CN216858172U

CN216858172U - Sand box pouring mold assembly structure using high-strength shell mold

Info

Publication number: CN216858172U
Application number: CN202123373278.8U
Authority: CN
Inventors: 刘德鑫
Original assignee: Heilongjiang Beifang Valve Co ltd
Current assignee: Heilongjiang Beifang Valve Co ltd
Priority date: 2021-12-31
Filing date: 2021-12-31
Publication date: 2022-07-01
Anticipated expiration: 2031-12-31

Abstract

A flask-casting mold assembly structure using a high-strength shell mold, comprising: the sand box comprises a sand box body, an upper shell mould, a lower shell mould, a pouring system, a riser and a buffer cushion, wherein the upper shell mould and the lower shell mould are high-strength shell moulds, the upper shell mould and the lower shell mould are combined and arranged in the sand box body up and down, a casting pouring cavity is formed in the combined body of the upper shell mould and the lower shell mould, the riser and the pouring system are arranged on the upper shell mould, the riser is communicated with the casting pouring cavity, the pouring system is used for communicating the casting pouring cavity to the outside of the sand box, the buffer cushion is arranged at the bottom of the sand box and supported at the lower part of the lower shell mould, and dry sand is filled in the space inside of the sand box and the space outside of the combined body of the upper shell mould and the lower shell mould.

Description

Sand box pouring mold assembly structure using high-strength shell mold

Technical Field

The utility model relates to a sand box pouring module structure, in particular to a sand box pouring module structure using a high-strength shell mold.

Background

The shell mold casting is a novel casting process method which is rapidly developed and popularized in recent years, the basic principle is that a casting cavity formed by combining a shell mold and a sand core is placed in a casting sand box, the fixing and heat conduction are realized by virtue of a filling medium, the operation of the casting process and the production quality of a casting are ensured, and the structural strength of the shell mold and the sand core is comprehensively considered, at present, resin sand mixed by resin binder and zircon sand is generally adopted as a core preparation raw material in actual production, because the resin binder is combusted in the casting process to generate a large amount of high-temperature gas to be timely led out, iron shots are required to be used as the filling medium in the sand box, the characteristics of good metal heat conductivity and large gaps among spheres are utilized to provide sufficient heat conductivity and gas permeability for the sand box, however, the iron shots are used as the filling medium, and the zircon sand is used as the core preparation raw material in the process method, the price of raw materials is high, so that the production cost is difficult to reduce all the time, more importantly, the gas evolution of resin sand casting is large, the combustion gas generated by the resin binder easily causes gas marks on the surface of a casting and even generates air holes in the casting, and the resin sand has the defect of poor deformability, so that the casting quality of the resin sand shell casting process is difficult to ensure fully, and the quality stability is not enough, meanwhile, the combustion gas of the resin binder also comprises a plurality of toxic and harmful gases, which pollute the workshop production environment and the atmospheric environment, in order to solve the problems, the shell casting process is improved, people begin to use the enhanced type sodium silicate sand instead of the resin sand as the preparation raw materials of the shell and the sand core, namely, the sodium silicate and the silica sand are used as raw materials, a proper amount of inorganic reinforcing agent is added to prepare the high-strength shell and the sand core, in order to improve the reliability of the high-strength sodium silicate shell casting process, the need exists for an improved sand box pouring and mold assembling structure which is matched with a high-strength shell mold casting process, so that the casting quality is improved, the production cost is reduced, and the environmental pollution is reduced.

SUMMERY OF THE UTILITY MODEL

The purpose of the utility model is: the sand box pouring and mold assembling structure using the high-strength shell mold is provided, and the reliability of the high-strength sodium silicate sand shell mold casting process is improved.

A flask-casting mold assembly structure using a high-strength shell mold, comprising: the casting sand comprises a sand box 1, an upper shell 2b, a lower shell 2a, a pouring system 4, a riser 5 and a buffer cushion 6, wherein the upper shell 2b and the lower shell 2a are high-strength shells and are vertically combined in the sand box 1, a casting pouring cavity is formed in a combination of the upper shell 2b and the lower shell 2a, the riser 5 and the pouring system 4 are installed on the upper shell 2b, the riser 5 is communicated with the casting pouring cavity, the pouring system 4 is used for communicating the casting pouring cavity to the outside of the sand box 1 and pouring molten liquid metal, the buffer cushion 6 is placed at the bottom of the sand box 1 and supported at the bottom of the lower shell 2a, and dry sand 10 is fully filled in the inside of the sand box 1 and the space outside of the combination of the upper shell 2b and the lower shell 2 a.

