阅读说明：本技术 一种v法铸造中砂箱防漏砂装置 (Sand leakage prevention device for sand box in V-process casting ) 是由 张得新 张得国 张峰 于 2021-07-23 设计创作，主要内容包括：本申请提供了一种V法铸造中砂箱防漏砂装置,包括上砂箱、上排气管、下砂箱、下排气管；利用40目～70目的上第一筛网包覆套设在上排气管上且下第一筛网包覆套设在下排气管上,构成了防止型砂进入上排气管中与下排气管中的第一道防砂结构；利用70目～100目的上第二筛网封盖上排气管的出气口且下第二筛网封盖下排气管的出气口,构成了防止型砂进入上砂箱与下砂箱的箱壁中的环形空腔中的第二道防砂结构；利用100目～150目的上第三筛网封盖上抽真空口的进气口且下第三筛网封盖下抽真空口的进气口,构成了防止型砂进入真空系统中的第三道防砂结构；有效地防止了漏砂事故的发生,保护了砂型与真空系统。(The application provides a sand leakage prevention device for a sand box in V-process casting, which comprises an upper sand box, an upper exhaust pipe, a lower sand box and a lower exhaust pipe; an upper first screen mesh of 40-70 meshes is used for covering and sleeving the upper exhaust pipe, and a lower first screen mesh is used for covering and sleeving the lower exhaust pipe, so that a first sand prevention structure for preventing the molding sand from entering the upper exhaust pipe and the lower exhaust pipe is formed; an upper second screen mesh with 70 meshes to 100 meshes is used for sealing an air outlet of the upper exhaust pipe, and a lower second screen mesh is used for sealing an air outlet of the lower exhaust pipe, so that a second sand prevention structure for preventing the molding sand from entering annular cavities in the box walls of the upper sand box and the lower sand box is formed; an upper third screen mesh with 100 meshes to 150 meshes is used for sealing an air inlet of the upper vacuumizing port, and a lower third screen mesh is used for sealing an air inlet of the lower vacuumizing port, so that a third sand control structure for preventing molding sand from entering a vacuum system is formed; effectively prevents the occurrence of sand leakage accidents and protects the sand mould and the vacuum system.)

1. The V-method casting medium sand box sand leakage prevention device is characterized by comprising an upper sand box, an upper exhaust pipe, a lower sand box, a lower exhaust pipe, an upper first screen, a lower first screen, an upper second screen, a lower second screen, an upper third screen and a lower third screen;

the box wall of the cope box is a hollow rectangular pipe formed by welding steel plates in a sealing way, an annular cavity in the box wall of the cope box forms an upper vacuum chamber, a plurality of upper exhaust pipes for vacuumizing and exhausting are arranged in the cope flask and are pre-embedded in a cope mold in the cope flask, the two ends of the upper exhaust pipe in the length direction are respectively inserted into the through holes on the two opposite inner diameter box walls of the cope box, the two ends of the upper exhaust pipe in the length direction are respectively welded with the through holes on the two opposite inner diameter box walls of the cope box in a sealing way, the tube cavity of the upper exhaust pipe is communicated with the annular cavity in the box wall of the cope box, the tube wall of the upper exhaust pipe is provided with a plurality of upper exhaust holes for vacuumizing and exhausting, an upper vacuum pumping port communicated with an air inlet of a vacuum pump is formed in the outer diameter box wall of the cope box;

the box wall of the drag box is a hollow rectangular pipe formed by welding steel plates in a sealing way, an annular cavity in the box wall of the drag box forms a lower vacuum chamber, a plurality of lower exhaust pipes for vacuumizing and exhausting are arranged in the lower sand box and are pre-embedded in a lower sand mold in the lower sand box, the two ends of the lower exhaust pipe in the length direction are respectively inserted into the through holes on the two opposite inner diameter box walls of the drag flask, the two ends of the lower exhaust pipe in the length direction are respectively welded with the through holes on the two opposite inner diameter box walls of the drag box in a sealing way, the tube cavity of the lower exhaust pipe is communicated with the annular cavity in the box wall of the drag box, the tube wall of the lower exhaust pipe is provided with a plurality of lower exhaust holes for vacuumizing and exhausting, a lower vacuum pumping port communicated with an air inlet of a vacuum pump is arranged on the outer diameter box wall of the lower sand box;

