Method for shaping complex-profile inter-blade ducts of monoimpeller of gas-turbine engine and tool for performing the same

FIELD: working parts by cutting, namely processes and equipment for making aircraft engines.

SUBSTANCE: in order to enlarge manufacturing possibilities and to improve efficiency, cutting of back, trough and bottom of inter-blade duct is realized simultaneously for one technological procedure by means of one annular cutting tool and blade edges are further worked before finishing them. Rotation axes of tool and mono-impeller are arranged in such a way that they cross by predetermined angle depending upon curvature of worked surfaces while providing rectilinear motion of cutting tool along three axes of three-dimensional coordinate system and rotation of cutting tool around said three axes. Tool includes cutting end members arranged along annular perimeter of body. Tool is in the form of T-shaped cutting members arranged uniformly along perimeter of annular body with width equal to that of inter-blade duct in root cross section. T-shaped cutting members have end, outer and inner lateral cutting edges. Diameter of circle described around outer lateral cutting edges of tool is equal to that of circle inscribed to trough profile of mean cross section of blade by three points. Non-equal legs of outer and inner lateral cutting edges of trough profile correspond to twisting value of blades along height and spacing from rotation axis of cutting tool till projections of nearest points of inlet and outlet edges of boundary cross section of inter-blade duct on rotation plane of tool. Length of T-shaped cutting member is determined by value exceeding depth of inter-blade duct.

EFFECT: enlarged manufacturing possibilities, improved efficiency.

2 cl, 6 dwg

 

The invention relates to the field of aircraft engine industry related manufacturing a blisk GTE, mainly with geometrically-complex blades with twisted shape of the pen.

A method of processing bevel gears with circular shape of the teeth, which gear-head annular shape with end cutting elements handle side surfaces of the teeth and the spaces between them [patent SU # 1526935, 23 F 9/00, BI No. 45, 1989].

The disadvantage is that this method cannot handle interscapular channels complex profile in the manufacture of blisk GTE.

A known method for manufacturing a blisk GTD-based shaping interscapular channels blisk [production technology of aircraft gas turbine engines: Textbook. Manual for schools / Useview, Agibalov, WMV, Lahoratory. M: engineering, 2003, s-363] and includes pre-cutting of grooves in the workpiece in the form of a disk with abrasive jet cutting, finishing milling interscapular channels end mills and finishing blades polishing.

The disadvantage of this method of processing is its complexity due to the implementation of processing for multiple operations with low performance jet abrasive cutting (pre-slotting PA is s) and also the low performance end mills (finishing interscapular channels) and low resistance.

A method of processing bevel gears with circular shape of the teeth [patent SU # 1526935, B 23 F 9/00, BI No. 45, 1989], implemented in the tool for processing the lateral surfaces of the teeth and depressions between them, which are ring-shaped with end cutting elements located on the perimeter of the hull.

The disadvantage of this tool is that it can't handle complex surface profile, such as in the manufacture of blisk GTE.

Solved problem of the invention is the expansion of technological possibilities of formation process of geometrically-complex interscapular channels blisk GTE and processing capacity.

This object is achieved in that in the method of forming geometrically-complex interscapular channels blisk GTE, including the cutting of grooves, the final machining of the back, the trough and the bottom of the interscapular channels, finishing blades of the blisk, are simultaneous cutting and nishing in one process set one ring cutting tool with the subsequent completion of the edges of the blades before finishing, and the axis of rotation of the tool and monocausal processing have crossed relative to each other at a given angle, determined by the curvature of the machined surfaces, the tool reported rectilinear motion in three dimensions along the three spatial axes of the coordinate system and the rotation of the tool at a given angle carry around these three axes of a spatial coordinate system.

