CN106563765A - Low-ammonia environment-friendly resin coated sand - Google Patents
Low-ammonia environment-friendly resin coated sand Download PDFInfo
- Publication number
- CN106563765A CN106563765A CN201610959026.8A CN201610959026A CN106563765A CN 106563765 A CN106563765 A CN 106563765A CN 201610959026 A CN201610959026 A CN 201610959026A CN 106563765 A CN106563765 A CN 106563765A
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- ammonia
- coated sand
- friendly
- additive
- environment
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Classifications
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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
-
- 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
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- 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 discloses low-ammonia environment-friendly resin coated sand. Environment-friendly phenolic resin and non-ammonia active substance completely replace an urotropin curing agent which is used for a long time, so that micro-phase separation of a coated sand resin film is solved, basic requirements of curing speed and strength are guaranteed, and improvement on harmful gas-phase effluents in a core-making process of coated sand is realized. According to a test and large-scale application results in cast aluminum, cast iron and cast steel, the low-ammonia environment-friendly resin coated sand has the advantages that: compared with common resin coated sand, emission of odor gases such as ammonia gas is greatly reduced in a core-making process in case of ensuring performances of the novel ammonia-free environment-friendly coated sand unchanged; during casting, gas-phase organic pollutants are reduced, and key performances such as collapsibility, expansibility and high-temperature deformability can be obviously improved; and the low-ammonia environment-friendly resin coated sand is novel low-ammonia or ammonia-free environment-friendly coated sand with prospect.
Description
Technical field
The present invention relates to casting field, and in particular to a kind of low ammonia environment-friendly resin precoated sand.
Background technology
Coated sand typically refers to what is used for mould coremaking heat curing process, and aggregate is high temperature resistant inorganic natural stone
Sand or artificial sand, aggregate surface has wrapped the founding materialses of one layer of organic polymer resin.With the green ring of casting industry
The requirement more and more higher of guarantor property, due to the urotropine firming agent that precoated sand contains, in coremaking as resin is heating and curing
In the physical and chemical process of generation, the harmful substance of such as ammonia, serious ground contamination building ring can be in a large number discharged to working environment
Border, brings the ammonia of serious harm, 76ppm to have stimulation to the mucosa of people to the body of operator；When concentration reaches
During 300ppm, mucomembranous surface can sustain damage；If concentration is higher, the puffiness of the eyes, cough, dyspnea and vomiting can be caused
Etc. symptom, or even cause the disease such as bronchioless and alveolar hyperemia, edema, bleeding and emphysema, the ammonia of long-term low concentration
Chronic lung disease can be caused.By the concentration for detecting the coremaking workshop different parts ammonia of casting factory, it has been found that in car
Between exhaust outlet test ammonia concentration in 15-30ppm, in workshop core shooting region the ammonia density of 2m build-in tests be 35-150ppm, its
The concentration of its domain test ammonia is 20-120ppm, and mean concentration is 60ppm, and this concentration can be breathed for a long time far beyond people
Concentration.Therefore, develop on the basis of the precoated sand containing latent curing agent hexamethylenamine for commonly using now brand-new
The precoated sand product with low ammonia odor be technological progress certainty, reduce coremaking ammonia discharge, reduce to workers ' health
Impact.While being conducive to improving the environmental friendliness performance of coated sand, also technology is proposed to coated sand manufacturer
Improve and require.
The content of the invention
It is an object of the invention to provide a kind of low ammonia environment-friendly resin precoated sand, by improving raw material, has during reduction coremaking
The growing amount of evil ammonia.
To reach above-mentioned purpose, the technical scheme is that：Low ammonia environment-friendly resin precoated sand, aggregate, environment-friendly type phenolic aldehyde
Resin, additive A, non-Ammonia firming agent, hexamethylenamine, additive B, calcium powder.
Further improve, per the low ammonia environment-friendly resin precoated sands of 8000g, feature of environmental protection phenolic resin 0.8～3%, add water 0～
80g, non-amine curing agent 0.064～0.5%, hexamethylenamine 0～0.3%, additive B 0.002～0.02%, additive A
40～160g.
