CN113996754A

CN113996754A - Casting sand mold and application thereof

Info

Publication number: CN113996754A
Application number: CN202111212994.XA
Authority: CN
Inventors: 何媛; 宋亮; 戚梦林; 刘利平; 宿飞
Original assignee: Kocel Machinery Co Ltd
Current assignee: Kocel Machinery Co Ltd
Priority date: 2021-10-22
Filing date: 2021-10-22
Publication date: 2022-02-01
Anticipated expiration: 2041-10-22
Also published as: CN113996754B

Abstract

The application relates to a casting sand mould, which comprises a sand mould body and a chilling part; the sand mold body comprises a casting cavity, an exhaust hole, an accommodating cavity and a supporting piece, wherein the exhaust hole is communicated with the casting cavity; an accommodating cavity matched with the chilling part is formed in one end, away from the casting cavity, of the exhaust hole; the bottom of the accommodating cavity is provided with a plurality of supporting pieces along the periphery of the exhaust hole, and the supporting pieces are used for supporting the chilling element; when the chilling part is placed in the containing cavity by the support part, a gap capable of discharging gas is formed between the chilling part and the containing cavity. The application also relates to a casting method, and the sand mould for casting is used. This application is through reasonable design, has both blockked impurities such as sand, the sediment of casting scene through chilling the piece and has fallen into the foundry goods die cavity, satisfies the exhaust demand of foundry goods die cavity when pouring through the exhaust hole again and hold the exhaust passageway that the clearance between chamber and the chilling between the piece formed.

Description

Casting sand mold and application thereof

Technical Field

The invention relates to the technical field of casting, in particular to a sand mould for casting and application thereof.

Background

In the casting process, when the metal liquid is filled in a casting cavity, the gas in the casting mold can be smoothly discharged to ensure that the metal liquid in the cavity can be stably and continuously filled, so that an exhaust structure is arranged at the top of the casting during the casting process design so as to discharge the gas in the cavity, and the defects of insufficient pouring, cold shut, choking air holes and the like caused by gas blocking are avoided. Generally, the exhaust structure of the casting cavity is an exhaust hole with a circular or rectangular cross section, the bottom end of the exhaust hole is communicated with the casting cavity, and the top end of the exhaust hole is communicated with the upper box surface of the sand mold.

Because the bottom end of the vent hole is communicated with the casting cavity, after pouring, the molten metal at the vent hole is connected with the upper surface of the casting, and the cross section of the vent hole is usually designed to be smaller in order to avoid causing too large contact thermal junctions. Meanwhile, in order to meet the requirement of exhaust volume, the number of the arranged exhaust holes is large, and the preorder modeling and the postorder cleaning are complex.

The top end of the exhaust hole is of an open structure, so that impurities such as sand, slag and the like in a casting site are easy to fall into a cavity, and the risk of the casting having the defects of sand inclusion, slag inclusion and the like is obviously increased; meanwhile, as the top end is of an opening structure, when the cavity and the vent holes are filled with molten metal, the molten metal easily flows out of the top of the vent holes and is paved on the upper box surface, the molten metal is seriously wasted, and inconvenience is caused to subsequent box beating and sand box cleaning.

Disclosure of Invention

Based on this, it is necessary to provide a casting sand mold which can avoid contacting a thermal node, prevent impurities from entering a casting cavity and save cost, aiming at the technical problems that the existing vent holes are small and many, the operation is complex, and the open structure at the top end of the vent hole causes sand inclusion and slag inclusion defects, and molten metal waste.

In order to solve the problems, the invention adopts the following technical scheme:

the embodiment of the invention discloses a casting sand mould, which comprises a sand mould body and a chilling part, wherein the sand mould body comprises a casting cavity, an exhaust hole, an accommodating cavity and a supporting part, and the exhaust hole is communicated with the casting cavity; an accommodating cavity matched with the chilling part is formed in one end, away from the casting cavity, of the exhaust hole; the bottom of the accommodating cavity is provided with a plurality of supporting pieces along the periphery of the exhaust hole, and the supporting pieces are used for supporting the chilling element; when the chilling part is placed in the containing cavity by the support part, an exhaust gap is formed between the chilling part and the containing cavity.

In one embodiment, the exhaust gap between the chilling part and the accommodating cavity is 3-5 mm.

