CN101804444A - Technology for casting nodular cast iron gearbox for railway passenger car bogie - Google Patents
Technology for casting nodular cast iron gearbox for railway passenger car bogie Download PDFInfo
- Publication number
- CN101804444A CN101804444A CN 200910300414 CN200910300414A CN101804444A CN 101804444 A CN101804444 A CN 101804444A CN 200910300414 CN200910300414 CN 200910300414 CN 200910300414 A CN200910300414 A CN 200910300414A CN 101804444 A CN101804444 A CN 101804444A
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- CN
- China
- Prior art keywords
- passenger car
- casting
- gearbox
- cast iron
- railway passenger
- 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
- 238000005266 casting Methods 0.000 title claims abstract description 32
- 229910001141 Ductile iron Inorganic materials 0.000 title claims abstract description 23
- 238000005516 engineering process Methods 0.000 title claims description 13
- 239000004576 sand Substances 0.000 claims abstract description 16
- 229910052845 zircon Inorganic materials 0.000 claims abstract description 10
- GFQYVLUOOAAOGM-UHFFFAOYSA-N zirconium(iv) silicate Chemical compound [Zr+4].[O-][Si]([O-])([O-])[O-] GFQYVLUOOAAOGM-UHFFFAOYSA-N 0.000 claims abstract description 10
- 239000011248 coating agent Substances 0.000 claims abstract description 8
- 238000000576 coating method Methods 0.000 claims abstract description 8
- 238000000465 moulding Methods 0.000 claims abstract description 6
- 229910052751 metal Inorganic materials 0.000 claims description 17
- 239000002184 metal Substances 0.000 claims description 17
- 230000000630 rising effect Effects 0.000 claims description 7
- 238000004140 cleaning Methods 0.000 claims description 6
- 235000013312 flour Nutrition 0.000 claims description 6
- 239000007799 cork Substances 0.000 claims description 4
- 238000002485 combustion reaction Methods 0.000 claims description 3
- ISWSIDIOOBJBQZ-UHFFFAOYSA-N phenol group Chemical group C1(=CC=CC=C1)O ISWSIDIOOBJBQZ-UHFFFAOYSA-N 0.000 claims description 3
- 230000002269 spontaneous effect Effects 0.000 claims description 3
- 238000003756 stirring Methods 0.000 claims description 3
- 239000003973 paint Substances 0.000 claims description 2
- 238000000034 method Methods 0.000 abstract description 8
- 239000011347 resin Substances 0.000 abstract description 6
- 229920005989 resin Polymers 0.000 abstract description 6
- 238000004519 manufacturing process Methods 0.000 abstract description 5
- 238000011049 filling Methods 0.000 abstract description 4
- 239000000843 powder Substances 0.000 abstract description 4
- 230000007547 defect Effects 0.000 abstract description 3
- 229910001338 liquidmetal Inorganic materials 0.000 abstract description 3
- 238000003723 Smelting Methods 0.000 abstract description 2
- 238000003754 machining Methods 0.000 abstract description 2
- 230000008646 thermal stress Effects 0.000 abstract 1
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 4
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 3
- YLQBMQCUIZJEEH-UHFFFAOYSA-N Furan Chemical compound C=1C=COC=1 YLQBMQCUIZJEEH-UHFFFAOYSA-N 0.000 description 3
- 125000003158 alcohol group Chemical group 0.000 description 3
- 230000002950 deficient Effects 0.000 description 3
- 230000003031 feeding effect Effects 0.000 description 3
- 238000005087 graphitization Methods 0.000 description 3
- 239000011148 porous material Substances 0.000 description 3
- 238000012360 testing method Methods 0.000 description 3
- 238000010923 batch production Methods 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- 238000009749 continuous casting Methods 0.000 description 2
- 238000001514 detection method Methods 0.000 description 2
- 239000000428 dust Substances 0.000 description 2
- 238000005429 filling process Methods 0.000 description 2
- 229910052742 iron Inorganic materials 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 238000003825 pressing Methods 0.000 description 2
- 229910001018 Cast iron Inorganic materials 0.000 description 1
- 208000037656 Respiratory Sounds Diseases 0.000 description 1
- 230000002929 anti-fatigue Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 239000011247 coating layer Substances 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 230000000875 corresponding effect Effects 0.000 description 1
- 238000000280 densification Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000003628 erosive effect Effects 0.000 description 1
- 238000007710 freezing Methods 0.000 description 1
- 230000008014 freezing Effects 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 229910002804 graphite Inorganic materials 0.000 description 1
