CN115464093A - High-temperature-resistant precoated sand with excellent fluidity - Google Patents
High-temperature-resistant precoated sand with excellent fluidity Download PDFInfo
- Publication number
- CN115464093A CN115464093A CN202210940907.0A CN202210940907A CN115464093A CN 115464093 A CN115464093 A CN 115464093A CN 202210940907 A CN202210940907 A CN 202210940907A CN 115464093 A CN115464093 A CN 115464093A
- Authority
- CN
- China
- Prior art keywords
- sand
- phenolic resin
- flow aid
- temperature
- stirring
- 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.)
- Granted
Links
- 239000004576 sand Substances 0.000 title claims abstract description 146
- KXGFMDJXCMQABM-UHFFFAOYSA-N 2-methoxy-6-methylphenol Chemical compound [CH]OC1=CC=CC([CH])=C1O KXGFMDJXCMQABM-UHFFFAOYSA-N 0.000 claims abstract description 39
- 239000005011 phenolic resin Substances 0.000 claims abstract description 39
- 229920001568 phenolic resin Polymers 0.000 claims abstract description 39
- 238000000034 method Methods 0.000 claims abstract description 35
- 239000003795 chemical substances by application Substances 0.000 claims abstract description 27
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 claims abstract description 22
- VKYKSIONXSXAKP-UHFFFAOYSA-N hexamethylenetetramine Chemical compound C1N(C2)CN3CN1CN2C3 VKYKSIONXSXAKP-UHFFFAOYSA-N 0.000 claims abstract description 15
- HBMJWWWQQXIZIP-UHFFFAOYSA-N silicon carbide Chemical compound [Si+]#[C-] HBMJWWWQQXIZIP-UHFFFAOYSA-N 0.000 claims abstract description 15
- 229910010271 silicon carbide Inorganic materials 0.000 claims abstract description 15
- 230000008569 process Effects 0.000 claims abstract description 14
- 239000011521 glass Substances 0.000 claims abstract description 13
- GUJOJGAPFQRJSV-UHFFFAOYSA-N dialuminum;dioxosilane;oxygen(2-);hydrate Chemical compound O.[O-2].[O-2].[O-2].[Al+3].[Al+3].O=[Si]=O.O=[Si]=O.O=[Si]=O.O=[Si]=O GUJOJGAPFQRJSV-UHFFFAOYSA-N 0.000 claims abstract description 12
- 229910052901 montmorillonite Inorganic materials 0.000 claims abstract description 12
- CJZGTCYPCWQAJB-UHFFFAOYSA-L calcium stearate Chemical compound [Ca+2].CCCCCCCCCCCCCCCCCC([O-])=O.CCCCCCCCCCCCCCCCCC([O-])=O CJZGTCYPCWQAJB-UHFFFAOYSA-L 0.000 claims abstract description 11
- 239000008116 calcium stearate Substances 0.000 claims abstract description 11
- 235000013539 calcium stearate Nutrition 0.000 claims abstract description 11
- 239000010881 fly ash Substances 0.000 claims abstract description 11
- 239000004408 titanium dioxide Substances 0.000 claims abstract description 11
- 230000008929 regeneration Effects 0.000 claims abstract description 9
- 238000011069 regeneration method Methods 0.000 claims abstract description 9
- 239000011324 bead Substances 0.000 claims abstract description 7
- 238000003756 stirring Methods 0.000 claims description 27
- 238000002360 preparation method Methods 0.000 claims description 13
- 238000002156 mixing Methods 0.000 claims description 12
- 239000004698 Polyethylene Substances 0.000 claims description 9
- -1 polyethylene Polymers 0.000 claims description 9
- 229920000573 polyethylene Polymers 0.000 claims description 9
- 239000000243 solution Substances 0.000 claims description 9
- RKISUIUJZGSLEV-UHFFFAOYSA-N n-[2-(octadecanoylamino)ethyl]octadecanamide Chemical compound CCCCCCCCCCCCCCCCCC(=O)NCCNC(=O)CCCCCCCCCCCCCCCCC RKISUIUJZGSLEV-UHFFFAOYSA-N 0.000 claims description 8
- 239000004005 microsphere Substances 0.000 claims description 6
- 229920005989 resin Polymers 0.000 claims description 4
- 239000011347 resin Substances 0.000 claims description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 4
- 239000000654 additive Substances 0.000 claims description 3
- 230000000996 additive effect Effects 0.000 claims description 3
- 239000004359 castor oil Substances 0.000 claims description 3
- 235000019438 castor oil Nutrition 0.000 claims description 3
- 239000011248 coating agent Substances 0.000 claims description 3
- 238000000576 coating method Methods 0.000 claims description 3
- 238000001816 cooling Methods 0.000 claims description 3
- ZEMPKEQAKRGZGQ-XOQCFJPHSA-N glycerol triricinoleate Natural products CCCCCC[C@@H](O)CC=CCCCCCCCC(=O)OC[C@@H](COC(=O)CCCCCCCC=CC[C@@H](O)CCCCCC)OC(=O)CCCCCCCC=CC[C@H](O)CCCCCC ZEMPKEQAKRGZGQ-XOQCFJPHSA-N 0.000 claims description 3
- 238000010438 heat treatment Methods 0.000 claims description 3
- 238000004806 packaging method and process Methods 0.000 claims description 3
- 239000007864 aqueous solution Substances 0.000 claims description 2
- 239000002131 composite material Substances 0.000 claims description 2
- WSFSSNUMVMOOMR-UHFFFAOYSA-N formaldehyde Substances O=C WSFSSNUMVMOOMR-UHFFFAOYSA-N 0.000 claims description 2
