CN104150924B - A kind of model casting legacy shell returns insulating and heating riser set and preparation method thereof - Google Patents
A kind of model casting legacy shell returns insulating and heating riser set and preparation method thereof Download PDFInfo
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- CN104150924B CN104150924B CN201410377968.6A CN201410377968A CN104150924B CN 104150924 B CN104150924 B CN 104150924B CN 201410377968 A CN201410377968 A CN 201410377968A CN 104150924 B CN104150924 B CN 104150924B
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Abstract
The present invention relates to a kind of insulating and heating riser set to be prepared by purgation: the first step: reclaim model casting legacy shell powder: by sorting, anhydrate, deironing, primary fragmentation, it is processed into particulate material, then through screening, secondary deironing, it is thus achieved that oversize and siftage, oversize and siftage are carried out classification process, obtaining and meet the refractory aggregate making riser buss, second step, with the model casting legacy shell preparation insulating and heating riser set reclaimed. The present invention can be greatly improved the utilization rate of metal, reduces production cost, and improves casting quality. Test shows, after casting solidification, the ability of normal sands riser feeding foundry goods is 6%��10%; The ability of insulated feeder feeding foundry goods is 16%��20%; And the feeding a casting ability of heat preservation rising head of the present invention is increased to 30%��36%.
Description
Technical field
The present invention relates to a kind of insulating and heating riser set and preparation method thereof, utilize and reclaim model casting legacy shell material making insulating and heating riser set. It is the model casting legacy shell of recovery to be made aggregate be used further to make insulating and heating riser set, solves the discarded shell material of model casting and directly discharges, contaminated environment, the drawback of land occupation.
Background technology
In castings production process, after liquid metal is poured into casting mold, cooling procedure occurs liquid contraction, if this contraction can not get compensating, to produce the defect such as shrinkage cavity or shrinkage porosite at cast-internal after solidification, this will influence whether the compactness of foundry goods, reduce mechanical performance, and causes waste product.
In order to obtain sound foundry goods, in actual production, rising head is set at the position of foundry goods final set foundry goods is carried out feeding, play the effect preventing shrinkage cavity and porosity, aerofluxus and collection slag. Along with the development of foundry engieering with to improving constantly that casting quality requires, insulation is bad or heating is not enough and acts on the shortcomings such as single owing to also existing for the sand mold riser buss of traditional handicraft, the insulating riser sleeve adopted or exothermic riser sleeve, the feeding requirement of foundry goods can not be met, therefore, development of new insulating and heating riser set is increasingly subject to the attention of foundry goods worker. Traditional Steel Casting Risers is sand mold, its heat conductivity is the same with casting mold, this just requires that Riser Dimensions is more much bigger than the foundry goods thermal center size of required feeding, and rising head really to supplement to the liquid volume of foundry goods be 6%��10%, so the consumption of rising head itself also can not be ignored. Research shows, after casting solidification, the ability of normal sands riser feeding foundry goods is 6%��10%, and the ability of insulated feeder feeding foundry goods is 16%��20%, and the feeding a casting ability of heat preservation rising head is increased to 30%��36%.
Insulating riser sleeve refers to the riser buss being mainly prepared from by insulation material, its action principle is that the heat accumulation function utilizing low thermal conductivity insulation material is to reduce the heat loss of riser buss inner metal liquid, thus extending the setting time of riser buss inner metal liquid, improve its feeding capacity to foundry goods. Mainly comprising of insulating riser sleeve generally comprises, insulation material, refractory aggregate, binding agent and some additional materials etc. The selection of composition material should follow the principle such as recovery that source is wide, nontoxic, free from environmental pollution, do not affect Modeling Material.
The refractory material majority of rising head is quartz sand on the market now, adds a small amount of floating bead, is generally rising head bigger than normal, lay particular stress on, too increases the cost of user.And the heat-insulating property of quartz sand is good not as mullite, bulk density is more than more than one times of discarded shell material. Even if that is other situations are constant, mullite is used to replace quartz sand rising head, minimum saving user's half cost. Floating bead, its density is only small, boring, and heat insulation property is best. But recovery rate is only small, particularly after total utilization of PCA, it is difficult to be collected separately, volcanic ash can also, but China is also difficult to collect.
