US20080060778A1 - Binder composition and method of forming foundry sand cores and molds - Google Patents

Binder composition and method of forming foundry sand cores and molds Download PDF

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Publication number
US20080060778A1
US20080060778A1 US11/517,995 US51799506A US2008060778A1 US 20080060778 A1 US20080060778 A1 US 20080060778A1 US 51799506 A US51799506 A US 51799506A US 2008060778 A1 US2008060778 A1 US 2008060778A1
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United States
Prior art keywords
starch
sand
molds
cores
weight
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Abandoned
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US11/517,995
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English (en)
Inventor
Abraham Velasco-Tellez
Salvador Valtierra-Gallardo
Gilberto Garcia
Alberto Esquivel-Herrera
Satish Jhaveri
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Nemak SAB de CV
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Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
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Priority to US11/517,995 priority Critical patent/US20080060778A1/en
Assigned to TENEDORA NEMAK, S.A. DE C.V. reassignment TENEDORA NEMAK, S.A. DE C.V. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: ESQUIVEL-HERRERA, ALBERTO, GARCIA, GILBERTO, JHAVERI, SATISH, VALTIERRA-GALLARDO, SALVADOR, VELASCO-TELLEZ, ABRAHAM
Priority to EP07859284A priority patent/EP2107955A4/en
Priority to PCT/IB2007/004242 priority patent/WO2008029302A2/en
Priority to CA002662844A priority patent/CA2662844A1/en
Priority to US12/440,553 priority patent/US20110042028A1/en
Priority to MX2009002490A priority patent/MX2009002490A/es
Priority to ARP070103996A priority patent/AR062728A1/es
Publication of US20080060778A1 publication Critical patent/US20080060778A1/en
Assigned to TENEDORA NEMAK, S.A. DE C.V. reassignment TENEDORA NEMAK, S.A. DE C.V. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: ESQUIVEL-HERRERA, ALBERTO, GARCIA-TAPIA, GILBERTO, JHAVERI, SATISH, VALTIERRA-GALLARDO, SALVADOR, VELASCO-TELLEZ, ABRAHAM
Abandoned legal-status Critical Current

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22C—FOUNDRY MOULDING
    • B22C1/00—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds
    • B22C1/16—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds characterised by the use of binding agents; Mixtures of binding agents
    • B22C1/20—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds characterised by the use of binding agents; Mixtures of binding agents of organic agents
    • B22C1/26—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds characterised by the use of binding agents; Mixtures of binding agents of organic agents of carbohydrates; of distillation residues therefrom
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22C—FOUNDRY MOULDING
    • B22C1/00—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds
    • B22C1/16—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds characterised by the use of binding agents; Mixtures of binding agents
    • B22C1/18—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds characterised by the use of binding agents; Mixtures of binding agents of inorganic agents
    • B22C1/185—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds characterised by the use of binding agents; Mixtures of binding agents of inorganic agents containing phosphates, phosphoric acids or its derivatives