- 238000005266 casting Methods 0.000 abstract description 24
- 210000003462 vein Anatomy 0.000 abstract description 10
- 230000007547 defect Effects 0.000 abstract description 6
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 129
- 230000000052 comparative effect Effects 0.000 description 26
- 239000002994 raw material Substances 0.000 description 8
- 238000012360 testing method Methods 0.000 description 7
- 230000007423 decrease Effects 0.000 description 4
- 238000011068 loading method Methods 0.000 description 4
- 239000011230 binding agent Substances 0.000 description 3
- 238000010622 cold drawing Methods 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 239000000843 powder Substances 0.000 description 3
- 230000002950 deficient Effects 0.000 description 2
- 239000010437 gem Substances 0.000 description 2
- 229910001751 gemstone Inorganic materials 0.000 description 2
- 238000002844 melting Methods 0.000 description 2
- 230000008018 melting Effects 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 239000000377 silicon dioxide Substances 0.000 description 2
- VZSRBBMJRBPUNF-UHFFFAOYSA-N 2-(2,3-dihydro-1H-inden-2-ylamino)-N-[3-oxo-3-(2,4,6,7-tetrahydrotriazolo[4,5-c]pyridin-5-yl)propyl]pyrimidine-5-carboxamide Chemical compound C1C(CC2=CC=CC=C12)NC1=NC=C(C=N1)C(=O)NCCC(N1CC2=C(CC1)NN=N2)=O VZSRBBMJRBPUNF-UHFFFAOYSA-N 0.000 description 1
- LDXJRKWFNNFDSA-UHFFFAOYSA-N 2-(2,4,6,7-tetrahydrotriazolo[4,5-c]pyridin-5-yl)-1-[4-[2-[[3-(trifluoromethoxy)phenyl]methylamino]pyrimidin-5-yl]piperazin-1-yl]ethanone Chemical compound C1CN(CC2=NNN=C21)CC(=O)N3CCN(CC3)C4=CN=C(N=C4)NCC5=CC(=CC=C5)OC(F)(F)F LDXJRKWFNNFDSA-UHFFFAOYSA-N 0.000 description 1
- WZFUQSJFWNHZHM-UHFFFAOYSA-N 2-[4-[2-(2,3-dihydro-1H-inden-2-ylamino)pyrimidin-5-yl]piperazin-1-yl]-1-(2,4,6,7-tetrahydrotriazolo[4,5-c]pyridin-5-yl)ethanone Chemical compound C1C(CC2=CC=CC=C12)NC1=NC=C(C=N1)N1CCN(CC1)CC(=O)N1CC2=C(CC1)NN=N2 WZFUQSJFWNHZHM-UHFFFAOYSA-N 0.000 description 1
- DEXFNLNNUZKHNO-UHFFFAOYSA-N 6-[3-[4-[2-(2,3-dihydro-1H-inden-2-ylamino)pyrimidin-5-yl]piperidin-1-yl]-3-oxopropyl]-3H-1,3-benzoxazol-2-one Chemical compound C1C(CC2=CC=CC=C12)NC1=NC=C(C=N1)C1CCN(CC1)C(CCC1=CC2=C(NC(O2)=O)C=C1)=O DEXFNLNNUZKHNO-UHFFFAOYSA-N 0.000 description 1
- 229910001060 Gray iron Inorganic materials 0.000 description 1
- 230000002776 aggregation Effects 0.000 description 1
- 238000004220 aggregation Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000018109 developmental process Effects 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000011049 filling Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000005495 investment casting Methods 0.000 description 1
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N iron oxide Inorganic materials [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 1
- 239000000314 lubricant Substances 0.000 description 1
- 230000001050 lubricating effect Effects 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- NDLPOXTZKUMGOV-UHFFFAOYSA-N oxo(oxoferriooxy)iron hydrate Chemical compound O.O=[Fe]O[Fe]=O NDLPOXTZKUMGOV-UHFFFAOYSA-N 0.000 description 1
- 238000011056 performance test Methods 0.000 description 1
- 238000006116 polymerization reaction Methods 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000007528 sand casting Methods 0.000 description 1
- 238000009991 scouring Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
- 238000005200 wet scrubbing Methods 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
-
- 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
-
- 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
- B22C1/2233—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 obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
- B22C1/2246—Condensation polymers of aldehydes and ketones
- B22C1/2253—Condensation polymers of aldehydes and ketones with phenols
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W30/00—Technologies for solid waste management
- Y02W30/50—Reuse, recycling or recovery technologies
- Y02W30/91—Use of waste materials as fillers for mortars or concrete
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Mold Materials And Core Materials (AREA)
Abstract
The invention relates to the technical field of precoated sand, in particular to high-temperature-resistant precoated sand with excellent fluidity. The precoated sand comprises the following components: aggregate reclaimed sand, phenolic resin with a flow aid I dispersed on the surface, an anti-vein agent, urotropine, calcium stearate and a flow aid II; the reclaimed sand is produced by adopting a thermal method-wet method combined regeneration process; the anti-vein agent comprises silicon carbide, titanium dioxide, fly ash glass beads and montmorillonite. The invention adopts the reclaimed sand produced by the hot method-wet method combined regeneration process as the aggregate, and greatly improves the fluidity and the high temperature resistance of the precoated sand by adding the flow aid, the multi-component vein-resistant agent and the like, and effectively reduces the vein and sand-sticking defects of the casting.
