Lamina of large water turbine technology of CNC Machining of 5 axes linkage

Runner of foreword hydraulic turbine is the heart of water turbogenerator group, the production technology of its runner lamina affects the reliability of the hydraulic function that aircrew runs and aircrew directly with production quality. Lamina of hydraulic turbine runner is spare parts of very complex body of sculpture curved surface, be in large and medium-sized on aircrew workmanship, long-term since adoption " sand mold casts shovel of ─ emery wheel to grind stereo example to detect the workmanship of " , , its production efficiency is very low, blade face precision assures hard, and the labor strength that shovel of manual emery wheel grinds is great, working environment is very harsh, already cannot satisfy the requirement that the technology progresses, also cannot make sure blade range accuracy is mixed effectively production quality, cannot satisfy more generate electricity now the requirement that equipment market competes. "The " of engineering technology of CNC Machining of 5 axes linkage of lamina of large hydraulic turbine is current world generates electricity one of crucial technologies in equipment manufacturing industry, also be the most advanced hi-tech in current machining technology. It involves the three-dimensional model that assists a product to the computer, the computer emulates imitate treatment, technology of CNC of 5 axes linkage, sophisticated metallic cutting technology, three-dimensional curved surface face is measured reach fixed position technology, and semifinished product is made etc. Foreign world generates electricity first-rate equipment production company, began to threw much labor power and financial capacity to have much research and development in 80 time, because have quite great technology difficulty, also have only now individual a few companies mastered this skill, very confidential, regard the market as powerful technology measure of competition, also be to make sure hydraulic turbine is hydraulic one of effective technology measures of function. As the construction of 3 gorge project, the research of technology of CNC Machining of lamina of large hydraulic turbine and development, also make one of very crucial items in the technology as 3 gorge aircrew, through strict evaluation, foundation of science of the country that be brought into, machinist industry grows one of content in the major project that foundation funds jointly, get of two foundation aid financially, also be the State Council at the same time the 3 gorge aircrew of accreditation of commission of 3 gorge construction tackles key problem project. Lamina of large hydraulic turbine of research development " " of engineering technology of CNC Machining of 5 axes linkage, make to 3 gorge aircrew not only, and the technology that makes a trade to whole hydraulic turbine progresses, the market competition ability that enhances manufacturing industry of equipment of our country water and electricity is having important sense. My company organized certain labor power to have research and development in the light of the relevant technology in large lamina CNC Machining, successfully with Yu Mou large shaft sheds lamina of type hydraulic turbine (expensive dam continent power station) make, for home first overall use CNC Machining blade completely, the key depends on applying the computer successfully to emulate processing technique. 2.

The structural characteristic that large shaft sheds lamina of type hydraulic turbine is tall dam continent aircrew is axis of a high peak of flow aircrew drifting type, diameter of runner of its hydraulic turbine is F5.

8m. Blade is spent to twist of edge giving water from the edge that drink water big, in flange of blade the reverse side edge of the skirt outside containing, very big underdress edge is contained in blade hub side. In flange spherical area is R265 of constant R(front by the side of underdress.

2mm, rear R232.

0mm) transfers curved surface, from flange spherical area comes into, the change of curve of space of edge of curved surface R of edge giving water transfers 0. Blade flange comes outside predestined relationship diameter is F1180mm. As a result of this lamina and general axis lamina drifting type is in the structure is photogenic than having a few specialty, because of such, this caused greater difficulty to treatment craft and emulation treatment process designing. Expensive dam continent hydraulic turbine lamina is shown 1 times like the graph. Graph 1 lamina designs sketch map 3.

The structural characteristic that basis of program of CNC Machining technology wants to machine blade and numerical control of adoption movable type of 5FZG dragon door the structure of the machine tool, and particular situation researchs blade semifinished product carefully the analysis is comparative, the decision collects axis of rotation of lamina of in order to and flange end panel to serve as fixed position fiducial. Blade has many pieces of curved surface to need to machine, the serious offence sheds a face to use treatment of milling of 5 axes linkage, edge FLOWLINE(streamline) "RASTER" takes a knife. Problem of machine tool collision is prevented in machining a process definitely for solution, to blade the kind of knife axle control with rear the divisional region, cutting tool that uses different diameter, different bedding face will machine. Of area differentiate the principle is the treatment of milling cutter of curved surface face that uses big diameter as far as possible below the condition that does not collide. Because the diameter of flange of NC milling head of the machine tool is F1.