According to the process requirement of the casting structure, the sand box pouring module structure using the high-strength shell mold can further comprise a sand core 3, wherein the sand core 3 is arranged in the casting pouring cavity formed in the combined body formed by the upper shell mold 2b and the lower shell mold 2a, and forms the casting structure cavity together with the upper shell mold 2b and the lower shell mold 2 a.

Further, in the sand box pouring mold assembly structure using the high-strength shell mold, preferably, a gas guiding and exhausting hole 9 is formed in a box body of the sand box 1 and is used for being connected with a vacuum pump to guide and exhaust gas in the sand box 1 and the casting and pouring cavity, so that the sand box 1 forms a negative pressure state relative to an external space, and meanwhile, a flexible sealing film 7 covers the upper part of the sand box 1, so that a relatively closed space is formed inside the sand box 1.

In the flask pouring and molding structure using a high-strength shell mold, the upper shell mold 2b, the lower shell mold 2a, and the sand core 3 are preferably made of water glass sand added with a reinforcing agent, and the shell mold thickness of the upper shell mold 2b and the lower shell mold 2a is more preferably 20 to 30 mm.

The sand box pouring module structure using the high-strength shell mold has the following beneficial effects:

1. the high-strength shell type sodium silicate sand is adopted to replace resin sand, so that the sand cost can be effectively reduced, meanwhile, a resin binder is eliminated, the exhaust amount of combustion gas is reduced, the process requirements on heat conductivity and gas permeability of a filling medium of a sand box are reduced, the process feasibility is realized by replacing iron pills with dry sand, and the production cost can be further reduced;

2. the sodium silicate sand replaces resin sand to be used as a binder, so that the generation and discharge amount of toxic and harmful gases are greatly reduced, and meanwhile, the pouring is carried out in a negative pressure state, so that the generated waste gas can be collected and treated by a vacuum system, and the standard discharge is realized;

3. the negative pressure casting process ensures that the dry sand used as the filling medium of the sand box does not need to be added with a binder, the dry sand can be naturally scattered after the negative pressure is removed, and no sand falling and dust removal are needed, or the processing treatment is carried out by utilizing related regeneration equipment, so that the operation cost can be greatly reduced, and the labor intensity of workers is reduced;

4. the high-strength sodium silicate sand shell mold has almost no gas evolution in the casting process, so that the possibility of gas marks on the surface of a casting and gas holes in the casting is reduced, and meanwhile, the sodium silicate sand has good deformability and gas permeability, so that the occurrence tendency of casting defects such as casting wrinkles and shrinkage cavities can be effectively reduced, and the casting precision, the casting quality and the internal quality of the casting are improved;

5. by adopting the negative pressure casting process of pouring and cooling in the negative pressure state, the molten steel is always kept to have good fluidity and mold filling capacity, the problem of low casting compactness grade can be effectively solved, meanwhile, the hot cracking tendency of the casting can be effectively reduced, and the product quality of the casting is further improved.

Drawings

FIG. 1 is a schematic view showing the combination of a flask pouring group mold structure using a high-strength shell mold.

FIG. 2 is a schematic view showing a state of setting a lower shell mold in a flask pouring block structure using a high-strength shell mold.

Detailed Description

A sand box casting mold assembly structure for manufacturing a box product by using a high-strength shell mold is composed of a sand box 1, an upper shell mold 2b, a lower shell mold 2a, a sand core 3, a casting system 4, a riser 5, a cushion pad 6 and a flexible sealing film 7, as shown in figures 1 and 2.

The upper shell 2b, the lower shell 2a and the sand core 3 are prepared from sodium silicate sand added with a reinforcing agent, the shell thickness of the upper shell 2b and the lower shell 2a is 22 mm, the upper shell 2b, the lower shell 2a and the sand core 3 are matched to jointly form a casting structure cavity, the riser 5 and the pouring system 4 are installed on the upper shell 2b, the pouring system 4 is composed of a sprue gate and a sprue cup, the cushion pad 6 is supported at the bottom of the lower shell 2a, dry sand 10 is fully filled in the inner part of the sand box 1 and the outer space of the assembly of the upper shell 2b and the lower shell 2a, lifting columns 8 are correspondingly arranged on the symmetrical side surfaces of the sand box 1, gas guide and exhaust holes 9 are further formed in the box body, and the gas guide and exhaust holes 9 are formed in the lifting columns 8, the upper part is integrally covered with a flexible sealing film 7, and the flexible sealing film 7 is a plastic film.