Description
Technical Field
The invention relates to the technical field of precoated sand, in particular to high-temperature-resistant precoated sand with excellent fluidity.
Background
The precoated sand is prepared by using silica sand, ceramsite sand and jewel sand as raw sand, phenolic resin as a binder, urotropine as a curing agent and calcium stearate as a lubricant, has excellent filling property, collapsibility, surface smoothness and the like, and is widely used for producing precision castings such as automobile parts and the like. Along with the rapid development of the world mechanical industry, the quality requirements of assembly enterprises on castings are higher and higher, for example, once casting defects occur in the inner cavities of complex castings such as automobile engine cylinder bodies and cylinder covers, the castings cannot be polished and cleaned in the later period, and only can be discarded. The defects of fleshiness, sand sticking, vein and the like commonly seen in the inner cavity of the casting are closely related to the quality of the precoated sand, such as: the coated sand has insufficient fluidity, and the surface of the core is loose, so that the castings are fleshy and mechanically bonded with sand; the precoated sand has poor expansion performance at high temperature, and cracks on the surface of the sand core can cause vein of a casting; the precoated sand has poor high-temperature resistance, and sand grains are mutually fused with molten metal under the high-temperature condition, so that the casting is chemically bonded with sand.
The reclaimed sand is used sand which basically recovers the use performance in casting production and can be recycled, and 1-7 tons of used sand can be generated in each 1 ton of produced castings during sand casting, so that the used sand is recycled, the problems of poor flowability and insufficient high-temperature resistance commonly existing in the conventional precoated sand on the market are solved, and the method has important significance for improving the casting quality, improving the production efficiency and reducing the casting cost of enterprises.
Disclosure of Invention
Aiming at the technical problems in the prior art, the invention provides high-temperature-resistant precoated sand with excellent fluidity, which is characterized in that reclaimed sand produced by adopting a thermal method-wet method combined regeneration process is used as aggregate, and a flow assistant, a multi-component anti-vein agent and the like are added, so that the fluidity and the high-temperature resistance of the precoated sand are greatly improved, and the vein and sand sticking defects of castings are effectively reduced.
The technical purpose is realized by the following technical scheme:
the invention provides high-temperature-resistant precoated sand with excellent fluidity, which comprises the following components: aggregate reclaimed sand, phenolic resin with a flow aid I dispersed on the surface, an anti-vein agent, urotropine, calcium stearate and a flow aid II; the reclaimed sand is produced by adopting a thermal method-wet method combined regeneration process; the anti-vein agent comprises silicon carbide, titanium dioxide, fly ash glass beads and montmorillonite.
As a preferred embodiment of the present invention, the first flow aid comprises ethylene bis stearamide and polyethylene wax.
In a preferred embodiment of the present invention, the second flow aid is castor oil.
In a preferred embodiment of the present invention, based on 100 parts by weight of the reclaimed sand, the reclaimed sand contains 3 parts of phenolic resin with a first flow aid dispersed on the surface, 1 part of anti-vein agent, 0.1-0.3 part of urotropine solution, 0.05-0.10 part of calcium stearate and 0.05-0.10 part of a second flow aid, wherein the mass ratio of urotropine to water in the urotropine solution is 1:2.
in a preferred embodiment of the present invention, the preparation of the phenolic resin with the first flow aid dispersed on the surface thereof comprises the following steps: stirring and mixing 1.0-2.5 parts of phenolic resin, 0.2-1.0 part of polyethylene wax and 0.2-1.0 part of ethylene bis stearamide to obtain the high-performance phenolic resin.