the mesh number of the upper first screen is 40-70 meshes, and the upper first screen is sleeved on the outer surface of the upper exhaust pipe in a covering manner to form an upper first sand prevention structure for preventing the molding sand from entering the upper exhaust pipe from the upper exhaust hole;

the mesh number of the lower first screen is 40-70 meshes, and the lower first screen is sheathed on the outer surface of the lower exhaust pipe in a covering manner so as to form a lower first sand control structure for preventing the molding sand from entering the lower exhaust pipe from the lower exhaust hole;

the mesh number of the upper second screen is 70-100 meshes, the upper second screen is positioned in an annular cavity in the box wall of the cope box, the upper second screen is arranged on the inner surface of the inner diameter box wall of the cope box, one upper second screen covers a pipe orifice at one end of the upper exhaust pipe, the other upper second screen covers a pipe orifice at the other end of the upper exhaust pipe, and an upper second sand prevention structure for preventing the molding sand from entering the annular cavity in the box wall of the cope box from the upper exhaust pipe is formed;

the mesh number of the lower second screen is 70-100 meshes, the lower second screen is positioned in an annular cavity in the box wall of the drag box, the lower second screen is arranged on the inner surface of the inner diameter box wall of the drag box, one lower second screen covers a pipe orifice at one end of the lower exhaust pipe, and the other lower second screen covers a pipe orifice at the other end of the lower exhaust pipe, so that a lower second sand control structure for preventing the molding sand from entering the annular cavity in the box wall of the drag box from the lower exhaust pipe is formed;

the mesh number of the upper third screen is 100-150 meshes, the upper third screen is positioned in an annular cavity in the box wall of the cope box, the upper third screen is arranged on the inner surface of the outer diameter box wall of the cope box, and the upper third screen covers the air inlet of the upper vacuum-pumping port so as to form an upper third sand-preventing structure for preventing the molding sand from entering a vacuum system from the upper vacuum-pumping port;

the mesh number of the lower third screen is 100-150 meshes, the lower third screen is positioned in an annular cavity in the box wall of the drag flask, the lower third screen is arranged on the inner surface of the outer diameter box wall of the drag flask, and the lower third screen covers the air inlet of the lower vacuum-pumping port so as to form a lower third sand-preventing structure for preventing the molding sand from entering the vacuum system from the lower vacuum-pumping port.

2. The sand leakage preventing device for the sand box in V-process casting according to claim 1, wherein the upper exhaust pipe is filled with shear fragments of an upper fourth screen, the mesh number of the upper fourth screen is 70-100 meshes, the length of the shear fragments of the upper fourth screen is less than or equal to the inner diameter of the upper exhaust pipe, and the width of the shear fragments of the upper fourth screen is less than or equal to the inner diameter of the upper exhaust pipe;

the lower exhaust pipe is filled with shearing fragments of a lower fourth screen, the mesh number of the lower fourth screen is 70-100 meshes, the length of the shearing fragments of the lower fourth screen is smaller than or equal to the inner diameter of the lower exhaust pipe, and the width of the shearing fragments of the lower fourth screen is smaller than or equal to the inner diameter of the lower exhaust pipe.

3. The device for preventing sand leakage of a drag box in V-process casting according to claim 1, wherein the annular cavity in the wall of the cope box is filled with the shear fragments of the fifth screen, the annular cavity in the wall of the drag box is filled with the shear fragments of the fifth screen, the mesh number of the fifth screen is 100-150, the length of the shear fragments of the fifth screen is 1-2 cm, and the width of the shear fragments of the fifth screen is 1-2 cm.

4. The sand leakage preventing device for the sand box in V-process casting according to claim 1, wherein the upper first screen, the lower first screen, the upper second screen, the lower second screen, the upper third screen and the lower third screen are all metal screens or synthetic fiber screens.

