TW202019580A - Precise casting process with a supporting step for shell mold recess placing a supporting member into the recess of the shell mold to reduce the occurrence of the mold swell - Google Patents

Abstract

The present invention is a precise casting process with a supporting step for shell mold recess, which comprises dipping the master mold, removing the master mold, supporting the recess of the shell mold, and casting, in which the shell mold has a recess. In the supporting step for the shell mold recess, a supporting member is placed into the recess of the shell mold. The supporting member is configured to provide support for the recess of the shell mold, which can make the recess of the shell mold sufficient to withstand thermal shock and pressure generated in the casting step and solve the problem of the mold swell while the recess of the shell mold is cast in the existing precision casting process. The present invention provides a precision casting process having the step of supporting the recess of the shell mold, which is capable of reducing the occurrence of the mold swell.

Description

Precise casting process with supporting steps of concave part of shell mold

This creation relates to casting, and in particular refers to a precision casting process with a step of supporting a concave part of a shell mold that can reduce the probability of expansion of the concave part of the shell mold during casting.

Traditional casting methods use metal, gypsum, ceramics, sand and other heat-resistant materials to make casting molds. Castings made by traditional casting methods have limited precision and usually have rough surfaces; they are different from traditional casting methods. Casting method, precision casting can be used to make parts with thin walls, complex contours, and precise dimensions; existing precision casting processes include: injection wax parts, repair wax parts, wax group trees, wax tree dip, shell mold dewaxing , Shell mold sintering, shell mold casting, shell mold cooling, shell mold shock shell, casting cutting, grinding gate, and related post-processing.

The existing precision casting process needs to comprehensively consider the shape and size of the castings to be produced when making shell molds and determining the number of waxing layers of the wax tree, as well as the shell molds required for shell mold dewaxing and shell mold casting steps The strength of the wax tree is generally about four to eight layers; however, as the size and weight of the casting increase, the thermal shock required by the shell mold and the pressure generated by the molten steel are also greater, when the molten steel conducts When the heat to the shell mold exceeds the limit value that the shell mold can withstand, the shell mold begins to soften and expands with the pressure generated by the molten steel to cause an expansion mold;

In order to avoid the expansion of the shell mold when casting molten steel, after the shell mold is sintered and before the molten steel is cast, the shell mold will be placed into the box first, and sand will be filled between the shell mold and the box , And then inject molten steel into the inside of the shell mold; however, as shown in FIGS. 9 and 10, a shell mold 70 is provided with a recess 71; a set of boxes 90 is provided with a box bottom 91; when the shell mold 70 is placed When entering the box 90, the concave portion 71 of the shell mold 70 faces the bottom 91 of the box 90 to form a space S, and sand is not easily filled in between the shell mold 70 and the box 90 Space S, so that the concave portion 71 can not be fully supported by the sand, and the molten steel will cause mold expansion;

Even if the steps of placing the shell mold 70 into the box and filling sand are omitted, the shell mold 70 is placed on the sand or refractory bricks, and then the molten steel is directly poured into the shell mold 70, the recess 71 The heat emitted from the place will still be collected in the space S, making the temperature of the recess 71 higher than the temperature of other parts of the shell mold 70, and it is also easy to exceed the thermal shock and pressure that the recess 71 can withstand, resulting in the expansion of the mold This happens; it can be seen that there is room for improvement and improvement in the existing precision casting process.

In order to solve the problem of the existing precision casting process, the concave part of the shell mold is easy to expand due to insufficient support or heat accumulation, this creation proposes a precision casting process, which includes the step of supporting the concave part of the shell mold Into the concave portion of the shell mold, the support member is pressed against the inner wall of the concave portion, which can provide support for the shell mold during the casting step, which can achieve the purpose of avoiding the mold expansion at the concave portion of the shell mold.

This invention creates a precision casting process with the support step of the concave part of the shell mold, which includes: 　　Sampling of the sample mold: immersing the same mold in the slurry to cover the slurry, and then carrying out sand staining, forming the slurry and sand coated on the sample mold A shell mold, wherein the shell mold includes more than one concave portion provided on the outer surface of the shell mold; 　　 sample mold removal: heating the sample mold together with the shell mold to melt the sample mold, leaving the shell mold ; 　　 shell mold concave support: place at least one support into at least one concave of the shell mold, so that the at least one support is supported against the at least one concave; 　　 casting: the molten steel is injected into the shell mold, the molten steel is cooled to form a casting ; And Demoulding: The casting is removed from the shell mold.

