阅读说明：本技术 一种大型箱体类部件覆膜砂铸造工艺 (Precoated sand casting process for large box parts ) 是由 袁纪飞 陆华 于 2020-12-09 设计创作，主要内容包括：本发明提供一种大型箱体类部件覆膜砂铸造工艺,涉及铸造工艺领域。该基于一种大型箱体类部件覆膜砂铸造工艺,包括以下步骤：S1：原料准备,将10-20kg覆膜砂倒入加热箱内部,通过加热箱内部的搅拌装置将覆膜砂快速搅拌,控制搅拌速度为50-60r/min,使得加热箱内部的温度控制在160-180摄氏度,搅拌时间控制在10-15分钟,然后静置；S2：制壳,将第一步当中处理之后的覆膜砂倒入壳体当中,在倒入壳体的时候,使得覆膜砂的温度不低于130摄氏度,然后通过液压装置将覆膜砂进行夹紧,控制压力为20-30Mpa,在压紧的过程中压力到达一定的范围的时候,然后使得压紧时间控制在10-20分钟,控制壳体的厚度为10-12毫米。极大地提高铸造工艺生产效率,降低了生产成本,质量更高。(The invention provides a precoated sand casting process for large box parts, and relates to the field of casting processes. The precoated sand casting process based on the large box part comprises the following steps: s1: preparing raw materials, pouring 10-20kg of precoated sand into a heating box, rapidly stirring the precoated sand by a stirring device in the heating box at a stirring speed of 50-60r/min, controlling the temperature in the heating box at 180 ℃, controlling the stirring time at 10-15 minutes, and then standing; s2: and (2) preparing a shell, pouring the precoated sand treated in the first step into the shell, wherein the temperature of the precoated sand is not lower than 130 ℃ when the precoated sand is poured into the shell, then clamping the precoated sand through a hydraulic device, controlling the pressure to be 20-30Mpa, controlling the compaction time to be 10-20 minutes when the pressure reaches a certain range in the compaction process, and controlling the thickness of the shell to be 10-12 millimeters. Greatly improves the production efficiency of the casting process, reduces the production cost and has higher quality.)

1. A precoated sand casting process for large box parts is characterized by comprising the following steps:

s1: raw material preparation

Pouring 10-20kg of precoated sand into a heating box, quickly stirring the precoated sand by a stirring device in the heating box at a stirring speed of 50-60r/min, controlling the temperature in the heating box at 180 ℃, controlling the stirring time at 10-15 minutes, and then standing;

s2: shell making

Pouring the precoated sand treated in the first step into a shell, wherein the temperature of the precoated sand is not lower than 130 ℃ when the precoated sand is poured into the shell, then clamping the precoated sand through a hydraulic device, controlling the pressure to be 20-30Mpa, controlling the pressing time to be 10-20 minutes when the pressure reaches a certain range in the pressing process, and controlling the thickness of the shell to be 10-12 millimeters;

s3: cooling down

Placing the manufactured shell into a cooling box, then controlling the internal radiating blades of the cooling box to enable the rotating speed of the blades to be 200-300r/min, and taking out the shell when the temperature of the shell is reduced to 10-15 ℃;

s4: assembly

Assembling the upper shell and the lower shell by an assembling process on a drawing;

s5: boxing

Filling iron sand outside the shell, compacting, sealing by adopting a plastic film, filling fine iron sand within the range of 10-15cm of the shell, filling coarse iron sand outside the shell by 15cm, and controlling the compaction degree of the fine iron sand and the coarse iron sand so that the compaction degree of each layer of fine iron sand and the coarse iron sand is uniform;

s6: pouring

Pouring molten iron into the inner cavity of the shell mold, cooling after pouring, molding a casting, controlling the pouring time to be 1-2min, leading generated waste gas into the waste gas treatment device through the gas outlet pipe in the pouring process, and leading waste heat in the waste gas to pass through the heat recycling device, so that the heat recycling device is arranged between the shell and the waste gas treatment device;

s7: unpacking box

When the temperature of the box body after pouring is reduced to be lower than 30 ℃, the box body is disassembled through a special disassembling tool, then the surface of the shell body after disassembling is polished through abrasive paper, surface impurities are removed, and the shell body can be obtained.

