CN112756557A - Atmospheric pressure spherical sand riser sleeve and manufacturing method thereof - Google Patents

Atmospheric pressure spherical sand riser sleeve and manufacturing method thereof Download PDF

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Publication number
CN112756557A
CN112756557A CN202011602193.XA CN202011602193A CN112756557A CN 112756557 A CN112756557 A CN 112756557A CN 202011602193 A CN202011602193 A CN 202011602193A CN 112756557 A CN112756557 A CN 112756557A
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CN
China
Prior art keywords
riser
sand
atmospheric pressure
sleeve
pressure spherical
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Pending
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CN202011602193.XA
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Chinese (zh)
Inventor
何媛
田鑫
戚梦林
苏少静
宋亮
纳建虹
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Kocel CSR Foundry Ltd
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Kocel CSR Foundry Ltd
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Priority to CN202011602193.XA priority Critical patent/CN112756557A/en
Publication of CN112756557A publication Critical patent/CN112756557A/en
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B22CASTING; POWDER METALLURGY
    • B22CFOUNDRY MOULDING
    • B22C9/00Moulds or cores; Moulding processes
    • B22C9/08Features with respect to supply of molten metal, e.g. ingates, circular gates, skim gates
    • B22C9/088Feeder heads

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Casting Devices For Molds (AREA)

Abstract

The invention relates to a riser sleeve, in particular to an atmospheric pressure spherical sand riser sleeve and a manufacturing method thereof. The utility model provides a spherical sand riser bush of atmospheric pressure, includes riser body and pinnacle sand, riser body lower extreme be provided with the riser neck that the riser body is linked together, just the riser body with form the stock solution chamber between the riser neck, the venthole with stock solution chamber intercommunication is seted up on the top of riser body, pinnacle sand set up in the inner chamber wall of riser body, the liquid outlet with stock solution chamber intercommunication is seted up to the bottom of riser neck, be provided with annular arch on the liquid outlet. The manufacturing method comprises the steps of parting the atmospheric pressure spherical sand riser sleeve; a snap fastener structure is arranged on the parting mould; and (5) molding and manufacturing by using a mold after parting. The invention overcomes the problem of low feeding efficiency of the open-top riser, obviously improves the feeding efficiency of the formed atmospheric pressure spherical riser, improves the process yield of castings, and reduces the sand-iron ratio and the production cost.