In general steel-casting rising head, weight of liquid metal is no better than the weight of foundry goods own. Rising head is just discarded after using, and then the metal inside rising head also to cut away. Just can obtain the general shape of part, through ball blast, polishing, flaw detection, repair welding, the technique such as heat treatment, obtain satisfactory foundry goods. Owing to needing the electricity of about 700 degree in steel-casting fusion process per ton, it is meant that the waste of half molten steel or melt back, and a lot of metal includes alloy and can be burnt. So, reduce Riser Dimensions, by improving the performance of insulated feeder, it is possible to the effectively save electricity charge and iron loss. Reduce power consumption and also imply that the discharge reducing carbon dioxide, energy-conserving and environment-protective.
According to relevant information introduction, about 15,000,000 tons to 20,000,000 tons every year of the shell material whole nation is discarded in model casting. Currently for the process of these legacy shells, most enterprises take direct discharge, abandon or fill, pollute environment, land occupation. Mullite main in model casting legacy shell powder, the value of aluminium oxide is far longer than quartz sand, so manufacturer generally manufactures rising head without mullite, is nearly all with quartz sand for main manufacture rising head. It is contemplated that use discarded shell material to manufacture rising head, user can obtain following material benefit: rising head density is little, reduce purchase cost, high insulating effect, reduces Riser Dimensions, saves molten steel, namely power cost saving and burning loss of alloy, as reclaiming sand after rising head is discarded, it is possible to be effectively improved quartz sand performance, reduce acid atmosphere. Our cost recovery is exactly freight charges and processing cost, reaches to manufacture the granularity of rising head requirement, per ton cost only 350 yuan. Manufacturing insulating and heating riser, cost only 800 yuan, 2500 yuan, sale price of market is per ton.
In view of background above, we develop utilization and recycle model casting legacy shell material to make rising head.
Summary of the invention
It is an object of the invention to utilize recovery model casting legacy shell material to prepare insulating and heating riser set.
For realizing object above, the technical solution of the present invention is:
A kind of model casting legacy shell returns insulating and heating riser set and preparation method thereof, comprises the following steps:
The first step: reclaim model casting legacy shell powder: by sorting, anhydrate, deironing, primary fragmentation, is processed into particulate material, then through screening, secondary deironing, it is thus achieved that oversize and siftage, carries out classification process to oversize and siftage, obtaining and meet the refractory aggregate making riser buss, the step of employing is:
1, sorting
The legacy shell of recovery is sorted, removes impurity.
Investment casting enterprise, in shell processed (casting mold) process, generally to hang four to five serosity and powder, just can complete shell processed. Basic technical process is: wax-pattern-sprayed silicon colloidal sol-extension zirconium oxide (or aluminium oxide)-drying (above for each layer)-be stained with serosity-extensions zircon sand (or aluminium oxide)-dryings (being the second layer above)-be stained with serosity-extension mullite fine grained-drying (being third layer above)-be stained with serosity-extension mullite coarse granule-drying (being the 4th layer-hanging fluid-tight slurry-drying-autoclave dewaxing above).Can using zirconium oxide by above-mentioned ground floor and the second layer or aluminium oxide sorts, sorting can adopt manual sorting;
2, anhydrate
Legacy shell through classification being anhydrated processs, the legacy shell through classification is entered baking oven and does, temperature controls within 150 DEG C, removing nature moisture; Or by the legacy shell natural drying through classification, water content control can meet instructions for use within 4%.
3, deironing, primary fragmentation, is processed into particulate material
The legacy shell processed through water past carries out deironing, primary fragmentation processes, and makes the legacy shell processed through water past pass through the magnetic roller deironing on travelling belt, is re-fed into crusher in crushing, is processed into particulate material;
4, send into linear vibrating screen screening after the particulate material crush, being processed into, carry out secondary iron removal by magnetic separation simultaneously; By sieving and after secondary iron removal by magnetic separation, obtaining oversize one and siftage; Oversize order number is less than 30 orders, and siftage order number is 30-80 order;
5, refractoriness detection; The particulate material obtained is carried out refractoriness detection;
6, classification processes
Oversize and siftage are carried out classification process, obtain the particulate material meeting following order number and refractoriness requirement as the refractory aggregate manufacturing insulating and heating riser set:
For preparing the particulate material of insulating and heating riser set used by steel-casting, its refractoriness requires more than 1500 DEG C, and order number is 30 order 80 orders;
For preparing the particulate material of insulating and heating riser set used by ironcasting, its refractoriness should be greater than 1300 DEG C, and order number is 30-80 order;
For preparing the particulate material of insulating and heating riser set used by aluminum casting, its refractoriness should be greater than 800 DEG C, and order number is 16-30 order.
