CN104338892A - Stabilizing agent added to green sand mold - Google Patents
Stabilizing agent added to green sand mold Download PDFInfo
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- CN104338892A CN104338892A CN201310328604.4A CN201310328604A CN104338892A CN 104338892 A CN104338892 A CN 104338892A CN 201310328604 A CN201310328604 A CN 201310328604A CN 104338892 A CN104338892 A CN 104338892A
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- stabilization agent
- sand mold
- green sand
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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
- B22C1/02—Compositions of refractory mould or core materials; Grain structures thereof; Chemical or physical features in the formation or manufacture of moulds characterised by additives for special purposes, e.g. indicators, breakdown additives
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Abstract
The invention provides a stabilizing agent added to a green sand mold. The stabilizing agent comprises a binding agent and an additive, wherein the binding agent is a phenol derivative; a plurality of functional groups are used for replacing hydrogen atoms, and are bonded; the binding agent is 75-85% of the total weight; and the additive contains a plurality of microelements, wherein the weight ratio of the binding agent to the additive is 4: 1, thereby, the physical characteristics of the green sand mold are improved so as to be as a reference of sand mixing, molding and casting flaw analysis.
Description
Technical field
The present invention is relevant with a kind of stabilization agent, espespecially a kind of stabilization agent that can be used for interpolation green sand mold.
Background technology
Green sand mold casting (Green Sand Molding Process) is from ancient times along one of modeling method reaching modern most long history, along with the progress in epoch, this kind of molding method is not only eliminated, on the contrary along with the progress of science and technology, it also expands the scope of application in each field of industry, more in molding materials, method or equipment aspect all have with time the performance that progresses greatly and achievement, in addition, one of method that green sand mold casting also the most generally uses for domestic and international foundry industry, and green sand mold casting so extensively adopted by the same trade, its main cause is just that to utilize this kind of method to have moulding easy, productivity is high, the advantages such as the comparatively cheap and recyclable recycling of sand of cost.
The basic composition of green sand mold mainly comprises silica sand, clay, water, but, the good and bad degree of modeling grittiness matter, usually the quality of the quality of the rear gained foundry goods of casting can also be had influence on, wherein, the modeling sand mixed is made to have certain special nature if expect, such as improve sand mo(u)ld intensity, be easy to withdrawing pattern etc., then can add the additive such as dextrin, pitch, to change the physical characteristic of modeling sand, therefore, with the progress of science and technology today, for obtaining the good and foundry goods of fineness of quality, the character of strict keyholed back plate green sand mold is instant work in fact.
But, physical property for modeling sand is inquired into, can by after adding additive, the various physical propertys of modeling sand are converted into data via experiment method, respectively in addition record, wherein, can for different additive to improve hygrometric state compressive strength, air permeability, compression ratio, surperficial stability and moisture etc. experiment parameter, to improve the quality of modeling sand, its each experiment parameter for green sand mold impact as described below:
Hygrometric state compressive strength, the large I of its numerical value affects the defect level of anti-expansion, makes it determine the integrality of sand mo(u)ld in course of conveying, and the sand removal of foundry goods, can understand which kind of metal material applicable.
Air permeability, can the large I of its numerical value determines that sand contacts produced gas with high-temperature liquid metal, overflow, and then affect the gas hole defect of foundry goods by between sand particle.
Compression ratio, its numerical value is on the low side, then represent sand water content low, easily causes moldability poor; not easily withdrawing pattern, if compression ratio is higher, represents then sand stream motionless not good; sand mo(u)ld is tamping not easily, causes sand mo(u)ld intensity not enough, easily produces the foundry defect such as pore, pin hole when easily producing swollen mould or casting.
Surface stability, the large I of its numerical value determines the quality of foundry goods, and affects the surface roughness of foundry goods.
Moisture, the adjustment of moisture content must be relied on to control compression ratio for obtaining correct compression ratio, but the change formed in sand often changes the relation between compression ratio and moisture, if moisture is too high in sand, the problems such as pin hole can be produced, therefore, the scope of moisture must be stipulated, the composition so just in discernable sand.
Being directed to green sand mold casting, above-described experiment parameter, is all the reference as joining sand, modeling, foundry goods defect analyses.