Further improve, the additive A is complex fire resistant additive.Additive A is powder functional material, main body material
Material is inorganic oxide and salt, organic functional material, carbon and carbon compound, surfactant etc., is by adding this
Row material can make low ammonia coated sand 15～40 minutes cores under 1000 DEG C of hot environments not rupture, than conventional resins overlay film
3～10 times of sand high temperature resistant time lengthening；Sharp coefficient of thermal expansion of the low ammonia coated sand under 1000 DEG C of hot environments can be made than passing
System coated sand reduces by 5～15%.
Further improve, the additive B is compound anti-sand caking additive.
During using above-mentioned technical proposal, because precoated sand produces the combustion of the main source for hexamethylenamine of flue gas in burning
Burn, the application of the Enviorment-protective Phenolic Resin by designing and developing out, using non-amine acitve organic matter as latent curing agent,
The urotropine firming agent for being used for a long time is substituted completely, the microfacies alloy theory, solidification power from macromolecular material
Theory sets out and designs a kind of brand-new precoated sand preparation technology, solves the micron-scale phase separation of precoated sand resin film, it is ensured that
The basic demand of curing rate and intensity, and realize the improvement of Harmful gas phase emission during the coremaking of precoated sand.Jing
Test and show in cast aluminium scale application result：It is new to ensure without ammonia environmental protection precoated sand compared with ordinary resin precoated sand
In the case that its performance is constant, the stench class gas ammonia emission during coremaking is greatly decreased, gas phase organic contamination during cast
Thing is reduced, and collapsibility significantly improves, and the expansion rate of precoated sand is reduced, and is a kind of rising new low ammonia or without ammonia ring
Protect precoated sand.
Specific embodiment
Low ammonia environment-friendly resin precoated sand, is made up of following raw material：Aggregate, Enviorment-protective Phenolic Resin, additive A, non-Ammonia
Firming agent, hexamethylenamine, additive B, calcium powder.
The preparation technology of low ammonia environment-friendly resin precoated sand, comprises the following steps：
The first step, will burn sand and is heated to 140-160 DEG C；
Second step, adds Enviorment-protective Phenolic Resin, additive A to be blended the time for 20-40s；
3rd step, then by sand temperature drop to 110-130 DEG C, add additive B and/or additive A, non-Ammonia firming agent and/
Or hexamethylenamine, it is blended 30-60s；
4th step, cooling of blowing a cold wind over blows a cold wind over the persistent period for 40-90s；
5th step, adds interleaving agent, is blended the time for 10-20s；
6th step, sieves, and is cooled to 30～60 DEG C in further cooler, and preferably 30～40；
7th step, sieves；
8th step, loads the woven bag containing plastic inner bag, obtains low ammonia environment-friendly resin precoated sand.
Per the low ammonia environment-friendly resin precoated sands of 8000g, feature of environmental protection phenolic resin 0.8～3%, add water 0～80g, and non-amine is consolidated
Agent 0.064～0.5%, hexamethylenamine 0～0.3%, additive B 0.002～0.02%, 40～160g of additive A.
The additive A is complex fire resistant additive.Additive A is powder functional material, and material of main part is inorganic oxygen
Compound and salt, organic functional material, carbon and carbon compound, surfactant etc., can be made by adding this series material
Low ammonia coated sand 15～40 minutes cores under 1000 DEG C of hot environments do not rupture, during than conventional resins precoated sand high temperature resistant
Between extend 3～10 times；Sharp coefficient of thermal expansion of the low ammonia coated sand under 1000 DEG C of hot environments can be made than conventional resins overlay film
Sand reduces by 5～15%.
Add different hexamethylenamine using preferred resin, at different temperatures the discharge of test solidification gas phase ammonia
Amount, and as the low ammonia precoated sand ammonia emission upper limit and the Appreciation gist of reduction amplitude.By test result table 1：
The ammonia amount (gas chromatography) of the different hexamethylenamine additions of table 1
From in terms of test result, reducing hexamethylenamine additional proportion can then reduce coremaking ammonia emission amount, when hexamethylenamine plus
Enter amount ratio be amount of resin 2% when, ammonia than tradition hexamethylenamine addition 14% when reduce by more than 60%.Therefore, reduce
Traditional latent curing agent hexamethylenamine is a material prescription process routes for preparing low ammonia precoated sand.
