CN105290474A - Milling method and device for single straight-grained curved-surface blade of small-diameter closed 3-D impeller - Google Patents

Milling method and device for single straight-grained curved-surface blade of small-diameter closed 3-D impeller Download PDF

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Publication number
CN105290474A
CN105290474A CN201510416496.5A CN201510416496A CN105290474A CN 105290474 A CN105290474 A CN 105290474A CN 201510416496 A CN201510416496 A CN 201510416496A CN 105290474 A CN105290474 A CN 105290474A
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CN
China
Prior art keywords
blade
ruled
carcass
milling
impeller
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.)
Pending
Application number
CN201510416496.5A
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Chinese (zh)
Inventor
李晖
李焕军
王立博
罗忠
马辉
李朝峰
李鹤
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Northeastern University China
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Northeastern University China
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Filing date
Publication date
Application filed by Northeastern University China filed Critical Northeastern University China
Priority to CN201510416496.5A priority Critical patent/CN105290474A/en
Publication of CN105290474A publication Critical patent/CN105290474A/en
Pending legal-status Critical Current

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Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B23MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23CMILLING
    • B23C3/00Milling particular work; Special milling operations; Machines therefor
    • B23C3/16Working surfaces curved in two directions
    • B23C3/18Working surfaces curved in two directions for shaping screw-propellers, turbine blades, or impellers
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B23MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23QDETAILS, COMPONENTS, OR ACCESSORIES FOR MACHINE TOOLS, e.g. ARRANGEMENTS FOR COPYING OR CONTROLLING; MACHINE TOOLS IN GENERAL CHARACTERISED BY THE CONSTRUCTION OF PARTICULAR DETAILS OR COMPONENTS; COMBINATIONS OR ASSOCIATIONS OF METAL-WORKING MACHINES, NOT DIRECTED TO A PARTICULAR RESULT
    • B23Q3/00Devices holding, supporting, or positioning work or tools, of a kind normally removable from the machine
    • B23Q3/15Devices for holding work using magnetic or electric force acting directly on the work
    • B23Q3/154Stationary devices
    • B23Q3/1546Stationary devices using permanent magnets
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B23MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23CMILLING
    • B23C2215/00Details of workpieces
    • B23C2215/44Turbine blades
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B23MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23CMILLING
    • B23C2220/00Details of milling processes
    • B23C2220/16Chamferring
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B23MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23CMILLING
    • B23C2220/00Details of milling processes
    • B23C2220/36Production of grooves
    • B23C2220/366Turbine blade grooves
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B23MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23CMILLING
    • B23C2220/00Details of milling processes
    • B23C2220/60Roughing
    • B23C2220/605Roughing and finishing

Abstract

The invention discloses a milling method and a device for a single straight-grained curved-surface blade of a small-diameter closed 3-D impeller. The milling method comprises the following steps: (a) upper-and-lower blank 3-D solid modeling is carried out by using data of a solid model of the blade, an upper blank mold comprises a protruding to-be-milled straight-grained curved-surface blade, and a lower blank mold comprises a limiting groove in a shape matched with the shape of the to-be-milled straight-grained curved-surface blade; (b) according to the model, an upper blank body containing the protruding to-be-milled straight-grained curved-surface blade and a lower blank body containing the limiting groove are manufactured; and (3) the lower blank body is buckled up with the manufactured upper blank body backwards, so that the protruding to-be-milled straight-grained curved-surface blade of the upper blank body is clamped with the limiting groove of the lower blank body. By means of the X-direction and Y-direction positioning of the blank bodies to the blade and the Z-direction positioning of a permanent-magnet suction magnetic disk, a single blade is cut. The operation is simple; no springback amount is caused; the surface of the blade is smooth; the cutter cost is remarkably reduced; and the manufacturing time can be shortened by more than two times.

