Gold type evanescent mode modeling method without exhaust risers

Abstract

The invention relates to the technical field of casting, in particular to an exhaust riser-free gold type evanescent mode modeling method which comprises the following steps: S1, treatment of the bottom surface of an evanescent mode model: before modeling, a slag discharge channel placement procedure is not reserved any more, and the bottom surface of a gold type evanescent mode is directly prepared; s2, sand box overturning operation: overturning the sand box; s3, air pipe arrangement, wherein an electric or pneumatic tool is used for punching; s4, mounting and sealing an air pipe: inserting one end of the air pipe into the bottom surface of the evanescent mode model, treating a gap between the air pipe and the model by using putty or a paper adhesive tape, and sealing the other end of the air pipe; and S5, post-treatment is conducted after modeling is completed, specifically, a slag discharging channel and an exhaust riser are not placed on the bottom face any more, and an air pipe channel is filled with molten iron after casting is completed. According to the invention, residual substances after foam combustion can be smoothly discharged out of the sand box, so that the risk that residues are generated on the surface of a casting is further reduced.

Description

Technical Field

[0001] The invention relates to the technical field of casting, in particular to a method for forming a lost foam mold without an exhaust riser. Background Art

[0002] Lost foam casting technology is an important casting process. It buries a foam model in a sand box and uses high-temperature molten iron to burn and gasify the foam model to form a casting. However, the traditional lost foam casting method usually requires a slag discharge channel and an exhaust riser at the bottom of the foam model to discharge the gas and residue produced by the foam combustion. These exhaust risers prevent gas accumulation, reduce air holding and box swelling during the casting process, but they have certain limitations. For example, in complex models, poor exhaust will still lead to defects in the casting, especially the residue after the foam combustion may adhere to the surface of the casting, affecting the quality of the casting.

[0003] In some cases, the existing exhaust riser design cannot effectively solve the problem of gas and residue emission, resulting in residual impurities on the surface of the casting, or casting defects caused by gas accumulation. With the complexity of the casting structure, traditional slag discharge channels and exhaust risers are difficult to adapt to diverse casting needs while ensuring the quality of the casting, especially in bottom castings. The arrangement of slag discharge channels and exhaust risers will not only affect the flexibility of the modeling, but also increase the production process and cost. Therefore, how to design a lost foam modeling method that does not rely on traditional exhaust risers to improve the casting quality and reduce the residue and defect problems in production has become a problem that needs to be solved urgently in the current technical field.

[0004] In order to solve the above problems, the present invention provides a lost foam molding method of a mold without exhaust risers, which avoids the casting defect problem caused by poor exhaust in the traditional method, and at the same time improves the production efficiency and the stability of quality control. Summary of the invention

[0005] The invention provides a method for forming a lost foam mold without exhaust risers.

[0006] A method for forming a lost foam mold without exhaust risers comprises the following steps:

[0007] S1, processing of the bottom surface of the lost foam model: before modeling, no slag channel placement process is reserved, and the bottom surface of the lost foam mold is directly prepared;

[0008] S2, sand box flipping operation: after completing the sand embedding molding on the front side of the main mold of the lost foam mold, flip the sand box;

[0009] S3, air pipe arrangement: use electric or pneumatic tools to punch holes on the boss plane, reinforcing ribs, and process ribs on the bottom surface of the lost foam mold;

[0010] S4, air pipe installation and sealing: insert one end of the air pipe into the bottom surface of the lost foam model, and use putty or paper tape to fix the gap between the air pipe and the model, and seal the other end;

[0011] S5, processing after molding is completed: no slag channel and exhaust riser are placed on the bottom surface, and the air pipe passage is filled with molten iron after the casting is completed.

[0012] Optionally, during the air pipe arrangement process, the punching depth and arrangement position are adjusted according to the shape and structure of the lost foam model.

[0013] Optionally, the material of the gas pipe burns rapidly when encountering the high temperature of molten iron, leaving only a gas passage.

[0014] Optionally, the depth of the holes punched in the trachea arrangement does not exceed 20 mm.

[0015] Optionally, the air pipe passage discharges residual substances after the foam is burned directly to the outside of the sand box.

[0016] Optionally, the air pipes are arranged with different lengths and densities according to different sizes and shapes of lost foam models.

[0017] Optionally, the arrangement and sealing of the air pipe ensure that defects will not occur in the bottom and structural parts of the casting due to untimely gas discharge.

[0018] Beneficial effects of the present invention:

[0019] The present invention eliminates the traditional slag discharge channel and exhaust riser structure through an innovatively designed exhaust-free riser molding method, and adopts an air pipe arrangement and sealing treatment method to ensure that the gas generated in the casting process can be discharged through the air pipe passage in time, effectively avoiding defects such as air holding and box swelling caused by gas accumulation in the casting. At the same time, through the arrangement of the air pipe and the selection of materials, the residual material after the foam combustion can be smoothly discharged outside the sand box, further reducing the risk of residue generation on the surface of the casting.

[0020] The present invention not only optimizes the gas exhaust efficiency through the uniform arrangement of the air pipes, but also can make the casting structure more complete through the filling effect of the air pipe passage, eliminating the possibility that the passage left by the air pipe affects the casting quality. The method is particularly suitable for lost foam castings with complex shapes, and can flexibly adjust the length and density of the air pipe according to the structure of different models to ensure the stability and reliability of the casting quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only for the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 A schematic diagram of a modeling method according to an embodiment of the present invention;

[0023] Figure 2 Schematic diagram of a general lost foam mold according to an embodiment of the present invention;

[0024] Figure 3 Schematic diagram of a modeling method according to an embodiment of the present invention. DETAILED DESCRIPTION

[0025] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. At the same time, it is explained here that in order to make the embodiments more detailed, the following embodiments are the best and preferred embodiments, and those skilled in the art may also adopt other alternatives to implement some known technologies; and the accompanying drawings are only for more specific description of the embodiments, and are not intended to specifically limit the present invention.

