US2102122A - Foundry core and dry binder for the preparation thereof - Google Patents
Foundry core and dry binder for the preparation thereof Download PDFInfo
- Publication number
- US2102122A US2102122A US95706A US9570636A US2102122A US 2102122 A US2102122 A US 2102122A US 95706 A US95706 A US 95706A US 9570636 A US9570636 A US 9570636A US 2102122 A US2102122 A US 2102122A
- Authority
- US
- United States
- Prior art keywords
- core
- resin
- gasoline
- binder
- hydrocarbon
- 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.)
- Expired - Lifetime
Links
- 238000002360 preparation method Methods 0.000 title description 3
- 239000002706 dry binder Substances 0.000 title description 2
- 239000011347 resin Substances 0.000 description 23
- 229920005989 resin Polymers 0.000 description 23
- 239000002023 wood Substances 0.000 description 20
- 239000011230 binding agent Substances 0.000 description 18
- 239000000203 mixture Substances 0.000 description 18
- 239000004215 Carbon black (E152) Substances 0.000 description 12
- 235000019764 Soybean Meal Nutrition 0.000 description 12
- 229930195733 hydrocarbon Natural products 0.000 description 12
- 150000002430 hydrocarbons Chemical class 0.000 description 12
- 239000004455 soybean meal Substances 0.000 description 12
- 235000008331 Pinus X rigitaeda Nutrition 0.000 description 11
- 235000011613 Pinus brutia Nutrition 0.000 description 11
- 241000018646 Pinus brutia Species 0.000 description 11
- 239000004576 sand Substances 0.000 description 7
- RSWGJHLUYNHPMX-UHFFFAOYSA-N Abietic-Saeure Natural products C12CCC(C(C)C)=CC2=CCC2C1(C)CCCC2(C)C(O)=O RSWGJHLUYNHPMX-UHFFFAOYSA-N 0.000 description 6
- KHPCPRHQVVSZAH-HUOMCSJISA-N Rosin Natural products O(C/C=C/c1ccccc1)[C@H]1[C@H](O)[C@@H](O)[C@@H](O)[C@@H](CO)O1 KHPCPRHQVVSZAH-HUOMCSJISA-N 0.000 description 6
- 230000008020 evaporation Effects 0.000 description 6
- 238000001704 evaporation Methods 0.000 description 6
- KHPCPRHQVVSZAH-UHFFFAOYSA-N trans-cinnamyl beta-D-glucopyranoside Natural products OC1C(O)C(O)C(CO)OC1OCC=CC1=CC=CC=C1 KHPCPRHQVVSZAH-UHFFFAOYSA-N 0.000 description 6
- 239000011280 coal tar Substances 0.000 description 5
- 239000003209 petroleum derivative Substances 0.000 description 5
- 235000015112 vegetable and seed oil Nutrition 0.000 description 5
- 239000008158 vegetable oil Substances 0.000 description 5
- 238000005266 casting Methods 0.000 description 4
- 239000000944 linseed oil Substances 0.000 description 4
- 239000003921 oil Substances 0.000 description 4
- 235000019198 oils Nutrition 0.000 description 4
- 238000003860 storage Methods 0.000 description 4
- 244000068988 Glycine max Species 0.000 description 3
- 235000010469 Glycine max Nutrition 0.000 description 3
- 235000013339 cereals Nutrition 0.000 description 3
- 235000021388 linseed oil Nutrition 0.000 description 3
- 235000012424 soybean oil Nutrition 0.000 description 3
- 239000003549 soybean oil Substances 0.000 description 3
- 239000005018 casein Substances 0.000 description 2
- BECPQYXYKAMYBN-UHFFFAOYSA-N casein, tech. Chemical compound NCCCCC(C(O)=O)N=C(O)C(CC(O)=O)N=C(O)C(CCC(O)=N)N=C(O)C(CC(C)C)N=C(O)C(CCC(O)=O)N=C(O)C(CC(O)=O)N=C(O)C(CCC(O)=O)N=C(O)C(C(C)O)N=C(O)C(CCC(O)=N)N=C(O)C(CCC(O)=N)N=C(O)C(CCC(O)=N)N=C(O)C(CCC(O)=O)N=C(O)C(CCC(O)=O)N=C(O)C(COP(O)(O)=O)N=C(O)C(CCC(O)=N)N=C(O)C(N)CC1=CC=CC=C1 BECPQYXYKAMYBN-UHFFFAOYSA-N 0.000 description 2
- 235000021240 caseins Nutrition 0.000 description 2
- 235000013312 flour Nutrition 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 235000012054 meals Nutrition 0.000 description 2
- 229920006395 saturated elastomer Polymers 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 101100123850 Caenorhabditis elegans her-1 gene Proteins 0.000 description 1
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 206010010071 Coma Diseases 0.000 description 1