As a preferred embodiment of the present invention, the preparation of the anti-vein agent comprises the steps of: stirring and mixing 0.1-0.5 part of silicon carbide, 0.1-0.5 part of titanium dioxide, 0.1-0.5 part of fly ash glass microsphere and 0.1-0.5 part of montmorillonite to obtain the silicon carbide/montmorillonite composite material.
More preferably, the preparation of the phenolic resin with the flow aid I dispersed on the surface comprises the following steps: stirring and mixing 2.0 parts of phenolic resin, 0.5 part of polyethylene wax and 0.5 part of ethylene bis stearamide to obtain the high-performance polyethylene glycol-formaldehyde resin; the preparation method of the anti-vein agent comprises the following steps: stirring and mixing 0.3 part of silicon carbide, 0.3 part of titanium dioxide, 0.3 part of fly ash glass microsphere and 0.1 part of montmorillonite to obtain the high-performance silicon carbide glass microsphere.
In a preferred embodiment of the present invention, based on 100 parts by weight of the reclaimed sand, 3 parts by weight of the phenolic resin having the first flow aid dispersed on the surface thereof, 1 part by weight of the anti-vein agent, 0.3 part by weight of the urotropine solution, 0.08 part by weight of the calcium stearate, and 0.08 part by weight of the second flow aid are used.
The invention also provides a preparation method of the high-temperature-resistant precoated sand with excellent fluidity, which comprises the following steps:
mixing and stirring the first flow aid and phenolic resin to obtain phenolic resin with the first flow aid dispersed on the surface;
heating the reclaimed sand produced by adopting a thermal method-wet method combined regeneration process to a preset temperature of 110-180 ℃, and putting the reclaimed sand into a sand mixer;
adding the phenolic resin with the surface dispersed with the flow additive I into a sand mixer, stirring at 120-180 ℃, and uniformly coating the phenolic resin on the surface of the reclaimed sand to form a phenolic resin film;
adding the anti-vein agent into a sand mixer, and stirring to cover the surface of the phenolic resin film;
adding the urotropine aqueous solution, stirring at 100-110 ℃, adding calcium stearate, and continuously stirring;
and finally adding a second flow aid, stirring, cooling and packaging.
Compared with the prior art, the invention has the beneficial effects that:
(1) The reclaimed sand produced by the combined reclamation process is used as the aggregate, the phase change expansion of the silica sand is eliminated in the hot process, the mud content of the aggregate is greatly reduced in the wet treatment process, the expansion resistance and the flow property of the aggregate are fundamentally improved, and the cost of the reclaimed sand is far lower than that of new sand, ceramsite sand and jewel sand;
(2) In the thermal method film covering process, the flow aid I is dispersed on the surface of the resin film, so that the melting point of the film covering sand is improved, the friction coefficient among sand particles is reduced, and the flow property of the film covering sand is effectively improved; the second flow aid can increase the lubricating effect among sand particles, and particularly can slow down the electrostatic aggregation of the precoated sand in winter, so that the fluidity of the precoated sand is further improved;
(3) The multi-component vein resistant agent is added, the silicon carbide not only can increase the deformability of the sand core at high temperature, but also can increase the heat transfer efficiency of the sand core, the thermal expansion stress is effectively released, the montmorillonite is highly dehydrated and shrunk at high temperature, the thermal expansion of the sand core can be effectively counteracted, and the vein of the casting is enhanced and improved in double functions; the titanium dioxide and the fly ash glass beads can improve the high temperature resistance of the sand core and can effectively reduce the defects of sand sticking and deformation of the casting.
Detailed Description
The present invention is further described in detail below with reference to specific examples so that those skilled in the art can more clearly understand the present invention.
The following examples are provided only for illustrating the present invention and are not intended to limit the scope of the present invention. All other embodiments obtained by a person skilled in the art based on the specific embodiments of the present invention without any inventive step are within the scope of the present invention.
In the examples of the present invention, all the raw material components are commercially available products well known to those skilled in the art, unless otherwise specified; in the examples of the present invention, unless otherwise specified, all the technical means used are conventional means well known to those skilled in the art.
Interpretation of terms and source of raw materials:
reclaimed sand: the reclaimed sand is used sand which is treated in casting production and basically recovers the service performance and can be recycled.
The thermal method-wet method combined regeneration process comprises the following steps: namely, the old sand is sequentially treated by hot roasting and wet scrubbing.
Inner covering sand washing: namely, the sand source is inner Mongolia, and the sand source is mined, scrubbed by a wet method and dried to obtain a finished product.