23m, of area differentiate must have the aid of emulates treatment for many times at aftermentioned imitate will decide. Distributing as a result of semifinished product surplus very inhomogenous, use thick mill and essence mill for many times. Whole treatment program must use emulation processing technique to emulate test and verify to revise on the computer will make on perfect foundation, the problem that a lot of expect are less than may appear in be being machined otherwise. The fixed position that hold clip and clamping apparatus are with line of heart of blade runner shaft coming back fiducial, in axis of craft of the solder on blade flange, end panel of thick car flange, dig two top hole in craft axis and flange end panel next. Corresponding clamping apparatus uses two centers, it is fixed tip, park flange is carried, another for axial adjustable and top, the craft axis on park flange is carried. In flange end panel mark has blade to machine the position (opposite design position - 10 ° , by hind narrate emulation treatment to decide) . Use clamping apparatus and number, the function of machine tool of have the aid of, search to arriving treatment position, certain work at 0 o'clock, the solder on the opposite that machining a face plays side, use general jack and pull rod to pull press clamp. This clamping apparatus goes easily simply, but general at the axis lamina drifting type is machined. Graph of place of treatment of motion of 2 treatment area and treatment area differentiate place of treatment of lamina of axial shedding type has blade the reverse side face, by the side of water of pass in and out, the face transfers by the side of skirt of inside and outside, flange. Wait to avert collision and cutting tool interference, through aftermentioned emulation treatment is revised for many times and test and verify, if the graph is shown 2 times, blade the reverse side undertakes each minutes machining for 3 area, its principle is do not collide in machine tool and workpiece and clamping apparatus and interfere a circumstance to fall, increase area of Ap1, As1 to machine efficiency in order to rise as far as possible. Ap1 and As1 use φ 5 axes linkage machines milling cutter of face of 200 curved surface, ap2 and As2 use φ 5 axes linkage machines milling cutter of face of 125 curved surface, ap3 and As3 use φ knife of 100 balls head 3.

5 axes linkage is machined. Edge of water of pass in and out uses φ 100 helix corn establishs milling cutter mill of side of 5 axes linkage. Graph the cutting tool that CNC Machining of 5 axes linkage machines cutting tool to machine blade with cutting tool compares 3 lamina general machining chooses cutting tool to want to consider more factors. Above all, figure of adoption geometry of milling cutter bit body should get used to curved surface treatment, should have good cutting performance and platoon bits and the function that break bits, should not suit only at protruding curved surface, and even applicable sunken curved surface, this is interfered to cutting tool is very main factor. When choosing cutting tool, want the power according to the machine tool not only, the rotate speed of milling head, blade material pledges the concerned cutting parameter that reachs cutting tool and bit makes calculation, and should emulate treatment to have its bit body, razor blade and arbor and milling head emulate and be interferinged checking computation according to aftermentioned further, in order to have integrated consideration. If cutting tool is interfered, must revise cutting tool plan and treatment method to wait, the cutting tool that decides finally namely must be in emulate and just can be informed. Mix in limits of rotate speed of machine tool power, milling head below the condition with machine tool sufficient tigidity, different diameter cutting tool is used to have consideration in emulation treatment, use big diameter cutting tool to machine efficiency in order to rise as far as possible. To expensive dam continent blade, through computation and emulation treatment test and verify, the heavy-duty cutting φ that uses 4 blade that have 60 ° tool cutting edge angle to Ap1 and As1 area milling cutter of face of 200 curved surface, ap3 and As3 use φ of tailor-made long cutting blade knife of 100 balls head, ap2 and As2 are used but the 125 curved surface of φ that big feed cutting takes bit of 8 blade circular arc face milling cutter. Edge of water of pass in and out is used but 100 helix corn establishs the φ that big feed measures milling cutter. Blade measures blade the semifinished product before including to machine is measured and treatment hind face detects. Abroad uses photoelectricity altazimuth to measure a system to undertake semifinished product measures the sampling observation with treatment hind [1] . Current, my company has not have the requirement of this respect. Measure to semifinished product, we cast technical level according to semifinished product, blade cover magic art to slant buy one set-point, by be similar to treatment method work out to check an order, the surplus that machines place certainly distributings circumstance, again according to distributinging the circumstance decides the program begins to machine from which. Treatment is over model after the face, use three-dimensional after measuring a technology to be machined to blade model the face undertakes detecting, treatment goes out model the accuracy of the face is very good, greatly requirement of standard of prep above IEC193. 4.