Summary of the invention
Because above-mentioned shortcoming, the invention provides a kind of stabilization agent for adding green sand mold, using and improving hygrometric state compressive strength, air permeability, compression ratio, surperficial stability and moisture, to promote the quality of modeling sand.
The invention provides a kind of stabilization agent for adding green sand mold, it comprises: a binding agent, and it is the derivative of a phenol, and replaces hydrogen atom bond in addition with multiple functional group, and binding agent accounts for 75% ~ 85% of gross weight; And an additive, it contains various trace elements; Wherein, the weight ratio of binding agent and additive is 4:1.
Wherein, those trace elements are for including sulphur (S), magnesium (Mg), sodium (Na), calcium (Ca).
Wherein, those functional groups include ketone group (Ketone group), aldehyde radical (Aldehyde group), ester cyclic group (Alicyclic group), elementary ethanol based (Primary alcohol group), secondary ethanol based (Secondary alcohol group) and thiazolinyl (Alkene group).
Wherein, the structure of this binding agent as shown in Figure 1.
Wherein, the percentage by weight of this binding agent is 81%.
Wherein, the percentage by weight of this additive is in 19%.
Wherein, this binding agent is added the solute of formation one brown powdery with additive.
Wherein, the bulk density of this solute is between 25 ~ 30g/cm
3.
Wherein, the pH value of this solute is between 5 ~ 6.
Wherein, the cold water solubility of this solute is 92%.
Above, effect that the present invention reaches, lies in green sand mold after adding stabilization agent of the present invention, obviously can promote the hygrometric state compressive strength in green sand mold physical property and surperficial stability.
Accompanying drawing explanation
Fig. 1: be the chemical structural drawing of binding agent of the present invention.
Fig. 2: be experiment flow block diagram of the present invention.
Fig. 3: be the curve map of stabilization agent of the present invention and commercially available stabilization agent A and the corresponding hygrometric state compressive strength of B Different adding amount.
Fig. 4: be the curve map of stabilization agent of the present invention and commercially available stabilization agent A and the corresponding air permeability of B Different adding amount.
Fig. 5: be the curve map of stabilization agent of the present invention and commercially available stabilization agent A and the corresponding surperficial stability of B Different adding amount.
Fig. 6: be the curve map of stabilization agent of the present invention and commercially available stabilization agent A and the corresponding compression ratio of B Different adding amount.
Fig. 7: be the curve map of stabilization agent of the present invention and commercially available stabilization agent A and the corresponding moisture of B Different adding amount.
Fig. 8: be size distribution and the fineness number of Jin Jing's No. 5 silica sands.
Detailed description of the invention
For ease of the central idea that the present invention is represented in foregoing invention content one hurdle is described, hereby express with specific embodiment.In embodiment, various different object system is in being suitable for the ratio enumerating explanation, but not in the ratio of actual components and to draw, conjunction is first chatted bright.
Refer to shown in Fig. 1, Fig. 1 is the chemical structural drawing of binding agent of the present invention.Stabilization agent for adding green sand mold of the present invention, it comprises:
One binding agent, it is the derivative of a phenol, and replace hydrogen atom bond in addition with multiple functional group, and this binding agent accounts for 75% ~ 85% of gross weight, and those functional groups include ketone group (Ketone group), aldehyde radical (Aldehyde group), ester cyclic group (Alicyclic group), elementary ethanol based (Primary alcohol group), secondary ethanol based (Secondary alcohol group) and thiazolinyl (Alkene group), wherein, those functional groups all have the electron cloud of high polarity, and can for attracting the functional group that knot is different, and the effect of a bonding can be produced in solution.
One additive, it contains various trace elements, and wherein, those trace elements include sulphur (S), magnesium (Mg), sodium (Na), calcium (Ca).
Wherein, the percentage by weight of binding agent and additive is respectively 81% and 19%, and the weight ratio of binding agent and additive is about be similar to 4:1, in the present embodiment, binding agent is added the solute of formation one brown powdery with additive, its bulk density can between 25 ~ 30g/cm3, and pH value can between 5 ~ 6, and cold water solubility is 92%, the parameter of above physical property, for the stakeholder of the usual knowledge of chemical field tool, all learn by simple experiment, seldom set forth at this.
