Company of author of spare parts structure bear the product treatment that make creates the job in, have a powerful person of a kind of electromagnetism, the difficult problem of deep antrum alveolus that cannot machine according to traditional method was encountered in producing a course -- its are deep of the deep, alveolus of antrum small did not encounter before, if dimension of specific spare parts pursues 1, the graph is shown 2 times. The treatment difficulty of this spare parts is very great, how to assure to machine quality to let us expend setbacks quite. 2.
Treatment difficulty is analysed by graph 1, graph 2 can see, demand of precision of deep antrum alveolus is extremely high: Deep antrum is φ 16mm, deepness achieved 40mm; The alveolus inside deep antrum is φ (0.
5 ± 0.
02) Mm, and alveolus coping contains sealing surface of protruding stage form, outside round φ 1mm, alveolus diameter 0.
5mm, deepness 5mm, deep antrum alveolus and coaxial of sealing surface of protruding stage form spend a requirement to be φ 0.
01mm, sealing surface of protruding stage form and requirement of deep antrum verticality are 0.
01mm, must install clip treatment to finish, and cannot have any deflective, cannot satisfy design requirement otherwise. Inside this spare parts of diameter of deep antrum alveolus and length than be 1:10, belong to deep Kong Jia to be versed in. Because the comparison of the deepness of aperture and diameter is big, and alveolus is in deep antrum interior again, bring about drill pipe slightness, tigidity is poor, easy generation is deflective when the job with vibration, accordingly, the precision of aperture and exterior quality are controlled hard; Additional, because hardware data is 1Cr18Ni9Ti, break bits bad, because cut,cause broach damage possibly, cannot assure the treatment quality of aperture. 3.
Treatment method exploration is aimed at this difficult problem, early days undertook is as follows exploring: (1) custom-built lengthen broach: Early or late custom-built the high-speed steel broach of lengthen, alloy steel broach more than 10, because broach itself tenacity is finite, auger cut quantity of heat to send out not easily, the space that discharge bits jams smally, easily, in machining a process broach breaks off extremely easily, even if is feed control also cannot assure very tinily. (2) use laser stiletto technology: Use laser beam drilling machine to machine this deep antrum alveolus, the result measures the circularity that discovers alveolus poorer, crucial question is to use treatment of laser beam drilling machine to must want 2 times to hold card, make sure deep antrum alveolus and coaxial of sealing surface of protruding stage form spend φ impossibly basically 0.
The requirement of 01mm. 4.
Craft analyses the deep Kong Jia inside deep antrum to be versed in, the factor that affects its to machine quality has two sides: (1) the stiffness of broach: Drill pipe slightness, tigidity is poor, easy generation is deflective, oscillatory when the job reach rupture, affect the precision of aperture and exterior quality. (2) platoon bits: Kong Xiao and deep, the passage that discharge bits is long, when cutting, getting work below the state that closes approximately, because time is longer, break bits bad, platoon bits not free, because cut,cause broach damage possibly, cannot assure the treatment quality of aperture. 5.
The characteristic that adopted step machines in the light of deep aperture reachs the requirement of pair of deep Kong Zuan, absorb before experience, combine the characteristic of deep antrum alveolus, took following step: (1) design getting cuts cutting tool to hold calorie of unit, increase the tigidity of broach. Auger cut cutting tool to install calorie of device to use structure of wrap up type, the bare share that reduces broach (see a picture 3) , in order to increase broach stiffness and strength. Install cutting fluid flow path, the action of fluid of constant pressure cutting makes have the aid of cut bits compulsive eduction, achieve a bits and cooling goal. (2) improve auger cut cutting tool. To make sure the exterior surface roughness of deep antrum alveolus asks, after needing twist drill rough machining, have precision work with reamer. To increase the loss of the reamer tenacity, reamer in preventing to machine, use tine to figure the way of halve, undertake improvement to reamer, reduced feed, increased platoon bits and look bits space, have tenacity good, medicinal powder the good point with had been heated up as good as platoon bits. (3) implementation hand moves feed getting to cut, reduce the possibility that broach breaks off effectively. The design has auger set, can realize a hand to move feed getting to cut. Although treatment facilities is point-device, also be the feed of mechanical, cannot feedback cutting strength, and armrest labour feed, can control appropriate feed, once feel cutting force passes to perhaps have greatly,get the evidence that slant, broach of the go back on the horse. Auger set cooperate clearance to control with tool noumenon in 0.
005mm less than, deeper to deepness alveolus is machined particularly effective. This kind of method can machine φ on lathe 0.
2mm alveolus. 6.
Technique machines technique to be: ① center gets cent of feed of fixed position, axial 6 times to finish, 2 times feed armrest moves feed finally. ② goes through 3 empty feed burr, make sure the exterior surface roughness of alveolus asks. 7.
Measurement technique is in graph 2 in, central alveolus diameter (0.
5 ± 0.
02) 1mm of φ of the circle outside Mm and sealing surface of form of stage of alveolus coping protruding, cannot measure directly on treatment facilities. The measurement technique that the company uses is after getting off the spare parts, with the small-sized tool that carries scale microscope is measured and video measuring instrument measures the way that ties. The first spare parts of treatment is measured with the small-sized tool microscope that carries scale first, this microscope can magnify 30 times, through adjusting graduation mark, measure dimension φ (0.
5 ± 0.
02) Mm and φ 1mm, record actual measurement cost. Next purify of deep antrum of this spare parts, be about to round φ 1mm is bulgy and outer outside sealing surface of protruding stage form, inside deep antrum of and rather than, video measuring instrument measures reoccupy, multiple of enlarge of video measuring instrument is in 30 ～ inside 200 times limits adjustable, also use 30 times measure, record actual measurement cost, bother measure an outcome, measured value satisfies tolerancepublic errand to ask to undertake batch is machined. Batch spare parts uses microscope of 30 times small-sized tool 100% measure. 8.
Epilogue adopts afore-mentioned measure and technique, solved treatment of deep antrum deep aperture to cannot assure to machine the difficult problem of quality, made sure alveolus precision and public errand ask effectively. Via examining, each index all satisfies design requirement. Unit: Technology of pneumatic of Henan spaceflight hydraulic pressure is finite author: Li Yongjian Zhang Yaoxin CNC Milling