Emulation treatment and lamina of process designing hydraulic turbine are system of very complex sculpture curved surface, if want to use CNC Machining of 5 axes linkage successfully, its key is using the computer to emulate processing technique at development, this is attached most importance to especially to large lamina CNC Machining should, again, this also is the advanced technique method of process designing of treatment of 5 axes linkage. The issue that the automatic process designing of CNC Machining of 5 axes linkage should consider large lamina at the same time is more, want than general automatic process designing complex much, must emulate test and verify through the computer. The computer of blade emulates treatment is blade in craft of CNC Machining of much axis linkage most key and technical the strongest job, it is to assist the base that establishs technology program and work out machine program. Perfect through emulating treatment to be revised repeatedly explore reasonable treatment program and specific treatment method. Main job is to be in 2 times on the foundation of development, will realize emulation treatment with software of SDRC company CAMANDCAD/CAM. If the graph is shown 4 times,the emulation treatment of blade reachs process designing. Graph the molded lines of the lamina of three-dimensional model hydraulic turbine of the emulation treatment of 4 lamina and process designing lamina and model the requirement imitate that the face must press a design strictly, because this is to should affect as a result of performance of its fluid power the function at whole set, want to consider following projects to ask when modelling. system of blade curved surface reasonable cent becomes the combination of many pieces of curved surface, so that body of curved surface of accurate imitate lamina; The modelling method of each pieces of curved surface chooses, want can exact definition and the demand that reflect actual project; Error of curved surface formative is controlled, of curved surface cut out with extend the curved surface operation such as develop; The basis emulates the technology program when treatment, press the treatment method of each pieces of curved surface, will differentiate blade each pieces of curved surface. Lamina of hydraulic turbine of axial shedding type is the curved surface part that forms by the flange with spherical belt and curved surface of model of much Zhang Diao, cannot define these curved surface with analytic equation. How to use numeric method well and truly to come imitate lamina every pieces of curved surface, be opposite especially large lamina, this is very important. Use NURBS curved surface to approach a method every pieces of curved surface that well and truly numeric imitate gives blade to go up, also facilitate knife of CNC Machining of much axis linkage orbit computation axis sheds type lamina by what have sculpture curved surface, rear, the edge that drink water changes curved surface of circular arc radius, give water edge curved surface, flange is spherical, hub and flange are spherical, the curved surface side the skirt of flange, hub and flange and, rear transition curved surface form. Blade the reverse side is to press what fasten next giving out in columnar coordinate model value drop, write drop of a program general value to press cylinder sectional read in, change rectangular coordinates to fall, changeover becomes the REVPOST form of CAMAND, make the SPLINE curve of LOFTED along columnar and sectional line, had pressed curvilinear method to make LOFT curved surface again, such making, rear, delay develop curved surface to flange and hub. What make flange and hub by blueprint is spherical, reoccupy round cylinder makes flange rod, with hub spherical go TRIM flange axis. Wait for radius FILLET rearly by Lan Yuzheng of blueprint requirement course of action face, flange to into, of edge giving water change radius FILLET face, and TRIM hub is spherical, of flange of the lamina that delay develop by the side of the skirt that the reverse side makes flange handle the reverse side by blueprint, the edge that use skirt and lamina, rear TRIM flange is spherical, reoccupy flange is spherical TRIM rear and redundant the share that extends develop, the paper that press a plan magnifies into water edge the graph makes head curved surface, because ply is very thin,give water edge curved surface, make approximately like all the time grain face can, finished an axis to shed type lamina modelling on CAMAND so, what should notice is, formative purpose is for treatment, must consider to machine a method when modelling, if the graph is shown 5 times,the axis sheds the three-dimensional model of type lamina. Graph the knife of three-dimensional model attempt that 5 axes shed type lamina and runner computation and computation of examination of cutting tool interference and cutting are emulated above all, according to the structural characteristic of blade, plan is machined surely first (MACHININGSTRATEGY) , differentiate treatment area, what by CAMAND software the definition uses the geometrical parameter of cutting tool, include the geometrical form of bit, the geometrical appearance of bit body, cutting knife is long, arbor and appearance of link system geometry, define the parameter that concerns with the machine tool again, include feature of a few machine tools and restriction, the dimensional limits that can machine, milling head corner reachs direction to wait with the limitation that place part, finish tectonic machine tool to configure a file. Next each machine characteristic of area curved surface, the treatment with different choice walks along a knife to control methodological computation to give each area knife, combinative aftermentioned collision interferes an examination, examination area differentiates reasonable. When machining blade face, choose reasonable treatment to take knife way, matter to the on any account that processes efficiency directly. After the course is analysed, decision choice regards FLOWLINE milling as the