Definitions

  • the present invention refers to a binder and a method of forming foundry sand cores and molds, and more particularly to a water-based binder and a method of forming silica sand cores and molds with great economic and environmental advantages over the currently used organic-compound binders.
  • One of the preferred processes for manufacturing engine blocks and heads utilizes silica sand molds and cores.
  • the molds and cores are most typically made of silica sand grains bound by a heat-curable phenolic binder or a gas activated cold box binder.
  • the heat-curable binders have the disadvantage of requiring heat to set the molds and cores, producing foul-smelling vapors, and requiring special anti-pollution equipment to prevent ambient contamination.
  • Another disadvantage arises once the cast motor blocks or heads are solidified, since removal of such cores and molds needs additional heat to burn off the binder by contact with hot air (in order to combust the binder and thus loosen the sand to destroy the cores), thus adding further to the fuel cost of the process.
  • U.S. Pat. No. 2,508,359 discloses a starch-containing product for use as a core binder, and more particularly to such a binder made from dextrinized corn flour.
  • U.S. Pat. No. 5,582,231 discloses a foundry mold member made from a plurality of sand particles bound together with a binder which consists essentially of gelatins (animal protein). The sand particles are coated with a film of a binder of gelatin having Bloom ratings of less than about 175 Bloom grams.
  • the present invention provides a starch-based binder composition employable in the widely-used core forming process of blow boxes where it is desired to have a strong setting sand bonding agent and at the same time a sand mix that easily flows into the core molds and fills all the spaces in the geometries of even complex sand molds, such as for automotive parts.
  • the binder composition of the invention comprises specific additives which mixed with starch and sand are specially suited for such core making process.
  • Binder compositions discloses a binder composition consisting essentially of an aqueous solution of an alkali metal silicate and a stabilized starch hydrolysate having a dextrose equivalent of below 5. The components being present in the weight ratios, calculated as solids, of 0.4 to 35 parts of stabilized starch hydrolysate per 20 to 49.5 parts alkali metal silicate. The mixture is hardened either by gassing with carbon dioxide or by incorporating chemical hardening agents such as esters of polyhydric alcohols.
  • U.S. Pat. No. 4,158,574 “Hydrolyzed amylaceous product and process of making same” relates to a foundry binder system employing glyoxal, a polyhydroxyl compound and a unique catalyst comprised of inorganic alkali halides.
  • the polyols used are those that react rigidly with glyoxal including sugars, starch, starch hydrolysates, gums and dextrins.
  • the general object of the invention is to make it possible for glyoxal to be used as a low-cost resin-forming binder system with control over the rate of setting.
  • Applicants have found suitable additives for providing starch-based binder with sufficient fluidity for using the standard method of blowing sand cores while at then same time obtaining cores of sufficient strength and shape definition with the combination of additives in a predefined proportion thus providing a suitable core and mold making process at a competitive cost.
  • a binder made from starch having additives to improve flowability, to improve water repellency, and optionally to improve as needed the coating of the sand by the other additives by use of wetting agents.
  • silica sand with any kind starch can be a used to make sand cores for some limited foundry purposes. Even insoluble amylopectin can be used when a proper temperature is applied.
  • the sand mix can be dumped into any core box with most any geometry and compacted to make the desired cores.
  • the sand mix must be able to be blown into, and thereby be compacted in, the mold forms.
  • the coated sand typically is pushed through blow pipes of about 1 inch or less in diameter, using air pressure.
  • the applicants have been able to achieve this goal of using low cost water soluble starch as a core binder capable of being effectively blown by use of selective additives.
  • Such additives that have been found to effectively increase flowability are: sodium tripolyphosphate, sodium hexamethaphosphate, dicalcium phosphate dihydrate, sodium chloride, dimethylpolysiloxane and ethylic alcohol All these additives match very well with the water repellency additives described bellow.
  • Such additives that have been found to effectively control water repellency are: Alkyl silicone (Silres BS69050), triethoxi (2,4,4 trimetilpentil) silane, octyl triethoxi silane plus alkyl silicone Silres BS 16, Wax emulsions, paraffin waxes, wax polymers, natural and paraffin wax combinations under different trade names were tested with acceptable results.
  • Such water repellency additives that have been found to be particularly useful in this invention are: triethoxi (2,4,4 trimetilpentil) silane, octyl triethoxi silane plus alkyl silicone and Alkyl silicone (Silres BS69050).
  • amylose/amylopectin ratio for tapioca is given as 0.22.
  • amylose is a linear chain of 500 to 2000 glucose units
  • amylopectin is more massive and branched with linear chain lengths of 25-30 glucose units
  • Preferred embodiments of a binder according to the present invention comprise about 70%-95% starch (or more preferably 70-90%, or still more preferably 70-85%) plus additive(s) ⁇ such as, for example, preferably sodium tripolyphosphate and silicon or Silres BS 16, or their functional equivalents).
  • Silres BS®16 is the tradename of Wacker Chemie, AG for a concentrated water solution of 1-5% potassium hydroxide and 40-70% potassium methyl siliconate (per the list of ingredients in that company's Material Safety Data Sheet for the U.S.); more specifically, that company's product brochure for Silres BS®16 gives the solids content as 54 wt. % and the approximate active ingredients as 34%.
  • a preferred method for making a binder coated sand according to the present invention is by forming silica sand cores and molds for foundries utilizing a starchwater-based binder comprising mixing silica sand grains with starch in a suitable mixer, adding water to said sand and starch mixture and continue mixing said sand, starch, and water so that the sand grains are coated with starch (typically in about one minute); drying the starch-coated sand grains and treating them in a mill to break down lumps which might have been formed during the starch-coating step and screening the sand to separate said lumps; adding water to said coated sand grains and screening said sand grains for homogenizing and loosening said grains; adding sodium tripolyphosphate and silicon or Silres® BS 16; optionally adding dispersing additives; and blowing said cores and molds utilizing said starch-coated sand grains.
  • binder coated sand can also be made by direct mixing of sand and binder from starch and additives before blowing
  • the objects of the invention are also met by providing a core or mold made from the starch/water based binder composition of the present invention.
  • FIG. 1 shows a process block diagram illustrating the main steps of a method illustrating one preferred embodiment of the invention for the manufacture of sand molds and cores utilizing an artificially-modified tapioca type starch.
  • FIG. 2 shows a second preferred embodiment; being a process, similar to that in FIG. 1 , modified to utilize native tapioca type starch.
  • Silica sand cores are made from sand grains bound by a suitable binder which provides a strong bond between such sand grains in such a manner and with a sufficiency to withstand the handling of the cores and the assembled molds without losing the precise dimensions and form needed for impressing the desired geometry and surface quality to the casting under the temperature and pressure of the molten metal used to form said casting.
  • sand cores are shaped by mixing sand and a binder, blowing the binder-sand mixture into a mold having the desired shape, and curing or hardening the binder in the mold so that the mold geometry is fixed in the cores after their removal from said mold.
  • binders There are a variety of synthetic resins used as binders as is well known in the art. According to the present invention, a water-based binder and a method for forming the sand cores provide a number of advantages over the current state-of-the-art binders regarding manufacturing costs and core qualities.
  • the binder of the invention is mainly composed of starch.
  • starch has been utilized as an additive to prior-art binders, mostly in proportions of less than 20% of the binder composition, to the best of applicants' knowledge it has not previously been effectively used as the main constituent of a sand core-making binder in mass production foundries.
  • two additives are added to the starch, in the proportions and in the form explained below, which in combination with the starch, provide the desired qualities to the formed cores.
  • These additives are sodium tripolyphosphate and silicon or Silres BS 16. More broadly, the separate functions of the two additives with certain starches may be found in only one single additive.
  • starch suitable to be utilized as the basis of the binder composition of the invention.
  • One difference among them is the amount of starch needed to achieve the same mechanical strength.
  • potato requires more than 2% weight (based on sand) and for maize close to 2% weight.
  • Tapioca starch the core needs significantly less starch content to achieve the same strength.
  • Tapioca starch is thus preferably used but other varieties of starch can also be utilized according to broader aspects of the invention.
  • silica sand 10 is mixed with the artificially-modified starch 12 in a proportion of from about 0.5% to 3.0% by weight on the basis of the sand weight, in a paddle mixer 14 for a period of time from about 30 seconds to about 120 seconds. This period of time must be sufficient for achieving a good dispersion of the starch over the surface of the sand particles.
  • water 16 is slowly added to the sand-starch mixture preferably in a proportion from about 5% to 10% by weight on the basis of the sand weight and the sand-starch-water mixture is mixed in said mixer 14 for at least 1 minute, producing starch-coated sand grains 18 which are then allowed to dry naturally (indicated by dotted line 19 ) or optionally in a suitable drying furnace 20 for accelerating the drying process and thereby increasing the process productivity.
  • the furnace 20 can be of the type having forced air 17 .
  • the dry starch-coated sand 18 is then treated in a suitable mill 22 (for example, a ball mill or a vibrating shaker) for destroying the sand lumps which may have been formed during the previous step.
  • the milled coated sand 23 is screened on a screen 24 , for example utilizing a sieve # 30 for assuring that all the sand grains have a homogeneous particle size.
  • Sand lumps 25 separated from the coated loose sand grains, are recycled to mill 22 .
  • the starch-coated sand 23 undergoes a second mixing step in a mixer 28 where water 35 is added in a proportion preferably of at least 2% by weight on the basis of the sand weight, also sodium thipolyphosphate 32 is added in a proportion of from 0.1% to about 0.2% by weight on the basis of the sand weight, and silicon 34 from about 0.1% to 0.2% or Silres BS 16 from about 0.02% to 0.08%, resulting in sand ready for core blowing in blower 36 where the final core 38 is formed.
  • silica sand 10 is pre-heated to a temperature in the range from about 110° C. to about 130° C. in a furnace 13 .
  • the preheated sand is then transferred to the mixer 14 to follow the rest of the method in the same manner as above-described for the artificially modified starch.
  • Water 16 is also preferably heated to a temperature of about 70° C. in order to preserve as much as possible the temperature of the sand above about 70° C.
  • the amount of water 16 added at this mixing step should be sufficient to reach a humidity level in the range from about 2% to about 4% of the humid sand weight.
  • FIG. 2 The rest of the method illustrated in FIG. 2 is the same as in FIG. 1 .