In the tool for implementing the method, are ring-shaped, containing end cutting elements located on the perimeter of the circular shape of the hull, mechanical cutting elements made in the form of a T-shaped cutting elements, evenly spaced around the perimeter of the ring body with a width equal to the width of interscapular channel in the root section, with T-shaped cutting elements made with the face, the outer and inner side cutting edges, the diameter of the circle circumscribed around the outside of the side cutting edges of the tool equal to the diameter of a circle inscribed in the profile trough the middle section of the blade by three points and with unequal shoulders external and the inner lateral cutting edges defined by the magnitude of the spin vane height and distance from the axis of rotation of the tool until the projections nearest points, respectively, the input and output edges of an end section interscapular channel in the plane of rotation of the tool, the length of the T-shaped cutting cell battery (included) is determined by the value exceeding the depth of interscapular channel.

To clarify the essence of the invention consider: figure 1 - shows the relative location of the annular cutting tool 1 and the workpiece blisk in the initial position, and the coordinate system X, Y, Z, associated with the tool.

Figure 2 shows the blade blisk GTE and cross section a-a blade in the end portion, In the mid-section and the cross section of the blade root part.

Monowheel (figure 1) is a disk in the form of a truncated cone 2, where the blades 3 with spin, i.e. with variable curvature of the trough 4 and the back 5 (figure 2), which increases from the end portion of the blade root. Processed monowheel fixed in the device, which is carried out by rotating blisk 360°/n degrees after processing each interscapular channel, where n is the number of blades of the blisk.

Figure 3 shows the cross section of the annular tool with mechanical cutting elements T-shaped, located on the perimeter of the tool. The Z-axis of the three-dimensional coordinate system coincides with the axis of rotation of the tool. The tool during processing is set so that the Y-axis is perpendicular to the chord of the processed profile blades drawn through the centers of the corner radii of the input and output edges of the blade. Cutting cha is thew are end 6, and 7 internal and external 8 side cutting edges. Processing trough blades perform external riusa edge 8 of the tool, the processing of the back of the shoulder - internal cutting edge 7, and the processing of bottom interscapular channel - end cutting edge 6.

Width At end cutting edge 6 of the tool in figure 3 is defined in the root section interscapular channel. It is equal to the distance between the link trough and parallel tangent to the interscapular back channel (figure 4).

The diametrical dimensions of the tool are determined by the profile of the mid-section of the blade height, parallel to the X-Y plane of the tool. The diameter of the circle D, described around the outside of the side cutting edges of the tool equal to the diameter of a circle inscribed in the profile trough the middle section of the blade by three points.

The length of the T-shaped cutting element And figure 3 is defined structurally from the condition of the processing tool bottom interscapular channel and must be greater than the depth of the interscapular channel to a value not greater than 5 mm to ensure the rigidity of the cutting element.

The shoulders 9, 10 external and internal lateral cutting edges are defined by radii R1and R2respectively (figure 3). Their value depends on the degree of twist of the spade in height and is of the following conditions:

R1ubiraetsa thus, so it does not exceed the distance from the axis of rotation of the tool during the processing trough root section to the projection of the nearest point of the input edge of an end section on the X-y plane when the processing trough the root portion of interscapular channel external cylindrical surface of the end part of the tool 11 will not affect the input edge of the end portion interscapular channel.

R2is chosen so that it was not less than the distance from the axis of rotation of the tool during the processing back to the root section to the projection of the nearest point of a trailing edge of an end section on the X-y plane when the treatment backless root portion of interscapular channel inner cylindrical surface of the end part of the tool 12 will not affect the output of the edge end portion interscapular channel.

The processing is as follows: ring tool 1 in the initial position set relative to the procurement of the blisk in such a way that their axes of rotation intersect at a right angle, and the vertical axis machined blades Z′ and the axis of rotation of the blisk Z parallel. The tool is put into rotation and inform translational motion along the Z-axis in the direction of parts through removal of metal, and X, Y for forming the desired profile of the trough, back and bottom megapatch the second channel.

Processing produce a string method. First carry out the incision to a depth of 1-2 mm and process the profile of the trough 4 interscapular channel external cutting edges 9 of the T-shaped cutting elements, moving the tool along the trough. Then move the tool in the X-Y plane, while cutting in the direction of the backrest 5 interscapular channel and produce cutting to a depth of 1-2 mm Further process the backrest 5 interscapular channel inner cutting edges 10 of the T-shaped cutting elements, moving along her instrument. Then move the tool to the trough and the cycle is repeated again (figure 5).