Thermal method reclaimed sand: namely, the used sand is subjected to a high-temperature roasting process to remove the residual binder on the surface of the used sand, so as to obtain the reclaimed sand.
Wet method reclaimed sand: namely, the used sand is scrubbed by a wet method to remove the residual binder on the surface of the used sand, and the reclaimed sand is obtained.
Example 1
The embodiment of the invention provides high-temperature-resistant precoated sand with excellent fluidity, which is prepared from the following raw materials in parts by weight:
the preparation process of the precoated sand of the embodiment is as follows:
(1) Adding the first flow aid and the phenolic resin into a high-speed stirrer, and uniformly mixing for 40s at a stirring speed of 720r/min to obtain the phenolic resin with the first flow aid dispersed on the surface;
adding silicon carbide, titanium dioxide, fly ash glass beads and montmorillonite into a high-speed stirrer for mixing for 40s at the stirring speed of 720r/min to obtain a uniformly mixed anti-vein agent;
(2) Heating the reclaimed sand produced by adopting a thermal method-wet method combined regeneration process to 150 ℃, and putting the reclaimed sand into a sand mixer;
(3) Adding the phenolic resin obtained in the step (1) into a sand mixer, stirring for 20s at 120-180 ℃, and uniformly coating the phenolic resin on the surface of the reclaimed sand to form a phenolic resin film;
(4) Putting the anti-vein agent obtained in the step (1) into a sand mixer, and stirring for 10s to uniformly wrap the anti-vein agent on the surface of the phenolic resin film;
(5) Adding urotropine water solution, stirring for 35s at 100-110 ℃;
(6) Adding calcium stearate, and stirring for 35s;
(7) Adding the second flow aid, stirring for 10s, discharging and cooling to obtain the finished product of precoated sand, and packaging.
Example 2
The embodiment of the invention provides high-temperature-resistant precoated sand with excellent fluidity, which is prepared from the following raw materials in parts by weight:
the preparation process of the precoated sand in the embodiment is basically the same as that in the embodiment 1.
Example 3
The embodiment of the invention provides high-temperature-resistant precoated sand with excellent fluidity, which is prepared from the following raw materials in parts by weight:
the preparation process of the precoated sand in the embodiment is basically the same as that in the embodiment 1.
Example 4
The embodiment of the invention provides high-temperature-resistant precoated sand with excellent fluidity, which is prepared from the following raw materials in parts by weight:
the preparation process of the precoated sand of the present example is substantially the same as that of example 1.
Comparative example 1
This comparative example provides precoated sand that differs from example 1 in that the aggregate was inner cover scouring sand.
Comparative example 2
This comparative example provides precoated sand that differs from example 1 in that the aggregate is thermally reclaimed sand.
Comparative example 3
This comparative example provides precoated sand that differs from example 1 in that the aggregate is wet-process reclaimed sand.
Comparative example 4
The present comparative example provides precoated sand that differs from example 1 in that no flow aid one is included.
Comparative example 5
This comparative example provides precoated sand that differs from example 1 in that no anti-veining agent was added.
Comparative example 6
This comparative example provides precoated sand that differs from example 1 in that no castor oil was added.
Comparative example 7
The comparative example provides precoated sand which is different from example 1 in that the anti-vein agent consists of the following raw materials in parts by weight: 0.3 part of silicon carbide, 0.3 part of titanium dioxide, 0.3 part of fly ash glass bead and 0.1 part of ferric oxide.
Performance test experiments:
(1) The physical and chemical properties of the precoated sand prepared in examples 1 to 4 and comparative examples 1 to 7 were measured, and the detection indexes and methods were as follows:
high temperature pressure resistance: and (3) preserving the heat of the precoated sand for 120s in a 230 ℃ mold to prepare a cylindrical test block with the diameter of 20mm and the height of 40 mm. And (3) carrying out vertical constant-temperature variable-pressure loading on the test block, wherein the temperature of the constant-temperature constant-pressure loading is 1000 ℃, the pressure is increased at the rate of 0.01MPa/m i n from 0MPa, and the pressure reached by crushing is recorded.
High temperature resistance time: and (3) preserving the heat of the precoated sand for 120s in a 230 ℃ mold to prepare a cylindrical test block with the diameter of 20mm and the height of 40 mm. And (3) carrying out vertical constant-temperature and constant-pressure loading on the test block, wherein the temperature of the constant-temperature and constant-pressure loading is 1000 ℃, the pressure is 0.2MPa, and the time required by crushing is recorded.
And testing the tensile strength and the fluidity according to the reference standard JB/T8583-2008.
Expansion ratio: and testing the expansion rate of the precoated sand at the high temperature of 1000 ℃ by using an SHH type resin sand high-temperature performance testing machine.
