located at the center of the connecting shaft (44) and extends through both ends of the connecting shaft (44) along the axial direction. The second insertion hole (43) is adapted to the diameter of the crucible (2) and communicates with the first insertion hole (33). The inner wall of the second insertion hole (43) is provided with a second support part (46). The second support part (46) is used to support the lower end face of the crucible (2) so that the product (1) is located outside the second insertion hole (43). When the crucible (2) is directly inserted into the second insertion hole (43), the connecting shaft (44) is inserted into the first insertion hole (33), the lower end of the crucible (2) contacts the second support part (46), and the cavity (21) communicates with the first channel (31).

8. The small mold shell firing fixture suitable for rapid melting process as described in claim 7, characterized in that: The inner wall of the second socket (43) is provided with a plurality of grooves (45). The plurality of grooves (45) are evenly distributed around the axis of the second socket (43). The length direction of each groove (45) is arranged along the axial direction of the second socket (43). One end of the groove (45) is located on the upper end face of the connecting shaft (44), and the other end of the groove (45) is in the same axial position as the support surface of the second support part (46).

9. The small mold shell firing fixture suitable for rapid melting process as described in claim 7, characterized in that: An extension (42) is provided on one end of the connecting shaft (44) located outside the first insertion hole (33). The extension (42) is provided with a plug (41), which is plugged into the base body (32) to position the connecting shaft (44) along the circumferential direction of the inner wall of the first insertion hole (33).

10. The small mold shell firing fixture suitable for rapid melting process as described in claim 1, characterized in that: The product (1) includes a mold shell connected to the crucible (2) and a wax mold located inside the mold shell. After firing, the cavity inside the mold shell is connected to the cavity (21).

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