For certain sections of the treated surface interscapular channel are separate methods of processing tool. This is conventionally divided interscapular channel into two areas: from the end portion of the middle section and the middle section of the root part.

When they process trough interscapular channel from the end portion to the mid-section of the tool is moved along the profile of the trough line (figure 5), since the outer diameter of the tool is less than the diameter of a circle inscribed in the profile of the trough. Processing trough from the middle section to the root portion is performed by moving the tool along the profile of the trough. However, the outer diameter of the tool is that larger than the diameter of a circle, inscribed in the profile of the trough, so decreasing radius of curvature original instrumental surface by rotation of the axis of rotation of the tool Z-axis Y at an angle of inclination of the bottom of the interscapular channel to the axis of rotation of the blisk (projection of a circle on the X-Y plane is an ellipse, and in this case, processing of the profile is used the area of an ellipse with a smaller radius of curvature).

When they process the interscapular back channel from the end portion to the middle section, the tool is moved along the profile of the back. However, the internal tool diameter smaller than the diameter of the circle circumscribed around the profile of the back, thus increasing the radius of curvature of the original instrumental surface is carried out by rotation of the axis of rotation of the tool Z-axis X at an angle of inclination of the bottom of the interscapular channel to the axis of rotation of the blisk (in this case, the area of an ellipse with a smaller radius). When processing of the back from the middle section to the root portion of the inner diameter of the tool is larger than the diameter of the circle circumscribed around the back of the blade, so the tool is moved along the profile of the backrest.

The processing profile of the blades on the line, one needs to ensure that every moment of processing the Y-axis of the tool was perpendi alarna the chord of the blade, drawn through the centers of the corner radii of the inlet and the inlet edges of the blades. For processing the Y-axis is rotated around the Z axis, providing the above-mentioned condition (6).

When processing the bottom interscapular channel you want to rotate the Z-axis of rotation of the tool to enable the processing of bottom interscapular channel end cutting edge of the tool.

After processing one interscapular channel shall rotating blisk 360°/n degrees, where n is the number of blades of the blisk, and proceed to process the next interscapular channel.

After processing all interscapular channels blisk before finishing produce a revision of input and output edges of the blades, end mills.

In comparison with the known analogs of the invention can increase the efficiency of shaping interscapular channels blisk GTE due to the expansion of technological capabilities and improve the performance of processing time reduction for the simultaneous cutting and machining in one setup, as well as through the use of high-performance cutting tools.

1. Method of forming geometrically-complex interscapular channels blisk of a gas turbine engine (GTE)including cutting of grooves, the final machining of the back, bark is a and the bottom interscapular channels and finishing blades of the blisk, characterized in that the cutting and finishing processing of the back, the trough and the bottom of the interscapular channel are simultaneously in one process set one ring cutting tool with the subsequent completion of the edges of the blades before finishing, and the axis of rotation of the tool and blisk when processing have crossed relative to each other at a given angle determined by the curvature of the machined surfaces, the tool reported rectilinear motion in three dimensions along the three spatial axes of the coordinate system and the rotation of the tool at a given angle carry around the three axes of the spatial coordinate system.

2. Tool for cutting and finishing of geometrically-complex interscapular channels blisk of a gas turbine engine (GTE), containing the mechanical cutting elements located on the perimeter of the ring-shaped body, characterized in that it is made in the form of a T-shaped cutting elements, evenly spaced around the perimeter of the ring body with a width equal to the width of interscapular channel in the root section, with T-shaped cutting elements made with mechanical, external and internal side cutting edges, the diameter of the circle circumscribed around the outside of the side cutting edges of tools is ment, equal to the diameter of a circle inscribed in the profile trough the middle section of the blade by three points and with unequal shoulders of the outer and inner lateral cutting edges defined by the magnitude of the spin vane height and distance from the axis of rotation of the cutting tool to the projections nearest points, respectively, the input and output edges of an end section interscapular channel in the plane of rotation of the tool, the length of the T-shaped cutting element is defined by a value exceeding a depth of interscapular channel.