In the aforementioned precision casting process of the step of supporting the concave part of the shell mold, wherein each concave part of the shell mold includes a peripheral wall, in the step of supporting the concave part of the shell mold, a circumferential wall support is accommodated in the shell mold In one of the recesses, the peripheral wall support includes two opposite ends, and both ends of the peripheral wall support abut against the peripheral wall of the recess.

The aforementioned precision casting process of the step of supporting the concave part of the shell mold, wherein each concave part of the shell mold includes a bottom surface, and in the step of supporting the concave part of the shell mold, the concave part accommodating the peripheral wall support member is attached A bottom support member is further accommodated. The bottom support member includes a plane, and the plane of the bottom support member abuts against the bottom surface of the recess.

In the aforementioned precision casting process of the step of supporting the concave part of the shell mold, wherein each concave part of the shell mold includes a bottom surface, in the step of supporting the concave part of the shell mold, a bottom support member is accommodated in the shell mold A concave portion, the bottom support member includes a flat surface, and the flat surface of the bottom support member abuts against the bottom surface of the concave portion.

The above-mentioned precision casting process with the step of supporting the concave part of the shell mold, wherein a step of filling the box with sand is further arranged between the step of supporting the concave part of the shell mold and the casting step, which is to put the shell mold into a set And fill sand between the shell mold and the set of boxes.

The aforementioned precision casting process of the step of supporting the concave portion of the shell mold, wherein the step of supporting the concave portion of the shell mold is performed before the step of removing the sample mold.

The aforementioned precision casting process of the step of supporting the concave portion of the shell mold, wherein the step of supporting the concave portion of the shell mold is performed after the step of removing the sample mold.

In the aforementioned precision casting process of the step of supporting the concave portion of the shell mold, before the step of removing the sample mold, a shell mold sintering step is further arranged.

In the aforementioned precision casting process of the step of supporting the concave part of the shell mold, after the step of removing the sample mold, a shell mold sintering step is further arranged.

In the aforementioned precision casting process of the step of supporting the concave portion of the shell mold, at least one of the support members is made of refractory material.

The efficiency gains obtained by the technical means of this creation are: 　　 1. The precision casting process with the step of supporting the concave part of the shell mold in this creation is between the mold removal step and the casting step, or the sample film dipping step and Between the removal of the sample film, the step of supporting the concave part of the shell mold is added, and the support member is placed in the concave part of the shell mold to provide support, which can improve the quality of the casting. 2. In this creation, the precision casting process with the step of supporting the concave part of the shell mold is to support the concave part of the shell mold with the peripheral wall support. The peripheral wall support can provide support for the peripheral wall of the concave part, so that the peripheral wall of the concave part will not be cast. When the mold expansion occurs. 3. This creation uses a bottom support to support the concave part of the shell mold. The bottom support uses the set plane to provide support for the bottom surface of the concave part, so that the bottom surface of the concave part will not expand when casting. It also helps to improve the quality of castings.

In order to understand the technical features and practical effects of the present invention in detail, and can be implemented according to the content of creation, the preferred embodiments shown in the drawings are further described in detail below.

As shown in FIG. 1, the first preferred embodiment of the precision casting process with the step of supporting the concave part of the shell mold of the present invention is to perform the sample mold dipping slurry S1 after the sample mold, the repair sample mold, and the sample module tree are injected. Steps of removing S2, shell mold recess S3 and casting S4, and demolding.

Injection model: The model is made by pouring wax, plastic, mercury or foamed material. After the poured wax, plastic or mercury cools and solidifies to form the model, the model is taken out.

Refurbish the sample mold: remove the burrs of the sample mold or flatten the surface of the sample mold.

Sampling of sample mold S1: After lightly washing the surface of the sample mold, soak the sample mold in a slurry containing binder and refractory material to allow the slurry to adhere to the surface of the sample mold, and then carry out sand staining. The slurry and sand are dried to form a shell mold ; In the step of dip the slurry S1 of the model, soak the model repeatedly in the slurry and sand several times, in addition to uniformly attaching the slurry and sand to the surface of the model, and also allowing the shell mould to have sufficient thickness.

Sample mold removal S2: heating the sample mold together with the shell mold to melt the sample mold and flow out, and leaving the shell mold.

As shown in FIG. 2, a shell mold 10 includes an outer surface, a chamber 11 and a recess 12. The chamber 11 is provided inside the shell mold 10. The chamber 11 is used during the casting S4 step. For containing molten steel; the recessed portion 12 is recessed on the outer surface of the shell mold 10, and the recessed portion 12 includes a peripheral wall 121 and a bottom surface 122; in application, the contour of the shell mold 10 will be different according to different designs and even include There are a large number of the recesses 12, and the number and contour of the recesses 12 are not specifically limited in this creation.