2. The precoated sand casting process for large box parts according to claim 1, wherein: the housing is adhesively attached at the gap after assembly using an adhesive material to prevent leakage of the high temperature liquid material.

3. The precoated sand casting process for large box parts according to claim 1, wherein: the shell is formed by closing an upper die and a lower die.

4. The precoated sand casting process for large box parts according to claim 1, wherein: the plastic film material used for boxing is high-strength polyethylene, and the thickness is 3-5 mm.

5. The precoated sand casting process for large box parts according to claim 1, wherein: the particle size of the fine iron sand is 0.5-0.8 mm.

6. The precoated sand casting process for large box parts according to claim 1, wherein: the grain size of the coarse iron sand is 1.2-1.5 mm.

7. The precoated sand casting process for large box parts according to claim 1, wherein: the heat recovery processing device can utilize the heat of the waste gas through heating circulation.

8. The precoated sand casting process for large box parts according to claim 1, wherein: the housing is vertically disposed within the box.

Technical Field

The invention relates to the technical field of casting technology, in particular to a precoated sand casting technology for large box parts.

Background

The precoated sand casting process is also called a "shell mold casting process" or a "heat hardening process". It is characterized in that: firstly, adopting precoated sand as a material, and manufacturing a shell mold by using a metal hot core box mold; the shape of a cavity arranged in the shell mold is the same as that of the casting, and the size of the cavity is the size allowance of the casting which is designed according to the material shrinkage ratio; then injecting high-temperature liquid materials such as molten iron and the like into the cavity, and cooling and solidifying to obtain the casting.

General precoated sand casting process is at the in-process of pouring, and the waste gas of production is directly handled through exhaust treatment device, but has certain heat in the middle of general waste gas, causes thermal waste, at the casted in-process, the concrete numerical value of accurate control compactedness for the casted box quality is low, so need a large-scale box class part precoated sand casting process now in order to overcome above problem

Disclosure of Invention

Technical problem to be solved

Aiming at the defects of the prior art, the invention provides a precoated sand casting process for large box parts, which solves the problems of high casting cost and waste gas utilization.

(II) technical scheme

In order to achieve the purpose, the invention is realized by the following technical scheme: a precoated sand casting process for large box parts comprises the following steps:

s1: raw material preparation

Pouring 10-20kg of precoated sand into a heating box, quickly stirring the precoated sand by a stirring device in the heating box at a stirring speed of 50-60r/min, controlling the temperature in the heating box at 180 ℃, controlling the stirring time at 10-15 minutes, and then standing;

s2: shell making

Pouring the precoated sand treated in the first step into a shell, wherein the temperature of the precoated sand is not lower than 130 ℃ when the precoated sand is poured into the shell, then clamping the precoated sand through a hydraulic device, controlling the pressure to be 20-30Mpa, controlling the pressing time to be 10-20 minutes when the pressure reaches a certain range in the pressing process, and controlling the thickness of the shell to be 10-12 millimeters;

s3: cooling down

Placing the manufactured shell into a cooling box, then controlling the internal radiating blades of the cooling box to enable the rotating speed of the blades to be 200-300r/min, and taking out the shell when the temperature of the shell is reduced to 10-15 ℃;

s4: assembly

Assembling the upper shell and the lower shell by an assembling process on a drawing;

s5: boxing

Filling iron sand outside the shell, compacting, sealing by adopting a plastic film, filling fine iron sand within the range of 10-15cm of the shell, filling coarse iron sand outside the shell by 15cm, and controlling the compaction degree of the fine iron sand and the coarse iron sand so that the compaction degree of each layer of fine iron sand and the coarse iron sand is uniform;

s6: pouring

Pouring molten iron into the inner cavity of the shell mold, cooling after pouring, molding a casting, controlling the pouring time to be 1-2min, leading generated waste gas into the waste gas treatment device through the gas outlet pipe in the pouring process, and leading waste heat in the waste gas to pass through the heat recycling device, so that the heat recycling device is arranged between the shell and the waste gas treatment device;

s7: unpacking box

When the temperature of the box body after pouring is reduced to be lower than 30 ℃, the box body is disassembled through a special disassembling tool, then the surface of the shell body after disassembling is polished through abrasive paper, surface impurities are removed, and the shell body can be obtained.