Technical Field

The invention relates to the technical field of V-method casting, in particular to a sand leakage prevention device for a sand box in V-method casting.

Background

The V-method casting adopts Vacuum forming, obtains the name of the word head V of the English Vacuum, and has the greatest advantage that the V-method casting is different from the traditional sand casting that no molding sand binder is used.

In V-method casting, the granularity of the used molding sand is very small, usually 0.5mm-1mm, and it is very difficult to drill exhaust holes with the aperture smaller than 0.5mm on the inner diameter box wall of the cope flask and the inner diameter box wall of the drag flask, so that the molding sand particles enter annular cavities in the box walls of the cope flask and the drag flask from the exhaust holes during vacuum pumping in the prior art and are pumped out by a vacuum pump through an upper vacuum pumping port and a lower vacuum pumping port, namely, a sand leakage accident is easy to occur in the prior art. The sand leakage accident occurs, and the main harm is caused: firstly, sand in a sand mold is gradually pumped away, the quantity of the sand in a sand box is gradually reduced, if the sand is light, a cavity is pumped out of the sand mold, and if the sand is heavy, the sand mold deforms or collapses and the like; secondly, the sand is pumped into a vacuum system comprising a vacuum pump, a vacuum valve and the like, and devices related to vacuum such as the vacuum pump, the vacuum valve and the like are relatively precise instruments and are relatively expensive, so the sand can damage the devices comprising the vacuum pump, the vacuum valve and the like, the more the sand enters the vacuum system, the greater the reduction of the vacuum pumping capacity of the vacuum system is, and the problems of reduction of vacuum in a sand box, fluctuation of vacuum and the like during vacuum pumping are further caused.

Therefore, it is an urgent technical problem for those skilled in the art to prevent sand leakage, protect the sand mold, and protect the vacuum system including the vacuum pump and the vacuum valve, so as to facilitate the normal and smooth casting by the V method.

Disclosure of Invention

The invention aims to provide a sand leakage prevention device for a sand box in V-process casting.

In order to solve the technical problems, the technical scheme provided by the invention is as follows:

a sand leakage prevention device for a V-method casting medium sand box comprises an upper sand box, an upper exhaust pipe, a lower sand box, a lower exhaust pipe, an upper first screen, a lower first screen, an upper second screen, a lower second screen, an upper third screen and a lower third screen;

the box wall of the cope box is a hollow rectangular pipe formed by welding steel plates in a sealing way, an annular cavity in the box wall of the cope box forms an upper vacuum chamber, a plurality of upper exhaust pipes for vacuumizing and exhausting are arranged in the cope flask and are pre-embedded in a cope mold in the cope flask, the two ends of the upper exhaust pipe in the length direction are respectively inserted into the through holes on the two opposite inner diameter box walls of the cope box, the two ends of the upper exhaust pipe in the length direction are respectively welded with the through holes on the two opposite inner diameter box walls of the cope box in a sealing way, the tube cavity of the upper exhaust pipe is communicated with the annular cavity in the box wall of the cope box, the tube wall of the upper exhaust pipe is provided with a plurality of upper exhaust holes for vacuumizing and exhausting, an upper vacuum pumping port communicated with an air inlet of a vacuum pump is formed in the outer diameter box wall of the cope box;

the box wall of the drag box is a hollow rectangular pipe formed by welding steel plates in a sealing way, an annular cavity in the box wall of the drag box forms a lower vacuum chamber, a plurality of lower exhaust pipes for vacuumizing and exhausting are arranged in the lower sand box and are pre-embedded in a lower sand mold in the lower sand box, the two ends of the lower exhaust pipe in the length direction are respectively inserted into the through holes on the two opposite inner diameter box walls of the drag flask, the two ends of the lower exhaust pipe in the length direction are respectively welded with the through holes on the two opposite inner diameter box walls of the drag box in a sealing way, the tube cavity of the lower exhaust pipe is communicated with the annular cavity in the box wall of the drag box, the tube wall of the lower exhaust pipe is provided with a plurality of lower exhaust holes for vacuumizing and exhausting, a lower vacuum pumping port communicated with an air inlet of a vacuum pump is arranged on the outer diameter box wall of the lower sand box;