Description

Atmospheric pressure spherical sand riser sleeve and manufacturing method thereof
Technical Field
The invention relates to a riser sleeve, in particular to an atmospheric pressure spherical sand riser sleeve and a manufacturing method thereof.
Background
In the technological design of the gray iron casting, an open-top riser is usually selected for feeding, a cavity is formed in the open-top riser when a wood mold is molded, and the cavity is filled with molten iron during pouring to form the riser for feeding the casting. The top of the open top riser is exposed in the air, so the cooling speed is high and the feeding efficiency is low. In order to realize effective feeding of castings, a large-diameter high-height open top riser is required, molten iron used by the riser is high, so that the process yield is low, the height of a sand box is increased due to the high height required by the riser, the used molding sand is increased, the sand-iron ratio is increased, the process yield is low, and the sand-iron ratio is high, so that the production cost is high.
Disclosure of Invention
The invention aims to overcome the problem of low feeding efficiency of the open top riser and provide a novel atmospheric pressure spherical sand riser sleeve, the feeding efficiency of the formed atmospheric pressure spherical riser is obviously improved, the process yield of castings is improved, the sand-iron ratio is reduced, and the production cost is reduced.
The utility model provides a spherical sand riser bush of atmospheric pressure, includes riser body and pinnacle sand, riser body lower extreme be provided with the riser neck that the riser body is linked together, just the riser body with form the stock solution chamber between the riser neck, the venthole with stock solution chamber intercommunication is seted up on the top of riser body, pinnacle sand set up in the inner chamber wall of riser body, the liquid outlet with stock solution chamber intercommunication is seted up to the bottom of riser neck, be provided with annular arch on the liquid outlet.
In one embodiment, the main body of the atmospheric pressure spherical sand riser sleeve is a riser body, and the riser body is a spherical structural member.
In one embodiment, the pointed sand is positioned on the inner wall of the riser body of the atmospheric pressure spherical sand riser sleeve, the part contacting with the inner part of the riser body is thickest, and the inverted slope extends downwards and gradually narrows.
In one embodiment, the air outlet is positioned at the top end of the riser body and communicated with the liquid storage cavity.
In one embodiment, the riser neck is cylindrical and is connected to the lower portion of the riser body. The diameter of the riser is 0.3 to 0.5 times of the diameter of the riser.
In one embodiment, the annular projection is located at the lower end of the riser neck, and the width of the end of the annular projection away from the riser neck is gradually narrowed to form a bevel-shaped opening structure.
In one embodiment, the diameter of the smallest section of the annular protrusion is 0.25-0.35 times the diameter of the riser body.
Furthermore, the atmospheric pressure spherical sand riser sleeve is prepared from molding (core) sand, resin and a curing agent, and the thickness of the atmospheric pressure spherical sand riser sleeve is more than 20 mm.
Further, the spherical sand riser sleeve with high atmospheric pressure has the following manufacturing method:
parting the atmospheric pressure spherical sand riser sleeve;
a snap fastener structure is arranged on the parting mould;
and (5) molding and manufacturing by using a mold after parting.
In one embodiment, the atmospheric pressure spherical sand riser sleeve is formed by respectively forming an upper half and a lower half, parting is performed from the horizontal maximum diameter of the riser body, the atmospheric pressure spherical sand riser sleeve consists of an upper atmospheric pressure spherical sand riser sleeve and a lower atmospheric pressure spherical sand riser sleeve, and a snap fastener structure is arranged between the upper atmospheric pressure spherical sand riser sleeve and the lower atmospheric pressure spherical sand riser sleeve to form the atmospheric pressure spherical riser in a matching manner.
In one embodiment, the atmospheric pressure spherical sand riser sleeve is formed by respectively forming a left half and a right half, parting is performed from the vertical maximum diameter of the riser body, the atmospheric pressure spherical sand riser sleeve consists of a left atmospheric pressure spherical sand riser sleeve and a right atmospheric pressure spherical sand riser sleeve, and a snap-fit structure is arranged between the left atmospheric pressure spherical sand riser sleeve and the right atmospheric pressure spherical sand riser sleeve to form the atmospheric pressure spherical riser in a matching manner. The snap fastener structure is arranged to be a protruding structure and a pit structure on one side, the other side is arranged to be a pit structure and a protruding structure on the other side, and the left atmospheric pressure spherical sand riser sleeve and the right atmospheric pressure spherical sand riser sleeve are identical in structure.
In one embodiment, the atmospheric pressure spherical sand riser sleeve is integrally formed and can be realized by means of a 3D printing additive manufacturing technology.
The atmospheric pressure spherical riser formed by the atmospheric pressure spherical sand riser sleeve is a spherical blind riser with a conical groove and is communicated with the atmosphere, the feeding pressure in the riser is high, the feeding efficiency is obviously improved compared with that of an open top riser, and the feeding efficiency is improved to 15% from 8%. The riser sleeve can obviously improve the process yield and improve the process yield by 2 percent under the condition of meeting the feeding requirement of the gray iron castings.
The height of the atmospheric pressure spherical sand riser sleeve is reduced compared with that of an open top riser, the sand-iron ratio is also obviously reduced, and the sand-iron ratio is reduced by 0.5, so that the production cost is obviously reduced.
The annular bulge of the atmospheric pressure spherical riser formed by the atmospheric pressure spherical sand riser sleeve is easier to remove and clean than an open top riser, so that the cleaning cost is saved, the surface of a casting is not damaged, the mechanical damage rate of the casting is reduced, and the qualification rate of the casting is improved.
The manufacturing material of the atmospheric pressure spherical sand riser sleeve is completely the same as the molding (core) sand, and after the sand is boxed and shaked, the sand can enter the sand treatment and recovery system along with the molding (core) simultaneously, so that new impurities can not enter the molding (core) sand belt, and the purity of the reclaimed sand is more facilitated. The scheme of parting about the atmospheric pressure spherical sand riser bush can save mould expense, and especially core shooting machine mould is expensive, realizes that manufacturing cost practices thrift through practicing thrift mould expense, and only needs to deposit a riser bush, and a riser can all be constituteed to arbitrary two riser bushes, makes things convenient for the on-the-spot management to the riser bush.
Drawings
FIG. 1 is a cross-sectional view of an atmospheric pressure spherical sand riser sleeve;
FIG. 2 is a longitudinal sectional view of an atmospheric pressure spherical sand riser sleeve;
FIG. 3 is a schematic view of an atmospheric pressure spherical sand riser sleeve formed by upper and lower halves respectively;
FIG. 4 is a schematic view of an atmospheric pressure spherical sand riser sleeve formed by left and right halves;
FIG. 5 is a schematic view of the snap fastener of the riser bush formed by the left and right halves.