More than be structure of the present invention and physical property general introduction, and experiment flow of the present invention and effect principle that can reach be presented below:
Refer to shown in Fig. 8, Fig. 8 is the size distribution (PAN) of Jin Jing's No. 5 silica sands and fineness number (GFN).First chat bright in experiment of the present invention, the raw sand adopted is Jin Jing's No. 5 silica sands, its size distribution as shown in Figure 8, other insert thing is water, the swollen soil in west (SPV), coal dust, stabilization agent (A, B, C), wherein, stabilization agent A is the present invention, and stabilization agent B is commercially available known auspicious middle starch, the binding agent that stabilization agent C provides for commercially available known John Winter & Co Ltd.
Refer to shown in Fig. 2, Fig. 2 is experiment flow figure of the present invention, in the present invention, system is with A, B, C tri-kinds of stabilization agents, the Different adding amount of collocation percentage by weight 0.3%, 0.6%, 0.9%, 1.2% 4 is for the impact of the various character of green sand mold, first the fixing silica sand of Jin Jing No. 5 that uses is poured in a puddle mixer, add after 1% water imposes and mix in advance 1 minute again, and then add swollen soil (12%), coal dust (1%), stabilization agent, water (2%) carries out 4 minutes formally mixing, and takes out the modeling sand mixed afterwards.
Then, the modeling sand that said method has been mixed, make it after the screen cloth of 6Mesh, be filled in a forming tube, and utilize an extruder to make the standard test piece of green sand mold, and make the size of sand standard test piece within the scope of 50L (501) mm, every sand property test can be carried out, include hygrometric state compressive strength, air permeability, compression ratio, surperficial stability and moisture etc. project, wherein, the account form of each experiment parameter above-mentioned is all the ABC that association area can be known, does not add to repeat at this.
Refer to shown in Fig. 3, Fig. 3 is the curve map of various stabilization agent hygrometric state compressive strength corresponding to Different adding amount, from upper figure, stabilization agent A of the present invention along with the increase (0.3 ~ 1.2wt%) of addition, its hygrometric state compressive strength with rising; Stabilization agent B and stabilization agent C is then along with the increase (0.3 ~ 1.2wt%) of addition, and its hygrometric state compressive strength then declines gradually.
Generally speaking, add stabilization agent in green sand mold after, the no matter kind of stabilization agent and the number of addition, with do not add compare time, its hygrometric state compressive strength all has the phenomenon of lifting; But, if with the variety classes of stabilization agent, wherein, the most obvious with the effect of stabilization agent A of the present invention, that is the increase (0.3% ~ 1.2%wt%) of addition along with stabilization agent, its hygrometric state compressive strength also with rising (be increased to 0.58kgf/cm2 by 0.53, about increase by 9.4%).The effect of stabilization agent B and stabilization agent C, all along with the increase of the addition of stabilization agent, make its hygrometric state compressive strength also with decline, stabilization agent B (drops to 0.42kgf/cm2 by 0.49, about decline 14.3%), stabilization agent C (drops to 0.45kgf/cm2 by 0.5, about decline 10%), in addition, when the addition of stabilization agent B reaches 1.2wt%, its hygrometric state compressive strength (0.42kgf/cm2) is slightly poorer than the hygrometric state compressive strength (0.43kgf/cm2) of not adding stabilization agent.
Refer to shown in Fig. 4, Fig. 4 is stabilization agent of the present invention and the curve map of commercially available stabilization agent A and the corresponding hygrometric state compressive strength of B Different adding amount, and from upper figure, along with the increase of the addition of stabilization agent, the air permeability of its three kinds of stabilization agents declines all gradually.
Generally speaking, add stabilization agent in green sand mold after, the no matter kind of stabilization agent and the number (0.3 ~ 1.2wt%) of addition, with do not add compare time, its air permeability is all deteriorated; Wherein, the air permeability of stabilization agent A of the present invention drops to 138.6 (about declining 6%) by 147.4, the air permeability of stabilization agent B drops to 129.6 by 144.8 and (about declines (10.5%), the air permeability of stabilization agent C then drops to 134.3 (about declining 10.7%) by 150.4, learn according to above-mentioned experimental result, the addition one timing (0.3 ~ 1.2wt%) of A, B, C tri-kinds of stabilization agents, except during addition 0.3wt%, the size order of air permeability is all: stabilization agent A> stabilization agent C> stabilization agent B.
