In deep aperture treatment, it is good that because have the effect that divide bits,deep aperture of bits of the platoon inside wrong tine is gotten, platoon bits efficiency of smooth, treatment is tall and treatment precision is more advanced characteristic, because this received wide application. But deep Kong Zuan of bits of the platoon inside common wrong tine also is existing the place of a few inadequacy, be aimed at these problems, we designed deep Kong Zuan of bits of the platoon inside a kind of new-style wrong tine, reach cutting function trial through be being used actually, prove this deep aperture drilling tool has good cutting performance and applied effect. The problem that bits deep aperture discharges to get existence inside common fault tine discharges bits deep aperture to get inside common wrong tine, according to broach diameter size, can divide for 3 tooth or 5 tooth structure, each tooth parts the tine outside be, inside tine and intermediate tine, because intermediate tine and center age the tine outside mixing is not on same cone, want tower above however a H is worth their cone (the) on axial, because this can obtain the better result that divide bits, at the same time each tooth is returned can choose different bit material according to the cutting position that differs severally. But deep aperture of bits of the platoon inside common fault tine is gotten on tooth structure and geometrical parameter to also existing a few inadequacy, main show is in: Sharp angle 2F is lesser, get a tip taller, tine arrives outside direct a lag amount between is larger, into get and give the time that get longer, cause easily get a process to break tine and collapse blade phenomenon mediumly, broach durability is inferior, bore quality is poorer also. Because sharp angle is lesser, each tooth is on broach cone edge radius is ordinal when arranging, the axial height difference between tooth is opposite bigger. Reason is being entered auger, piece get level, central tine should bear alone greater axial power and radial load, make cutting vibration bigger, centering effect is poor, blade of easy generation collapse. Intermediate tine, outside the role of point of a knife of tine is minor, pointed role is prominent, intensity is reduced, once pointed character appears,wear away, between tine build receive a quantity to be destroyed, cause collapse tine easily to reach twist get an accident. Blade slants inside horny T2 is lesser, get the hole bottom when cutting to turn over awl height inferior, centering action is abate, cause cutting vibration easily. Getting in cutting a course, the radial join forces of the action on broach should be pointed to from beginning to end two oriented piece between, in order to make sure broach is in stable cutting position. But restrict as a result of broach diameter and bit dimension, the broach that designs sometimes, its press guide to piece radial pool efforts is minor, and when wear away when bit or meeting material horniness to nod, instantaneous of radial join forces can point to opposite way, can lose so auger cut a balance and produce vibration, cause bore thereby deflective reach helix channel issue, affected bore quality. The structure that deep aperture of bits of the platoon inside new-style fault tine gets and graph of blade form characteristic discharge bits inside tine of 1 new-style fault deep Kong Zuan is aimed at bits of the platoon inside common fault tine the problem that deep Kong Zuan exists, we discharge the base that bits deep aperture gets to go up inside common fault tine, undertake corresponding improvement to broach structure and blade form, designed deep aperture of bits of the platoon inside a kind of new-style wrong tine to get (call bits of the platoon inside much more pointed tine) of deep Kong Zuan again, its head structure and blade form are shown 1 times like the graph, the main characteristic on its structure and blade form is as follows: Increased broach sharp angle, with reducing the axial height difference between each tooth further, shorten auger, piece get time, decrease to be not gotten firmly surely cut time, in order to raise the durability of broach. the needle of wear of intermediate tine blade on the right side of axes tooth form, the hole bottom that makes treatment goes out forms centering annular groove, increase inside blade bevel T2, oppose drill with making get the hole bottom when cutting to form taller centering (2) seeing a picture, double centering is cut with stability getting. Except tine and outside outside be pointed horn along a side, the others tooth undertook pouring wine cup, contain the part after the side of ° of 6 ° ~12 at the same time, eliminated pointed role, the radiator that increased tooth is accumulated, also enhanced tooth strength at the same time, blade of not easy collapse, be helpful for raising the durability of broach. Graph the appearance of 2 treatment hole bottom increased to get pointed offset E, age in the center inside a blade inside form of two broken line is ground on blade, namely inside blade by & the composition of broken line blade with different rake, reduced broach height Dh effectively so, shortened into auger, give the time that get, make thereby stability getting can be entered to cut level immediately when getting, and the center ages and intermediate tine cuts work at the same time almost, can improve the position getting power of tooth, reduce cutting vibration. And piece when getting, because go out,get time weak point, cutting cap is decreased thin, force of the cutting on each tooth disappears at the same time almost, be helpful for decreasing brace up reach rise auger cut stability. According to each tooth different cutting bear reachs cutting position, the axial power that the center ages place gets is greater, extruding, attrition is serious, cutting condition is abominable, can choose bending strength the YG