direction of treatment along line of blade formative parameter, the curvature change of this direction lamina face is minor, be helpful for improvement of cutting technical properties. Shed type lamina to the axis, answer to wait for structural characteristic according to blade flange and skirt edge, have divisional treatment to blade. Different cutting tool and means of knife axle control are used in different area, machine efficiency with rising as far as possible. The curved surface treatment of CAMAND software has algorithm of a variety of agile knife axle control, in serious offence shedding the face can use TILT means, TANTO means is used in edge of water of blade pass in and out, in the transition of hub curved surface uses ADVANCEDPROJECTION means, CURVE/VECTORPOINTSET means treatment is used in flange place. After searching relatively reasonable area to differentiate, adjust the parameter of the means of knife axle control in machining a method further, the control of knife of pass in and out element that basically causes collision likely undertakes a knife again computation and aftermentioned emulate an examination, write melody each parameter. Undertaking blade knife notable is in computational process, to improve condition of cutting tool cutting, inspect its to machine the curvature change circumstance of the face and cutting tool length, calculate in TILT means knife of 5 axes linkage when, the LEADANGLE that gives 4 ° of a 2 ～ to control and the TILTANGLE that 5 ° of 1 ～ control. Below the condition that does not collide, to cutting tool (bit body and cutting blade) reach arbor to undertake interfering checking. Cutting tool interference undertakes with VERICUT the graph emulates an examination, if have any interference, each pace is narrated to revise the many factors that affect possibly before relapsing, the knife that till generate,collides, regard usable knife as its, in this knife wait to be calculated again with the cutting parameter that cutting tool adds on foundation of concerned treatment parameter knife, its knife use a knife for final treatment, generate treatment code for the aftertreatment. Graph the machine tool of 5 axes milling head of 7 machine tools emulates emulation flow chart of 6 lamina CNC Machining reach collision examination to be machined to large lamina, for the safety of machine tool and workpiece, undertake the machine tool is emulated in case milling head collision and cutting tool interference is special must, if the graph is shown 6 times,treatment emulates flow. Already narrated afore, collide like the discovery in emulating and interfere, must revise treatment program and treatment method. Use SDRC/CAMAND construction to give treatment lamina place to if pursue,use 〔 of NC milling head 7 〕 , concern according to milling head structure and motion, the drive shaft geometry that gives milling head to go up by the requirement definition of the Simulation function of CAMAND software (PrimaryGeometry) and driven axis geometry (SecondaryGeometry) , set the 4th axis and the concern of the 5th axis. Successive or weak condition can be used to control imitate to machine the spatial motion of the milling head in the process and arbor in Simulation, whether do examination milling head and arbor and workpiece and clamping apparatus have collision and interference (if pursue,8 show) . Notable is, the B axis of the NC milling head of 5FZG machine tool is to have restriction on machinery (± 360 ° ) , install in the configuration file of the machine tool (358 ° of ± ) relatively safe. When successive treatment, when B horn accumulates 358 ° , carry with what the Windup function of CAMAND makes the knife comes one safety is planar, invert and back down knife of one pace reentry, lest damage,cutting tool and cut already machined the surface. The motion of the milling head that can observe in the emulation process of Simulation and agrees when true treatment, to the place that collides possibly, but weak condition is mixed ahead control backward facilitate careful observation, can inquire the value of each reference axis, facilitating analysis, in order to revise technology program and treatment method. The machine tool is emulated and in front the knife that already narrated computation and beard of examination of cutting tool interference cooperate each other, revise through relapsing, ability is calculable piece reasonable and " is at ease the knife of " . Graph 8 axes shed type lamina 5 axes knife reaching emulation postposition processing and processing of machine program postposition is will before the reasonable knife that narrates computation to go out changeover becomes code of pattern of system of numerical control of specific machine tool, aftertreatment flow is shown 9 times like the graph. Aftertreatment software must be aimed at development of specific machine tool, include a machine tool to configure module (CFG) and the knife the module that orbit translates into code of specific machine tool (PPR) . Want special attention to aftertreatment of 5 axes linkage the motion between each coordinate concerns. Graph flow of 9 postposition processing uses CAMAND/UPP5 module, the command language development that defines with its goes special the aftertreatment at 5FZG machine tool implement, the machine tool that writes in the light of 5FZG machine tool in coordination again configures a file (MachineToolConfigurationFile) , will before narrate already got reasonable intermediate knife (ITP) undertakes changing generating controallable the treatment code of the machine tool. As a result of memory of part of unit of CNC of 5FZG machine tool (the limitation of PartMemory) capacity, again the each labor situation that give attention to two or morethings machines, blade machine program cent becomes many programs, like expensive dam continent blade is divided into 40 many machine program, make an appointment with 5MB, the RS232 of the RS232 that passes PC and Sinumerik880M strings together a mouth to use PCIN communication software to undertake the program conveys. 5.