Description

The milling method of the single ruled surface blade of minor diameter enclosed 3 d impeller and device
Technical field
The present invention relates to the processing technique field of ternary vane of centrifugal air compressor, be specifically related to the milling method of the single ruled surface blade of a kind of minor diameter enclosed 3 d impeller and implement the processing unit (plant) of the method.
Background technology
Since the seventies adopts three Dimensional Design theory in turbomachinery, centrifugal compressor, with its large discharge, high efficiency advantage, is extensively subject to the favor of the industries such as aviation, machinery, chemical industry, metallurgy, environmental protection.3 d impeller is one of key components and parts of centrifugal compressor, and blade is the core of 3 d impeller, and the processing precision direct influence of blade is to the efficiency of whole unit.
Under 3 d impeller is generally all operated in high temperature, high pressure, high speed conditions, the selection of material is mostly the material such as stainless steel, high-temperature nickel-base alloy.At present, the Conventional processing methods of 3 d impeller has three kinds: (1) wheel cap, blade, wheel hub three welding methods.This method is current most popular method, advantage be simple to operate, go material less, processing charges is few, shortcoming is because blade utilizes mold hot-roll forming usually, the more difficult control of springback capacity, 5mm is greater than for vane thickness, diameter is greater than the major diameter impeller of 600mm, and hot rolling blade springback capacity is less on product quality impact, but larger to minor diameter impeller lobulus gracilis sheet Accuracy; (2) cover milled blade at wheel, then weld two welding methods of wheel hub.This processing method precision of blades is high, but complicated operation, need five-axis NC machine center, and the lobe numbers of most enclosed ternary wheel is more, between blade air inlet place leaf, gap is little, is easy to hit cutter, processing charges is high, is generally used in diameter and is greater than on the impeller of 600mm; (3) wheel cap, blade, whole wheel hub milling method.Manufacturing procedure is few, and impeller precision is high, but processed complex, and need five-axis NC machine center, processing charges is very high, is generally used in diameter and is greater than on the impeller of 800mm.
For minor diameter 3 d impeller, blade dimensions is little, complex-shaped, wall thin easily deformable (the thinnest reach 2mm ~ 3mm), and processing difficulties is:
If a () employing method (1), is easy to burning oxidation and overvoltage during blade hot-roll forming, relative springback capacity is large, larger on precision of blades impact;
B if, () employing method (2), easily elastic deformation occurs when processing blade tip, the wider elastic deformation of blade is larger, and cause blade thickness to differ, precision is low; Lobe numbers is many, and between import leaf, gap is little, and cutter cannot stretch into and process;
C if, () employing method (3), because lobe numbers is many, between import leaf, gap is little, in vane inlet and leaf, dead angle is caused adding man-hour in position, and cutter cannot stretch into and process.
Summary of the invention
In order to solve the problem of above-mentioned minor diameter 3 d impeller blade processing difficulty, the object of the present invention is to provide a kind of simple to operate, without the milling method of springback capacity, the single ruled surface blade of machining blade ganoid minor diameter enclosed 3 d impeller, the method only just need can complete required processing with Milling Motion in Three-axes NC machining center, and machining accuracy is high, cost is low, the time is fast.
For realizing above-mentioned technical purpose, the present invention adopts following technical scheme:
The milling method of the single ruled surface blade of minor diameter enclosed 3 d impeller, comprises the steps:
(a) three-dimensional modeling: utilize blade physical model data genaration ruled surface blade, with blade ruled surface for die joint carries out upper and lower tire d solid modeling, upper loose tool contains protruding ruled surface blade to be processed, and lower loose tool contains the limited impression suitable with described ruled surface blade shape to be processed;
B () prepares carcass: determine technique roughness, upper carcass and lower carcass is processed respectively according to modeler model, upper carcass contains protruding ruled surface blade to be processed, and lower carcass contains the limited impression suitable with described ruled surface blade shape to be processed;