The mould assembly and the application process of the sand box pouring mould assembly structure for manufacturing the box product by using the high-strength shell mould comprise the following steps:

step 1, preparing a sand box 1 on a casting mold assembly platform, and preparing a high-strength upper shell mold 2b, a high-strength lower shell mold 2a and a sand core 3 for later use;

step 2, uniformly placing the cushion pad 6 at the bottom in the sand box 1, placing the parting surface of the lower shell type 2a on the cushion pad 6, and enabling the cushion pad 6 to be supported at the bottom of the lower shell type 2a in a balanced and stable manner;

step 3, filling dry sand in a space below the parting surface of the lower shell mold 2a in the sand box 1 as shown in figure 2, and performing three-dimensional micro-vibration tamping;

step 4, placing the sand core 3 on the parting surface of the lower shell 2a, blowing floating sand in the cavity, coating a molding glue on the parting surface, aligning the upper shell 2b on the lower shell 2a, and pressing the upper shell 2b and the lower shell 2a tightly;

step 5, mounting a dead head 5 on the upper shell type 2b, and placing and bonding a sprue and auxiliary components;

step 6, continuously filling dry sand into the sand box 1 until the sand box 1 is completely filled, tamping the whole sand box 1 by three-dimensional micro vibration, scraping the dry sand on the top, paving a plastic film on the surface of the dry sand to form a relatively closed box body for the sand box 1, connecting a vacuum pump at the gas guide and exhaust hole 9, vacuumizing the sand box 1, and improving the compactness of the dry sand 10 filled in the sand box 1;

step 7, integrally transferring the sand box 1 to a pouring production line, placing and solidifying a pouring cup, laying an anti-scald felt on the plastic film, continuously keeping vacuumizing the sand box 1, and performing pouring operation in a vacuum state of a casting cavity;

and 8, keeping the casting to be cooled on the pouring production line, then closing the vacuum pump to remove vacuum, shakeout and taking out the casting, and directly taking dry sand into a recovery system for recycling.

Claims

1. A flask-casting mold assembly structure using a high-strength shell mold, comprising: a sand box (1), an upper shell type (2 b), a lower shell type (2 a), a pouring system (4), a riser (5) and a buffer pad (6), the upper shell (2 b) and the lower shell (2 a) are high-strength shells, are combined up and down and are arranged in the sand box (1), a casting pouring cavity is formed in the combination of the upper shell (2 b) and the lower shell (2 a), the riser (5) and the gating system (4) are arranged on the upper shell mold (2 b), the riser (5) is communicated with the casting pouring cavity, the pouring system (4) is used for communicating the casting pouring cavity to the outside of the sand box (1), the cushion pad (6) is placed at the bottom of the sand box (1) and supported at the bottom of the lower shell type (2 a), the inside of the flask (1) and the space outside the combination of the upper shell (2 b) and the lower shell (2 a) are filled with dry sand (10).

2. The flask-casting mold assembly structure of claim 1, wherein: the casting structure is characterized by further comprising a sand core (3), wherein the sand core (3) is arranged in the casting pouring cavity in the combined body formed by the upper shell mould (2 b) and the lower shell mould (2 a), and forms a casting structure cavity together with the upper shell mould (2 b) and the lower shell mould (2 a).

3. The flask-casting group mold structure using a high-strength shell mold according to claim 2, wherein: the air guide and exhaust hole (9) is formed in the box body of the sand box (1), and meanwhile, the flexible sealing film (7) covers the upper portion of the sand box (1), so that a relatively closed space is formed in the sand box (1).

4. A flask-casting pattern assembly structure using a high-strength shell mold according to claim 2 or 3, wherein: the upper shell mold (2 b), the lower shell mold (2 a) and the sand core (3) are prepared from water glass sand added with a reinforcing agent.

5. The flask-casting group mold structure using a high-strength shell mold according to claim 4, wherein: the shell thicknesses of the upper shell (2 b) and the lower shell (2 a) are 20-30 mm.