Second step, with the model casting legacy shell preparation insulating and heating riser set reclaimed
Method one: the refractory aggregate that the first step obtained, perlite, silica flour, fire clay, phenolic resin, thermite, water join and is sufficiently mixed uniformly in batch mixer, obtain the wet feed being blended, then wet feed is filled in mould, wet feed limit pre-consolidation is filled on limit, is then pressed into type, the demoulding is dried and obtained insulating and heating riser set. Refractory aggregate, perlite, silica flour, fire clay, phenolic resin, water ratio be: 60-80:10-20:10-20:5-10:5-10:10-20. Batch mixer incorporation time: 5-8 minute. Dry temperature 200-300 DEG C, drying time 2-3 hour.
Method two: with the ratio of 70:20:12.5:25:8.5:2, refractory aggregate, perlite, waste foam, waterglass, thermite, water are joined batch mixer respectively can mix homogeneously, the material being mixed uniformly is filled in mould, add and insert pore, pass into carbon dioxide to harden, after the demoulding, under naturalness or sunlight, further dehydration is dried again, to remove the moisture emitting in product, it is ensured that emit moisture less than 1%, obtain qualified product.
3. the comparison of the riser buss technology properties of unlike material
The performance indications of common several types insulating riser sleeve and application characteristic
The present invention can be greatly improved the utilization rate of metal, reduces production cost, and improves casting quality. Test shows, after casting solidification, the ability of normal sands riser feeding foundry goods is 6%��10%; The ability of insulated feeder feeding foundry goods is 16%��20%; And the feeding a casting ability of heat preservation rising head of the present invention is increased to 30%��36%.
Detailed description of the invention
Below in conjunction with detailed description of the invention, the present invention is further detailed explanation
Embodiment 1: a kind of model casting legacy shell returns prepares insulating and heating riser set and method thereof, comprises the following steps:
The first step:
1, sorting
The legacy shell of recovery is sorted, removes impurity.Investment casting enterprise, in shell processed (casting mold) process, generally to hang four to five serosity and powder, just can complete shell processed. Basic technical process is: wax-pattern-sprayed silicon colloidal sol-extension zirconium oxide (or aluminium oxide)-drying (above for each layer)-be stained with serosity-extensions zircon sand (or aluminium oxide)-dryings (being the second layer above)-be stained with serosity-extension mullite fine grained-drying (being third layer above)-be stained with serosity-extension mullite coarse granule-drying (being the 4th layer-hanging fluid-tight slurry-drying-autoclave dewaxing above). Using zirconium oxide by above-mentioned ground floor and the second layer or aluminium oxide sorts, sorting adopts manual sorting.
2, anhydrate
Legacy shell through classification being anhydrated processs, the legacy shell through classification is entered baking oven and does, temperature controls within 150 DEG C, removing nature moisture; Or by the legacy shell natural drying through classification, water content control can meet instructions for use within 4%.
3, deironing, primary fragmentation, is processed into particulate material
The legacy shell processed through water past carries out deironing, primary fragmentation processes, and makes the legacy shell processed through water past pass through the magnetic roller deironing on travelling belt, is re-fed into crusher in crushing, is processed into particulate material;
4, send into linear vibrating screen screening after the particulate material crush, being processed into, carry out secondary iron removal by magnetic separation simultaneously; By sieving and after secondary iron removal by magnetic separation, obtaining oversize one and siftage; Oversize order number 16-30 order (without 30 orders), siftage order number is 30-80 order;
Second step, with the model casting legacy shell preparation insulating and heating riser set reclaimed
Taking order number is that 16-30 order 60Kg reclaims model casting legacy shell particulate material, 10Kg perlite, 10Kg silica flour, 5Kg fire clay, 5Kg phenolic resin: 10, thermite 5Kg, water join in batch mixer, it is sufficiently mixed uniformly, batch mixer incorporation time: 5-8 minute. Obtaining the wet feed being blended, then wet feed is filled in mould, the pre-consolidation in wet feed limit is filled on limit, is then pressed into type, demoulding drying, dries temperature 200-300 DEG C, and namely drying time 2-3 hour obtains insulating and heating riser set used by aluminum casting.