Preferably, the housing is adhesively attached at the gap after assembly using an adhesive material to prevent leakage of the high temperature liquid material.

Preferably, the housing is formed by closing two molds, namely an upper mold and a lower mold.

Preferably, the plastic film material used for boxing is high-strength polyethylene, and the thickness is 3-5 mm.

Preferably, the particle size of the fine iron sand is 0.5-0.8 mm.

Preferably, the particle size of the coarse iron sand is 1.2-1.5 mm.

Preferably, the heat recovery processing device can utilize the heat of the exhaust gas through a heating cycle.

Preferably, the housing is vertically disposed within the interior of the case.

(III) advantageous effects

The invention provides a precoated sand casting process for large box parts. The method has the following beneficial effects:

1. in the invention, the intensity and the rigidity of the precoated sand can be ensured by controlling the temperature in the heating box to be 160-180 ℃, the stirring time to be 10-15 minutes and the stirring speed of the stirring device to be 50-60 r/min.

2. According to the invention, when the shell is poured, the temperature of the precoated sand is not lower than 130 ℃, then the precoated sand is clamped by a hydraulic device, the pressure is controlled to be 20-30Mpa, when the pressure reaches a certain range in the pressing process, the pressing time is controlled to be 10-20 minutes, the thickness of the shell is controlled to be 10-12 millimeters, the quality of the shell can be higher, and the service life of the prepared shell is longer.

3. According to the invention, when the temperature of the shell is reduced to 10-15 ℃, the shell is taken out, so that the structure in the shell can reach a certain degree, and the integrity of the shell is more stable.

4. According to the invention, the fine iron sand is filled in the range of 10-15cm of the shell, the coarse iron sand is filled outside the shell by 15cm, and the compactness of the fine iron sand and the compactness of the coarse iron sand are controlled, so that the compactness of each layer of the fine iron sand and the compactness of the coarse iron sand are uniform, the generated heat can be rapidly dissipated into the fine iron sand and the coarse iron sand in the pouring process, the internal temperature of the shell can be rapidly reduced, and the shell has more perfect structural characteristics.

Detailed Description

The following will clearly and completely describe the technical solutions in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The first embodiment is as follows:

the embodiment of the invention provides a precoated sand casting process for large box parts, which comprises the following steps:

s1: raw material preparation

Pouring 10kg of precoated sand into a heating box, quickly stirring the precoated sand by a stirring device in the heating box at a stirring speed of 50r/min, controlling the temperature in the heating box to be 160 ℃, controlling the stirring time to be 10 minutes, and then standing;

s2: shell making

Pouring the precoated sand treated in the first step into a shell, wherein the temperature of the precoated sand is not lower than 130 ℃ when the precoated sand is poured into the shell, then clamping the precoated sand by a hydraulic device, controlling the pressure to be 20-30Mpa, controlling the pressing time to be 10-20 minutes when the pressure reaches a certain range in the pressing process, and controlling the thickness of the shell to be 10 mm;

s3: cooling down

Placing the manufactured shell into a cooling box, then controlling the internal radiating blades of the cooling box to enable the rotating speed of the blades to be 200-300r/min, and taking out the shell when the temperature of the shell is reduced to 10-15 ℃;

s4: assembly

Assembling the upper shell and the lower shell by an assembling process on a drawing;