(c) milled blade: by the upper carcass left-hand thread for preparing on lower carcass, the ruled surface blade to be processed of carcass projection and the limited impression of lower carcass are fastened, upper carcass and lower carcass is fixed aft-loaded airfoil and mills out blade.
Wherein, the diameter of described minor diameter enclosed 3 d impeller is less than 600mm; Described ruled surface blade is straightedge vane.
In described step (a), described limited impression is excised by the one-sided stretching of curved surface and generates, and three-dimension curved surface of building remains it is mold parting surface to adopt one-sided stretching to ensure, and molded line is all on die joint, is convenient to feed; Adopt and thicken excision to form the uniform thickness groove suitable with described ruled surface blade shape to be processed.
Described step (b) is with in step (c), and processing machining direction is straight burr molded line direction.
Described step (b) is with in step (c), and processing tool path pattern adopts the processing mode of high rotating speed, little cutting-in, little feeding.
Present invention also offers the device of the milling method implementing the single ruled surface blade of above-mentioned minor diameter enclosed 3 d impeller, comprise Milling Motion in Three-axes NC, described Milling Motion in Three-axes NC has workbench, and described workbench is provided with for sticking or the permanent magnetic attraction disk discharging described lower carcass.
The milling method of the single ruled surface blade of minor diameter enclosed 3 d impeller of the present invention, there is at least following beneficial effect: (1) is compared with traditional minor diameter impeller blade hot rolling method, operation is simple and reliable, machining blade is without springback capacity, smooth blade surface, machining accuracy is high, within meridional channel surface accuracy can bring up to 0.1mm; (2) cut out individual blade by carcass to the Z-direction location of the X of blade, Y-direction location and permanent magnetic attraction disk, adopt Milling Motion in Three-axes NC can complete required processing, the cost of charp tool obviously reduces, and process time can shorten more than 2 times.
Accompanying drawing explanation
The following drawings is only intended to schematically illustrate the present invention and explain, not delimit the scope of the invention.Wherein:
Fig. 1 is the middle section schematic diagram of embodiment of the present invention ruled surface blade;
Fig. 2 is the schematic perspective view of embodiment of the present invention ruled surface blade and the blanking schematic diagram of carcass blank material;
Fig. 3 is the structural representation of lower carcass;
Fig. 4 is the structural representation of upper carcass;
The assembling schematic diagram of upper carcass and lower carcass when Fig. 5 is milled blade;
Fig. 6 is the fundamental diagram of permanent magnetic attraction disk.
In figure: 1-ruled surface blade; 11-straight burr molded line; Carcass under 2-; 21-limited impression; The upper carcass of 3-; 31-ruled surface blade to be processed; 4-permanent magnetic attraction disk; The upper magnetic group of 41-; Magnetic group under 42-; 43-permanent magnet; 44-yoke.
Detailed description of the invention
Below in conjunction with drawings and Examples, set forth the present invention further.In the following detailed description, the mode only by illustrating describes some one exemplary embodiment of the present invention.Undoubtedly, those of ordinary skill in the art can recognize, when without departing from the spirit and scope of the present invention, can revise by various different mode to described embodiment.Therefore, accompanying drawing is illustrative with being described in essence, instead of for limiting the protection domain of claim.
In the present embodiment for minor diameter enclosed 3 d impeller, diameter is φ 500mm, and ruled surface vane thickness is 4mm.
The milling method of the single ruled surface blade of minor diameter enclosed 3 d impeller, comprises the steps:
(a) three-dimensional modeling:
With reference to figure 1, Fig. 2, utilize existing blade physical model data genaration ruled surface blade 1; Do two apart from minimum parallel surface S1, S2 gripping blade, the two parallel surface distances obtained are exactly the Z-direction minimum thickness H of blade, with blade ruled surface for die joint carries out upper and lower tire d solid modeling, upper loose tool contains protruding ruled surface blade to be processed, and lower loose tool contains the limited impression suitable with described ruled surface blade shape to be processed; Described limited impression is excised by the one-sided stretching of curved surface and generates, and three-dimension curved surface of building remains it is mold parting surface to adopt one-sided stretching to ensure, and molded line is all on die joint, is convenient to feed; Adopt and thicken excision to form the uniform thickness groove suitable with described ruled surface blade shape to be processed.Excise material function as adopted the thickening in 3 d modeling software SolidWorks or UG and realize above-mentioned purpose.
B () prepares carcass:
With reference to figure 3, Fig. 4, by lower tire (female tire) blank material and upper fetal hair blank respectively according to thickness (H+15) mm, (H+4) mm blanking;
The lower carcass of preparation: by lower tire (female tire) blank material clamping on Milling Motion in Three-axes NC workbench, call in procedure, adopt the flat datum level of φ 32R0.8 flat-bottomed cutter milling, and ensure that the flatness of datum level is in 0.05mm, after datum level processes, datum level is kept flat on milling machine table and clamp, start to process female tire die joint: first carry out roughing with φ 16R0.8 flat-bottomed cutter; During 1mm surplus, use φ 8 ball cutter instead and carry out semifinishing; During 0.2mm surplus, use φ 6 ball cutter instead and carry out fine finishining; Finally with φ 4R0.5 flat-bottomed cutter, back chipping chamfering is carried out to limited impression part, process the lower carcass 2 containing the limited impression 21 suitable with described ruled surface blade shape to be processed.Machining direction in semifinishing and fine finishining is all straight burr molded line 11 (as shown in Figure 1) direction, and step pitch is 0.05mm, and profile roughness reaches at more than Ra3.2;
Carcass in preparation: by upper fetal hair blank clamping on Milling Motion in Three-axes NC workbench, first carries out roughing with φ 16R0.8 flat-bottomed cutter; When also having 1mm surplus, use φ 8 ball cutter instead and carry out semifinishing; During 0.2mm surplus, use φ 6 ball cutter instead and carry out fine finishining; Finally with φ 4R0.5 flat-bottomed cutter, back chipping chamfering is carried out to protruding blade-section, process the upper carcass 3 containing protruding ruled surface blade 31 to be processed.In semifinishing and fine finishining, machining direction is straight burr molded line 11 direction, and step pitch is 0.05mm, and profile roughness reaches at more than Ra3.2;
(c) milled blade:
With reference to figure 5, permanent magnetic attraction disk 4 to be fixed on Milling Motion in Three-axes NC workbench and to clamp, lower carcass 2 is placed on permanent magnetic attraction disk 4, carcass 3 left-hand thread on band leaf good for milling on lower carcass 2, the ruled surface blade to be processed 31 of carcass 3 projection is fastened with the limited impression 21 of lower carcass 2, whether contacts well, after passed examination with the upper and lower tire of clearance gauge inspection of 0.05mm, fixed at four of upper carcass angles, permanent magnetic attraction disk leads to magnetic again; First carry out roughing with φ 16R0.8 flat-bottomed cutter; When also having 1mm surplus, use φ 8 ball cutter instead and carry out semifinishing; During 0.2mm surplus, use φ 6 ball cutter instead and carry out fine finishining; Semifinishing and fine finishining machining direction are straight burr molded line 11 direction, and step pitch is 0.05mm, until cut out blade.
Wherein, the operation principle of permanent magnetic attraction disk 4 as shown in Figure 6, by the relative motion of upper magnetic group 41 and lower magnetic group 42, realizes the addition of magnetic field intensity on work magnetic pole strength or disappears mutually, thus reaches the object that sticking fixes carcass and release carcass, simple to operation.Permanent magnetic attraction disk 4 can adopt the known common structure of the art, and magnetic group is made up of parts such as permanent magnet 43 and yokes 44, and concrete structure is no longer repeated at this.
The foregoing is only the schematic detailed description of the invention of the present invention, and be not used to limit scope of the present invention.Any those skilled in the art, equivalent variations done under the prerequisite not departing from design of the present invention and principle and amendment, all should belong to the scope of protection of the invention.