The aluminum casting insulating and heating riser set main performance index prepared is:
1, density: 0.60g/cm3; 2, refractoriness: >=800 DEG C; 3, thermal conductivity: 0.25kcal/ (m h DEG C); 4, rupture strength: 1.5MPa; 5, sand removal and environmental pollution, riser buss Automatic-falling, pollution-free; 6, product yield 75%; .
Embodiment 2:
With embodiment 1, asynchronous: second step: the model casting legacy shell particulate material of 80Kg recovery, 20Kg perlite, 20Kg silica flour, 10Kg fire clay, 10Kg phenolic resin: 20Kg water.
The aluminum casting insulating and heating riser set main performance index prepared is:
1, density: 0.80g/cm3; 2, refractoriness: >=800 DEG C; 3, thermal conductivity: 0.20kcal/ (m h DEG C); 4, rupture strength: 2.5MPa; 6, product yield 70%.
Embodiment 3:
With embodiment 1, the difference is that second step: with the ratio of 75kg:22.5kg:8.5kg:24.5kg:8.5kg:2kg, refractory aggregate, perlite, waste foam, waterglass, thermite (aluminum and ferrum oxide part by weight are the mixture of 1:2.95), water are joined batch mixer respectively can mix homogeneously, the material being mixed uniformly is filled in mould, add and insert pore, passing into carbon dioxide to harden, after the demoulding, under naturalness or sunlight, further dehydration is dried again.
The steel-casting insulating and heating riser set main performance index prepared is:
1, density: 0.7g/cm3;2, refractoriness: >=1500 DEG C; 3, thermal conductivity: 0.23kcal/ (m h DEG C); 4, rupture strength: 2.0MPa; 5, product yield 73%.
Embodiment 4:
With embodiment 1, the difference is that: take the recovery model casting legacy shell particulate material that order number is 30-80 order.
The ironcasting insulating and heating riser set main performance index prepared is: 1, density: 0.7g/cm3; 2, refractoriness: >=1300 DEG C, 3, thermal conductivity: 0.23kcal/ (m h DEG C); 4, rupture strength: 2.0MPa; 5, product yield 73%.
Embodiment 5:
With embodiment 1, the difference is that: take the recovery model casting legacy shell particulate material that order number is 30-180 order.
The steel-casting insulating and heating riser set main performance index prepared is:
1, density: 0.80g/cm32, refractoriness: >=1500 DEG C, 3, thermal conductivity: 0.24kcal/ (m h DEG C); 4, rupture strength: 2.2MPa; 5, product yield 71%.
Embodiment 6:
With embodiment 2, the difference is that: take the recovery model casting legacy shell particulate material that order number is 30-80 order.
The steel-casting insulating and heating riser set main performance index prepared is:
1, density: 0.80g/cm3; 2, refractoriness: >=1500 DEG C; 3, thermal conductivity: 0.20kcal/ (m h DEG C); 4, rupture strength: 2.5MPa; 6, product yield 70%.
Embodiment 7: with embodiment 3, the difference is that: take the recovery model casting legacy shell particulate material that order number is 30-80 order.
The steel-casting insulating and heating riser set main performance index prepared is:
1, density: 0.7g/cm3; 2, refractoriness: >=1500 DEG C; 3, thermal conductivity: 0.23kcal/ (m h DEG C); 4, rupture strength: 2.0MPa; 6, product yield 73%.