Shell mold recessed portion support S3: In the step of shell mold recessed portion support S3, the peripheral wall 121 of the concave portion 12 of the shell mold 10 can be pressed against the support member.

As shown in FIG. 2, the peripheral wall support 20 is accommodated in the recess 12. The peripheral wall support 20 includes two opposite ends 21. Both ends 21 of the peripheral wall support 20 are fixed and abut against the recess 12 The peripheral wall 121, the peripheral wall support 20 can be made of refractory material with a refractoriness of 1100°C, but it is not limited to this; in application, the number of the peripheral wall support 20 can be set corresponding to the number of recesses 12, the The number of the peripheral wall supports 20 can also be set corresponding to the size of the concave portion 12, for example, a plurality of peripheral wall supports 20 are provided in the larger concave portion 12, so that the peripheral wall 121 of the concave portion 12 can be fully supported; The structure and shape of the peripheral wall support 20 are not particularly limited, as long as the peripheral wall support 20 can resist the peripheral wall 121 of the recess 12 and exert a supporting effect. The peripheral wall support 20 can even correspond to the contour of the recess 12 It is set to a plate shape, and the number, structure and shape of the peripheral wall support 20 are not specifically limited in this creation.

Casting S4: As shown in FIG. 3, molten steel is injected into the chamber 11 of the shell mold 10.

Demolding: After the molten steel is cooled, the casting is removed from the shell mold 10.

The precision casting process of the step of supporting the concave part of the shell mold of the present invention supports the circumferential wall 121 of the concave part 12 with the peripheral wall support 20. The peripheral wall support 20 can be the concave part of the shell mold 10 in the casting step S4 The peripheral wall 121 of 12 provides support. In addition to avoiding the deformation of the casting due to the expansion of the shell mold, it can also reduce the number of layers of slurry, reduce the manpower for performing the slurry operation, and shorten the time for the slurry operation. reduce manufacturing cost.

The second preferred embodiment of the precision casting process with the concave part supporting step of the shell mold created in this invention is substantially the same as the first preferred embodiment, as shown in FIGS. 4 and 5, the second preferred embodiment also includes a sample mold The steps of dip slurry S1, sample mold removal S2, shell mold concave support S3 and casting S4. The difference from the first preferred embodiment is that in the step S3 of supporting the concave part of the shell mold, a bottom support 30 is further placed into the concave part 12 and fixed with the peripheral wall 121 or the bottom surface 122 of the concave part 12, with the bottom The plane provided by the supporting member 30 supports the bottom surface 122 of the concave portion 12. The bottom supporting member 30 can be made of refractory material with a refractoriness of 1100° C., but it is not limited to this; The number, structure, and shape are also not particularly limited, as long as the flat surface of the bottom support 30 can resist the bottom surface 122 of the recess 12 to exert a supporting effect.

The third preferred embodiment of the precision casting process with the supporting step of the concave part of the shell mold created in this creation is shown in FIG. 6, FIG. 7 and FIG. 8. The third preferred embodiment mainly also includes a sample mold dipping slurry S1 and a sample mold release In addition to S2, shell mold concave support S3 and casting S4 steps. The third preferred implementation of this creation further arranges the box sand filling step between the shell mold concave support S3 and the casting S4 step: putting the shell mold 10 into the box and performing sand filling.

As shown in FIG. 6, the set of boxes 40 includes a box body 41; in the step S3 of the shell mold recessed portion of the third preferred embodiment of the present invention, the peripheral wall support 20 and the bottom support 30 are placed simultaneously The concave portion 12 of the shell mold 10, and the peripheral wall support 20 and the bottom support 30 respectively support the peripheral wall 121 of the concave portion 12 and the bottom surface 122 of the concave portion 12; The shell mold 10 is placed in the box body 41 of the box 40, and sand is filled between the shell mold 10 and the box body 41 of the box 40, except that the peripheral wall 121 and the peripheral wall 121 of the recess 12 of the shell mold 10 can be avoided The bottom surface 122 can support the other parts of the shell mold 10 by using the filled sand in addition to the expansion mold when molten steel is injected, which can further improve the casting quality.

In the first to third preferred embodiments of this creation, after the step S2 is removed from the sample, the step S3 is supported by the concave part of the shell mold; in application, it can also be applied before the step S2 is removed from the sample Place the peripheral wall support 20 or the bottom support 30 into the recess 12 to perform the shell mold recess support S3 step, as long as the shell mold recess support S3 step added in this creation can provide the shell when performing the casting S4 step The peripheral wall 121 and the bottom surface 122 of the concave portion 12 of the mold 10 are fully supported, and the expansion of the shell mold 10 can be avoided, which is the subject of protection for the creation.