The results of the physicochemical properties of the precoated sands prepared in examples 1 to 4 and comparative examples 1 to 7 are shown in the following table:
as can be seen from the above table:
the precoated sand prepared in the examples 1 to 4 has better high-temperature pressure resistance, high-temperature time resistance, cold resistance strength, fluidity and expansion rate, and the comprehensive performance of the precoated sand is generally superior to that of the precoated sand prepared in the comparative examples 1 to 7;
when the inner covering washed sand is used for replacing the combined reclaimed sand as the aggregate, compared with the aggregate obtained in the embodiment 1, the obtained precoated sand has the advantages that the high-temperature resistant pressure is reduced by 32 percent, the high-temperature resistant time is reduced by 34 percent, the cold tensile strength is reduced by 19 percent, the fluidity is reduced by 8 percent, and the expansion rate is increased by 313 percent;
when the hot-method reclaimed sand is used for replacing combined reclaimed sand as aggregate, compared with the embodiment 1, the obtained precoated sand has the advantages that the high-temperature resistant pressure is reduced by 9 percent, the high-temperature resistant time is reduced by 5 percent, the cold-drawing strength is reduced by 21 percent, the fluidity is reduced by 13 percent, and the expansion rate is increased by 13 percent;
when wet-process reclaimed sand is used as aggregate instead of combined reclaimed sand, compared with the aggregate obtained in the embodiment 1, the obtained precoated sand has the advantages of 21% decline of high-temperature resistant pressure, 31% decline of high-temperature resistant time, 23% decline of cold-drawing strength, 5% decline of fluidity and 175% increase of expansion rate;
when no flow additive is added into the phenolic resin, compared with the phenolic resin in the example 1, the flowability of the obtained precoated sand is reduced by 21%;
when the anti-vein agent is not added, compared with the example 1, the obtained precoated sand has the advantages that the high-temperature resistant pressure is reduced by 36%, the high-temperature resistant time is reduced by 39%, and the expansion rate is increased by 550%;
when the flow aid II is not added, compared with the example 1, the flowability of the obtained precoated sand is reduced by 32%;
when the components of the anti-vein agent are changed, compared with example 1, the obtained coated sand has the advantages that the high-temperature resistant pressure is reduced by 7%, the high-temperature resistant time is reduced by 6%, the cold-drawing strength is reduced by 15%, the fluidity is reduced by 29%, and the expansion rate is increased by 125%.
(2) Preparing a gray cast iron diesel engine cylinder block of a certain model by adopting the precoated sand obtained in the embodiment and the comparative example, casting 100 blocks at the casting temperature of 1410 +/-20 ℃, and counting the sand sticking rate and the vein rate of the water jacket part, wherein the statistical result of the casting reject ratio is as follows:
| class of casting defect | Sand sticking% | The vein% |
| Example 1 | 1 | 2 |
| Example 2 | 1 | 1 |
| Example 3 | 2 | 2 |
| Example 4 | 1 | 2 |
| Comparative example 1 | 5 | 11 |
| Comparative example 2 | 5 | 5 |
| Comparative example 3 | 4 | 6 |
| Comparative example 4 | 11 | 3 |
| Comparative example 5 | 5 | 27 |
| Comparative example 6 | 22 | 6 |
| Comparative example 7 | 3 | 4 |
As can be seen from the above table, the precoated sand prepared in examples 1 to 4 of the present invention can reduce the sand sticking rate and the vein rate of castings and reduce the fraction defective of castings, compared with the precoated sand prepared in comparative examples 1 to 7.
Further research shows that when the following raw materials are adopted, the specification of the reclaimed sand is 50/100, and the concentration ratio of the three sieves is 80-85%; the polymerization speed of the phenolic resin is 20-60 s, and the softening point is 80-110 ℃; the softening point of the polyethylene wax powder is 102-108 ℃, the viscosity is 50-90, the fineness is 600-1200 meshes, and the bulk density is 0.90-1.00 g/cm 3 (ii) a The melting point of the ethylene bis stearamide powder is 141-146 ℃, and the fineness of the ethylene bis stearamide powder is 600-1200 meshes; the fineness of the silicon carbide is 270-600 meshes, the fineness of the titanium dioxide is 270-600 meshes, the fineness of the fly ash glass beads is 270-600 meshes, the fineness of the montmorillonite is 270-600 meshes, and the coated sand with excellent performance and capable of reducing the fraction defective of castings can be obtained.
It should be noted that the above examples are only for further illustration and description of the technical solution of the present invention, and are not intended to further limit the technical solution of the present invention, and the method of the present invention is only a preferred embodiment, and is not intended to limit the protection scope of the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (8)
1. The high-temperature-resistant precoated sand with excellent fluidity is characterized by comprising the following components: aggregate reclaimed sand, phenolic resin with a flow aid I dispersed on the surface, an anti-vein agent, urotropine, calcium stearate and a flow aid II;
the reclaimed sand is produced by adopting a thermal method-wet method combined regeneration process;
the anti-vein agent comprises silicon carbide, titanium dioxide, fly ash glass beads and montmorillonite.