the mesh number of the upper first screen is 40-70 meshes, and the upper first screen is sleeved on the outer surface of the upper exhaust pipe in a covering manner to form an upper first sand prevention structure for preventing the molding sand from entering the upper exhaust pipe from the upper exhaust hole;

the mesh number of the lower first screen is 40-70 meshes, and the lower first screen is sheathed on the outer surface of the lower exhaust pipe in a covering manner so as to form a lower first sand control structure for preventing the molding sand from entering the lower exhaust pipe from the lower exhaust hole;

the mesh number of the upper second screen is 70-100 meshes, the upper second screen is positioned in an annular cavity in the box wall of the cope box, the upper second screen is arranged on the inner surface of the inner diameter box wall of the cope box, one upper second screen covers a pipe orifice at one end of the upper exhaust pipe, the other upper second screen covers a pipe orifice at the other end of the upper exhaust pipe, and an upper second sand prevention structure for preventing the molding sand from entering the annular cavity in the box wall of the cope box from the upper exhaust pipe is formed;

the mesh number of the lower second screen is 70-100 meshes, the lower second screen is positioned in an annular cavity in the box wall of the drag box, the lower second screen is arranged on the inner surface of the inner diameter box wall of the drag box, one lower second screen covers a pipe orifice at one end of the lower exhaust pipe, and the other lower second screen covers a pipe orifice at the other end of the lower exhaust pipe, so that a lower second sand control structure for preventing the molding sand from entering the annular cavity in the box wall of the drag box from the lower exhaust pipe is formed;

the mesh number of the upper third screen is 100-150 meshes, the upper third screen is positioned in an annular cavity in the box wall of the cope box, the upper third screen is arranged on the inner surface of the outer diameter box wall of the cope box, and the upper third screen covers the air inlet of the upper vacuum-pumping port so as to form an upper third sand-preventing structure for preventing the molding sand from entering a vacuum system from the upper vacuum-pumping port;

the mesh number of the lower third screen is 100-150 meshes, the lower third screen is positioned in an annular cavity in the box wall of the drag flask, the lower third screen is arranged on the inner surface of the outer diameter box wall of the drag flask, and the lower third screen covers the air inlet of the lower vacuum-pumping port so as to form a lower third sand-preventing structure for preventing the molding sand from entering the vacuum system from the lower vacuum-pumping port.

Preferably, the upper exhaust pipe is filled with shear fragments of an upper fourth screen, the mesh number of the upper fourth screen is 70-100 meshes, the length of the shear fragments of the upper fourth screen is less than or equal to the inner diameter of the upper exhaust pipe, and the width of the shear fragments of the upper fourth screen is less than or equal to the inner diameter of the upper exhaust pipe;

the lower exhaust pipe is filled with shearing fragments of a lower fourth screen, the mesh number of the lower fourth screen is 70-100 meshes, the length of the shearing fragments of the lower fourth screen is smaller than or equal to the inner diameter of the lower exhaust pipe, and the width of the shearing fragments of the lower fourth screen is smaller than or equal to the inner diameter of the lower exhaust pipe.

Preferably, the annular cavity in the wall of the cope flask is filled with the shearing fragments of the fifth screen, the annular cavity in the wall of the drag flask is filled with the shearing fragments of the fifth screen, the mesh number of the fifth screen is 100-150 meshes, the length of the shearing fragments of the fifth screen is 1-2 cm, and the width of the shearing fragments of the fifth screen is 1-2 cm.

Preferably, the upper first screen, the lower first screen, the upper second screen, the lower second screen, the upper third screen and the lower third screen are all metal screens or synthetic fiber screens.