Refer to shown in Fig. 5, Fig. 5 is stabilization agent of the present invention and the curve map of commercially available stabilization agent A and the corresponding surperficial stability of B Different adding amount, from upper figure, stabilization agent A is along with the increase of addition, and its surperficial stability (SSI) all presents the trend slightly increasing or maintain an equal level; And stabilization agent B and stabilization agent C, then along with the increase (0.3 ~ 1.2wt%) of addition, its surperficial stability all presents the trend thereupon diminished.
Generally speaking, add stabilization agent in green sand mold after, the no matter kind of stabilization agent and the number (0.3 ~ 1.2wt%) of addition, its variation tendency is roughly identical with aforesaid hygrometric state compressive strength, only having stabilization agent A of the present invention when addition 1.2wt%, is belong to fair trend; But, if when comparing with the variety classes of stabilization agent, wherein the most obvious with the effect of stabilization agent A of the present invention, that is the increase (0.3 ~ 0.9wt%) of addition along with stabilization agent, its surperficial stability (SSI) rises thereupon and is increased to 66.8% by 64.7%, about increases by 2.1%.The effect of stabilization agent B and stabilization agent C, then along with the increase of addition, the decline gradually that its surperficial stability is then contrary, wherein, the surperficial stability of stabilization agent B drops to 46.6% by 59.9%, about declines 13.3%, the surperficial stability of stabilization agent C then drops to 40.4% by 51.5%, about declines 11.1%.In green sand mold, when to add stabilization agent B and its addition be 0.9 ~ 1.2wt% and when its addition of stabilization agent C is 0.6 ~ 1.2wt%, its surperficial stability is all also poor than (surperficial stability is 50%) when not adding stabilization agent.
Refer to shown in Fig. 6, Fig. 6 is stabilization agent of the present invention and the curve map of commercially available stabilization agent A and the corresponding compression ratio of B Different adding amount, and from upper figure, along with the increase of the addition of stabilization agent, the compactibility being added with three kinds of stabilization agents declines all gradually.
Generally speaking, add stabilization agent in green sand mold after, the no matter kind of stabilization agent and the number (0.3 ~ 1.2wt%) of addition, with do not add compare time, its compression ratio (CB value) all diminishes, but, if when comparing with the variety classes of stabilization agent, wherein the most obvious to add the effect that its compression ratio declines after stabilization agent B, that is along with the increase (0.3 ~ 1.2wt%) of stabilization agent addition, its compression ratio (CB value) diminishes gradually and (drops to 30% by 33.5%, about decline 3.5%), secondly (28.5% is dropped to by 31% for stabilization agent C, about decline 2.5%), moreover be that stabilization agent A of the present invention (drops to 30.8% by 33%, about decline 2.2%), in other words, add stabilization agent A of the present invention, and its addition is when 0.3 ~ 1.2wt% scope, the slippage of its compression ratio (CB value) is minimum.
Refer to shown in Fig. 7, Fig. 7 is stabilization agent of the present invention and the curve map of commercially available stabilization agent A and the corresponding moisture of B Different adding amount, from upper figure, the no matter kind of stabilization agent and the number (0.3 ~ 1.2wt%) of addition, along with the increase of retention time, the trend of its moisture rate of change is all identical (average moisture per hour about declines 0.1%), that is its slope is all identical, in other words, when three kinds of its additions of stabilization agent are within the scope of 0.3 ~ 1.2wt%, along with the increase (0 ~ 4hr) of retention time, rate of change all indifferences of its moisture.
Above, effect that the present invention reaches, lie in green sand mold after adding stabilization agent of the present invention, obviously can improve the hygrometric state compressive strength in green sand mold physical property, air permeability, compression ratio, surperficial stability and moisture etc. experiment parameter, to improve the quality of modeling sand, and can be used as the reference of joining sand, modeling, foundry goods defect analyses.
Although the present invention explains with a most preferred embodiment, be skillful in this those skilled in the art can not depart from the present invention spirit with category under do various multi-form change.Above illustrated embodiment, only in order to the present invention to be described, is not used to limit the scope of the invention.Such as do not disobey the present invention's various modifications of being engaged in of spirit or change, all belong to claim of the present invention.