- 240000006240 Linum usitatissimum Species 0.000 description 1
- 235000004431 Linum usitatissimum Nutrition 0.000 description 1
- 235000010627 Phaseolus vulgaris Nutrition 0.000 description 1
- 244000046052 Phaseolus vulgaris Species 0.000 description 1
- LSNNMFCWUKXFEE-UHFFFAOYSA-N Sulfurous acid Chemical compound OS(O)=O LSNNMFCWUKXFEE-UHFFFAOYSA-N 0.000 description 1
- 235000013405 beer Nutrition 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000009833 condensation Methods 0.000 description 1
- 230000005494 condensation Effects 0.000 description 1
- 239000000470 constituent Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 235000004426 flaxseed Nutrition 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- ZZUFCTLCJUWOSV-UHFFFAOYSA-N furosemide Chemical compound C1=C(Cl)C(S(=O)(=O)N)=CC(C(O)=O)=C1NCC1=CC=CO1 ZZUFCTLCJUWOSV-UHFFFAOYSA-N 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 238000000227 grinding Methods 0.000 description 1
- 239000004615 ingredient Substances 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 235000013379 molasses Nutrition 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 239000003208 petroleum Substances 0.000 description 1
- 150000008442 polyphenolic compounds Chemical class 0.000 description 1
- 235000013824 polyphenols Nutrition 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 239000002244 precipitate Substances 0.000 description 1
- 239000003755 preservative agent Substances 0.000 description 1
- 230000002335 preservative effect Effects 0.000 description 1
- 235000020183 skimmed milk Nutrition 0.000 description 1
- 239000000779 smoke Substances 0.000 description 1
- 239000011269 tar Substances 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
Classifications
-
- 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
- B22C1/22—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 resins or rosins
- B22C1/2293—Natural polymers
-
- 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
- B22C1/24—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 oily or fatty substances; of distillation residues therefrom
Definitions
- ,dry or liquid binders epg. pulverized foundry pitch, pulverized rosin, pulverized cereal, pulverized casein, sulfite, pulp waste liquor, molasses,
- sour beer linseed,1soya bean,,or other vegetable oil, oil-rosin mixtures,- known ascore oils, etc.
- Each of the above mentioned core binders has Foundry pitch has no "green strength" and is also hard to clean from the cavity. Pulverized rosin reverts to solid rosin on storage, 1. e. flows together to form a solid mass.
- Rosin-kerosene-linseed oil mixtures tend to crystallize and precipitate the rosin on storage.
- Cereal binders produce cores which swell, absorb moisture, and give rise to large volumes of acrid smoke in the casting operation.
- Liquid core binders migrate to the surface of the core and form a hard, impenetrable skin. Linseed oil binder must dry by oxidation, which slows down production. Casein, skimmed milk, etc., are hydro'scopic and putrescible when used in cores.
- binder and cores ;madetherefrom is hereby de- 5 1 fined as the resin such as may be produced from resinous wood, described and claimed in application,Serial No. 61,745, filed January 31 l936,-by Lucius C. Hall, which resin maybe produced by extracting resinous wood with acoal tar hydrocarbon, removing said hydrocarbon by evaporation, leavinga residue comprising a mixture of wood rosin and the new resin, extracting wood rosin from saidresidue by a petroleum hydroe carbon, leaving thenew, gasoline-insoluble, pine wood resin, p
- the unextracted soybean 1 meal used in my improved core binder contains appreciable, but variable, quantities of soya bean oil which latter enters into the composition.