- 239000010439 graphite Substances 0.000 description 1
- MHKWSJBPFXBFMX-UHFFFAOYSA-N iron magnesium Chemical compound [Mg].[Fe] MHKWSJBPFXBFMX-UHFFFAOYSA-N 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 239000003110 molding sand Substances 0.000 description 1
- 229910001562 pearlite Inorganic materials 0.000 description 1
- 239000011435 rock Substances 0.000 description 1
- 238000007493 shaping process Methods 0.000 description 1
- 238000007711 solidification Methods 0.000 description 1
- 230000008023 solidification Effects 0.000 description 1
- 239000007921 spray Substances 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 230000003746 surface roughness Effects 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- 229910000859 α-Fe Inorganic materials 0.000 description 1
Landscapes
- Mold Materials And Core Materials (AREA)
Abstract
The invention relates to all casting processes and smelting processes for a nodular cast iron gearbox of a railway passenger car bogie, in particular discloses a method for casting the nodular cast iron gearbox of the railway passenger car bogie, which is suitable for the manufacturing process of the gearbox of the railway passenger car bogie. By adopting a spherical unplugging type pouring cup, the filling time is controlled, so that the liquid metal is filled steadily, and the casting defects of inclusion, air holes, and the like are effectively controlled. By adopting resin sand molding, a zircon powder coating is brushed on the surface, so the surface quality of the castings is improved, and the surface machining allowance is reduced. By adopting low-temperature mold dismantling, the thermal stress of the castings is reduced, the casting deformation is reduced, the dimensional precision is improved, and the foundation for the mass production of the gearbox is laid. The method can solve the problems of the casting of the nodular cast iron pieces with a thin-wall complex structure, low temperature resistance of the gearbox, and the like.
Description
Technical field
The present invention relates to all casting process and the smelting process of nodular cast iron gearbox for railway passenger car bogie, a kind of casting method of nodular cast iron gearbox for railway passenger car bogie specifically, it is applicable to the manufacture process of railway passenger car bogie gear-box.
Background technology
The railway passenger car bogie gear-box is the plug-in critical component of passenger vehicle, is the carrier of driving shaft and bevel gear, bears dynamic load effect, is easy to generate fatigue.The gear-box work under bad environment, especially train moves at north of china in winter, need bear the test of low temperature.In order to guarantee railway operation safety, essential exploitation antifatigue, low temperature resistant gear-box foundry goods.
Summary of the invention
The object of the present invention is to provide a kind of technology for casting nodular cast iron gearbox for railway passenger car bogie, solve the problem such as low temperature resistant of the casting of thin wall complex structure nodular iron casting and gear-box.
Technical scheme of the present invention is:
A kind of technology for casting nodular cast iron gearbox for railway passenger car bogie, specific as follows:
(1) adopts phenolic sand molding and play core, help the shaping of complex structural member.Resin bonded sand mould intensity is big, and sand mold dimensional accuracy height can make casting section thickness even; The resin sand collapsibility is good, and the easy sand removal of foundry goods helps the cleaning of core sand in the labyrinth die cavity; Resin sand elevated temperature strength height, the refractoriness height helps the spray quality and improves.
(2) zircon flour coating of employing spheroidal graphite cast-iron special use helps surface quality of continuous castings and improves, and has reduced the Surface Machining surplus.Contain a certain amount of carbon dust (5-10wt%) in the zircon flour coating, play the surface action of protection sand mold.Zircon flour coating has improved the core erosion resistibility, has reduced the core drop, has improved cast(ing) surface fineness.Coating is alcohol-base paint, stirs during use, and during the brush first pass, igniting makes its spontaneous combustion, after the burning, and cleaning sand mold surface; Brush second time again, brush altogether 2 times, thickness is no more than 0.7mm (being generally 0.6-0.7mm).
(3) adopt feeder head with, feeder head with helps the spheroidal graphite cast-iron feeding.Spheroidal graphite cast-iron has graphite to separate out in process of setting, and graphitization expansion takes place.The rising head of spheroidal graphite cast-iron mainly plays the feeding effect when metal is in liquid state, when the foundry goods metal began to solidify, because graphitization expansion takes place, metal volume increased, if riser neck does not solidify, molten metal can be pushed back in the rising head.If the riser neck size is reduced, when the foundry goods metal freezing, riser neck also solidifies, the molten metal rising head that can not flow backwards back, and the feeding effect of rising head can obviously increase.This casting pressing port neck is of a size of Φ 25～40mm.
(4) adopt the sphere formula cup of drawing the cork, molten metal does not produce splash phenomena in cavity filling process, and the cup volume equates with foundry goods molten metal volume, makes molten metal short time in cup static, has guaranteed to be mingled with come-up, breeds fully, and nodularization is even; Adopt the cast of end leakage formula, it is steady to fill type, prevents from gas and be mingled with to be involved in, reduced be mingled with, defective such as pore.When cast, cup is watered expire earlier, cup pulls up spherical chock plug after watering and expiring, and molten metal charges into die cavity.
(5) adopt suitable poring rate and shake out time, help the foundry goods internal soundness and improve.Limit the duration of pouring, define poring rate exactly.The cast thin-wall part needs low temperature to water soon, and among the present invention, the speed of requirement is faster than routine.For fear of producing cold shut, require the duration of pouring can not be above 25 seconds.Shake out time is 12～14h, and shakeout temperature is 200-300 ℃, adopts low temperature shake out technology, and principal security foundry goods as-cast structure is a ferrite matrix, and less residual stress is arranged.Purpose is to make foundry goods under the condition of not heat-treating, and satisfies the mechanical property requirements of QT400-18AL, and is out of shape lessly, guarantees the dimensional accuracy in the process.
Beneficial effect of the present invention is as follows:
1. because the present invention has avoided the generation of molten iron splash phenomena, be mingled with come-up fully, liquid metal filling is steady, and no gas and oxide inclusion are involved in the molten metal, defective such as be difficult for causing crackle and loosen.
2. key of the present invention has been to solve the casting problem of thin wall complex structure nodular iron casting, has guaranteed the appearance quality and the inherent quality of foundry goods, and the batch process for later provides the technological guidance.
3. the present invention helps the production of high-quality gear-box for the batch process of railway passenger car bogie gear-box provides support.
4. the present invention can control surface roughness, guarantees that casting section thickness is even; Foundry goods inside does not have shrinkage cavity, loose, crack defect, guarantees the densification of foundry goods even tissue, and the foundry goods fuel permeation test did not leak in 6 hours.
The specific embodiment
Embodiment 1
Trial production nodular cast iron gearbox for railway passenger car bogie foundry goods, material QT400-18AL, weight 153kg, filling time 15s, pouring temperature 1420-1430 ℃.
Present embodiment railway passenger car bogie gear-box casting process scheme is as follows:
1) adopt the sphere formula cup of drawing the cork, molten metal does not produce splash phenomena in cavity filling process, and the cup volume equates with foundry goods molten metal volume.Adopt the cast of end leakage formula, it is steady to fill type, prevents from gas and be mingled with to be involved in, reduced be mingled with, defective such as pore.When cast, cup is watered expire earlier, cup pulls up spherical chock plug after watering and expiring, and molten metal charges into die cavity.
2) adopt the furane resins sand molding and play core, the special-purpose Zircon powder alcohol group dope of surface brush magnesium iron stirs during use, and during the brush first pass, igniting makes its spontaneous combustion, after the burning, and cleaning sand mold surface; Brush again second time, brush thickness of coating layer 0.6-0.7mm altogether 2 times.After moulding begins, mix furan resin-sand earlier, the resin addition accounts for 1.5wt%, and supporting curing agent addition accounts for 0.4wt%, and mixed molding sand is put into core box, plays core, makes drag box on the external form simultaneously.When playing core and playing type, reduce as far as possible and rock, guarantee the core dimensional accuracy.
Present embodiment Zircon powder alcohol group dope adopted is the Zircon powder alcohol group dope of the specifications and models ISOMOL230 that produces of Fushi section founding materials (China) Co., Ltd, wherein contain carbon dust and account for 6.9wt%.
3) rising head is selected feeder head with for use, and this casting pressing port neck is of a size of Φ 25～40mm.During cast, heat retaining and exothermal coverture 70-100mm is spread on the surface.
4) adopt low temperature shake out technology, shake out time is 12～14h, shake out in the time of 200-300 ℃, cleaning, blast, cooling naturally.
Because it is more reasonable that process program of the present invention is determined, the measures of being taked has all played corresponding effect, and its course of work and result are as follows:
1) adopts the formula cup of drawing the cork, stoped the intrusion of oxide inclusion effectively, make foundry goods interior, inclusion defect without any pore.
2) adopt phenolic sand molding, the brush zircon flour coating has improved surface quality, has guaranteed that casting section thickness is even.
3) adopt feeder head with, made full use of the characteristics of ductile iron solidification graphitization expansion, increased the feeding effect of rising head, guaranteed foundry goods dense structure.
4) adopt low temperature shake out technology, guarantee that casting stress is little, be out of shape little, minimizing foundry goods chilling tendency.
It is 230kg that present embodiment pours into the cast iron weight of liquid metal, and casting weight is 155kg, and filling time is 15s, observes casting process, finds the molten metal cleaning, rises steadily.Shake out after the 13h of cast back, surface quality of continuous castings is good.
Comparative example
Passenger car bogie iron casting overseas enterprise produced, and presentation quality is good, and size is accurate, but through carrying out flaw detection, found that the foundry goods internal soundness is not fine and close, had significantly loose.Through Mechanics Performance Testing, the low-temperature impact of discovery foundry goods has only 7J, does not reach standard-required.Tissue detection finds that its foundry goods organizes medium pearlite content higher, does not meet the requirement of organizing of QT400-18AL.
Claims (5)
1. a technology for casting nodular cast iron gearbox for railway passenger car bogie is characterized in that, and is specific as follows:
(1) adopts phenolic sand molding and play core, the zircon flour coating of surface brush spheroidal graphite cast-iron special use;
(2) rising head adopts feeder head with;
(3) adopt the sphere formula cup of drawing the cork, the cup volume equates with foundry goods molten metal volume;
(4) shake out time is 12～14h, and shakeout temperature is 200-300 ℃.
2. according to the described technology for casting nodular cast iron gearbox for railway passenger car bogie of claim 1, it is characterized in that: zircon flour coating is an alcohol-base paint, stirs during use, and during the brush first pass, igniting makes its spontaneous combustion, after the burning, and cleaning sand mold surface; Brush second time again, brush altogether 2 times, thickness is 0.6-0.7mm.
3. according to the described technology for casting nodular cast iron gearbox for railway passenger car bogie of claim 1, it is characterized in that: the riser neck of feeder head with is of a size of Φ 25～40mm.
4. according to the described technology for casting nodular cast iron gearbox for railway passenger car bogie of claim 1, it is characterized in that: the cast of employing end leakage formula, when cast, cup is watered expire earlier, cup pulls up spherical chock plug after watering and expiring, and molten metal charges into die cavity.