[0026] It should be noted that the references to "one embodiment", "an embodiment", "an exemplary embodiment", "some embodiments" and the like in the specification indicate that the embodiments described may include specific features, structures or characteristics, but not every embodiment may include the specific features, structures or characteristics. In addition, when a specific feature, structure or characteristic is described in conjunction with an embodiment, it should be within the knowledge of a person skilled in the art to implement such feature, structure or characteristic in conjunction with other embodiments (whether or not explicitly described).

[0027] In general, a term can be understood, at least in part, from its use in context. For example, depending, at least in part, on the context, the term "one or more" as used herein can be used to describe any feature, structure, or characteristic in the singular sense, or can be used to describe a combination of features, structures, or characteristics in the plural sense. Additionally, the term "based on" can be understood as not necessarily intended to convey an exclusive set of factors, but can instead, depending, at least in part, on the context, allow for the presence of other factors that are not necessarily explicitly described.

[0028] like Figure 1-Figure 3 As shown, a method for forming a lost foam mold without exhaust riser comprises the following steps:

[0029] 1. In the processes before molding, no slag channel placement process is reserved;

[0030] 2. After the front main mold of the gold mold is buried in sand, the sand box is turned over;

[0031] 3. After turning over, place the exhaust pipe on the bottom of the gold mold lost foam model, including:

[0032] Main positions: boss plane, reinforcement ribs, process scaffolding, etc.;

[0033] Placement method:

[0034] a. Use electric / pneumatic tools to drill holes evenly at the above positions, with a depth not exceeding 20mm;

[0035] b. Ensure that the air pipe is long enough to extend outside the sand box;

[0036] c. Insert one end of the air pipe into the bottom surface of the lost foam model, and use putty or paper tape to clean the gap between the air pipe and the model; seal the other end of the air pipe to prevent resin sand from entering and blocking the pipeline when the bottom surface is buried in sand;

[0037] d. There are no slag discharge channels or exhaust risers on the bottom surface.

[0038] Main functions:

[0039] 1. The air pipe will burn when it encounters the high temperature of molten iron. Only in the resin sand mold, the passage of the air pipe is retained. After the pouring is completed, the molten iron replaces the original passage, which will not cause the possibility of underfilling of the casting;

[0040] 2. The air pipe passages are evenly arranged on the bottom surface. During the pouring process, the generated gas can be discharged to the outside of the sand box in a timely and multiple places, eliminating the problems of suffocation and box expansion caused by gas accumulation;

[0041] 3. The air pipe passages are evenly arranged on the bottom surface. While exhausting the air, the residual substances after the foam combustion are also discharged directly to the outside of the sand box through the air pipes;

[0042] 4. The pouring personnel can judge whether the pouring is sufficient based on the molten iron situation at the air pipe of the sand box.

[0043] The present invention covers any substitution, modification, equivalent method and scheme made on the essence and scope of the present invention. In order to make the public have a thorough understanding of the present invention, specific details are described in detail in the following preferred embodiments of the present invention, but those skilled in the art can fully understand the present invention without the description of these details. In addition, in order to avoid unnecessary confusion about the essence of the present invention, well-known methods, processes, procedures, components and circuits are not described in detail.

[0044] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for forming a lost foam mold without exhaust riser, characterized in that: The following steps are involved: S1, processing of the bottom surface of the lost foam model: before modeling, no slag channel placement process is reserved, and the bottom surface of the lost foam mold is directly prepared; S2, sand box flipping operation: after completing the sand embedding molding on the front side of the main mold of the lost foam mold, flip the sand box; S3, air pipe arrangement: use electric or pneumatic tools to punch holes on the boss plane, reinforcing ribs, and process ribs on the bottom surface of the lost foam mold; S4, air pipe installation and sealing: insert one end of the air pipe into the bottom surface of the lost foam model, and use putty or paper tape to fix the gap between the air pipe and the model, and seal the other end; S5, processing after molding is completed: no slag channel and exhaust riser are placed on the bottom surface, and the air pipe passage is filled with molten iron after the casting is completed.

2. A method for forming lost foam molds without exhaust risers according to claim 1, characterized in that: During the air pipe arrangement process, the punching depth and arrangement position are adjusted according to the shape and structure of the lost foam model.

3. The method for forming a lost foam mold without exhaust riser according to claim 2, characterized in that: The material of the gas pipe burns rapidly when encountering the high temperature of molten iron, leaving only the passage of gas.

4. The method for forming a lost foam mold without exhaust riser according to claim 3, characterized in that: The depth of the holes punched in the trachea arrangement does not exceed 20 mm.

5. The method for forming a lost foam mold without exhaust riser according to claim 4, characterized in that: The air pipe passage discharges the residual materials after the foam is burned directly to the outside of the sand box.

6. The method for forming a lost foam mold without exhaust riser according to claim 5, characterized in that: The air pipes are arranged in different lengths and densities according to different lost foam model sizes and shapes.

7. A method for forming lost foam molds without exhaust risers according to claim 6, characterized in that: The arrangement and sealing of the air pipe ensure that defects will not occur at the bottom and structural parts of the casting due to untimely gas discharge.

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