Large shaft sheds the CNC Machining of type lamina to be on the fixed workbench of 5FZG, by the machine tool semifinished product of process designing set treatment direction installs good clamping apparatus, hoisting lamina searchs, measure workpiece apposition slanted at NC0 at 0 o'clock register, the program is checked and label with the examination first rear surplus, retroflexion 180 ° search again, with openly surplus inspection program is checked and mark surplus, if have surplus on the whole, outfit clip is taut, undertake checking by the requirement next, achieve treatment to ask to just can begin to undertake machining. Whether does the dimension that cutting tool and link system should affirm before treatment agree with process designing, because 5FZG machine tool still does not have length of 5 axes cutting tool,compensate a function. Edge of water of pass in and out is machined by the program first in treatment, distributing according to surplus next circumstance, machine area thick mill or mill of essence of life to each by the program. After the front is machined, in mill of the place side the water of pass in and out that relies on flange two facet offer treatment the reverse side to assist search to be being used. Fixed position is checked to use mark opening by program getting in the front. Retroflexion next 180 ° search, by similar front treatment process machines the reverse side. Each link that machines blade must careful, the lamina that treatment gives is checked via each, satisfy design requirement completely, blade range accuracy greatly requirement of standard of prep above IEC193. 6.

Lamina of runner of last word hydraulic turbine technology of CNC Machining of 5 axes linkage is current world generates electricity one of the most advanced hi-tech in equipment manufacturing industry, CNC Machining of 5 axes linkage involves lamina of large hydraulic turbine to assist a product to the computer three-dimensional model technology, computer simulation reachs emulation processing technique, machine tool of treatment of 5 axes linkage is emulated reach postposition processing, be aimed at the program of reasonable treatment technology of blade, technology of the fixed position that hold clip and clamping apparatus design and make, treatment program deserves to be mixed with reasonable cutting tool cutting parameter, and semifinished product makes the technology that waits for many link and many sided. Can say, every link and the technology that involve are new technology issue. My company passes indefatigable tough effort about technical personnel, made many foundation and development work, technology of CNC Machining of 5 axes linkage uses the blade of large hydraulic turbine that will develop successfully first at expensive dam continent treatment of lamina of power station hydraulic turbine, for domestic manufactory first whole power station and overall blade complete set uses CNC Machining. Measure data analysis from the lamina after treatment, treatment precision already achieved international advanced level, from the point of treatment process, treatment efficiency already was close to international advanced level, precede for domestic technology level. The development of this technology is successful, have very good society and economic benefits, make to 3 gorge aircrew not only, and the technology that makes a trade to whole hydraulic turbine progresses, the market competition ability that enhances manufacturing industry of equipment of our country water and electricity is having important sense. 7.

Express gratitude in the research in the project and development process, use SDRC/CAMAXCAMAND software undertakes emulation machining imitate, get gentleman of willow of agency of Beijing of company of high-quality goods machinery goes up in the technology support energetically, thanks here! CNC Milling