2. The high-temperature-resistant precoated sand with excellent flowability according to claim 1, wherein the flow aid comprises ethylene bis-stearamide and polyethylene wax.
3. The high-temperature-resistant precoated sand with excellent flowability as claimed in claim 1, wherein the second flow aid is castor oil.
4. The high-temperature-resistant precoated sand with excellent fluidity according to any one of claims 1 to 3, wherein the weight of the reclaimed sand is 100 parts, the phenolic resin with the first flow aid dispersed on the surface is 3 parts, the anti-vein agent is 1 part, the urotropine solution is 0.1 to 0.5 part, the calcium stearate is 0.05 to 0.10 part, and the second flow aid is 0.05 to 0.10 part, wherein the mass ratio of urotropine to water in the urotropine solution is 1:2.
5. the high-temperature-resistant precoated sand with excellent fluidity according to claim 1 or 2, wherein the preparation of the phenolic resin with the flow aid I dispersed on the surface comprises the following steps: stirring and mixing 1.0-2.5 parts of phenolic resin, 0.2-1.0 part of polyethylene wax and 0.2-1.0 part of ethylene bis stearamide to obtain the high-performance phenolic resin;
and/or
The preparation method of the anti-vein agent comprises the following steps: stirring and mixing 0.1-0.5 part of silicon carbide, 0.1-0.5 part of titanium dioxide, 0.1-0.5 part of fly ash glass microsphere and 0.1-0.5 part of montmorillonite to obtain the silicon carbide/montmorillonite composite material.
6. The high-temperature-resistant precoated sand with excellent fluidity according to claim 5, wherein the preparation of the phenolic resin with the first flow aid dispersed on the surface thereof comprises the following steps: stirring and mixing 2.0 parts of phenolic resin, 0.5 part of polyethylene wax and 0.5 part of ethylene bis stearamide to obtain the high-performance polyethylene glycol-formaldehyde resin;
and/or
The preparation method of the anti-vein agent comprises the following steps: stirring and mixing 0.3 part of silicon carbide, 0.3 part of titanium dioxide, 0.3 part of fly ash glass microsphere and 0.1 part of montmorillonite to obtain the high-performance silicon carbide glass microsphere.
7. The high-temperature-resistant precoated sand with excellent fluidity according to claim 4, wherein the weight of the reclaimed sand is 100 parts, the phenolic resin with the first flow aid dispersed on the surface is 3 parts, the anti-vein agent is 1 part, the urotropine solution is 0.3 part, the calcium stearate is 0.08 part, and the second flow aid is 0.08 part.
8. The method for preparing high-temperature-resistant precoated sand having excellent fluidity according to any one of claims 1 to 7, comprising the steps of:
mixing and stirring the first flow aid and phenolic resin to obtain phenolic resin with the first flow aid dispersed on the surface;
heating the reclaimed sand produced by adopting a thermal method-wet method combined regeneration process to a preset temperature of 110-180 ℃, and putting the reclaimed sand into a sand mixer;
adding the phenolic resin with the surface dispersed with the flow additive I into a sand mixer, stirring at 120-180 ℃, and uniformly coating the phenolic resin on the surface of the reclaimed sand to form a phenolic resin film;
adding the anti-vein agent into a sand mixer, and stirring to cover the surface of the phenolic resin film;
adding the urotropine aqueous solution, stirring at 100-110 ℃, adding calcium stearate, and continuing stirring;
and finally adding a second flow aid, stirring, cooling and packaging.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210940907.0A CN115464093B (en) | 2022-08-07 | 2022-08-07 | High-temperature-resistant precoated sand with excellent fluidity |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210940907.0A CN115464093B (en) | 2022-08-07 | 2022-08-07 | High-temperature-resistant precoated sand with excellent fluidity |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN115464093A true CN115464093A (en) | 2022-12-13 |
| CN115464093B CN115464093B (en) | 2024-07-30 |
Family
ID=84367728
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210940907.0A Active CN115464093B (en) | 2022-08-07 | 2022-08-07 | High-temperature-resistant precoated sand with excellent fluidity |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115464093B (en) |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002316237A (en) * | 2001-04-20 | 2002-10-29 | Lignyte Co Ltd | Resin coated sand for shell mold |
| US20090114365A1 (en) * | 2007-11-07 | 2009-05-07 | Igc Technologies, Llc | Material used to combat thermal expansion related defects in high temperature casting processes |
| CN102836948A (en) * | 2011-06-22 | 2012-12-26 | 欧俊华 | Regenerated coated sand and preparation method thereof |