Table 2 is new without ammonia precoated sand and original product Character Comparison table
From with upper table data can be seen that it is new without ammonia precoated sand compared with original product ammonia reduce up to more than 90%,
(low 5.6%), remaining is better than original product or suitable with original product, explanation to other parameters in addition to real-time intensity is slightly below original product
New to replace original product for casting without ammonia precoated sand, its ammonia reduces highly significant, is entirely capable of making molding department ammonia
Concentration is less than 30mg/mL, so as to meet the regulation of China's labor protection.
Wherein, Enviorment-protective Phenolic Resin is belonging to thermoplastic phenolic resin, and the component of its chemical reaction is formaldehyde and phenol,
The amount of substance of common formaldehyde and phenol is than usually 1:1.1～1.25, such component proportion usually causes resins synthesis anti-
The imperfection answered so that contain a certain amount of free phenol in thermoplastic phenolic resin, in storage, mixing and solidification process middle reaches
From phenol meeting disperse in atmosphere, serious harm workers ' health simultaneously causes environmental pollution.The present invention adopts aldehyde phenol ratio for 1:1.05～
1.09 prescriptions, using the catalyst such as organic monoacid or organic monoacid zinc the phenolic resin of catalytic production is carried out.Such tree
Fat free phenol and free aldehyde are very low, and usual free phenol is less than 2%, and the aldehyde that dissociates is less than 0.5%.And other technique prescription productions
The free phenol of phenolic resin can reach 5% or so, and free aldehyde can reach 2% or so.
Non- Ammonia firming agent is a kind of with chemical reaction occurring with reactive modified phenolic resin functional group, does not contain amino
Organic active substance, they are included containing the functional group that can be reacted with phenolic hydroxyl group, such as：Carboxyl, epoxy radicals, cyano group, aldehyde
The organic compound or polymer of the functional groups such as base, carbonyl ether.This firming agent can be with phenolic resin weak acid environment
There is additive reaction in the phenolic hydroxyl group of phenolic resin, realize from linear molecule to the cancellated molecular conversion of build, be precoated sand
Core consolidation molding needs some strength to provide effectively support.
Firming agent employs the polycondensation addition technical method of polymer chemistry, using macromolecular material microfacies alloy into
Type mechanism, is connect by the group component that gel solidification can occur with reactive modified phenolic resin group contained in Novel curing agent
The reactions such as branch copolymerization, cross-linking crystal, under the premise of cure kinetics are ensured, realize reduction conventional resins precoated sand firming agent crow
Effect of the Lip river tropine amount ratio without the intensity of reduction coated sand.Ensure that the apparent curing rate of coated sand, strong
A large amount of stench gas gas-phase objects are discharged in the basic demand of degree, the meeting that life-time service is solved without or added less from the source of material
While urotropine firming agent, realizing reduces Harmful gas phase emission purpose in the coremaking of precoated sand and casting process.
Additive B is that one kind is gathered, adheres to pockets of functional material to avoid coated sand granular boundary from seeing.It
Including high molecular organic aliphatic acid soap (potash soap, soda soap, ammonium soaps, zinc soap etc.), fatty acid, paraffin, glycerol, vaseline
Deng, fatty acid amide (such as stearic amide) and fatty acid soaps and fatty acid amide mixture, silicone material (such as
Organic silicone oil, silicone oil, polydimethylsiloxane etc.), low molecular weight polyethylene, inorganic interleaving agent such as Pulvis Talci, mica powder and
Complex that potter's clay, white clay etc. are configured for key component etc.
Additive A is a kind of with inorganic oxide as basic aggregate, is compounded with the powder body material of organic surface active agent, nothing
Machine oxide includes that the oxide of the elements such as aluminum, sodium, potassium, calcium, ferrum, manganese, magnesium, barium, silicon, titanium, zirconium processes the particles of aggregates to be formed,
And be prepared from after surfactant process on surface.