 

Same patents:

Cutter // 2191095
The invention relates to the field of metal industry, machining the working surface of the rail head, including the roll surface and curved surface mating with the roll surface and the side face of the rail head

The invention relates to mechanical engineering and can be used in the treatment of parts made of different materials, bounded by curved surfaces handicaps, such as combustion engines, prosthetic and orthopedic products, etc

FIELD: metal machining.

SUBSTANCE: method comprises setting the device for securing the blade in the machine-tool, securing the blade to the device, measuring deviation of its actual position from the position of the reference blade, and orienting the device together with the blade until the axis of the blade and axis of the machine-tool is aligned. The device has lid and plungers. The lid is mounted inside the housing and closed with respect to it. The lid receives plungers and clamping members that are unmovable. The plungers pass through the housing, are spring-loaded with respect to it, and can axially move.

EFFECT: enhanced precision of machining and simplified structure.

2 cl, 3 dwg

FIELD: metal cutting processes and equipment, milling by means of end milling cutter blades of one-piece impellers of gas turbine engines in number program control machine tools.

SUBSTANCE: method comprises steps of rough working for cutting inter-blade grooves of the same width in radial direction and finishing for milling blade along height. Both types of working are performed at one mounting operation. In order to improve accuracy, working is performed along lines and depth of each line is set more than thickness of deformed layer of blank after previous working. For each line deformation value of worked surface of impeller is set more than deformation value of worked surface after working i-line.

EFFECT: enhanced accuracy of working.

4 cl, 5 dwg

The invention relates to the manufacture of fitted surfaces of the rotors with integral design set of blades

The invention relates to mechanical engineering and can be used in the machining of products of complex spatial forms, such as turbine blades

The invention relates to the field of metal and are designed in particular for milling of turbine blades, the blades of the power plant, and also drives the compressor

The invention relates to metal cutting and can be used for the surface treatment of workpieces by milling on CNC machines

FIELD: metal cutting processes and equipment, milling by means of end milling cutter blades of one-piece impellers of gas turbine engines in number program control machine tools.

SUBSTANCE: method comprises steps of rough working for cutting inter-blade grooves of the same width in radial direction and finishing for milling blade along height. Both types of working are performed at one mounting operation. In order to improve accuracy, working is performed along lines and depth of each line is set more than thickness of deformed layer of blank after previous working. For each line deformation value of worked surface of impeller is set more than deformation value of worked surface after working i-line.

EFFECT: enhanced accuracy of working.

4 cl, 5 dwg

FIELD: metal machining.

SUBSTANCE: method comprises setting the device for securing the blade in the machine-tool, securing the blade to the device, measuring deviation of its actual position from the position of the reference blade, and orienting the device together with the blade until the axis of the blade and axis of the machine-tool is aligned. The device has lid and plungers. The lid is mounted inside the housing and closed with respect to it. The lid receives plungers and clamping members that are unmovable. The plungers pass through the housing, are spring-loaded with respect to it, and can axially move.

EFFECT: enhanced precision of machining and simplified structure.

2 cl, 3 dwg

FIELD: working parts by cutting, namely processes and equipment for making aircraft engines.

SUBSTANCE: in order to enlarge manufacturing possibilities and to improve efficiency, cutting of back, trough and bottom of inter-blade duct is realized simultaneously for one technological procedure by means of one annular cutting tool and blade edges are further worked before finishing them. Rotation axes of tool and mono-impeller are arranged in such a way that they cross by predetermined angle depending upon curvature of worked surfaces while providing rectilinear motion of cutting tool along three axes of three-dimensional coordinate system and rotation of cutting tool around said three axes. Tool includes cutting end members arranged along annular perimeter of body. Tool is in the form of T-shaped cutting members arranged uniformly along perimeter of annular body with width equal to that of inter-blade duct in root cross section. T-shaped cutting members have end, outer and inner lateral cutting edges. Diameter of circle described around outer lateral cutting edges of tool is equal to that of circle inscribed to trough profile of mean cross section of blade by three points. Non-equal legs of outer and inner lateral cutting edges of trough profile correspond to twisting value of blades along height and spacing from rotation axis of cutting tool till projections of nearest points of inlet and outlet edges of boundary cross section of inter-blade duct on rotation plane of tool. Length of T-shaped cutting member is determined by value exceeding depth of inter-blade duct.