Finally, the author can arrange the shell mold sintering step before the sample mold removal step S2 or after the sample mold removal step S2 to remove the moisture and other substances remaining in the shell mold 10 and improve the shell mold 10 Preferably, the shell mold 10 can be sintered after the peripheral wall support 20 and the bottom support 30 support the concave portion 12 of the shell mold 10 and before the step of boxing and sand filling. In order to avoid incomplete sintering of the shell mold.

S1: Prototype dip S2: Sample removal S3: Support of concave part of shell mold S4: casting 10: Shell mold 11: Room 12: recess 121: Perimeter wall 122: underside 20: Peripheral wall support 21: end 30: bottom support 40: set of boxes 41: cabinet 70: Shell mold 71: recess 90: set of boxes 91: bottom of the box S: Space

FIG. 1 is a flowchart of the first preferred embodiment of the present creation. FIG. 2 is an implementation schematic diagram of the first preferred embodiment of the present creation. FIG. 3 is an implementation schematic diagram of the first preferred embodiment of the present creation. FIG. 4 is an implementation schematic diagram of the second preferred embodiment of the present creation. FIG. 5 is an implementation schematic diagram of the second preferred embodiment of the present creation. FIG. 6 is an implementation schematic diagram of the third preferred embodiment of the present creation. FIG. 7 is an implementation schematic diagram of the third preferred embodiment of the present creation. FIG. 8 is an implementation schematic diagram of the third preferred embodiment of the present creation. 9 is a schematic diagram of the operation of the existing precision casting process. Figure 10 is a schematic diagram of the operation of the existing precision casting process.

S1: Prototype dip

S2: Sample removal

S3: Support of concave part of shell mold

S4: casting

Claims (10)

A precision casting process with the supporting step of the concave part of the shell mold, which includes: 　　 sample mold dipping slurry: the same mold is soaked in the slurry and covered with the slurry, and then the sand is dipped, and the slurry and the sand coated on the sample mold form a shell Mold, wherein the shell mold includes more than one concave portion provided on the outer surface of the shell mold; 　　 sample mold removal: heating the sample mold together with the shell mold to melt the sample mold, leaving the shell mold; 　　 shell Mold recess support: place at least one support into at least one recess of the shell mold to support the at least one support against the at least one recess; 　　casting: inject molten steel into the shell mold, and the molten steel is cooled to form a casting; and Demoulding: The casting is removed from the shell mold. The precision casting process with the step of supporting the concave portion of the shell mold according to claim 1, wherein each concave portion of the shell mold includes a peripheral wall, and in the step of supporting the concave portion of the shell mold, a peripheral wall support member is accommodated In one of the recesses of the shell mold, the peripheral wall support includes two opposite ends, and both ends of the peripheral wall support abut against the peripheral wall of the recess. The precision casting process with the step of supporting the concave part of the shell mold according to claim 2, wherein each concave part of the shell mold includes a bottom surface, and in the step of supporting the concave part of the shell mold, The concave portion of the member further accommodates a bottom support member. The bottom support member includes a flat surface, and the flat surface of the bottom support member abuts against the bottom surface of the concave portion. The precision casting process with the step of supporting the concave part of the shell mold according to claim 1, wherein each concave part of the shell mold includes a bottom surface, and in the step of supporting the concave part of the shell mold, a bottom support member is accommodated In one of the concave portions of the shell mold, the bottom support member includes a flat surface, and the flat surface of the bottom support member abuts against the bottom surface of the concave portion. 3 or 4 of the precision casting process with the step of supporting the concave part of the shell mold, wherein the step of filling the box with sand is further arranged between the step of supporting the concave part of the shell mold and the casting step, which is Place a set of boxes and fill sand between the shell mold and the set of boxes. The precision casting process with the step of supporting the concave part of the shell mold according to claim 5, wherein the step of supporting the concave part of the shell mold is performed before the step of removing the sample mold. The precision casting process with the step of supporting the concave part of the shell mold according to claim 5, wherein the step of supporting the concave part of the shell mold is performed after the step of removing the sample mold. According to the precision casting process of the step of supporting the concave portion of the shell mold as described in claim 5, a shell mold sintering step is further arranged before the sample mold removal step. According to the precision casting process of the step of supporting the concave portion of the shell mold as described in claim 5, after the step of removing the sample mold, a shell mold sintering step is further arranged. The precision casting process of the step of supporting a concave portion of a shell mold according to claim 1, wherein the at least one support member is made of refractory material.

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