Further improve, the additive is complex fire resistant additive.Additive is powder functional material, material of main part
It is inorganic oxide and salt, organic functional material, carbon and carbon compound, surfactant etc., by adding this series
Material can make low ammonia coated sand 15～40 minutes cores under 1000 DEG C of hot environments not rupture, than conventional resins precoated sand
3～10 times of high temperature resistant time lengthening；Sharp coefficient of thermal expansion of the low ammonia coated sand under 1000 DEG C of hot environments can be made than tradition
Coated sand reduces by 5～15%.
To reduce the discharge of coremaking free-phenol and free formaldehyde, technological temperature improves 3～20 DEG C, preferably 3～15 DEG C, most
Excellent is 5～10 DEG C, while being also beneficial to improve the fusing point and mulling knockability of low ammonia coated sand, finished product storage stability and strong
Degree.
Sand temperature is reduced in three steps using the cooling wind of low relative humidity, cooling rheumatism degree 10～60%, preferably 30～
45%, optimum is 30～35%.
Firming agent employs the polycondensation addition technical method of polymer chemistry, using macromolecular material microfacies alloy into
Type mechanism, is connect by the group component that gel solidification can occur with reactive modified phenolic resin group contained in Novel curing agent
The reactions such as branch copolymerization, cross-linking crystal, under the premise of cure kinetics are ensured, realize reduction conventional resins precoated sand firming agent crow
Effect of the Lip river tropine amount ratio without the intensity of reduction coated sand.Ensure that the apparent curing rate of coated sand, strong
A large amount of stench gas gas-phase objects are discharged in the basic demand of degree, the meeting that life-time service is solved without or added less from the source of material
While urotropine firming agent, realizing reduces Harmful gas phase emission purpose in the coremaking of precoated sand and casting process.
Under the premise of based on low ammonia coated sand Recipe basis, by using raising coated temperature, prolongation mulling week
Phase, moderate control rate of temperature fall, adjustment overlay film cooling method combine the new technology for making sand to be formed, and realize the low ammonia being prepared from
Coated sand has and measure at high proportion hexamethylenamine (12～18%) conventional resins precoated sand same intensity and fusing point with adding
Low ammonia coated sand product, and realize on this basis resin amount it is identical when, lower gas forming amount (reduces by 1～2 milli
Rise/gram), lower ammonia emission amount (coremaking ammonia emission amount is reduced than 30～95%, preferably 60～95%), lower dissociates
Phenol discharge capacity (coremaking free-phenol discharge capacity is reduced than 10～50%, preferably 30～50%), lower free formaldehyde discharge
Amount (coremaking free formaldehyde discharge capacity is reduced than 5～30%, preferably 10～30%), foundry goods is in 700～1550 DEG C of cast per public
Jin core reduces vapor phase contaminants VOCs and HAP total emission volumn 10～30% (preferably 15～30%).
Above-described is only the preferred embodiment of the present invention, it is noted that for a person skilled in the art,
Without departing from the inventive concept of the premise, some deformations and improvement can also be made, these should also be considered as the guarantor of the present invention
Shield scope, these are all without the effect and practical applicability for affecting the present invention to implement.The present invention omits technology, the shape of description
Shape, construction part are known technology.
Claims (3)
1. low ammonia environment-friendly resin precoated sand, it is characterised in that be made up of following raw material：Aggregate, Enviorment-protective Phenolic Resin, additive
A, non-Ammonia firming agent, hexamethylenamine, additive B, calcium powder
The preparation technology of low ammonia environment-friendly resin precoated sand according to claim 1, it is characterised in that per the low ammonia rings of 8000g
Guarantor's coated sand, feature of environmental protection phenolic resin 0.8～3%, add water 0～80g, non-amine curing agent 0.064～0.5%, Wu Luotuo
Product 0～0.3%, additive B 0.002～0.02%, 40～160g of additive A.
2. low ammonia environment-friendly resin precoated sand according to claim 1, it is characterised in that the additive A is to be combined resistance to height
Warm additive.