In one embodiment, the cross-sectional area of the vent hole is 0.3-0.5 of the maximum cross-sectional area of the chilling element.

In one embodiment, the end of the chilling part at the bottom of the containing cavity is a cambered surface.

In one embodiment, the material of the chilling element is a metal material.

Preferably, the surface of the chilling element is coated with a refractory coating.

In one embodiment, when the chilling part is placed in the containing cavity (130), one end of the chilling part, which faces away from the exhaust hole, is higher than the containing cavity.

In one embodiment, the support follows the shape of the quench bottom.

In one embodiment, a groove is formed in the sand mold body along the periphery of the accommodating cavity on the side away from the casting cavity.

In a second aspect, the embodiment of the invention discloses an application method of the sand mould for casting; after the tank is closed, the chilling part is placed into the containing cavity; in the pouring process, when molten metal fills the casting cavity, gas in the casting cavity is discharged from the exhaust hole and a gap between the chilling part and the accommodating cavity; when the molten metal is filled to the bottom of the accommodating cavity, the molten metal enables the support member to be collapsed, and the support member loses the support effect on the chilling part; the chilling part sinks to plug the exhaust hole; the metal liquid which is filled between the chilling part and the containing cavity is chilled and solidified by the chilling part.

The technical scheme adopted by the invention can achieve the following beneficial effects:

according to the casting sand mold disclosed by the embodiment of the invention, after the casting cavity is cleaned by closing the box, the chilling part is placed in the containing cavity, so that impurities such as sand, slag and the like in a casting site are prevented from falling into the casting cavity, and the risk of casting defects such as sand inclusion, slag inclusion and the like generated in the casting process after the box is closed is reduced.

According to the casting sand mold disclosed by the embodiment of the invention, the gap between the chilling part and the containing cavity can meet the requirement of gas exhaust in the casting cavity in the process of filling the casting cavity; when the molten metal is filled to the bottom of the accommodating cavity, the molten metal wraps the support piece to enable the support piece made of resin sand to be collapsed, the support piece loses the supporting capacity for the chilling part, and the chilling part sinks under the action of gravity to seal the exhaust hole and prevent the molten metal from continuously flowing upwards; meanwhile, the thin-layer metal liquid which flows into the space between the chilling part and the containing cavity is chilled and solidified by the chilling part quickly, so that the metal liquid is further prevented from flowing upwards continuously, the waste of the metal liquid is avoided, and the cost is saved.

According to the casting sand mould disclosed by the embodiment of the invention, the chilling part prevents molten metal from spreading out of a box opening; even if the metal liquid filling speed is too high, partial metal liquid flows out of the accommodating cavity and also flows into the grooves arranged along the periphery of the accommodating cavity; avoid the adhesion of metal liquid and case area, solve because of the technical problem that the sand box area adhesion metal liquid leads to the sand box clearance difficulty.

According to the casting sand mould disclosed by the embodiment of the invention, the chilling element is contacted with the metal liquid filled in the exhaust hole to chill the metal liquid, so that the surface of the casting contacted with the exhaust hole is chilled, the contact thermal section of the exhaust hole to the casting is reduced, the size of the section of the exhaust hole can be increased compared with the prior art, the exhaust amount is met, the number of the exhaust holes is reduced, the field operation is simplified, and the production cost is saved.

According to the casting sand mold disclosed by the embodiment of the invention, the top end of the chilling part is higher than the containing cavity, the surface of the chilling part is coated with the refractory material, and the chilling part can be recycled after being boxed, so that the production cost is saved.

Drawings

FIG. 1 is a schematic structural view of a foundry sand mold disclosed in an embodiment of the present invention;

FIG. 2 is a schematic structural diagram of the sand mold body shown in FIG. 1;

FIG. 3 is a top view of FIG. 2;

fig. 4 is a cross-sectional view of the chilling element shown in fig. 1.

Description of reference numerals:

100-a sand mold body, 110-a casting mold cavity, 120-vent holes, 130-a containing cavity, 140-a supporting piece, 150-a groove and 200-a chilling piece.