Claims (6)

1. the milling method of the single ruled surface blade of minor diameter enclosed 3 d impeller, is characterized in that, comprise the steps:
(a) three-dimensional modeling: utilize blade physical model data genaration ruled surface blade (1), with blade ruled surface for die joint carries out upper and lower tire d solid modeling, upper loose tool contains protruding ruled surface blade (31) to be processed, and lower loose tool contains the limited impression (21) suitable with described ruled surface blade shape to be processed;
B () prepares carcass: determine technique roughness, upper carcass (3) and lower carcass (2) is processed respectively according to modeler model, upper carcass (3) is containing protruding ruled surface blade (31) to be processed, and lower carcass (2) is containing the limited impression (21) suitable with described ruled surface blade shape to be processed;
(c) milled blade: by upper carcass (3) left-hand thread for preparing on lower carcass (2), the protruding ruled surface blade (31) to be processed of carcass (3) is fastened with the limited impression (21) of lower carcass (2), upper carcass (3) and the fixing aft-loaded airfoil of lower carcass (2) are milled out blade.
2. the milling method of the single ruled surface blade of minor diameter enclosed 3 d impeller as claimed in claim 1, is characterized in that: the diameter of described minor diameter enclosed 3 d impeller is less than 600mm; Described ruled surface blade (1) is straightedge vane.
3. the milling method of the single ruled surface blade of minor diameter enclosed 3 d impeller as claimed in claim 1, is characterized in that: in described step (a), and described limited impression (21) is excised by the one-sided stretching of curved surface and generates.
4. the milling method of the single ruled surface blade of minor diameter enclosed 3 d impeller as claimed in claim 1, is characterized in that: described step (b) is with in step (c), and processing machining direction is straight burr molded line direction.
5. the milling method of the single ruled surface blade of minor diameter enclosed 3 d impeller as claimed in claim 4, it is characterized in that: described step (b) is with in step (c), and processing tool path pattern is the processing mode of high rotating speed, little cutting-in, little feeding.
6. implement the device of the milling method of the single ruled surface blade of minor diameter enclosed 3 d impeller as described in any one of claim 1-5 claim, it is characterized in that: comprise Milling Motion in Three-axes NC, described Milling Motion in Three-axes NC has workbench, and described workbench is provided with for sticking or the permanent magnetic attraction disk (4) discharging described lower carcass (2).
CN201510416496.5A 2015-07-16 2015-07-16 Milling method and device for single straight-grained curved-surface blade of small-diameter closed 3-D impeller Pending CN105290474A (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106239035A (en) * 2016-08-24 2016-12-21 上海小糸车灯有限公司 A kind of bead cutter processing method of photoconduction tooth
CN111136309A (en) * 2020-01-10 2020-05-12 贵阳航发精密铸造有限公司 Method for processing triple blades into double blades

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19547952A1 (en) * 1995-12-21 1997-06-26 Goetz Metall Anlagen Clamping device for clamping workpieces with any circumferential contour
EP1206331A1 (en) * 1999-08-27 2002-05-22 StarragHeckert AG Machine tool with clamping device
CN101169645A (en) * 2007-11-28 2008-04-30 天津二十冶建设有限公司 Bending-torsional non-linear variable-diameter tube pressed mould manufacture method
CN101670462A (en) * 2009-09-29 2010-03-17 江西洪都航空工业集团有限责任公司 Wall plate processing technology for hyperboloid thin wall
CN202507074U (en) * 2011-12-29 2012-10-31 上海航天精密机械研究所 Vacuum clamp for large curved wall board
CN203636485U (en) * 2013-12-06 2014-06-11 苏州新一磁业有限公司 Positioning mechanism for machining ultrathin workpieces

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19547952A1 (en) * 1995-12-21 1997-06-26 Goetz Metall Anlagen Clamping device for clamping workpieces with any circumferential contour
EP1206331A1 (en) * 1999-08-27 2002-05-22 StarragHeckert AG Machine tool with clamping device
CN101169645A (en) * 2007-11-28 2008-04-30 天津二十冶建设有限公司 Bending-torsional non-linear variable-diameter tube pressed mould manufacture method
CN101670462A (en) * 2009-09-29 2010-03-17 江西洪都航空工业集团有限责任公司 Wall plate processing technology for hyperboloid thin wall
CN202507074U (en) * 2011-12-29 2012-10-31 上海航天精密机械研究所 Vacuum clamp for large curved wall board
CN203636485U (en) * 2013-12-06 2014-06-11 苏州新一磁业有限公司 Positioning mechanism for machining ultrathin workpieces

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106239035A (en) * 2016-08-24 2016-12-21 上海小糸车灯有限公司 A kind of bead cutter processing method of photoconduction tooth
CN111136309A (en) * 2020-01-10 2020-05-12 贵阳航发精密铸造有限公司 Method for processing triple blades into double blades

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Application publication date: 20160203