Claims (4)
1. a method for insulating and heating riser set prepared by model casting legacy shell returns, comprises the following steps:
The first step: reclaim model casting legacy shell powder;
By sorting, anhydrating, deironing, primary fragmentation, be processed into particulate material, then through screening, secondary deironing, it is thus achieved that oversize and siftage, oversize and siftage carried out classification process, obtain and meet the refractory aggregate making riser buss, the step of employing is:
1) sorting
The legacy shell of recovery is sorted, removes impurity;
2) anhydrate
Legacy shell after sorting being anhydrated processs, legacy shell is entered baking oven and does, temperature controls within 150 DEG C, removing nature moisture, or by legacy shell natural drying, water content control is within 4%;
3) deironing, primary fragmentation, is processed into particulate material
The legacy shell processed through water past carries out deironing, primary fragmentation processes, and makes the legacy shell processed through water past pass through the magnetic roller deironing on travelling belt, is re-fed into crusher in crushing, is processed into particulate material;
4) screening, secondary deironing
Particulate material is sent into linear vibrating screen screening, carries out secondary iron removal by magnetic separation simultaneously; By sieving and after secondary iron removal by magnetic separation, obtaining oversize one and siftage; Oversize order number is more than 30 orders, and siftage order number is 30-80 order;
5) refractoriness detection; The particulate material obtained is carried out refractoriness detection;
6) classification processes
Oversize and siftage are carried out classification process, obtain the particulate material meeting following order number and refractoriness requirement as the refractory aggregate manufacturing insulating and heating riser set:
For preparing the particulate material of insulating and heating riser set used by steel-casting, its refractoriness requires more than 1500 DEG C, and order number is 30 order 80 orders;
For preparing the particulate material of insulating and heating riser set used by ironcasting, its refractoriness should be greater than 1300 DEG C, and order number is 30-80 order;
For preparing the particulate material of insulating and heating riser set used by aluminum casting, its refractoriness should be greater than 800 DEG C, and order number is 16-30 order;
Second step, prepares insulating and heating riser set by the model casting legacy shell particulate material reclaimed.
2. method according to claim 1, it is characterized in that: the model casting legacy shell particulate material that second step reclaims is prepared insulating and heating riser set and referred to: the refractory aggregate first step obtained, add perlite, silica flour, fire clay, thermite, phenolic resin and water are sufficiently mixed uniformly in batch mixer, obtain the wet feed being blended, then wet feed is filled in mould, the pre-consolidation in wet feed limit is filled on limit, it is then pressed into type, the demoulding is dried and is obtained insulating and heating riser set, refractory aggregate, perlite, silica flour, fire clay, the ratio of phenolic resin and water is: 60-80:10-20:10-20:5-10:5-10:10-20, batch mixer incorporation time: 5-8 minute, dry temperature 200-300 DEG C, drying time 2-3 hour.
3. method according to claim 1, it is characterized in that: the model casting legacy shell particulate material that second step reclaims is prepared insulating and heating riser set and referred to: by refractory aggregate, perlite, waste foam, waterglass, thermite and water join batch mixer mix homogeneously with the ratio of 60-75:20-25:10-15:25-30:5-10:1-2 respectively, the material being mixed uniformly is filled in mould, add and insert pore, pass into carbon dioxide to harden, after the demoulding, under naturalness or sunlight, further dehydration is dried again, to remove the moisture in rising head, ensure that the moisture of rising head is less than 1%, obtain insulating and heating riser set.
4. make by method described in claim 1 or 2 or 3 and obtain insulating and heating riser set.
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101279363A (en) * | 2008-05-15 | 2008-10-08 | 中国科学院金属研究所 | Method for inhibiting segregation in large-sized steel ingot |
| CN101433944A (en) * | 2008-12-19 | 2009-05-20 | 洛阳双瑞特种装备有限公司 | High-efficient exothermic riser sleeve for casting |
| CN102951916A (en) * | 2012-11-23 | 2013-03-06 | 柳薇 | Refractory aggregate for refractory brick manufactured through recycling investment casting old shell powder and processing method thereof |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101279363A (en) * | 2008-05-15 | 2008-10-08 | 中国科学院金属研究所 | Method for inhibiting segregation in large-sized steel ingot |
| CN101433944A (en) * | 2008-12-19 | 2009-05-20 | 洛阳双瑞特种装备有限公司 | High-efficient exothermic riser sleeve for casting |
| CN102951916A (en) * | 2012-11-23 | 2013-03-06 | 柳薇 | Refractory aggregate for refractory brick manufactured through recycling investment casting old shell powder and processing method thereof |
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