Detailed Description

To facilitate an understanding of the invention, the invention will now be described more fully with reference to the accompanying drawings. Preferred embodiments of the present invention are shown in the drawings. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

In the description of the present invention, it should be noted that the terms "upper", "lower", "inner", "outer", "front", "rear", "both ends", "one end", "the other end", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "disposed," "connected," and the like are to be construed broadly, such as "connected," which may be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; the two elements may be directly connected or indirectly connected through an intermediate medium, or may be connected internally or indirectly. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

As shown in fig. 1 to 4, an embodiment of the present invention discloses a casting sand mold, which includes a sand mold body 100 and a chill 200; the sand mold body 100 includes a casting cavity 110, a vent hole 120, a receiving cavity 130, and a support 140. Specifically, the vent hole 120 is communicated with the casting cavity 130, and the accommodating cavity 130 is arranged at one end of the vent hole 120, which is far away from the casting cavity 110; the receiving cavity 130 is matched with the chilling element 200, and the chilling element 200 can be placed in the receiving cavity 130. The chilling element 200 is arranged in the containing cavity 130, so that sand dust and dust in the casting process are prevented from entering the casting cavity 110 through a channel formed by the containing cavity 130 and the exhaust hole 120, and casting defects are prevented from being formed.

The bottom of the accommodating cavity 130 is communicated with the exhaust hole 120, and the top of the accommodating cavity 130 is flush with one end of the sand mold body 100, which is far away from the casting cavity 110; the bottom of the receiving chamber 130 is provided with a plurality of supporters 140 along the circumference of the discharge hole 120. When the chilling element 200 is placed in the receiving chamber 130, the supporting member 140 at the bottom of the receiving chamber 130 functions to support the chilling element 200, so that a gap for exhausting gas is formed between the chilling element 200 and the receiving chamber 130.

In the embodiment of the invention, when the chilling part 200 is arranged in the containing cavity 130, the gap between the chilling part 200 and the containing cavity 130 is 3-5 mm, and the gap between the lower surface of the chilling part 200 and the exhaust hole 120 is 3-5 mm, so that gas in the casting cavity 110 can be smoothly exhausted when molten metal is filled in the casting process.

In the embodiment of the invention, the cross-sectional area of the exhaust hole 120 is 0.3-0.5 times of the maximum cross-sectional area of the chilling unit 200.

In the embodiment of the present invention, the main structure of the chilling element 200 is a cylinder, and the periphery of the cylinder has a slope, so that the chilling element 200 can be conveniently placed into and taken out of the accommodating cavity 130. The end of the chilling element 200 at the bottom of the accommodating cavity 130 is an arc surface, and of course, the bottom of the accommodating cavity 130 matched with the chilling element 200 is also an arc surface.

In the embodiment of the invention, the chilling element 200 is made of a metal material, is compact, has a certain weight, has excellent heat storage and heat transfer capacities, and can rapidly chill the molten metal.

Further, the surface of the quenching piece 200 is coated with a layer of refractory coating, so that subsequent cleaning and recycling are facilitated.

In the embodiment of the present invention, when the chilling element 200 is placed in the accommodating cavity 130, the chilling element 200 is higher than the top of the accommodating cavity 130, so as to facilitate the subsequent taking out and recycling of the chilling element 200. In addition, in the casting and mold filling processes, if the molten metal overflows the top of the accommodating cavity 130 before solidifying due to too high flowing speed of the molten metal, the molten metal does not wrap the chilling element 200 completely, and the chilling element 200 can be taken out for recycling by knocking the non-wrapped part.

Further, when the chilling element 200 is placed in the accommodating cavity 130, the chilling element 200 is 20-30 mm higher than the top of the accommodating cavity 130.

In the embodiment of the invention, the shape of the upper surface of the supporting member 140 and the bottom of the chilling element 200 is followed, so that the bearing capacity of the supporting member 140 on the chilling element 200 is increased; when the quench member 200 is placed in the containment chamber 130, the bottom of the quench member 200 seamlessly conforms to the upper surface of the support member 140.

In the embodiment of the present invention, a groove 150 is formed along the periphery of the accommodating cavity 130 on the side of the sand mold body 100 away from the casting cavity 110. In the casting and mold filling process, if the molten metal overflows the top of the accommodating cavity 130 before solidification because the flowing speed of the molten metal is too high, the overflowing molten metal flows into the groove 150, so that the adhesion of a molten metal paving box and a box belt is avoided, and the cleaning of a sand box is facilitated.

The embodiment of the invention also discloses a casting method, which uses the sand mould for casting in any embodiment.