3. low ammonia environment-friendly resin precoated sand according to claim 1, it is characterised in that the additive B is to be combined anti-sand
Caking additive.
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| CN201610959026.8A CN106563765A (en) | 2016-11-03 | 2016-11-03 | Low-ammonia environment-friendly resin coated sand |
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| CN201610959026.8A CN106563765A (en) | 2016-11-03 | 2016-11-03 | Low-ammonia environment-friendly resin coated sand |
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| CN201610959026.8A Pending CN106563765A (en) | 2016-11-03 | 2016-11-03 | Low-ammonia environment-friendly resin coated sand |
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Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108160912A (en) * | 2017-12-29 | 2018-06-15 | 重庆长江造型材料（集团）股份有限公司 | A kind of preparation method of precoated sand additive |
| CN108160913A (en) * | 2017-12-29 | 2018-06-15 | 重庆长江造型材料（集团）股份有限公司 | A kind of precoated sand additive |
| CN108188339A (en) * | 2017-12-29 | 2018-06-22 | 重庆长江造型材料（集团）股份有限公司 | A kind of casting precoated sand for having anti-sintering and low expansion energy |
| CN108772534A (en) * | 2018-06-26 | 2018-11-09 | 重庆长江造型材料（集团）股份有限公司 | A kind of precoated sand and preparation method thereof |
| 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 |
| CN110883311A (en) * | 2019-12-31 | 2020-03-17 | 重庆长江造型材料（集团）股份有限公司 | Modification method of urotropine |
| CN110976751A (en) * | 2019-12-31 | 2020-04-10 | 重庆长江造型材料（集团）股份有限公司 | Precoated sand |
| CN111001754A (en) * | 2019-12-31 | 2020-04-14 | 重庆长江造型材料（集团）股份有限公司 | Preparation process of precoated sand |
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Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108160913B (en) * | 2017-12-29 | 2020-01-07 | 重庆长江造型材料（集团）股份有限公司 | Additive for precoated sand |
| CN108160913A (en) * | 2017-12-29 | 2018-06-15 | 重庆长江造型材料（集团）股份有限公司 | A kind of precoated sand additive |
| CN108188339A (en) * | 2017-12-29 | 2018-06-22 | 重庆长江造型材料（集团）股份有限公司 | A kind of casting precoated sand for having anti-sintering and low expansion energy |
| CN108160912A (en) * | 2017-12-29 | 2018-06-15 | 重庆长江造型材料（集团）股份有限公司 | A kind of preparation method of precoated sand additive |
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| CN108772534A (en) * | 2018-06-26 | 2018-11-09 | 重庆长江造型材料（集团）股份有限公司 | A kind of precoated sand and preparation method thereof |
| CN108772534B (en) * | 2018-06-26 | 2020-07-28 | 重庆长江造型材料（集团）股份有限公司 | Precoated sand and preparation method thereof |
| 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 |
| CN110883311A (en) * | 2019-12-31 | 2020-03-17 | 重庆长江造型材料（集团）股份有限公司 | Modification method of urotropine |
| CN110976751A (en) * | 2019-12-31 | 2020-04-10 | 重庆长江造型材料（集团）股份有限公司 | Precoated sand |
| CN111001754A (en) * | 2019-12-31 | 2020-04-14 | 重庆长江造型材料（集团）股份有限公司 | Preparation process of precoated sand |
| CN111001754B (en) * | 2019-12-31 | 2021-06-11 | 重庆长江造型材料（集团）股份有限公司 | Preparation process of precoated sand |
| CN110976751B (en) * | 2019-12-31 | 2021-07-16 | 重庆长江造型材料（集团）股份有限公司 | Precoated sand |
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Address after: 400709 No. 6 Wuxing Middle Road, Tongjiaxi Town, Beibei District, Chongqing Applicant after: Chongqing Changjiang moulding material (Group) Limited by Share Ltd Address before: 401320 Fengqi Road, Caijiagang Town, Beibei District, Chongqing Applicant before: Chongqing Changjiang moulding material (Group) Limited by Share Ltd |
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Application publication date: 20170419 |