| JP2019063842A (en) * | 2017-10-04 | 2019-04-25 | 花王株式会社 | Aggregate composition for mold |
| CN110252942A (en) * | 2019-08-08 | 2019-09-20 | 承德北雁新材料科技有限公司 | Precoated sand and preparation method thereof |
| CN112275996A (en) * | 2020-10-29 | 2021-01-29 | 盐城仁创砂业科技有限公司 | Regeneration method of sand for large steel casting and high-temperature-resistant precoated sand prepared from regenerated sand |
| DE102019123374A1 (en) * | 2019-08-30 | 2021-03-04 | Bindur Gmbh | Process for the production of cores and molds using the sand molding process |
| CN113426942A (en) * | 2021-06-24 | 2021-09-24 | 南阳仁创砂业科技有限公司 | Method for preparing precoated sand for cast steel from recycled material |
-
2022
- 2022-08-07 CN CN202210940907.0A patent/CN115464093B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002316237A (en) * | 2001-04-20 | 2002-10-29 | Lignyte Co Ltd | Resin coated sand for shell mold |
| US20090114365A1 (en) * | 2007-11-07 | 2009-05-07 | Igc Technologies, Llc | Material used to combat thermal expansion related defects in high temperature casting processes |
| CN102836948A (en) * | 2011-06-22 | 2012-12-26 | 欧俊华 | Regenerated coated sand and preparation method thereof |
| JP2019063842A (en) * | 2017-10-04 | 2019-04-25 | 花王株式会社 | Aggregate composition for mold |
| CN110252942A (en) * | 2019-08-08 | 2019-09-20 | 承德北雁新材料科技有限公司 | Precoated sand and preparation method thereof |
| DE102019123374A1 (en) * | 2019-08-30 | 2021-03-04 | Bindur Gmbh | Process for the production of cores and molds using the sand molding process |
| CN112275996A (en) * | 2020-10-29 | 2021-01-29 | 盐城仁创砂业科技有限公司 | Regeneration method of sand for large steel casting and high-temperature-resistant precoated sand prepared from regenerated sand |
| CN113426942A (en) * | 2021-06-24 | 2021-09-24 | 南阳仁创砂业科技有限公司 | Method for preparing precoated sand for cast steel from recycled material |
Non-Patent Citations (1)
| Title |
|---|
| 魏金宇;张希俊;张方;: "碱酚醛树脂旧砂热法湿法联合再生工艺的研究", 热加工工艺, vol. 44, no. 23, 31 December 2015 (2015-12-31), pages 103 - 106 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN115464093B (en) | 2024-07-30 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110421113B (en) | Ceramsite sand prepared from old sand regeneration waste and precoated sand prepared from ceramsite sand | |
| CN110434278B (en) | High-temperature-resistant, low-gas-generation, low-expansion and easy-collapsibility precoated sand and preparation method thereof | |
| CN109277517B (en) | High-temperature-resistant ceramsite precoated sand for casting and preparation method thereof | |
| CN110076322B (en) | Ceramic reinforced steel-based wear-resistant composite material and preparation method thereof | |
| CN113426942B (en) | Method for preparing precoated sand for cast steel from recycled material | |
| CN108839640A (en) | A kind of high-speed EMUs grinding and preparation method thereof | |
| CN102134397B (en) | Synthetic brake shoe for urban railway vehicle and preparation method thereof | |
| CN1670113A (en) | Friction material for vehicles without asbestos and metal | |
| CN109332576A (en) | A kind of casting high silicon precoated sand of high temperature resistant and preparation method thereof | |
| CN115464093A (en) | High-temperature-resistant precoated sand with excellent fluidity | |
| CN108296476A (en) | A kind of 3D printing coremaking precoated sand | |
| CN103384653A (en) | Anti-veining additive for the production of casting molds and cores | |
| CN112430017A (en) | High-performance concrete prepared from waste materials and preparation method thereof | |
| CN1908038B (en) | Nano material brake slice and preparing process thereof | |
| CN114367629B (en) | High-temperature-resistant precoated sand and preparation method thereof | |
| CN116804107A (en) | Automobile brake disc and preparation method thereof | |
| CN113523180B (en) | 3D precoated sand and preparation method thereof | |
| CN110778629B (en) | Brake material containing halide and preparation method and application thereof | |
| CN108941440B (en) | Composite special sand for sand casting and preparation method thereof | |
| US2858589A (en) | Ductile iron castings and methods of making same | |
| CN113930045B (en) | A high-performance copper-free resin-based brake material prepared from foundry waste resin sand | |
| CN114367625B (en) | Refractory precoated sand and preparation method thereof | |
| CN108838332B (en) | Sand mold for large and medium-sized castings and preparation method thereof | |
| CN111019296A (en) | High-performance brake pad and processing method thereof | |
| CN108895102A (en) | A kind of preparation method of heat resistant and wear resistant type brake block |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |