CN110773708A - Large-scale thin wall superalloy casting gating system - Google Patents

Large-scale thin wall superalloy casting gating system Download PDF

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Publication number
CN110773708A
CN110773708A CN201911187116.XA CN201911187116A CN110773708A CN 110773708 A CN110773708 A CN 110773708A CN 201911187116 A CN201911187116 A CN 201911187116A CN 110773708 A CN110773708 A CN 110773708A
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China
Prior art keywords
casting
shaped
pouring
wedge
riser
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CN201911187116.XA
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CN110773708B (en
Inventor
孙长波
顾欣
李婧
潘波涛
尚伟
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AECC Shenyang Liming Aero Engine Co Ltd
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AECC Shenyang Liming Aero Engine Co Ltd
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B22CASTING; POWDER METALLURGY
    • B22CFOUNDRY MOULDING
    • B22C9/00Moulds or cores; Moulding processes
    • B22C9/22Moulds for peculiarly-shaped castings
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B22CASTING; POWDER METALLURGY
    • B22CFOUNDRY MOULDING
    • B22C9/00Moulds or cores; Moulding processes
    • B22C9/08Features with respect to supply of molten metal, e.g. ingates, circular gates, skim gates
    • B22C9/082Sprues, pouring cups
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B22CASTING; POWDER METALLURGY
    • B22CFOUNDRY MOULDING
    • B22C9/00Moulds or cores; Moulding processes
    • B22C9/08Features with respect to supply of molten metal, e.g. ingates, circular gates, skim gates
    • B22C9/088Feeder heads

Abstract

The invention relates to the technical field of precision casting of large thin-wall parts with jet nozzles at the tail of an aeroengine, in particular to a large thin-wall high-temperature alloy casting pouring system, which comprises a casting and a pouring gate and is of a group of two-part structure: the casting comprises an inner pouring channel, two cylindrical bosses and a plurality of inner risers which are arranged along the shape; the inner pouring channel, the inner riser and the casting are integrally formed, and the pouring gate, the cylindrical boss and the inner riser of the inner pouring channel are flush in the height direction; the casting runner is provided with a sprue cup, an exhaust passage, a main runner, a cross runner, a forming runner and two overlapped wedge-shaped risers, wherein a round platform-shaped riser or a wedge-shaped large riser is arranged at the middle position of the cross runner, and a plurality of small wedge-shaped risers are arranged on the forming runner.

Description

Large-scale thin wall superalloy casting gating system
Technical Field
The invention relates to the technical field of precision casting of large thin-wall parts with jet nozzles at the tail of an aeroengine, in particular to a pouring system for large thin-wall high-temperature alloy castings.
Background
The bottom plate of the expansion sealing sheet of the aero-engine of a certain model is a JG4246A alloy large thin-wall part, and the structure of the bottom plate has the characteristics of large length, thin wall, multiple ribs and large local thickness; the maximum length size is 505mm, the thinnest 1.0mm of bottom plate, and the length-thickness ratio reaches 505: 1. the alloy has a large mushy zone range, and metallurgical defects such as under-casting, cracks, looseness and the like are easily generated in the investment casting process.
Disclosure of Invention
The invention provides a large thin-wall high-temperature alloy casting pouring system which can effectively reduce the risk of metallurgical defects such as under-casting, cracks, looseness and the like and improve the casting qualification rate and the metallurgical quality of casting products.
The technical scheme of the invention is as follows:
the utility model provides a large-scale thin wall superalloy casting gating system, includes the foundry goods and waters, and the foundry goods symmetry sets up in watering both sides, forms a set of two structures:
inner pouring channels are arranged on the edge of the casting and the middle boss part along the shape, and meanwhile, the round head part of the casting is provided with a three-fork-shaped inner pouring channel; the middle boss part of the casting is provided with two cylindrical bosses along with the shape of the casting; a plurality of inner risers are uniformly arranged inwards along inner pouring channels on two sides of the edge of the casting; the inner pouring channel, the inner riser and the casting are integrally formed, and the pouring gate, the cylindrical boss and the inner riser of the inner pouring channel are flush in the height direction;
the pouring gate is provided with a pouring gate cup positioned at the top; the sprue cup is connected with a main sprue; a plurality of cross runners and two overlapped wedge-shaped risers are symmetrically arranged on two sides of the main runner, a truncated cone-shaped riser or a large wedge-shaped riser is arranged in the middle of each cross runner, the truncated cone-shaped risers are connected to a cylindrical boss of a casting, and the large wedge-shaped risers are connected to an inner runner of the middle boss part of the casting; the cross pouring gate and the overlapped wedge-shaped risers are connected with a forming pouring gate, and a plurality of small wedge-shaped risers are arranged on the forming pouring gate; two exhaust passages are arranged between the sprue cup and the forming runner.
The preferable scheme of the pouring system for the large thin-wall high-temperature alloy casting is that the width of the inner pouring channel is 2-8 mm, the height of the inner pouring channel is 2-9 mm away from the bottom plate of the edge of the casting, and the distance from the outermost side to the edge of the casting is 0.8-3 mm;
the preferable scheme of the pouring system for the large thin-wall high-temperature alloy casting is that the inner feeder is long-strip-shaped, the number of single sides is 5-14, the width is 8-30 mm, the length is 20-40 mm, the inner feeder extends to the edge of the casting, the width of the extension part is 14 mm-45 mm, and the symmetry axis of the inner feeder is a symmetry axis.
The preferable scheme of the pouring system for the large thin-wall high-temperature alloy casting is that the main pouring gate is a cuboid with the size of (15-30) mmX (30-55) mmX (400-700) mm or a cylinder with the size of phi 40-phi 90 mmX (400-700) mm.
The preferable scheme of the pouring system for the large thin-wall high-temperature alloy casting is that the cross runners are designed to be cuboid shapes with the sizes of (5-15) mmX (20-30) mmX (100-150) mm, and the number of the single sides is 6.
The preferable scheme of the pouring system for the large thin-wall high-temperature alloy casting is that the forming pouring gate is arranged in a horseshoe shape and comprises a semicircular ring part and two identical cuboid parts, the central radius of the semicircular ring part is 40-70 mm, the width of the semicircular ring part is 10-15 mm, the height of the semicircular ring part is 8-15 mm, and the length of the cuboid part is 400-700 mm;
according to the preferred scheme of the large thin-wall high-temperature alloy casting pouring system, the arrangement directions of the small wedge-shaped risers are not completely the same.
According to the preferable scheme of the large thin-wall high-temperature alloy casting pouring system, the size of the truncated cone-shaped riser is 25-45 mm in height, and the half angle is 3-10 degrees; the minimum section size of the wedge-shaped small riser is (3-7) mmx (18-35) mm, and the wedge angle is 10-16 degrees; the minimum section size of the wedge-shaped large riser is (15-30) mmx (5-20) mm, the wedge angle is 3-15 degrees, and the height is 18-45 mm; the minimum section size of the lapped wedge-shaped riser is (5-22) mmX (10-32) mm, the wedge angle is 8-16 degrees, and the height is 10-45 mm.
The invention has the beneficial effects that:
(1) molten metal can directly flow into a cross pouring gate and an overlapped wedge-shaped riser through a main pouring gate, and then the circular truncated cone riser, the wedge-shaped large riser and a U-shaped forming pouring gate directly play a role in filling a casting bottom plate, and the structure can effectively avoid the occurrence of under-casting by matching with proper preheating and pouring temperatures;
(2) molten metal flows into the internal riser and the internal pouring gate through the horseshoe-shaped forming pouring gate, so that the grooves and the ribs on the edge of the casting are fed, and the occurrence of under-casting and loosening of the edge of the casting is prevented;
(3) the short edge of the internal riser is extended to the edge of the casting, the symmetric axis of the internal riser is taken as the symmetric axis, and the height of the internal riser is flush with that of the internal riser, so that cracks at the position are eliminated;
(4) the inner casting height in the middle of the casting bottom plate is flush with the inner riser, so that the main rib of the casting can be effectively fed, and the loose production of the position is prevented.
(5) The casting yield of the product is improved, the master alloy material for production is saved, and the production cost is reduced.
Drawings
FIG. 1 is a schematic view of a large thin-wall superalloy casting gating system
FIG. 2 is a schematic view showing the arrangement of an ingate, an ingate and a cylindrical boss
FIG. 3 is a partial view of the ingate and the ingate
FIG. 4 is a schematic view of a forming runner
FIG. 5 is a bottom view of a large thin-walled superalloy casting
FIG. 6 is a front view of a large thin-walled superalloy casting
In the figure: 1-casting; 2-pouring channel; 3-inner pouring channel; 4-a cylindrical boss; 5-internal riser; 6-pouring cup; 7-main pouring channel; 8-horizontal pouring channel; 9-overlapping the wedge-shaped riser; 10-truncated cone-shaped risers; 11-wedge-shaped large riser; 12-forming pouring channel; 13-a small wedge-shaped riser; 14-an exhaust passage.
Detailed Description
As shown in FIGS. 5 to 6, the outline dimensions of the large thin-walled superalloy casting are 500.5mm × 100 mm. The thickness of the bottom plate is divided into a front end and a rear end. The thickness of the front end bottom plate is 0.6 mm-0.8 mm, and the thickness of the rear end bottom plate is 0.8 mm-1 mm. The middle part is a bearing main rib with the thickness of about 2.5 mm-3.8 mm, and pin shaft seats are arranged at the positions distributed 2. The integral structure is that the longitudinal and transverse staggered thickness of the ribs is 1.5 mm-3 mm, the arc bottom plate at the front end is a plane, the middle of the rest part is a plane, the two sides are lap joint surfaces with a certain angle, and the concrete pouring system design is carried out according to the casting as an example.
As shown in figures 1-4, the pouring system for the large thin-wall high-temperature alloy castings comprises a casting 1 and a pouring gate 2, wherein the casting 1 is symmetrically arranged on two sides of the pouring gate 2 to form a group of two-piece structures:
inner pouring channels 3a are arranged at the edges of the castings and the middle boss part along the shape, meanwhile, inner pouring channels 3b of a three-fork structure are arranged at the round head part of the castings, the width of each inner pouring channel 3 is 5mm, the height of each inner pouring channel is 2mm away from the bottom plate of the edge of the casting, and the distance between the outermost side and the edge of the casting is 1.5 mm; the middle boss part of the casting is provided with two cylindrical bosses 4 along with the shape of the casting; the casting method comprises the following steps that inner risers 5 are uniformly arranged inwards along inner pouring channels on two sides of the edge of a casting, the number of single sides is 8, the shape of each inner riser is a long strip, the width of each inner riser is 8mm, the length of each inner riser is 20mm, each inner riser 5 extends to the edge of the casting, the width of each extending part is 10mm, and the symmetry axis of each inner riser is a symmetry axis; the inner pouring channel 3, the inner riser 5 and the casting are integrally formed, and a pouring gate of the inner pouring channel 3, the cylindrical boss 4 and the inner riser 5 are flush in the height direction;
the pouring gate 2 is provided with a pouring gate cup 6 positioned at the top; the sprue cup 6 is connected with a main sprue 7, and the main sprue 7 is a cuboid with the size of 25mm multiplied by 45mm multiplied by 560 mm; the main pouring gate 7 is symmetrically provided with 12 cross pouring gates 8 and two overlapped wedge-shaped risers 9 at two sides, the number of the single sides of each cross pouring gate 8 is 6, the cross pouring gates are designed to be in a cuboid shape with the size of 10mm multiplied by 25mm multiplied by 120mm, the minimum cross-sectional size of the overlapped wedge-shaped risers is 14mm multiplied by 30mm, the wedge angle is 10mm, and the height is 10 mm; a truncated cone-shaped riser 10 or a wedge-shaped large riser 11 is arranged in the middle of the cross gate 8, the size of the truncated cone-shaped riser 10 is 35mm in height, and the radius of a small circle with a half angle of 5 degrees is 10 mm; the minimum section size of the wedge-shaped big riser 11 is 10mm multiplied by 25mm, the wedge angle is 12 degrees, and the height is 35 mm; the round platform-shaped risers 10 are connected to the cylindrical bosses 4 of the castings 1, and the wedge-shaped large risers 11 are connected to the inner pouring channels 3b of the boss parts in the middles of the castings 1; the cross pouring gate 8 and the overlapped wedge-shaped risers 9 are connected with a forming pouring gate 12, and 21 small wedge-shaped risers 13 are arranged on the forming pouring gate 12; two exhaust passages 14 are arranged between the sprue cup 6 and the forming pouring gate 12.
The forming pouring gate 12 is in a horseshoe shape and comprises a semicircular ring part 12a and two identical cuboid parts 12b, the central radius of the semicircular ring part is 40mm, the width of the semicircular ring part is 13mm, the height of the semicircular ring part is 10mm, and the length of the cuboid part is 475 mm; the arrangement directions of the small wedge-shaped risers 13 are not completely the same, wherein 3 small wedge-shaped risers 13a are symmetrically arranged along the center of the semicircular part 12a, the cuboid part 12b is provided with 2 vertical small wedge-shaped risers 13b and 16 transverse small wedge-shaped risers 13c, the small wedge-shaped risers 13c are in one-to-one correspondence with the internal risers 5, the minimum cross-sectional dimension of the small wedge-shaped risers 13 is 5 multiplied by 18mm, and the four-side wedge angle is 11 degrees.
And designing moulds for all parts of the pouring system with the sizes, and pressing wax moulds respectively to complete a group of two-piece module combination. And (3) removing oil, preparing a shell, pouring, removing the shell and removing a pouring system from the module to obtain the casting.

Claims (8)

1. The utility model provides a large-scale thin wall superalloy casting gating system which characterized in that, the gating system includes the foundry goods and waters, and the foundry goods symmetry sets up in watering both sides, forms a set of two structures:
inner pouring channels are arranged on the edge of the casting and the middle boss part along the shape, and meanwhile, the round head part of the casting is provided with a three-fork-shaped inner pouring channel; the middle boss part of the casting is provided with two cylindrical bosses along with the shape of the casting; a plurality of inner risers are uniformly arranged inwards along inner pouring channels on two sides of the edge of the casting; the inner pouring channel, the inner riser and the casting are integrally formed, and the pouring gate, the cylindrical boss and the inner riser of the inner pouring channel are flush in the height direction;
the pouring gate is provided with a pouring gate cup positioned at the top; the sprue cup is connected with a main sprue; a plurality of cross runners and two overlapped wedge-shaped risers are symmetrically arranged on two sides of the main runner, a truncated cone-shaped riser or a large wedge-shaped riser is arranged in the middle of each cross runner, the truncated cone-shaped risers are connected to a cylindrical boss of a casting, and the large wedge-shaped risers are connected to an inner runner of the middle boss part of the casting; the cross pouring gate and the overlapped wedge-shaped risers are connected with a forming pouring gate, and a plurality of small wedge-shaped risers are arranged on the forming pouring gate; two exhaust passages are arranged between the sprue cup and the forming runner.
2. The large-scale thin-wall superalloy casting gating system of claim 1, wherein the inner runner is 2mm to 8mm wide, 2mm to 9mm high from a bottom plate of the casting edge, and 0.8mm to 3mm far from the casting edge at the outermost side.
3. The large-scale thin-wall superalloy casting pouring system according to claim 1, wherein the inner feeder is long-strip-shaped, the number of single sides is 5-14, the width is 8 mm-30 mm, the length is 20 mm-40 mm, the inner feeder extends to the edge of the casting, the width of the extending part is 10 mm-45 mm, and the symmetry axis of the inner feeder is a symmetry axis.
4. A large-scale thin-wall superalloy casting gating system according to claim 1, wherein the main runner is a cuboid or a cylinder with a size of phi 40 to phi 90 mm x (400 to 700) mm, and the size of the main runner is (15 to 30) mm x (30 to 55) mm x (400 to 700) mm.
5. A large thin-walled superalloy casting gating system as claimed in claim 1, wherein the runner is designed to be (5-15) mmx (20-30) mmx (100-150) mm cuboid in size and 6 on a single side.
6. The large thin-wall high-temperature alloy casting pouring system as claimed in claim 1, wherein the forming runner is in a horseshoe shape and comprises a semicircular ring part and two identical cuboid parts, the central radius of the semicircular ring part is 40 mm-70 mm, the width of the semicircular ring part is 10 mm-15 mm, the height of the semicircular ring part is 8 mm-15 mm, and the length of the cuboid part is 400 mm-700 mm.
7. A large thin-walled superalloy casting gating system as claimed in claim 1, wherein the small tapered risers are not oriented in the same direction.
8. The large-scale thin-wall superalloy casting gating system of claim 1, wherein the size of the truncated cone-shaped riser is 25mm to 45mm high, and the half angle is 3 ° to 10 °; the minimum section size of the wedge-shaped small riser is (3-7) mmx (18-35) mm, and the wedge angle is 10-16 degrees; the minimum section size of the wedge-shaped large riser is (15-30) mmx (5-20) mm, the wedge angle is 3-15 degrees, and the height is 18-45 mm; the minimum section size of the lapped wedge-shaped riser is (5-22) mmX (10-32) mm, the wedge angle is 8-16 degrees, and the height is 10-45 mm.
CN201911187116.XA 2019-11-28 2019-11-28 Large-scale thin wall superalloy casting gating system Active CN110773708B (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113263140A (en) * 2020-09-04 2021-08-17 浙江泰能机械制造有限公司 Bottom and middle cross gate and valve pouring, middle way and middle way flange feeding system
CN113664162A (en) * 2021-08-19 2021-11-19 中国航发沈阳黎明航空发动机有限责任公司 Large-scale thin wall foundry goods gating system more than 650mm of length

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Publication number Priority date Publication date Assignee Title
CN104353784A (en) * 2014-10-31 2015-02-18 沈阳黎明航空发动机(集团)有限责任公司 Precision casting method for complex thin-wall structural member framework of high-temperature alloy cavity
CN204276817U (en) * 2014-11-10 2015-04-22 沈阳黎明航空发动机(集团)有限责任公司 A kind of bend pipe casting portion running gate system mould
CN105312504A (en) * 2015-11-04 2016-02-10 沈阳黎明航空发动机(集团)有限责任公司 High temperature alloy thin-wall annular casting pouring system and manufacturing method
RU159399U1 (en) * 2015-02-18 2016-02-10 Публичное акционерное общество "КАМАЗ" TIERING GATE SYSTEM FOR CASTING PRODUCTION
CN105436419A (en) * 2015-12-03 2016-03-30 内蒙古北方重工业集团有限公司 Space curve type casting anti-deformation box cage structure and machining method
CN205324642U (en) * 2015-11-30 2016-06-22 保定风帆精密铸造制品有限公司 A the gating system for high -speed railway insulator gold utensil precision casting

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104353784A (en) * 2014-10-31 2015-02-18 沈阳黎明航空发动机(集团)有限责任公司 Precision casting method for complex thin-wall structural member framework of high-temperature alloy cavity
CN204276817U (en) * 2014-11-10 2015-04-22 沈阳黎明航空发动机(集团)有限责任公司 A kind of bend pipe casting portion running gate system mould
RU159399U1 (en) * 2015-02-18 2016-02-10 Публичное акционерное общество "КАМАЗ" TIERING GATE SYSTEM FOR CASTING PRODUCTION
CN105312504A (en) * 2015-11-04 2016-02-10 沈阳黎明航空发动机(集团)有限责任公司 High temperature alloy thin-wall annular casting pouring system and manufacturing method
CN205324642U (en) * 2015-11-30 2016-06-22 保定风帆精密铸造制品有限公司 A the gating system for high -speed railway insulator gold utensil precision casting
CN105436419A (en) * 2015-12-03 2016-03-30 内蒙古北方重工业集团有限公司 Space curve type casting anti-deformation box cage structure and machining method

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113263140A (en) * 2020-09-04 2021-08-17 浙江泰能机械制造有限公司 Bottom and middle cross gate and valve pouring, middle way and middle way flange feeding system
CN113263140B (en) * 2020-09-04 2022-11-15 浙江泰能机械制造有限公司 Bottom, middle cross pouring gate and valve pouring, middle way and middle way flange feeding system
CN113664162A (en) * 2021-08-19 2021-11-19 中国航发沈阳黎明航空发动机有限责任公司 Large-scale thin wall foundry goods gating system more than 650mm of length
CN113664162B (en) * 2021-08-19 2022-07-29 中国航发沈阳黎明航空发动机有限责任公司 Large-scale thin wall foundry goods gating system more than 650mm of length

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