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • General Health & Medical Sciences (AREA)
  • Molecular Biology (AREA)
  • Mold Materials And Core Materials (AREA)
US11/517,995 2006-09-08 2006-09-08 Binder composition and method of forming foundry sand cores and molds Abandoned US20080060778A1 (en)

Priority Applications (7)

Application Number Priority Date Filing Date Title
US11/517,995 US20080060778A1 (en) 2006-09-08 2006-09-08 Binder composition and method of forming foundry sand cores and molds
EP07859284A EP2107955A4 (en) 2006-09-08 2007-09-10 BINDER COMPOSITION AND PROCESS FOR PRODUCING SAND CORES AND FOUNDRY MOLDS
PCT/IB2007/004242 WO2008029302A2 (en) 2006-09-08 2007-09-10 Binder composition and method of forming foundry sand cores and molds
CA002662844A CA2662844A1 (en) 2006-09-08 2007-09-10 Binder composition and method of forming foundry sand cores and molds
US12/440,553 US20110042028A1 (en) 2006-09-08 2007-09-10 Binder composition amd method of forming foundry sand cores and molds
MX2009002490A MX2009002490A (es) 2006-09-08 2007-09-10 Composicion aglomerante y metodo para formar corazones y molde de arena para funciones.
ARP070103996A AR062728A1 (es) 2006-09-08 2007-09-11 Composicion aglomerante y metodo para formar corazones y moldes de arena para fundiciones

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US11/517,995 US20080060778A1 (en) 2006-09-08 2006-09-08 Binder composition and method of forming foundry sand cores and molds

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US12/440,553 Abandoned US20110042028A1 (en) 2006-09-08 2007-09-10 Binder composition amd method of forming foundry sand cores and molds

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EP (1) EP2107955A4 (es)
AR (1) AR062728A1 (es)
CA (1) CA2662844A1 (es)
MX (1) MX2009002490A (es)
WO (1) WO2008029302A2 (es)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20100267153A1 (en) * 2007-10-04 2010-10-21 William Andregg Sequencing Nucleic Acid Polymers with Electron Microscopy
US20140190651A1 (en) * 2011-06-21 2014-07-10 Jaguar Land Rover Limited Apparatus and Method for Embedding an Element
JP2016002573A (ja) * 2014-06-18 2016-01-12 旭有機材工業株式会社 鋳型の製法
JP2016002574A (ja) * 2014-06-18 2016-01-12 旭有機材工業株式会社 鋳型の製造法
US20210370388A1 (en) * 2020-06-01 2021-12-02 LightSpeed Concepts Inc. Tool-less method for making molds, cores, and temporary tools

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
MX2012006927A (es) 2009-12-18 2012-08-15 Tenedora Nemak Sa De Cv Composicion de aglomerante y metodo para formar corazones y moldes de arena para fundicion.
JP5249447B1 (ja) * 2012-05-17 2013-07-31 株式会社木村鋳造所 三次元積層造型用の鋳物砂
DE102014109598A1 (de) * 2014-07-09 2016-01-14 Tenedora Nemak, S.A. De C.V. Gießkern, Verwendung eines Gießkerns und Verfahren zur Herstellung eines Gießkerns
CN108723285B (zh) * 2018-07-11 2019-12-03 佛山市杨森化工有限公司 一种高湿压强度型砂粘结剂材料的制备方法
CN109465380B (zh) * 2019-01-04 2021-08-10 山东永创材料科技有限公司 一种高强度铸铁用粘结剂

