Be based on the research of process designing of numerical control of engine whole impeller of UG

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Integral impeller serves as the crucial part of engine, very big to the function influence of engine, its treatment becomes a crucial link that improves engine performance. But the complexity as a result of integral impeller structure, technology of its CNC Machining is the difficulty of production industry all the time. The CAD/CAM software with the model -- UG, the work out goes out deep narrow groovy path, big twist horn, change the 5 coordinate machine program of the rotor of the compressor of miniature turbine engine of a round horn, be in MIKRON HSM400U undertakes experimental test and verify on machine tool of 5 coordinate numerical control, prove the feasibility of plan of CNC Machining of this whole impeller and program. Should add workpiece to had been used in miniature engine to have test-drive test. Impeller of 1 introductive whole serves as turbine (Turbine) mechanical crucial part, use at the domain such as aviation, spaceflight widely, its quality affects performance of its air motive force and mechanical efficiency directly. Because its processing technique is one of turbine production industry main task all the time. At present the foreign 5 coordinate that apply integral impeller commonly machine special software [1] , basically have the MAX-5 of American NREC company, MAX-AB impeller machines special software, the integral impeller that place of machine tool of Swiss Starrag numerical control takes machines module, still the appropriative impeller such as Hypermill machines software. In addition, a few current software if: UG, CATIA, PRO/E also can use at integral impeller treatment. Current, home has a few only a few enterprises (be like: The school such as northwest industry university and aerospace department unite some of engine major factory, professional place) can machine integral impeller, and craft level is apart from international advanced level still has very big difference. On the whole the research of domain of treatment of our country impeller and application are the same as developed country photograph to have very big difference than returning, the soft, hardware of a lot of enterprises relies on an entrance, the software aborning of own copyright did not see promotion application, in narrow more high-powered than waiting impeller makes hub of groovy path, truckle technical respect have not pass a barrier, because this studies the processing technique of high-powered impeller is imperative. The treatment of impeller of milling of whole of graph of CAD/CAM construction of system of 2 whole impeller is to show semifinished product uses forge casting die, next the basic appearance that turning makes impeller swing tower, make on center of 5 axes CNC Machining hub and lamina are machined last time in a semifinished product finish, it can satisfy requirement of strength of compressor impeller product, curved surface error is small, quality goes when dynamic balancing less, because this is better treatment method. The maturity of technology of 5 axes CNC Machining makes needed handcrafted part this kind before, can make through integral treatment come out. The plan of CAD/CAM construction of system that adopts CNC Machining method to machine integral impeller [if 2] pursues show 1 times. The structural characteristic of rotor of 3 miniature compressor and impeller of most whole of treatment difficulty home are a basis foreign impeller shrinks than what be modelled on, and the impeller that the article studies is northing the sources of energy and dynamical engineering the compressor rotor on the miniature aviation engine that the courtyard develops independently. Compressor rotor exports a diameter to be 81mm, have blade of 8 one class, lamina of 8 2 class, export blade height 3mm, impeller imports a diameter 44.

3mm, entrance lamina height 17.

15mm, blade ply is the thinnest place 0.

4mm, the smallest span is between photograph adjacent lamina 3.

1mm, if pursue 2. Achieved international to make pneumatic sex is designed advanced level, compressor rotor was used twist horn greatly, root ministry becomes round the structure such as horn, raised very tall requirement to treatment. Rotor machines difficulty to be as follows: 1, the integral impeller of coequal diameter 81mm on international has 12 lamina or 14 blade normally, and this rotor has 16 blade, and its 2 class lamina is longer also, these make machine groove to farther narrow, treatment difficulty increases further. 2, it is in cutting tool diameter 2.