Wherein, the atmospheric pressure spherical sand riser sleeve-1, the pinnacle sand-2, the air outlet-3, the riser body-4, the riser neck-5, the annular bulge-6, the liquid storage cavity-11, the upper riser sleeve-7, the lower riser sleeve-8, the left riser sleeve-9, the right riser sleeve-10, the protruding structure 1-91, the pit structure 1-92, the pit structure 2-93 and the protruding structure 2-94
Detailed Description
In order to more clearly illustrate the technical solution of the present invention, the present invention is further described in detail with reference to the following specific examples. Note that the following described embodiments are illustrative only for explaining the present invention, and are not to be construed as limiting the present invention.
The first embodiment is as follows:
referring to fig. 1-2, an atmospheric pressure spherical sand riser sleeve 1 comprises a riser body 4 and pointed sand 2.
The main body of the atmospheric pressure spherical sand riser sleeve 1 is a riser body 4, and the riser body 4 is of a spherical structure. The heat mould number is maximum when the specific surface area of the sphere is minimum, the heat dissipation of the riser body is slow, the feeding efficiency is high, the casting with the same volume is fed, and the amount of molten iron needed by the spherical riser is minimum.
An air outlet hole 3 is arranged at the middle position of the top of the riser body 4. The air outlet 3 is a through cylindrical hole and mainly used for being communicated with the atmosphere and matched with the pinnacle sand 2 to form an atmospheric pressure riser, so that the feeding efficiency of the riser is improved, air in a cavity and the riser can be exhausted from the hole in the pouring process, and the phenomenon that the riser is not filled fully to cause the feeding to be influenced due to the fact that the top of the riser is blocked with air is avoided.
Meanwhile, the pointed top sand 2 is positioned at the top end inside the riser body 4 and symmetrically arranged at two sides of the air outlet hole 3. The part of the pinnacle sand 2 contacted with the riser body 4 is thickest and gradually narrowed to be narrower than 5mm when reaching the tip. When molten iron is filled into the center of the riser, a conical groove is formed at the top of the riser, so that the feeding pressure at the center of the riser is improved, and the riser becomes an atmospheric pressure riser.
The spherical riser with the atmospheric pressure is formed by the spherical sand riser sleeve with the atmospheric pressure, and the spherical blind riser with the conical groove is formed by the pointed top sand and is communicated with the atmosphere, so that the feeding pressure in the riser is high, and the feeding efficiency is obviously improved compared with that of an open top riser.
The lower end of the riser body 4 is provided with a riser neck 5 communicated with the riser body 4, and a liquid storage cavity 11 is formed between the riser body 4 and the riser neck 5. The liquid storage cavity 11 is communicated with the air outlet 3. The riser neck 5 is cylindrical and is connected with the lower part of the riser body 4, and the diameter of the riser neck is 0.3 times of that of the riser body 4, so that the riser is more beneficial to cleaning the riser.
The bottom of the riser neck 5 is provided with a liquid outlet communicated with the liquid storage cavity 11, and the liquid outlet is provided with an annular bulge 6.
The annular bulge 6 is located below the riser neck 5 and is of a slope-shaped opening structure after being formed, when risers are cleaned, the diameter of the minimum section of the annular bulge is 0.25-0.35 times of the diameter of the riser body, the risers are broken from the minimum section of the annular bulge 6, the rest slope-shaped openings close to the lower part are remained on the casting surface, the castings can be prevented from being damaged when being cleaned, and the risers can be removed, so that the risers can be easily removed and cleaned when the castings are not damaged. The slope-shaped opening structure remained on the surface of the casting can be removed by subsequent relief grinding.
The height of the atmospheric pressure spherical sand riser sleeve is reduced compared with that of an open top riser, the sand-iron ratio is also obviously reduced, and the sand-iron ratio is reduced by 0.5, so that the production cost is obviously reduced.
The annular bulge of the atmospheric pressure spherical riser formed by the atmospheric pressure spherical sand riser sleeve is easier to remove and clean than an open top riser, so that the cleaning cost is saved, the surface of a casting is not damaged, the mechanical damage rate of the casting is reduced, and the qualification rate of the casting is improved.
Example two:
a manufacturing method of an atmospheric pressure spherical sand riser sleeve is disclosed, as shown in figure 3, the atmospheric pressure spherical sand riser sleeve is formed in a mode that an upper half portion and a lower half portion are formed respectively, the upper half portion and the lower half portion are separated from the position of the maximum horizontal diameter of a riser body 4, the riser sleeve is composed of an upper riser sleeve 7 and a lower riser sleeve 8, and a snap fastener structure is arranged between the upper riser sleeve 7 and the lower riser sleeve 8 to form an atmospheric pressure spherical riser in a matched mode. The riser bush can be realized by means of manual molding or a core shooter, and two sets of molds are required for molding.
Example three:
a manufacturing method of an atmospheric pressure spherical sand riser sleeve is disclosed, and as shown in figure 4, the atmospheric pressure spherical sand riser sleeve is formed in a mode that a left half and a right half are formed respectively, the left half and the right half are formed in a parting mode from the position with the vertical maximum diameter of a riser body 4, the riser sleeve is composed of a left riser sleeve 9 and a right riser sleeve 10, and a snap fastener structure is arranged between the left riser sleeve 9 and the right riser sleeve 10 to form an atmospheric pressure spherical riser in a matched mode. The riser sleeve may be implemented by hand molding or core shooter. As shown in fig. 5, the snap fastener structure 91 of the riser bush 9 is a protruding structure 1, the snap fastener structure 92 is a recessed structure 1, the snap fastener structure 93 is a recessed structure 2, and the snap fastener structure 94 is a protruding structure 2, wherein the protruding structure 1 and the recessed structure 2 have the same shape and structure, so that the gap fit can be realized, and the recessed structure 1 and the protruding structure 2 have the same shape and structure, so that the gap fit can be realized. Due to the snap fastener design, the riser bush 9 and the riser bush 10 are completely the same and can be produced by one set of mould.
The scheme of left-right parting of the atmospheric pressure spherical sand riser sleeve in the second embodiment and the third embodiment has the advantages of simple manufacturing method and convenient operation. Meanwhile, the mould cost can be saved, the production cost is reduced, and a riser can be formed by any two riser sleeves, so that the riser is convenient to manage.
The atmospheric pressure spherical sand riser sleeve of example two and example three is prepared from molding (core) sand, resin and curing agent, and the thickness of the riser sleeve is more than 20 mm. The riser sleeve may also be implemented with 3D printing additive manufacturing techniques. The cost of the manufacturing material is low, and the sand can be recycled and regenerated along with a sand system. The manufacturing material of the atmospheric pressure spherical sand riser sleeve is completely the same as the molding (core) sand, and no new impurities are brought into the sand treatment and recovery system, so that the recovery effect of the recovered sand is good.
Although embodiments of the present invention have been shown and described, it is understood that the embodiments are illustrative and not restrictive, that various changes, modifications, substitutions and alterations may be made herein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims (10)