5. according to the described technology for casting nodular cast iron gearbox for railway passenger car bogie of claim 4, it is characterized in that: the duration of pouring can not be above 25 seconds.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200910300414 CN101804444B (en) | 2009-02-16 | 2009-02-16 | Technology for casting nodular cast iron gearbox for railway passenger car bogie |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200910300414 CN101804444B (en) | 2009-02-16 | 2009-02-16 | Technology for casting nodular cast iron gearbox for railway passenger car bogie |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN101804444A true CN101804444A (en) | 2010-08-18 |
| CN101804444B CN101804444B (en) | 2012-12-12 |
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| CN 200910300414 Active CN101804444B (en) | 2009-02-16 | 2009-02-16 | Technology for casting nodular cast iron gearbox for railway passenger car bogie |
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102407279A (en) * | 2011-11-29 | 2012-04-11 | 朱小英 | Method for preparing water-based coating for sand mold casting |
| CN102974772A (en) * | 2012-12-07 | 2013-03-20 | 齐齐哈尔轨道交通装备有限责任公司 | Shaft box mold of rail wagon bogie |
| CN103121081A (en) * | 2013-01-23 | 2013-05-29 | 辽宁福鞍重工股份有限公司 | Method for integrally casting heavy-duty high-horsepower diesel locomotive bogie |
| CN103128268A (en) * | 2013-01-17 | 2013-06-05 | 中国科学院金属研究所 | Method used for medium and low temperature mold dismantling of large-scale extra-thick plate blank |
| CN104084539A (en) * | 2014-06-30 | 2014-10-08 | 薛铁山 | Process for casting hanging bracket front-segment castings |
| CN104148579A (en) * | 2014-09-03 | 2014-11-19 | 李华山 | Resin sand-produced nodular cast iron paint and preparation method thereof |
| CN104785711A (en) * | 2015-04-30 | 2015-07-22 | 成都桐林铸造实业有限公司 | Casting process |
| CN106583661A (en) * | 2016-12-21 | 2017-04-26 | 常州新联铸业有限公司 | Manufacturing method for rear case body of gear case |
| CN112605340A (en) * | 2020-12-16 | 2021-04-06 | 中车戚墅堰机车车辆工艺研究所有限公司 | Nodular cast iron integral low-floor light rail gear box and casting method thereof |
Family Cites Families (3)
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| CN1069350C (en) * | 1997-05-19 | 2001-08-08 | 杨文财 | Production method of the millstone for ball grinding mill |
| CN1265914C (en) * | 2004-08-02 | 2006-07-26 | 中国科学院金属研究所 | Integral easting method of cast steel supporting roller |
| CN100343404C (en) * | 2006-01-11 | 2007-10-17 | 昆明嘉和泵业有限公司 | Sulfuric acid corrosion resistant alloy nodular cast iron materials |
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2009
- 2009-02-16 CN CN 200910300414 patent/CN101804444B/en active Active
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102407279A (en) * | 2011-11-29 | 2012-04-11 | 朱小英 | Method for preparing water-based coating for sand mold casting |
| CN102407279B (en) * | 2011-11-29 | 2013-09-11 | 宁波兴柯汽车新材料科技有限公司 | Method for preparing water-based coating for sand mold casting |
| CN102974772A (en) * | 2012-12-07 | 2013-03-20 | 齐齐哈尔轨道交通装备有限责任公司 | Shaft box mold of rail wagon bogie |
| CN102974772B (en) * | 2012-12-07 | 2015-02-04 | 齐齐哈尔轨道交通装备有限责任公司 | Shaft box mold of rail wagon bogie |
| CN103128268A (en) * | 2013-01-17 | 2013-06-05 | 中国科学院金属研究所 | Method used for medium and low temperature mold dismantling of large-scale extra-thick plate blank |
| CN103121081A (en) * | 2013-01-23 | 2013-05-29 | 辽宁福鞍重工股份有限公司 | Method for integrally casting heavy-duty high-horsepower diesel locomotive bogie |
| CN104084539A (en) * | 2014-06-30 | 2014-10-08 | 薛铁山 | Process for casting hanging bracket front-segment castings |
| CN104148579A (en) * | 2014-09-03 | 2014-11-19 | 李华山 | Resin sand-produced nodular cast iron paint and preparation method thereof |
| CN104785711A (en) * | 2015-04-30 | 2015-07-22 | 成都桐林铸造实业有限公司 | Casting process |
| CN106583661A (en) * | 2016-12-21 | 2017-04-26 | 常州新联铸业有限公司 | Manufacturing method for rear case body of gear case |
| CN112605340A (en) * | 2020-12-16 | 2021-04-06 | 中车戚墅堰机车车辆工艺研究所有限公司 | Nodular cast iron integral low-floor light rail gear box and casting method thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| CN101804444B (en) | 2012-12-12 |
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