The application provides a sand leakage prevention device for a sand box in V-process casting, which comprises an upper sand box, an upper exhaust pipe, a lower sand box, a lower exhaust pipe, an upper first screen, a lower first screen, an upper second screen, a lower second screen, an upper third screen and a lower third screen;

the upper first screen is sleeved on the outer surface of the upper exhaust pipe in a covering manner, the lower first screen is used for covering the outer surface of the lower exhaust pipe in a covering manner, and the upper first screen and the lower first screen are 40-70 meshes of screens, so that a first sand control structure for preventing molding sand from entering the upper exhaust pipe from an upper exhaust hole and entering the lower exhaust pipe from a lower exhaust hole is formed;

the upper second screen is used for sealing the air outlet of the upper exhaust pipe, the lower second screen is used for sealing the air outlet of the lower exhaust pipe, and the upper second screen and the lower second screen are screens with 70-100 meshes, so that a second sand control structure for preventing molding sand from entering an annular cavity in the box wall of the upper sand box from the upper exhaust pipe and entering an annular cavity in the box wall of the lower sand box from the lower exhaust pipe is formed;

the upper third screen is used for sealing the air inlet of the upper vacuumizing port, the lower third screen is used for sealing the air inlet of the lower vacuumizing port, and the upper third screen and the lower third screen are 100-150 meshes of screens, so that a third sand prevention structure for preventing molding sand from entering a vacuum system from the upper vacuumizing port and the lower vacuumizing port is formed;

the inner diameters of the meshes of the upper first screen and the lower first screen of 40-70 meshes are smaller than the theoretical minimum value of the particle size of the molding sand, and the inner diameters of the meshes of the screens of the first sand control structure, the second sand control structure and the third sand control structure are gradually reduced, so that large-particle sand is prevented first, and then small-particle sand is prevented, the sand leakage accident is effectively prevented, the sand mold is effectively protected, cavities, sand mold deformation or box collapse and the like in the sand mold are prevented, a vacuum system comprising a vacuum pump, a vacuum valve and the like is further protected, the problems of vacuum reduction, vacuum fluctuation and the like in the sand mold during vacuumizing caused by pumping the sand into the vacuum system are prevented, and the normal and smooth V-method casting is remarkably facilitated.

Drawings

FIG. 1 is a schematic cross-sectional structural view of a sand leakage preventing device for a flask in V-process casting according to an embodiment of the present invention (in actual production, the thickness of a screen is very thin, but in FIG. 1, the thickness of the screen is intentionally enlarged for the purpose of clearly seeing the screen, and although the size ratio is not consistent, FIG. 1 is only a schematic structural view;

in the figure: 1 cope flask, 101 upper vent pipe, 102 upper first screen, 103 upper second screen, 104 upper third screen, 105 inner diameter wall of cope flask, 106 outer diameter wall of cope flask, 107 annular cavity in wall of cope flask, 108 upper vent hole, 109 upper vacuum-pumping port;

2 drag flask, 201 drain, 202 first screen, 203 second screen, 204 third screen, 205 drag flask inside diameter wall, 206 drag flask outside diameter wall, 207 drag flask wall ring cavity, 208 drain, 209 drain.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.

In describing the present invention, it is to be understood that the terms "central," "axial," "radial," "longitudinal," "transverse," "length," "width," "upper," "lower," "front," "rear," "left," "right," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "vertical," "horizontal," and the like are used in the orientation or positional relationship indicated in the drawings for ease of description and simplicity of description, and do not indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and are not to be considered as limiting.

In the present invention, unless otherwise expressly stated or limited, the first feature being "on" or "under" the second feature may comprise the first feature being in direct contact with the second feature, or the first feature and the second feature being in direct contact with each other but being in contact with each other via another feature therebetween. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly above and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.

Referring to fig. 1, in the figure: a cope flask 1, an upper vent pipe 101, an upper first screen 102, an upper second screen 103, an upper third screen 104, an inner diameter wall 105 of the cope flask 1, an outer diameter wall 106 of the cope flask 1, an annular cavity 107 in the wall of the cope flask 1, an upper vent hole 108, an upper vacuum port 109; a drag flask 2, a lower vent pipe 201, a lower first screen 202, a lower second screen 203, a lower third screen 204, an inner diameter wall 205 of the drag flask 2, an outer diameter wall 206 of the drag flask 2, an annular cavity 207 in the wall of the drag flask 2, a lower vent hole 208, and a lower vacuum port 209.