EFFECT: enlarged manufacturing possibilities, improved efficiency.

2 cl, 6 dwg

FIELD: aircraft engine construction, operations for milling inter-blade passages of impellers or mono-wheels of gas turbine engines.

SUBSTANCE: method comprises steps of milling inter-blade passages; milling back and saddle of blade and recess between them. In order to lower labor consumption of manufacturing process, inter-blade passages to be milled are marked with numbers and they are milled alternatively next but one. Alloy is poured to milled passages and then adjacent inter-blade passages are milled. After such procedure alloy is removed by melting out. It is possible to pour Wood's alloy into milled inter-blade passages.

EFFECT: reduced labor consumption of manufacturing method.

2 cl, 5 dwg

FIELD: machine building.

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EFFECT: higher accuracy of milling and lower roughness of machined surface.

7 cl, 5 dwg

FIELD: metallurgy.

SUBSTANCE: method includes migration of tools by defined by splines pathes. Splines are point - to point calculated, this point are stored in CAD and CAM systems in coordinate system related to treated detail or in coordinate system of machine tool. Tool path is formed on the basis of six splines, if control points are defined in coordinate system related to treated detail, and on the basis of five splines, if control points are defined in coordinate system of machine tool, with independent spline forming for each coordinate. Facility contains programmer for tool path programming and, at least one tool motion controller by defined by spline pathes. For achieving the same technical result programmer is implemented in the form of CAD/CAM system, containing functionally related to programmer facilities for splines calculation by control points, stored in CAD/CAM system. Additionally mentioned facilities are implemented with ability of tool path forming on the basis of six splines, if control points are defined in related coordinate system of treated detail, and on the basis of five splines, if coordinate pointed are specified in coordinate system of machine tool, with independent spline forming for each coordinate. CAD/CAM system is implemented with ability of creation at least one APT-file, converted at least by one following postprocessor into at least one control file executable by control unit. Additionally control unit is provided for migration of tools control lengthwise its path on the basis of corresponding splines.

EFFECT: improvement of treated surface.

4 cl, 3 dwg

FIELD: technological processes.

SUBSTANCE: method includes definition of cut contours by contours of side walls and/or bladed channels, further removal of material by drilling from blank in places of interblade channels location, and after drilling - final milling of interblade channels location by means of material removal left in interblade channels. In process of interblade channels drilling material is removed by drill in direction of gas flow in interblade channel, and axes of openings are installed approximately parallel to direction of gas flow in interblade channel drilled in blank.

EFFECT: increased efficiency of processing.

10 cl, 7 dwg

FIELD: engineering industry.

SUBSTANCE: invention refers to engineering industry, and can be used for grinding, polishing and milling spatial polysurfaces of details, and namely propeller blades, working part of gas, steam or hydraulic turbine blades. At the device bottom there arranged is the point for installing the machining tool with the tool rotary drive, and the point for installing the machined item in the form of multilink manipulator. There provided are two mechatronic modules of rotary and translational movements - machined item movement module and cutting tool rotary drive movement module. Each module consists of a housing, splined bush, nut and outlet shaft. Stators of two synchronous electric motors are fixed on the housing, rotor of the one synchronous electric motor - on splined bush, and rotor of the other synchronous electric motor - on the nut. Outlet shaft is connected by means of a rectilinear kinematic pair made in the form of a spline connection to splined bush, and by means of a screw pair - to nut. Outlet shaft is hollow. Nut and splined bush are connected to the housing by means of turning pair made in the form of ball bearing or slide bearings. All kinematic pairs of each mechatronic module of rotary and translational movements have a common axis. There provided is at least one kinematic pair with the appropriate drive which is intended for moving the cutting tool rotary drive movement module housing relative to machined item movement module housing.

EFFECT: improving accuracy and efficiency of processing due to decrease of a number of kinematic pairs and movable links, and decrease of mass thereof.