Claims (10)
1., for adding a stabilization agent for green sand mold, it is characterized in that comprising:
One binding agent, it is the derivative of a phenol, and replaces hydrogen atom bond in addition with multiple functional group, and this binding agent accounts for 75% ~ 85% of gross weight; And
One additive, it contains various trace elements;
Wherein, the weight ratio of this binding agent and this additive is 4:1.
2. as claimed in claim 1 for adding the stabilization agent of green sand mold, it is characterized in that, those trace elements are for including sulphur (S), magnesium (Mg), sodium (Na), calcium (Ca).
3. as claimed in claim 1 for adding the stabilization agent of green sand mold, it is characterized in that, those functional groups include ketone group (Ketone group), aldehyde radical (Aldehyde group), ester cyclic group (Alicyclic group), elementary ethanol based (Primary alcohol group), secondary ethanol based (Secondary alcohol group) and thiazolinyl (Alkene group).
4. as claimed in claim 1 for adding the stabilization agent of green sand mold, it is characterized in that, the structure of this binding agent as shown in Figure 1.
5. as claimed in claim 1 for adding the stabilization agent of green sand mold, it is characterized in that, the percentage by weight of this binding agent is 81%.
6. as claimed in claim 1 for adding the stabilization agent of green sand mold, it is characterized in that, the percentage by weight of this additive is in 19%.
7. as claimed in claim 1 for adding the stabilization agent of green sand mold, it is characterized in that, this binding agent is added the solute of formation one brown powdery with additive.
8. as claimed in claim 6 for adding the stabilization agent of green sand mold, it is characterized in that, the bulk density of this solute is between 25 ~ 30g/cm
3.
9. as claimed in claim 6 for adding the stabilization agent of green sand mold, it is characterized in that, the pH value of this solute is between 5 ~ 6.
10. as claimed in claim 6 for adding the stabilization agent of green sand mold, it is characterized in that, the cold water solubility of this solute is 92%.
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CN1121328A (en) * | 1993-04-22 | 1996-04-24 | 福塞科国际有限公司 | A mould and a method for the casting of metals and refractory compositions for use therein |
CN1150070A (en) * | 1995-11-08 | 1997-05-21 | 花王株式会社 | Binder composition for casting mould, mould composition and mould manufacturing method |
JP2005169434A (en) * | 2003-12-09 | 2005-06-30 | Asahi Organic Chem Ind Co Ltd | Resin-coated sand for stacked mold |
CN101316665A (en) * | 2005-11-30 | 2008-12-03 | 花王株式会社 | Component for casting production and method for producing same |
CN101932394A (en) * | 2008-02-01 | 2010-12-29 | 阿什兰-苏德舍米-克恩费斯特有限公司 | The purposes of branched alkane diol carboxylic acid diesters in polyurethane-based foundry binders |
CN102753619A (en) * | 2010-02-11 | 2012-10-24 | 济南圣泉集团股份有限公司 | Phenolic resin binder composition |
-
2013
- 2013-07-31 CN CN201310328604.4A patent/CN104338892A/en active Pending
Patent Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
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CN1121328A (en) * | 1993-04-22 | 1996-04-24 | 福塞科国际有限公司 | A mould and a method for the casting of metals and refractory compositions for use therein |
TW270905B (en) * | 1993-12-28 | 1996-02-21 | Nippon Kyadikku Technology Service Kk | |
CN1150070A (en) * | 1995-11-08 | 1997-05-21 | 花王株式会社 | Binder composition for casting mould, mould composition and mould manufacturing method |
JP2005169434A (en) * | 2003-12-09 | 2005-06-30 | Asahi Organic Chem Ind Co Ltd | Resin-coated sand for stacked mold |
CN101316665A (en) * | 2005-11-30 | 2008-12-03 | 花王株式会社 | Component for casting production and method for producing same |
CN101932394A (en) * | 2008-02-01 | 2010-12-29 | 阿什兰-苏德舍米-克恩费斯特有限公司 | The purposes of branched alkane diol carboxylic acid diesters in polyurethane-based foundry binders |
CN102753619A (en) * | 2010-02-11 | 2012-10-24 | 济南圣泉集团股份有限公司 | Phenolic resin binder composition |
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