- soybean meal or flour which contains usually about 17% of oil, when mixed with the gasoline-insoluble pine wood resin above described, causes a reaction during the baking, in which the oil and the resin form a condensate, resulting in the production in a short baking period of a high-strength, superior core.
- my improved foundry core composition I mix intimately, for example by grinding together, unextracted soya bean meal and the gasoline-insoluble pine wood resin, hereinbefore described. For example, equal parts thereof may be ground together, and cores made therewith by mixing such composition with foundry sand in a ratio of, for example, 55 parts by weight of sand to 1 part by weight of the composition, and baking the core for about 1.5 hours at about 425 F.
- the green strength of such cores is satisfactory before baking, and after baking the core has a tensile strength of 177 pounds per square inch.
- baked cores may, as a test, be stored in a moisture-saturated atmosphere overnight, and found, after such storage, to have a tensile strength of about 165 poundsper square inch, i. e., a loss of less than 7%. Storage in a moisture-saturated atmosphere causes a severe loss in strength of cores produced by methods heretofore employed.
- my improved core compositions are practically non-putrescent, due to the presence therein of my special resin, hereinbeiore described, which resin contains certain, complex polyphenols, which act as a preservative
- a further advantage of my improved core compositions is that they are dry, and easy to use, as compared to the fluid or semifiuid compositions heretofore used.
- I may add additional soybean oil to my core binder composition, or I may use extracted soybean meal and soybean oil, in place of unextracted soybean meal, thus reproducing, in effect, unextracted soybean meal.
- I may also employ extracted soybean meal and other vegetable oils, such as linseed oil, in place of unextracted soybean meal, and still obtain the advantages, due to the presence oi. the gasoline-insoluble pine wood resin, of superior strength of core and hardening by condensation eifects.
- a core binder a mixture of soybean meal containing a vegetable oil, and a gasoline-insoluble, pine wood resin produced by extracting resinous wood with "a coal tar hydrocarbon, removing said hydrocarbon by evaporation, extracting the residue with a petroleum hydrocarbon, and recovering a gasoline-insoluble resin.
- a core binder a mixture of soybean meal, a vegetable oil, and a gasoline-insoluble, pine wood resin produced by extracting resinous wood with a coal tar hydrocarbon, removing said hydrocarbon by evaporation, extracting the residue with a petroleum hydrocarbon, and recovering a gasoline-insoluble resin.
- a core binder a mixture of unextracted soybean meal and a gasoline-insoluble, pine wood resin produced by extracting resinous wood with a coal tar hydrocarbon, removing said hydrocarbon by evaporation, extracting the residue with a petroleum hydrocarbon, and recovering a gasoline-insoluble resin.
- a core binder a mixture of equal parts of unextracted soybean meal and a gasolineinsoluble, pine wood resin intimately mixed together, said pine wood resin being produced by extracting resinous wood with a coal tar hydrocarbon, removing said hydrocarbon by evaporation, extracting the residue with a petroleum hydrocarbon, and recovering a gasoline-insoluble resin.
- a green foundry core consisting of core sand, unextracted soybean meal and a gasolineinsoluble, pine wood resin produced by extracting resinous wood with a coal tar hydrocarbon, removing said hydrocarbon by evaporation, extracting the residue with a petroleum hydrocarbon, and recovering a gasoline-insoluble resin.
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Mold Materials And Core Materials (AREA)
Description
Patented Dec. 14, 1937 PATENT OFFICE Fomsmw coma AND nay Bmnnaron THE- 1 1 PREPARATION THEREOF [Fred H. LaheJHillsdale, N. Y., assignor to Her- 1 les Powder Company, Wilmington, Del., 11
corporation" of Delaware N6, rawin Application August 12, .1936, 1 1 Serial No. 95,706 .1 v
1 "l his linvention[relates to foundry cores and dry binders for thepreparation thereof.