5 cl, 6 dwg

FIELD: metallurgy.

SUBSTANCE: according to the invention, the method provides for item rotation around its axis and item machining by a tool making rotational movements and interpolated axial displacement. Preliminary, natural blade vibration frequencies are calculated for each line and angle of blade turning. Resonant behavior lines are then determined and tool rotation frequency is set for each above line based on a condition that dynamic component of generated roughness is minimised. In addition, blade rotation frequency for each line by the blade turning angle is set provided that the required speed of peripheral feed is ensured.

EFFECT: improved quality of machining.

2 tbl, 1 ex

FIELD: metallurgy.

SUBSTANCE: method relates to milling of details made of hard-to-cut materials, first of all milling of used rotor in gas turbine with set of implemented with it blades by means of milling cutter movement by at least one predetermined path. Additionally to path or to each path of milling cutter it is defined at least one corresponding to surfaces or edges by at least on side surface collision contour, which or each of which relates herewith to manufactured detail, and it is controlled position and/or orientation of milling cutter relative to collision contour or each collision contour, changing the position and/or orientation of milling cutter and/or forming message about the mistake, is milling cutter break at least one of collision contour.

EFFECT: reliability growth of treatment process.

7 cl, 2 dwg

FIELD: working parts by cutting, namely processes and equipment for making aircraft engines.

SUBSTANCE: in order to enlarge manufacturing possibilities and to improve efficiency, cutting of back, trough and bottom of inter-blade duct is realized simultaneously for one technological procedure by means of one annular cutting tool and blade edges are further worked before finishing them. Rotation axes of tool and mono-impeller are arranged in such a way that they cross by predetermined angle depending upon curvature of worked surfaces while providing rectilinear motion of cutting tool along three axes of three-dimensional coordinate system and rotation of cutting tool around said three axes. Tool includes cutting end members arranged along annular perimeter of body. Tool is in the form of T-shaped cutting members arranged uniformly along perimeter of annular body with width equal to that of inter-blade duct in root cross section. T-shaped cutting members have end, outer and inner lateral cutting edges. Diameter of circle described around outer lateral cutting edges of tool is equal to that of circle inscribed to trough profile of mean cross section of blade by three points. Non-equal legs of outer and inner lateral cutting edges of trough profile correspond to twisting value of blades along height and spacing from rotation axis of cutting tool till projections of nearest points of inlet and outlet edges of boundary cross section of inter-blade duct on rotation plane of tool. Length of T-shaped cutting member is determined by value exceeding depth of inter-blade duct.

EFFECT: enlarged manufacturing possibilities, improved efficiency.

2 cl, 6 dwg

FIELD: aircraft engine manufacture, making of gas turbine engine one-piece impellers having complex-profile blades with large twisting.

SUBSTANCE: tool is mounted with possibility of rotation around its own axis and it includes cutting edges uniformly arranged on perimeter of body of revolution at its end side. In order to improve efficiency of forming blades tool is in the form of ring mounted inside housing in such a way that its lateral surface may move on inner annular surface of housing. Said ring may be driven to rotation around its own axis by means of gear transmission. Housing embraces more than half of ring. Lateral surface of ring may be mounted in bearing assembly arranged on inner annular surface of housing and it has teeth engaged with pinion mounted in housing for forming usual or planetary gear transmission. Cutting edges of tool may be detachable ones or they may be arranged on detachable annular insert. Cutting edges of tool may be T-shaped.

EFFECT: enhanced operational effectiveness of tool.

6 cl, 3 dwg

FIELD: metal working, metal cutting tools.

SUBSTANCE: milling cutter includes body and tips of hard alloy mounted on surface of tool body for providing working of one lateral face, radius surface joined with said lateral face and part of rail head rolling surface. In order to improve efficiency of using milling cutter due to working the whole surface of rail head, milling cutter is provided in addition with tips of hard alloy mounted on surface of cutter body for successive working of the whole rolling surface of rail head, its other lateral face and radius surface joined with said other lateral face.

EFFECT: improved efficiency of working.

1 dwg

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