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2508359A (en) * 1947-02-21 1950-05-23 Rose C Baker Core binder
US3642503A (en) * 1970-06-08 1972-02-15 Foseco Int Process for bonding particulate materials
US4070196A (en) * 1975-09-15 1978-01-24 Foseco International Limited Binder compositions
US4158574A (en) * 1975-02-21 1979-06-19 Krause Milling Company Hydrolyzed amylaceous product and process of making the same
US5582231A (en) * 1995-04-28 1996-12-10 General Motors Corporation Sand mold member and method

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3462503A (en) * 1965-06-14 1969-08-19 Atlantic Richfield Co Telomerization of ethylene
US4196768A (en) * 1977-08-04 1980-04-08 Yamato Manufacturing Co., Ltd. Casting mold manufacturing process and apparatus therefor
US4763720A (en) * 1986-06-23 1988-08-16 Kabushiki Kaisha Komatsu Seisakusho Microwave process for the fabrication of cores for use in foundry casting
US5215143A (en) * 1992-11-16 1993-06-01 American Colloid Company Non-porous carbon molding (foundry) sand and method of casting
US6139619A (en) * 1996-02-29 2000-10-31 Borden Chemical, Inc. Binders for cores and molds
US6040355A (en) * 1998-07-01 2000-03-21 Kurple; Kenneth R Foundry curing system
US6833097B2 (en) * 2000-01-03 2004-12-21 Japan Corn Starch Co. Ltd. Biodegradable block for models
EP1661639B1 (en) * 2003-09-02 2018-10-10 Sintokogio, Ltd. Method of forming mold and core for metal casting

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2508359A (en) * 1947-02-21 1950-05-23 Rose C Baker Core binder
US3642503A (en) * 1970-06-08 1972-02-15 Foseco Int Process for bonding particulate materials
US4158574A (en) * 1975-02-21 1979-06-19 Krause Milling Company Hydrolyzed amylaceous product and process of making the same
US4070196A (en) * 1975-09-15 1978-01-24 Foseco International Limited Binder compositions
US5582231A (en) * 1995-04-28 1996-12-10 General Motors Corporation Sand mold member and method

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20100267153A1 (en) * 2007-10-04 2010-10-21 William Andregg Sequencing Nucleic Acid Polymers with Electron Microscopy
US20140190651A1 (en) * 2011-06-21 2014-07-10 Jaguar Land Rover Limited Apparatus and Method for Embedding an Element
US9724752B2 (en) * 2011-06-21 2017-08-08 Jaguar Land Rover Limited Apparatus and method for embedding an element
JP2016002573A (ja) * 2014-06-18 2016-01-12 旭有機材工業株式会社 鋳型の製法
JP2016002574A (ja) * 2014-06-18 2016-01-12 旭有機材工業株式会社 鋳型の製造法
US20210370388A1 (en) * 2020-06-01 2021-12-02 LightSpeed Concepts Inc. Tool-less method for making molds, cores, and temporary tools

Also Published As

Publication number Publication date
MX2009002490A (es) 2009-05-11
AR062728A1 (es) 2008-11-26
EP2107955A4 (en) 2010-08-04
US20110042028A1 (en) 2011-02-24
WO2008029302A3 (en) 2009-08-27
CA2662844A1 (en) 2008-03-13
EP2107955A2 (en) 2009-10-14
WO2008029302A2 (en) 2008-03-13

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Owner name: TENEDORA NEMAK, S.A. DE C.V., MEXICO

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:VELASCO-TELLEZ, ABRAHAM;VALTIERRA-GALLARDO, SALVADOR;GARCIA, GILBERTO;AND OTHERS;REEL/FRAME:019535/0231

Effective date: 20061003

STCB Information on status: application discontinuation

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Owner name: TENEDORA NEMAK, S.A. DE C.V., MEXICO

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:VELASCO-TELLEZ, ABRAHAM;VALTIERRA-GALLARDO, SALVADOR;GARCIA-TAPIA, GILBERTO;AND OTHERS;REEL/FRAME:023681/0614

Effective date: 20091215