1Heretoiore, in makingfoundry, cores for use. in
the productionof castings, it has been the practice1to mix coresand withone-of a -.variety,of
,dry or liquid binders, epg. pulverized foundry pitch, pulverized rosin, pulverized cereal, pulverized casein, sulfite, pulp waste liquor, molasses,
sour beer, linseed,1soya bean,,or other vegetable oil, oil-rosin mixtures,- known ascore oils, etc.
"Themixture of sand and binder is then moistened.
with suiiicient water, so that item be rammed or blown into core boxes of various shapes and sizes, corresponding to the shapes and sizes of cavities it is desired to produce by means of the coresn 1 1 When the core box is removed; the grains of sand must be bound together by the binder, so
its disadvantages.
as topermit handling in an approved manner and transferring to .an oven. inthe oven the cores are then baked to expel the water, drive off volatile constituents, and make the corecapable of withstanding ferrostatic pressure encountered in the casting operation. 1
Incasting, the heat of the molten metal burns l 1 out the binder, 1 the gases from which vent through the cores and molds, leaving the core in a friable form or as loosely held sand, readily removable from the cavity in the casting when cooled. 1
Each of the above mentioned core binders has Foundry pitch has no "green strength" and is also hard to clean from the cavity. Pulverized rosin reverts to solid rosin on storage, 1. e. flows together to form a solid mass.
Rosin-kerosene-linseed oil mixtures (coreoils) tend to crystallize and precipitate the rosin on storage. Cereal binders produce cores which swell, absorb moisture, and give rise to large volumes of acrid smoke in the casting operation. Liquid core binders migrate to the surface of the core and form a hard, impenetrable skin. Linseed oil binder must dry by oxidation, which slows down production. Casein, skimmed milk, etc., are hydro'scopic and putrescible when used in cores.
resin overcomes the above difliculties encountered in the uselof oldart core binders. l
The gasoline-insoluble, pinewood resinI em- 1 ploy in the preparation 'of my improved core,
binder and cores ;madetherefrom is hereby de- 5 1 fined as the resin such as may be produced from resinous wood, described and claimed in application,Serial No. 61,745, filed January 31 l936,-by Lucius C. Hall, which resin maybe produced by extracting resinous wood with acoal tar hydrocarbon, removing said hydrocarbon by evaporation, leavinga residue comprising a mixture of wood rosin and the new resin, extracting wood rosin from saidresidue by a petroleum hydroe carbon, leaving thenew, gasoline-insoluble, pine wood resin, p
' It will be noted thatthe unextracted soybean 1 meal used in my improved core binder, contains appreciable, but variable, quantities of soya bean oil which latter enters into the composition.
I have found that pulverized, gasoline-insoluble pine wood resin, as described above, possesses poor green strength when used as a core binder. However, this poor green strength is overcome by the admixture with thetoughening unextracted soybean meal or flour. I have also found that while cores made with linseed oil, soybean oil, or other vegetable oils, require longbaking at high temperatures, soybean meal or flour, which contains usually about 17% of oil, when mixed with the gasoline-insoluble pine wood resin above described, causes a reaction during the baking, in which the oil and the resin form a condensate, resulting in the production in a short baking period of a high-strength, superior core. 1
In preparing my improved foundry core composition I mix intimately, for example by grinding together, unextracted soya bean meal and the gasoline-insoluble pine wood resin, hereinbefore described. For example, equal parts thereof may be ground together, and cores made therewith by mixing such composition with foundry sand in a ratio of, for example, 55 parts by weight of sand to 1 part by weight of the composition, and baking the core for about 1.5 hours at about 425 F. The green strength of such cores is satisfactory before baking, and after baking the core has a tensile strength of 177 pounds per square inch. Furthermore, such baked cores may, as a test, be stored in a moisture-saturated atmosphere overnight, and found, after such storage, to have a tensile strength of about 165 poundsper square inch, i. e., a loss of less than 7%. Storage in a moisture-saturated atmosphere causes a severe loss in strength of cores produced by methods heretofore employed.