The application provides a sand leakage prevention device for a V-method casting medium flask, which comprises a cope flask 1, an upper exhaust pipe 101, a drag flask 2, a lower exhaust pipe 201, an upper first screen 102, a lower first screen 202, an upper second screen 103, a lower second screen 203, an upper third screen 104 and a lower third screen 204;

the box wall of the cope box is a hollow rectangular pipe formed by welding steel plates in a sealing way, an annular cavity in the box wall of the cope box forms an upper vacuum chamber, a plurality of upper exhaust pipes 101 for vacuumizing and exhausting are arranged in the cope flask 1, the plurality of upper exhaust pipes 101 are pre-embedded in a cope mold in the cope flask 1, the two ends of the upper exhaust pipe 101 in the length direction are respectively inserted into the through holes on the two opposite inner diameter box walls of the cope flask 1, the two ends of the upper exhaust pipe 101 in the length direction are respectively welded with the through holes on the two opposite inner diameter box walls of the cope flask 1 in a sealing way, the lumen of the upper vent pipe 101 communicates with an annular cavity 107 in the wall of the cope flask 1, the upper exhaust pipe 101 is provided with a plurality of upper exhaust holes 108 for vacuum exhaust, an upper vacuum-pumping port 109 which is communicated with an air inlet of a vacuum pump is arranged on the outer diameter box wall 106 of the cope box 1;

the box wall of the drag box is a hollow rectangular pipe formed by welding steel plates in a sealing way, an annular cavity in the box wall of the drag box forms a lower vacuum chamber, a plurality of lower exhaust pipes 201 for vacuumizing and exhausting are arranged in the drag flask 2, the plurality of lower exhaust pipes 201 are pre-embedded in a lower sand mold in the drag flask 2, the two ends of the lower exhaust pipe 201 in the length direction are respectively inserted into the through holes on the two opposite inner diameter box walls of the drag flask 2, the two ends of the lower exhaust pipe 201 in the length direction are respectively welded with the through holes on the two opposite inner diameter box walls of the drag flask 2 in a sealing way, the lumen of the lower vent pipe 201 communicates with an annular cavity 207 in the wall of the drag flask 2, the pipe wall of the lower exhaust pipe 201 is provided with a plurality of lower exhaust holes 208 for vacuum exhaust, a lower vacuum pumping port 209 communicated with an air inlet of a vacuum pump is arranged on the outer diameter box wall 206 of the drag flask 2;

the mesh number of the upper first screen 102 is 40-70 meshes, and the upper first screen 102 is sheathed on the outer surface of the upper exhaust pipe 101 in a covering manner so as to form an upper first sand control structure for preventing the molding sand from entering the upper exhaust pipe 101 from the upper exhaust hole 108;

the mesh number of the lower first screen 202 is 40-70 meshes, and the lower first screen 202 is sheathed on the outer surface of the lower exhaust pipe 201 in a covering manner so as to form a lower first sand control structure for preventing the molding sand from entering the lower exhaust pipe 201 from the lower exhaust hole 208;

the mesh number of the upper second screen mesh 103 is 70-100 meshes, the upper second screen mesh is positioned in an annular cavity in the wall of the cope flask, the upper second screen mesh 103 is arranged on the inner surface of the inner diameter wall 105 of the cope flask 1, one upper second screen mesh 103 covers a nozzle at one end of the upper exhaust pipe 101, and the other upper second screen mesh 103 covers a nozzle at the other end of the upper exhaust pipe 101, so that an upper second sand control structure for preventing the molding sand from entering the annular cavity 107 in the wall of the cope flask 1 from the upper exhaust pipe 101 is formed;