s5: boxing

Filling iron sand outside the shell, compacting, sealing by adopting a plastic film, filling fine iron sand within the range of 10-15cm of the shell, filling coarse iron sand outside the shell by 15cm, and controlling the compaction degree of the fine iron sand and the coarse iron sand so that the compaction degree of each layer of fine iron sand and the coarse iron sand is uniform;

s6: pouring

Pouring molten iron into the inner cavity of the shell mold, cooling after pouring, molding a casting, controlling the pouring time to be 1-2min, leading generated waste gas into the waste gas treatment device through the gas outlet pipe in the pouring process, and leading waste heat in the waste gas to pass through the heat recycling device, so that the heat recycling device is arranged between the shell and the waste gas treatment device;

s7: unpacking box

When the temperature of the box body after pouring is reduced to be lower than 30 ℃, the box body is disassembled through a special disassembling tool, then the surface of the shell body after disassembling is polished through abrasive paper, surface impurities are removed, and the shell body can be obtained.

The housing is adhesively attached at the gap after assembly using an adhesive material to prevent leakage of the high temperature liquid material.

The shell is formed by closing an upper die and a lower die.

The plastic film material used for boxing is high-strength polyethylene, and the thickness is 3-5 mm.

The grain size of the fine iron sand is 0.5-0.8 mm.

The grain diameter of the coarse iron sand is 1.2-1.5 mm.

The heat recovery processing device can utilize the heat of the waste gas through heating circulation.

The housing is placed vertically inside the box.

Example two:

the embodiment of the invention provides a precoated sand casting process for large box parts, which comprises the following steps:

s1: raw material preparation

Pouring 20kg of precoated sand into a heating box, quickly stirring the precoated sand by a stirring device in the heating box, controlling the stirring speed to be 60r/min so that the temperature in the heating box is controlled to be 180 ℃, controlling the stirring time to be 15 minutes, and then standing;

s2: shell making

Pouring the precoated sand treated in the first step into a shell, wherein the temperature of the precoated sand is not lower than 130 ℃ when the precoated sand is poured into the shell, then clamping the precoated sand by a hydraulic device, controlling the pressure to be 20-30Mpa, controlling the pressing time to be 10-20 minutes when the pressure reaches a certain range in the pressing process, and controlling the thickness of the shell to be 12 millimeters;

s3: cooling down

Placing the manufactured shell into a cooling box, then controlling the internal radiating blades of the cooling box to enable the rotating speed of the blades to be 200-300r/min, and taking out the shell when the temperature of the shell is reduced to 10-15 ℃;

s4: assembly

Assembling the upper shell and the lower shell by an assembling process on a drawing;

s5: boxing

Filling iron sand outside the shell, compacting, sealing by adopting a plastic film, filling fine iron sand within the range of 10-15cm of the shell, filling coarse iron sand outside the shell by 15cm, and controlling the compaction degree of the fine iron sand and the coarse iron sand so that the compaction degree of each layer of fine iron sand and the coarse iron sand is uniform;

s6: pouring

Pouring molten iron into the inner cavity of the shell mold, cooling after pouring, molding a casting, controlling the pouring time to be 1-2min, leading generated waste gas into the waste gas treatment device through the gas outlet pipe in the pouring process, and leading waste heat in the waste gas to pass through the heat recycling device, so that the heat recycling device is arranged between the shell and the waste gas treatment device;

s7: unpacking box

When the temperature of the box body after pouring is reduced to be lower than 30 ℃, the box body is disassembled through a special disassembling tool, then the surface of the shell body after disassembling is polished through abrasive paper, surface impurities are removed, and the shell body can be obtained.

The housing is adhesively attached at the gap after assembly using an adhesive material to prevent leakage of the high temperature liquid material.

The shell is formed by closing an upper die and a lower die.

The plastic film material used for boxing is high-strength polyethylene, and the thickness is 3-5 mm.

The grain size of the fine iron sand is 0.5-0.8 mm.

The grain diameter of the coarse iron sand is 1.2-1.5 mm.

The heat recovery processing device can utilize the heat of the waste gas through heating circulation.

The housing is placed vertically inside the box.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.