Furthermore, I have found that my improved core compositions are practically non-putrescent, due to the presence therein of my special resin, hereinbeiore described, which resin contains certain, complex polyphenols, which act as a preservative A further advantage of my improved core compositions is that they are dry, and easy to use, as compared to the fluid or semifiuid compositions heretofore used.
It will be appreciated that other proportions of ingredients may be used by me in preparing my improved core composition, depending upon the size, type, or complexity of the core it is desired to produce. Nor do I limit myself to the sand/binder ratio or temperature or time or baking, given above by way of example.
It will also be appreciated that I may add additional soybean oil to my core binder composition, or I may use extracted soybean meal and soybean oil, in place of unextracted soybean meal, thus reproducing, in effect, unextracted soybean meal. I may also employ extracted soybean meal and other vegetable oils, such as linseed oil, in place of unextracted soybean meal, and still obtain the advantages, due to the presence oi. the gasoline-insoluble pine wood resin, of superior strength of core and hardening by condensation eifects.
What I claim and desire to protect by Letters Patent is:
1. As a core binder, a mixture of soybean meal containing a vegetable oil, and a gasoline-insoluble, pine wood resin produced by extracting resinous wood with "a coal tar hydrocarbon, removing said hydrocarbon by evaporation, extracting the residue with a petroleum hydrocarbon, and recovering a gasoline-insoluble resin.
2. As a core binder, a mixture of soybean meal, a vegetable oil, and a gasoline-insoluble, pine wood resin produced by extracting resinous wood with a coal tar hydrocarbon, removing said hydrocarbon by evaporation, extracting the residue with a petroleum hydrocarbon, and recovering a gasoline-insoluble resin.
3. As a core binder, a mixture of unextracted soybean meal and a gasoline-insoluble, pine wood resin produced by extracting resinous wood with a coal tar hydrocarbon, removing said hydrocarbon by evaporation, extracting the residue with a petroleum hydrocarbon, and recovering a gasoline-insoluble resin.
4. As a core binder, a mixture of equal parts of unextracted soybean meal and a gasolineinsoluble, pine wood resin intimately mixed together, said pine wood resin being produced by extracting resinous wood with a coal tar hydrocarbon, removing said hydrocarbon by evaporation, extracting the residue with a petroleum hydrocarbon, and recovering a gasoline-insoluble resin.
5. A green foundry core consisting of core sand, unextracted soybean meal and a gasolineinsoluble, pine wood resin produced by extracting resinous wood with a coal tar hydrocarbon, removing said hydrocarbon by evaporation, extracting the residue with a petroleum hydrocarbon, and recovering a gasoline-insoluble resin.
FRED H. LANE.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US95706A US2102122A (en) | 1936-08-12 | 1936-08-12 | Foundry core and dry binder for the preparation thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US95706A US2102122A (en) | 1936-08-12 | 1936-08-12 | Foundry core and dry binder for the preparation thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US2102122A true US2102122A (en) | 1937-12-14 |
Family
ID=22253239
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US95706A Expired - Lifetime US2102122A (en) | 1936-08-12 | 1936-08-12 | Foundry core and dry binder for the preparation thereof |
Country Status (1)
| Country | Link |
|---|---|
| US (1) | US2102122A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2494744A (en) * | 1948-02-06 | 1950-01-17 | Chicago Mill & Lumber Co | Glue |
| DE1102979B (en) * | 1955-09-23 | 1961-03-23 | Hercules Powder Co Ltd | Binder for foundry molds and cores |
-
1936
- 1936-08-12 US US95706A patent/US2102122A/en not_active Expired - Lifetime
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2494744A (en) * | 1948-02-06 | 1950-01-17 | Chicago Mill & Lumber Co | Glue |
| DE1102979B (en) * | 1955-09-23 | 1961-03-23 | Hercules Powder Co Ltd | Binder for foundry molds and cores |
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