the mesh number of the lower second screen mesh 203 is 70-100 meshes, the lower second screen mesh is positioned in an annular cavity in the box wall of the drag flask, the lower second screen mesh 203 is arranged on the inner surface of the inner diameter box wall 205 of the drag flask 2, one lower second screen mesh 203 covers a pipe orifice at one end of the lower exhaust pipe 201, and the other lower second screen mesh 203 covers a pipe orifice at the other end of the lower exhaust pipe 201, so that a lower second sand control structure for preventing the molding sand from entering the annular cavity 207 in the box wall of the drag flask 2 from the lower exhaust pipe 201 is formed;

the mesh number of the upper third screen 104 is 100-150 meshes, the upper third screen is positioned in an annular cavity in the box wall of the cope flask, the upper third screen 104 is arranged on the inner surface of the outer diameter box wall 106 of the cope flask 1, and the upper third screen 104 covers the air inlet of the upper vacuum-pumping port 109, so as to form an upper third sand-preventing structure for preventing the molding sand from entering a vacuum system from the upper vacuum-pumping port 109;

the mesh number of the lower third screen 204 is 100-150 meshes, the lower third screen is positioned in an annular cavity in the box wall of the drag flask, the lower third screen 204 is arranged on the inner surface of the outer diameter box wall 206 of the drag flask 2, and the lower third screen 204 covers the air inlet of the lower vacuum-pumping port 209, so that a lower third sand-preventing structure for preventing the molding sand from entering the vacuum system from the lower vacuum-pumping port 209 is formed.

In an embodiment of the present application, the upper exhaust pipe 101 is filled with shear fragments of an upper fourth screen, the mesh number of the upper fourth screen is 70-100 meshes, the length of the shear fragments of the upper fourth screen is less than or equal to the inner diameter of the upper exhaust pipe 101, and the width of the shear fragments of the upper fourth screen is less than or equal to the inner diameter of the upper exhaust pipe 101;

the lower exhaust pipe 201 is filled with shearing fragments of a lower fourth screen, the mesh number of the lower fourth screen is 70-100 meshes, the length of the shearing fragments of the lower fourth screen is less than or equal to the inner diameter of the lower exhaust pipe 201, and the width of the shearing fragments of the lower fourth screen is less than or equal to the inner diameter of the lower exhaust pipe 201;

preferably, the upper exhaust pipe 101 is a circular pipe, the cut pieces of the upper fourth screen are circular, and the outer diameter of the circular cut pieces of the upper fourth screen is equal to the inner diameter of the upper exhaust pipe 101;

preferably, the lower exhaust pipe 201 is a circular pipe, the shear fragments of the lower fourth screen are circular, and the outer diameter of the circular shear fragments of the lower fourth screen is equal to the inner diameter of the lower exhaust pipe 201;

the design is that the pipe cavity in the upper exhaust pipe 101 and the pipe cavity in the lower exhaust pipe 201 are fully and reasonably utilized, more screen meshes are arranged in the existing space of full utilization, the existing space is prevented from being wasted, the area of the screen meshes for sand control is increased, more layers of screen meshes are arranged, the number of layers of the screen meshes for sand control is increased, sand control is blocked as far as possible, sand leakage accidents are effectively prevented, sand molds are effectively protected, vacuum systems including a vacuum pump, a vacuum valve and the like are further protected, and the normal and smooth operation of V-method casting is remarkably facilitated.

In one embodiment of the present application, the annular cavity 107 in the wall of the cope flask 1 is filled with the shearing fragments of the fifth screen, the annular cavity 207 in the wall of the drag flask 2 is filled with the shearing fragments of the fifth screen, the mesh number of the fifth screen is 100-150, the length of the shearing fragments of the fifth screen is 1-2 cm, and the width of the shearing fragments of the fifth screen is 1-2 cm;

the design is that the annular cavity 107 in the box wall of the upper sand box 1 and the annular cavity 207 in the box wall of the lower sand box 2 are fully and reasonably utilized, more screens are arranged by fully utilizing the existing space, the waste of the existing space is avoided, the area of the screens for sand control is increased, more layers of screens are arranged, the number of layers of the screens for sand control is increased, the sand control of molding sand is blocked as far as possible, the sand leakage accident is effectively prevented, the sand mould is effectively protected, a vacuum system comprising a vacuum pump, a vacuum valve and the like is further protected, and the normal and smooth operation of V-process casting is remarkably facilitated.