Below 5mm circumstance, tigidity is poor, break easily, controlling cutting deepness also is crucial. 3, this impeller curved surface is free curved surface, flow path twist of narrow, lamina is serious, and have hind the trend that admire, add man-hour to generate interference extremely easily, treatment difficulty is tall. Interfere to avoid sometimes, some curved surface want section treatment, because this assures treatment,exterior consistency also has certain difficulty. 4, change of radius of curvature of leading edge round horn is very big, change of angle of the machine tool in machining a process is bigger, it is more difficult that and implementation surrounds blade is machined; 5, the need as a result of impeller intensity, still use between hub and lamina become round horn. Because groovy road is narrow, blade is tall, become round horny treatment also is a difficulty. Anyhow, of this impeller narrow groovy path, big twist horn, become round horn brought very great difficulty to treatment, home has not seen the integral vane wheel that treatment gives this kind of tall difficulty. The treatment of whole of impeller of treatment technology program of 4 compressor rotor uses hub and lamina to be on a semifinished product undertake form cutting, and the technique that after using blade to machine figuration, solders to go up in hub. Its machine technology program to be as follows [3-4] : 1, to increase the strength of integral impeller, semifinished product uses forge casting die commonly, undertake the turning of datum plane is machined next, treatment gives the basic appearance of impeller swing tower. The semifinished product of compressor rotor is shown 3 times like the graph. 2, the positional appropriate that the treatment opening slot of passageway of impeller air current opens groove to machine groove chooses the intermediate place in air current passageway, use parallel of marvellous milling cutter of handle of flat bottom awl to take a knife at air current passageway, make sure bottom land and hub surface leave the mental allowance with have certain, if pursue,4 are shown. Make the same score marvellous milling cutter of bottom awl handle to be hard alloy cutting tool among them, its norms is: Flat bottom divides a diameter to be: 3mm, half cone angle is 2 ° , diameter of cutting tool petiole is: 6mm, length of the part that carry drill is: 20mm. The main shaft rotate speed that this pace chooses is: 10000r/min, feed speed is: 800mm/min. Speed of rotate speed of main shaft of common on the Control Panel of numerical control machine tool stock, feed writes melody (fold) switch, the circumstance can be machined actually to undertake adjustment to speed of main shaft rotate speed, feed in the basis in machining a process. 3, the treatment of chamfer of rough machining enlarge of the enlarge chamfer treatment of passageway of impeller air current and lamina uses marvellous milling cutter of globose awl handle, begin from position opening slot, from the center outward predestined relationship is gone to chamfer of enlarge of both sides lamina, enlarge chamfer treatment should make sure blade profile leaves the finish machining surplus with have certain. Normally the circumstance falls, enlarge chamfer treatment and surface of boss of mill of essence of life are finished in treatment. Because this impeller chamfer narrow, lamina is screwy and tall, serious, and need of UGCNC Machining process designing decides cutting area according to drive face, because this enlarge chamfer machines need,divide a part to machine. The first part: Choice drive face is hub face, undertake enlarge chamfer. Cannot machine hub surface right now, still require treatment of further spread chamfer; The 2nd part: Further spread chamfer reachs blade rough machining. Choose what drive face is blade surface to slant buy side, in blade rough machining while, further spread chamfer. Among them marvellous milling cutter of globose awl handle is hard alloy cutting tool, its norms is: Ball head divides a diameter to be: 3mm, half cone angle is 2 ° , diameter of cutting tool petiole is: 6mm, length of the part that carry drill is: 20mm. The main shaft rotate speed that this pace chooses is: 20000r/min, feed speed is: 3000mm/min. 4, the precision work that the finish machining of blade, hub has below even surplus, made sure good appearance machines quality, use precision work of ball head milling cutter, because the smallest span is between photograph adjacent lamina 3.

1mm, and blade most in for 17.

15mm, considering interference, the diameter that cutting tool of rotor finish machining uses Swiss Fraisa firm 2.

The ball head marvellous milling cutter of 5, cutting tool avoids room is 20mm. Machine the main shaft rotate speed when to be: 260000r/min, feed speed is: 5000mm/min. 5, become round horny precision work is big, little of blade left to become round horn, round horn radius is to end predestined relationship from blade leading edge 1.

25mm arrives 2.

2mm arrives 1.

25mm linear changes. Among them the largest round part happens in stand by end to be in along 22 ％ . Invariable circle horn is on the right side of blade 1.

25mm. Become round horn can walk along knife treatment to finish through, at this moment the radius of part of head of cutting tool ball comes to become round greatly the smallest radius of horn. Speed of rotate speed of the cutting tool of the choice, main shaft, feed, with the finish machining of blade, hub. Above program should pass graduation, rotate, the hub that machines complete ministry or lamina execute next order again, make sure stress is released equably, reduce treatment to be out of shape error. The numerical control to program of 5 compressor rotor 5.

When the flow chart of rotor of compressor of the 1 treatment that use UG undertakes process designing of rotor numerical control with UG, it is in order to be like the flow chart that the graph shows 5 times normally guide, the knife that in order to establishs each operation orbit, the whole process of perforative treatment [2] . 5.

To program of 2 numerical control 5.

2.

1 establish father node group 1, fall in cutting tool node, join all cutting tool that treatment uses, set parameter of its cutting tool; 2, fall in geometrical node, department of coordinate of treatment of choice semifinished product, setting, choice avoids let geometry be rotor substance; 3, fall in methodological node, rate of the main shaft rotate speed when setting thick, half essence, precision work, feed and knife the indication color of orbit. 5.

2.

2 impeller enrage those who shed a passageway to open groove to machine curved surface of draw-out flow path, if line of parameter of U, V pursues 6 (A) be shown. Because the treatment of impeller passageway needs way of edge air current, arrange line of parameter of the U of flow path, V afresh so, make U parameter or direction of air current of edge of V parameter line. Because of the characteristic of curved surface of this flow path, after parameter of readjust U, V, cent of flow path face became 3 curved surface. If the V parameter line after be being arranged afresh pursues 6 (B) be shown, be direction of edge air current. 1, curved surface of flow path front (1 in the 6(b) that be like a graph) treatment uses mill of outline of alterable axis curved surface (Variable Contour) , treatment deepness is deeper, interference is more serious, it is not certain to use means of axle control of a kind of knife appropriate, because this is divided into means of axle control of two kinds of knives,undertake. One kind is: Normal To Drive (use at on half treatment) , one kind is: Toward Point (use at issueing half treatment) . On treatment half, the parameter of the program installs as follows: 1) drive method (Drive Method) use Surface Area; 2) drive geometry chooses curved surface of flow path front, pursue namely 1 in 6(b) ; 3) build avoid let geometry, serve as with spare parts whole avoid let geometry, if interference retreats a knife automatically, choose when general rough machining retreat a knife automatically to avert interference. 4) rough machining, row spacing chooses Tolerance=0.

1mm; 5) means of knife axle control is: Normal To Drive; 6) the Start Step of the Surface% in cutting area, End Step installs for: 50, express to machining intermediate position cutting one knife; 7) install Non-Cutting, be not cutting motion namely, choose knife of advance and retreat of edge cutter shaft; 8) below Cutting, set Stock surplus: 7mm; Install Multiple Passes (multilayer treatment) , every are cut deeply 0.

5mm. Below treatment half, the parameter of the program installs as follows: 1) means of knife axle control is: Toward Point; 2) below Cutting, set Stock surplus: 0.

2mm; Install Multiple Passes (multilayer treatment) , every are cut deeply 0.

5mm. 3) other parameter setting, process on half order together. Because key of mill of outline of alterable axis curved surface is means of choice knife axle control, because this follow-up treatment shows cutter shaft only,control fashion. 2, curved surface of flow path Zun Duan (2 in the 6(b) that be like a graph) what treatment uses is mill of outline of alterable axis curved surface, machine this curved surface, means of knife axle control is Normal To Drive a kind (use at on half part to machine) , one kind is Relative To Drive (use at issueing half part to machine) . (3) flow path is right upright curved surface (3 in the 6(b) that be like a graph) machine curvature of this curved surface change is very gently, each bits of law on curved surface to be close to 0º with included angle of blade curved surface, because this machines place of this curved surface,the cutter shaft of the choice controls means to be Normal To Drive. If the graph is shown 7 times,build treatment knife course. 5.

2.

The chamfer of enlarge of enlarge chamfer treatment of passageway of 3 impeller air current machines knife course similar treatment opening slot, the Start Step setting that is the Surface% in cutting area only is: 0, End Step: 100, state cutting makes a flow path range, if the graph is shown 8 times,build knife course. 5.

2.

Flow path has been machined after the chamfer of rough machining enlarge of chamfer of 4 further spread and lamina is machined major surplus, to assure to there is even mental allowance before finish machining, raise final surface to machine quality, this pace is to continue enlarge chamfer and blade rough machining. Machine what drive face chooses blade to slant buy side, if the graph is shown 9 times, if the emulation result after rough machining of flow path, lamina pursues 10 are shown. 5.

2.

5 rotor the finish machining of lamina of one class, 2 class (attraction face, pressure area, before round horn) transfer to change to pressure area curvature from attraction face acuteness, accordingly, take attraction face, pressure side, before round horn is machined apart. Lamina of one class, 2 class range is similar, machining parameter is similar, the general parameter that blade finish machining is below is installed. 1) drive geometry choice should machine curved surface; 2) means of knife axle control is: Relative To Drive, the key is choice parameter Tilt, Lead; 3) install Non-Cutting, choose direction of cutter shaft of feed of edge cutting direction, edge to retreat a knife; 4) setting of finish machining Stock is: 0mm; Generated treatment knife course, if pursue 11. 5.

2.

Ministry of 6 lamina root becomes round because horny finish machining becomes round curvature change of horn is acuteness, because this uses Relative(Normal) To Drive to control cutter shaft direction to be interfered easily with other lamina, because this is big, small,the means of knife axle control of blade is: Toward Line, control cutter shaft route with only sometimes, incontrollable still treatment a piece of complete curved surface, the likelihood should choose a few control line. Big lamina is left become round if course of horny treatment knife pursues 12, small lamina is left become round course of horny treatment knife, if pursue 13. Result of 6 conclusion test proves the plan of CNC Machining of impeller of this miniature whole is feasible, use UG to be able to realize the CNC Machining process designing of impeller of complex miniature whole, treatment result is favorable. This adds workpiece to had used the test-drive test of Yu Wei engine. CNC Milling CNC Machining