with tall, good impact resistance kind bit, and outside tine and intermediate tine because cutting speed relatively central tooth depth, reason should choose red rigid the bit stuff with good, expensive wearability, wait like YT798, YW1. Add in cutter hub back end decrease brace up piece, in order to protect tooth and the appearance precision that increase treatment opening; Wear away when tooth or collapse blade is caused auger when cutting vibration, it can rise to decrease brace up, disappear brace up action. Reduce oriented piece with the height between cutter hub, rise oriented piece bending strength. In the meantime, shed fluid area to increase refrigeration, on cutter hub mill has rectangle or hemicycle infusion chamfer, can make area drifting fluid increases 20%~30% thereby, increase cooling fluid flow, get the cooling and lubricant result in cutting a course in order to increase. The cutting performance that deep aperture of bits of the platoon inside new-style fault tine gets experiments the cutting performance that for test and verify deep aperture of bits of the platoon inside new-style fault tine gets, undertook above all with common model the cutting force contrast that the fault ages deep aperture is gotten experiments, make the same score stability in order to analyse the cutting power volume of 2 kinds of broach and cutting; Had batch part next auger cut an experiment, in order to check quality of the durability of new-style broach, treatment and treatment efficiency. The comparative experiment of force of cutting of 2 kinds of broach uses the deep aperture that C630 lathe changes his costume or dress to get boring machine, workpiece material is 40Cr alloy steel, hardness HRC28~32, broach diameter is F58. 4mm. Use drill pipe to go up stickup resistor meet an emergency piece the change of the axial force in joining the method that measures an instrument measures cutting process and torque. From auger cut test data to make clear: As the accretion of feed F, the axial force of 2 kinds of broach and torque increase accordingly, but new-style deep Kong Zuan is compared common model force of axial of deep Kong Zuan is reduced on average 21% , torque is reduced on average 14.
7% . And, increase as feed, cutting force adds new-style deep Kong Zuan relatively slow, if become F=0.
When 03mm/r, the axial force of deeper than medium-sized Kong Zuan reduces new-style deep Kong Zuan only 25% , torque is reduced 24% ; And when F=0.
When 25mm/r, axial force and torque were reduced respectively 20.
7% with 22.
7% . Can see from this, new-style deep Kong Zuan is in the cutting process of big feed, cutting is lighter and smooth. Additional, also can see in the plan of change of axial force instantaneous that lays from the record, in bigger feed (F=0.
Below 25mm/r) , value of the peak with fluctuant force of cutting of new-style deep Kong Zuan, cereal is equivalent to only common model the 1/3 of deep Kong Zuan, explain new-style deep Kong Zuan is gotten cut smooth. This is gotten with new-style deep Kong Zuan centering can arise when cutting annular groove and centering arrive since awl instead it is consistent that double centering cuts action with stability getting. Got the comparative experiment that cuts oscillatory, durability and treatment quality to undertake to these 2 kinds of broach batch spare parts is gotten cut treatment to experiment, the choice undertakes be machininged actually in some oil machinery plant, the machine tool gets boring machine for T2130 deep aperture, workpiece material is 40CrNiMo5 alloy steel, hardness HB250~300, bore diameter is =50.
4mm. Graph comparative curve is in amplitude of 3 drill pipe award oil implement the drill pipe place of back end installs a dial gauge, measure broach the oscillatory circumstance in cutting process, age when the center (A is nodded) , oriented piece (B is nodded) reach decrease brace up piece (C is nodded) the amplitude that enters the drill pipe when getting and piece when getting (between D, E) the amplitude of drill pipe is comparative if the curve pursues 3 are shown. Can see, new-style deep Kong Zuan is being entered auger reach whole get the vibration in cutting a course to all be less than common model deep Kong Zuan. And after C is nodded, new-style deep Kong Zuan is decreased in its brace up piece after entering work, broach still has to decrease brace up stable process, make get cut torque rapid and abate to normal level, and common model deep Kong Zuan does not have this one process. Piece when getting (between D, E) , common model deep Kongzuan vibration begins aggravate, amplitude increases, and new-style deep Kong Zuan because difference of each tooth height is little, get fully at the same time almost, and have again decrease brace up piece protective action, can go out smoothly auger, amplitude increases very small. After 2 kinds of broach undertake bore of batch spare parts experiments, in same size hind when knife face wears away, the average bore length that deep aperture of bits of the platoon inside new-style fault tine gets can amount to 16m, it is common model the fault ages deep aperture gets bore length 2 times much. Undertake metrical to bore quality, the drills hole of new-style deep Kong Zuan, circularity error is compared common model deep Kong Zuan makes an appointment with small 3µm, bore diameter enlarge is many small 0.
04mm, hole size precision can achieve IT7~IT8, ra=1 of exterior surface roughness.
0~3.
2µm. The structure that epilogue discharges bits deep aperture to get inside new-style fault tine and blade it is reasonable that by cutting function the experiment is proved, can rise effectively get cut smooth stability, prolong broach service life, raise aperture to machine precision, it is broach of deep aperture of bits of the platoon inside a kind of new-style fault a tooth-like part of anything that has good application effect. CNC Milling
CNC Machining