In one embodiment of the present application, the upper first screen 102, the lower first screen 202, the upper second screen 103, the lower second screen 203, the upper third screen 104 and the lower third screen 204 are all metal screens or synthetic fiber screens.

In one embodiment of the present application, the upper fourth screen, the lower fourth screen and the fifth screen are all metal screens or synthetic fiber screens.

In the present application, the upper exhaust pipe 101 and the lower exhaust pipe 201 may be flexible pipes or metal hard pipes, such as steel pipes, which may be curved pipes or straight pipes, or may be multiple pipes; the number and distribution position of the upper exhaust pipes 101 cannot affect the arrangement of the upper sand molds, the sprue pipes, the riser pipes, etc. in the cope flask 1, but the number and distribution position of the lower exhaust pipes 201 cannot affect the arrangement of the lower sand molds, etc. in the drag flask 2.

The application provides a sand leakage prevention device for a sand box in V-process casting, which comprises an upper sand box 1, an upper exhaust pipe 101, a lower sand box 2, a lower exhaust pipe 201, an upper first screen mesh 102, a lower first screen mesh 202, an upper second screen mesh 103, a lower second screen mesh 203, an upper third screen mesh 104 and a lower third screen mesh 204;

in the present application, the upper first screen 102 is used to cover the outer surface of the upper exhaust pipe 101, and the lower first screen 202 is used to cover the outer surface of the lower exhaust pipe 201, because the upper first screen 102 and the lower first screen 202 are 40-70 mesh screens, a first sand control structure for preventing the molding sand from entering the upper exhaust pipe 101 from the upper exhaust hole 108 and entering the lower exhaust pipe 201 from the lower exhaust hole 208 is formed;

the air outlet of the upper exhaust pipe 101 is sealed by the upper second screen 103, the air outlet of the lower exhaust pipe 201 is sealed by the lower second screen 203, and the upper second screen 103 and the lower second screen 203 are screens with 70-100 meshes, so that a second sand control structure for preventing the molding sand from entering the annular cavity 107 in the wall of the cope flask 1 from the upper exhaust pipe 101 and entering the annular cavity 207 in the wall of the drag flask 2 from the lower exhaust pipe 201 is formed;

in the present application, the upper third screen 104 is used to cover the air inlet of the upper vacuum-pumping port 109, and the lower third screen 204 is used to cover the air inlet of the lower vacuum-pumping port 209, because the upper third screen 104 and the lower third screen 204 are 100-150 mesh screens, a third sand control structure for preventing the molding sand from entering the vacuum system from the upper vacuum-pumping port 109 and the lower vacuum-pumping port 209 is formed;

because the inner diameters of the meshes of the upper first screen 102 and the lower first screen 202 of 40-70 meshes are smaller than the theoretical minimum value of the particle size of the molding sand, and because the inner diameters of the meshes of the screens of the first sand control structure, the second sand control structure and the third sand control structure are gradually reduced, large-particle sand is prevented first, and then small-particle sand is prevented, so that sand leakage accidents are effectively prevented, the sand mold is effectively protected, cavities, sand mold deformation or crush and the like in the sand mold are prevented, a vacuum system comprising a vacuum pump, a vacuum valve and the like is further protected, the problems of vacuum reduction, vacuum fluctuation and the like in the sand mold during vacuumizing, caused by pumping the sand into the vacuum system, are prevented, and the normal and smooth V-method casting is remarkably facilitated.

The methods and apparatus described in this disclosure are not exhaustive of the prior art and are not described in detail.

The principles and embodiments of the present invention are explained herein using specific examples, which are presented only to assist in understanding the method and its core concepts of the present invention. It should be noted that, for those skilled in the art, it is possible to make various improvements and modifications to the present invention without departing from the principle of the present invention, and those improvements and modifications also fall within the scope of the claims of the present invention.