The method specifically comprises the following steps:

and (4) designing a sand mould for casting by adopting simulation software.

The chill member 200 is prepared for use.

In the molding step, the sand mold body 100 having the casting cavity 110, the vent hole 120, the accommodating cavity 130 and the supporting member 140 is manufactured, and the molding process may be a 3D printing technique or a mold molding process, which is not specifically required in the embodiment of the present invention.

After the box is closed, the chilling element 200 is placed in the accommodating cavity 130, and due to the supporting effect of the supporting element 140 on the chilling element 200, a gap is formed between the chilling element 200 and the accommodating cavity 130. On one hand, due to the blocking effect of the chilling part 200, impurities such as sand, slag and the like on the casting site are prevented from falling into the casting cavity; on the other hand, the clearance between the chilling part 200 and the containing cavity 130 and the exhaust hole 120 form an exhaust channel to meet the exhaust requirement of gas in the casting cavity 110 during the mold filling process.

Pouring, when the casting cavity 110 is filled with molten metal, gas in the casting cavity 110 is exhausted from the exhaust holes and the gap between the chilling part 200 and the accommodating cavity 130; when the casting cavity 110 is filled with the molten metal, the molten metal continues to fill the vent hole 120, and when the molten metal is filled to the bottom of the accommodating cavity 130, the support 140 is wrapped by the molten metal, and the support 140 is collapsed by the molten metal at high temperature; the support 140 loses its holding capacity for the chill 200 and the chill 200 sinks under its own weight, plugging the vent 120. Meanwhile, the metal liquid filled between the chilling part 200 and the accommodating cavity 130 is chilled by the chilling part 200 and is rapidly solidified, so that the metal liquid is further prevented from continuously flowing upwards, and the waste of the metal liquid is avoided.

And (4) boxing, cleaning, recovering and recycling the chilling part.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. A foundry sand mould characterized by comprising a sand mould body (100) and a chill (200); the sand mold body (100) comprises a casting cavity (110), an exhaust hole (120), an accommodating cavity (130) and a support piece (140), wherein the exhaust hole (120) is communicated with the casting cavity (110); one end of the exhaust hole (120) departing from the casting cavity (110) is provided with an accommodating cavity (130) matched with the chilling part (200); the bottom of the accommodating cavity (130) is provided with a plurality of supporting pieces (140) along the periphery of the exhaust hole (120) for supporting the chilling element (200); when the support piece (140) enables the chilling part (200) to be placed in the containing cavity (130), an exhaust gap is formed between the chilling part (200) and the containing cavity (130).

2. The foundry sand mould of claim 1, wherein the vent gap between the chill (200) and the receiving cavity (130) is 3-5 mm.

3. The foundry sand mold of claim 1, wherein the cross-sectional area of the vent hole (120) is 0.3 to 0.5 times the maximum cross-sectional area of the chill (200).

4. Foundry sand mould according to claim 1, characterized in that the chill (200) is cambered at the bottom end of the receiving chamber (130).

5. The foundry sand mold of claim 1, wherein the material of the chilling member (200) is a metallic material.

6. Foundry sand mould according to claim 5, characterized in that the surface of the chill (200) is coated with a refractory coating.

7. Foundry sand mould according to claim 1, characterized in that the end of the chill member (200) facing away from the venting hole (120) is elevated above the receiving chamber (130) when the chill member (200) is placed in the receiving chamber (130).

8. A foundry sand mould according to claim 1, characterized in that the support member (140) is conformal with the bottom of the chill member (200).

9. Foundry sand mould according to claim 1, characterized in that the sand mould body (100) is provided with a recess (150) along the periphery of the receiving cavity (130) on the side facing away from the casting cavity (110).

10. A method of using a foundry sand mould according to any one of claims 1 to 9, characterized in that after mould assembling, the chill (200) is placed in the receiving chamber (130);

in the pouring process, when molten metal fills the casting cavity (110), gas in the casting cavity (110) is exhausted from the exhaust hole (120) and a gap between the chilling part (200) and the containing cavity (130); when the molten metal is filled to the bottom of the accommodating cavity (130), the molten metal enables the support (140) to be collapsed, and the support (140) loses the supporting effect on the chilling part (200); the chilling part (200) sinks to seal the exhaust hole (120).