1. The atmospheric pressure spherical sand riser sleeve is characterized by comprising a riser body and pinnacle sand, wherein a riser neck communicated with the riser body is arranged at the lower end of the riser body, a liquid storage cavity is formed between the riser body and the riser neck, an air outlet communicated with the liquid storage cavity is formed in the top end of the riser body, the pinnacle sand is arranged on the inner cavity wall of the riser body, a liquid outlet communicated with the liquid storage cavity is formed in the bottom of the riser neck, and an annular bulge is arranged on the liquid outlet.
2. The atmospheric-pressure spherical sand riser sleeve as recited in claim 1, wherein the riser body is a spherical structural member.
3. The atmospheric-pressure spherical sand riser sleeve as defined in claim 1, wherein the peaked sand is symmetrically disposed on both sides of the air outlet hole.
4. The atmospheric-pressure spherical sand riser sleeve as defined in claim 3, wherein the apex sand gradually narrows in width in a direction from the outlet aperture toward the outlet port.
5. The atmospheric pressure spherical sand riser sleeve as defined in claim 1, wherein the riser neck has a diameter of 0.3 to 0.5 times the diameter of the riser body.
6. The atmospheric pressure spherical sand riser sleeve as defined in claim 1 wherein the annular projection has a tapered edge width at an end distal from the riser neck.
7. The atmospheric pressure spherical sand riser sleeve as defined in claim 6, wherein the annular protrusion has a minimum cross-sectional diameter of 0.25 to 0.35 times the riser body diameter.
8. A method of making an atmospheric pressure spherical sand riser sleeve as defined in claims 1-7, comprising the steps of:
parting the atmospheric pressure spherical sand riser sleeve;
a snap fastener structure is arranged on the parting mould;
and (5) molding and manufacturing by using a mold after parting.
9. The method of claim 8, wherein the step of parting is performed from a horizontal maximum diameter of the riser body or from a vertical maximum diameter of the riser body.
10. The method of making an atmospheric pressure spherical sand riser sleeve as recited in claim 9, wherein the atmospheric pressure spherical sand riser sleeve is made from a core sand, a resin, and a curing agent.
CN202011602193.XA 2020-12-31 2020-12-31 Atmospheric pressure spherical sand riser sleeve and manufacturing method thereof Pending CN112756557A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114406191A (en) * 2021-07-13 2022-04-29 芜湖格力精密制造有限公司 Sand casting structure, molding die and casting method

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2107622A (en) * 1982-09-17 1983-05-05 Foseco Int Riser sleeves
JPH11192535A (en) * 1997-10-28 1999-07-21 Hodogaya Ashland Kk Manufacture of sleeve for hot-top
JP2010042438A (en) * 2008-08-09 2010-02-25 Ie Solution Kk Riser and riser sleeve structure
CN102198489A (en) * 2011-05-13 2011-09-28 无锡小天鹅精密铸造有限公司 Insulation riser and moulding method thereof
CN204486707U (en) * 2015-02-05 2015-07-22 桐乡合德机械有限公司 Side exothermic riser neck
DE102015115437A1 (en) * 2015-09-14 2017-03-16 GTP Schäfer Gießtechnische Produkte GmbH Method for producing a feeder in a core shooter and core box suitable for carrying out the method
CN107433327A (en) * 2017-08-02 2017-12-05 共享装备股份有限公司 Inexpensive polystyrene spherical rising head and manufacture method
CN108772537A (en) * 2018-08-13 2018-11-09 共享装备股份有限公司 A kind of air buffer formula ball riser
CN110170616A (en) * 2019-05-30 2019-08-27 共享装备股份有限公司 Heat preservation riser and preparation method thereof

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2107622A (en) * 1982-09-17 1983-05-05 Foseco Int Riser sleeves
JPH11192535A (en) * 1997-10-28 1999-07-21 Hodogaya Ashland Kk Manufacture of sleeve for hot-top
JP2010042438A (en) * 2008-08-09 2010-02-25 Ie Solution Kk Riser and riser sleeve structure
CN102198489A (en) * 2011-05-13 2011-09-28 无锡小天鹅精密铸造有限公司 Insulation riser and moulding method thereof
CN204486707U (en) * 2015-02-05 2015-07-22 桐乡合德机械有限公司 Side exothermic riser neck
DE102015115437A1 (en) * 2015-09-14 2017-03-16 GTP Schäfer Gießtechnische Produkte GmbH Method for producing a feeder in a core shooter and core box suitable for carrying out the method
CN107433327A (en) * 2017-08-02 2017-12-05 共享装备股份有限公司 Inexpensive polystyrene spherical rising head and manufacture method
CN108772537A (en) * 2018-08-13 2018-11-09 共享装备股份有限公司 A kind of air buffer formula ball riser
CN110170616A (en) * 2019-05-30 2019-08-27 共享装备股份有限公司 Heat preservation riser and preparation method thereof

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袁修坪等: "造型线模具设计与制造", 《铸造设备与工艺》 *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114406191A (en) * 2021-07-13 2022-04-29 芜湖格力精密制造有限公司 Sand casting structure, molding die and casting method

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Application publication date: 20210507

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