The assess of character of appearance of emery wheel form and its are reasonable match

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The grinding function of emery wheel depends on not only emery wheel structure is characteristic, if grind bead, granuality and hardness to wait, and more depending on the form appearance feature of emery wheel surface. Character of appearance of form of emery wheel surface is to point to emery wheel apparently the instantaneous condition of the cutting blade that wear bead, call instantaneous character again, distributing like what grind a cutting blade, the wear and tear that rubs bead, broken and fall off and of the space that hold bit jam etc. Instantaneous character changes as the change of grinding time in grinding process, accordingly, must undertake reasonable assess to character of appearance of emery wheel form. Want to make emery wheel acquires good grinding property, need fibrous root occupies specific grinding requirement, those who have character of emery wheel structure and form appearance character is reasonable match, make the grinding of emery wheel surface achieves groove. The face of geometrical parameter emery wheel that the assess 1) of character of appearance of form of 1 emery wheel wears a cutting blade has a lot of volume the differ, cutting blade wearing bead that distributings randomly, the geometry that grinds a cutting blade for the description is characteristic, can define the geometrical parameter of the cutting blade that wear bead: Grind blade before horny Gg, horny Ag is reached after if the graph shows) 1 times,grind Rb(of radius of blade blunt circle, apparent, the shape size that wears bead reachs his the geometrical parameter that in emery wheel apparently azimuth decided to grind blade, affect the cutting performance that grinds blade then. Graph the appearance that the geometrical parameter of the 1 cutting blade that wear bead grinds a cutting blade is extremely irregular, go to the lavatory for the analysis, but the appearance that wear bead Utopian, the simplifying cutting blade that wear bead classifies as follows: (1) conic or arris is cone-shaped; Undertaking thick nap or when emery wheel hardness is inferior, easy form this kind of appearance; (2) is globose; Round horn radius is 10 ～ 20µm; (The circle with 3) round most advanced horn is cone-shaped: Grind the result of a nick, grind bead to cut deep big when, its cutting action is close to Yu Yuan taper; Cut deep hour, cutting is adjacent at globose; (4) flat-roofed circle is cone-shaped: The coping that wear bead by the appearance of wear and tear, hour of lead of emery wheel hard nap is easy form this kind of appearance. From the consideration of sex of sharp edge acute of the cutting blade that wear bead, conic or arris is cone-shaped (the conic form with 1) and round most advanced horn (3) nears the strong record at wearing bead actually, sharp sex is better; Globose (2) and area top circle are cone-shaped (4) nears the lump at wearing bead actually and strong record of wear and tear respectively, sex of sharp edge acute is poorer. The dimension that wear bead heals small, eg of part of center of the cutting blade that wear bead heals small, grind sex of acute of bead sharp edge to had healed. Grinding a direction on emery wheel working face and position distributing randomly, from the point of statistical viewpoint, the azimuth that wears bead is affected to grinding the around horn of blade not quite. Grind blade before horn basically depends on Eg of its center part, the top part Eg that wears bead commonly heals small, those who grind blade before horny Gg heals big. 2) grinds a cutting blade distributing the diagnostic parameter that the cutting blade that wear bead distributings basically has: (1) grinds bead span Lg. Show emery wheel is circumferential on early or late the arc of 2 cutting blade is apart from the photograph adjacent with grinding bit samer work, express to grind the basic parameter of distributinging condition of bead cutting blade; (2) grinds B of width of platform of bead wear and tear. Point to perpendicular grind a cutting blade at the wear and tear of cutting direction small platform width, express to grind the basic parameter of status of job of bead cutting blade. By afore-mentioned diagnostic parameter calculable the cutting blade wearing bead that gives area of the unit on emery wheel working face counts Mg(＝ 1/Lg2) , but grind a cutting blade to go up in emery wheel working face distributinging is inhomogenous, and on any account is uneven, have the definition problem of a cutting blade that wear bead consequently, if peak cereal is tall the Dh that spend difference is dinky, because there is the enough space that hold bit between 2 protruding peak, can have the effect of a cutting blade only actually, 5µm of ≥ of general provision Dh or Dh ≥ (Fr/2)(fr -- radial feed) ability calculates for two cutting blade. As a result of grinding process medium motion concerns. Also make embedded certain of deepness grind blade to won't attend cutting, the number grinding blade that joins cutting actually consequently (grind a cutting blade effectively to count) greatly little the number wearing bead at emery wheel surface. Set the span that wear bead to be Lg, a cutting blade is ground before a cutting blade is being ground to compare after low on direction of emery wheel radius Dh, for the condition that grinds a cutting blade effectively type (1) is knowable, when character of appearance of emery wheel form is changeless, as the accretion of workpiece speed Vw and cutting deepness Ap, vs of emery wheel speed and Ds of emery wheel radius are reduced, grind a cutting blade effectively number general grow in quantity. Additional, grind number of bead cutting blade effectively to return concern with condition of appearance of form of emery wheel surface, number of emery wheel size heals big, emery wheel hardness heals tall, fd of lead of the nap when nap and nap deepness Ad heal small, grind number of bead cutting blade effectively to also heal much. The statistical analysis of character of appearance of form of 3) emery wheel is used touch stitch to measure appearance of form of emery wheel surface, obtain emery wheel the form appearance of surface of the emery wheel on circumferential direction pursues (if pursue,2 show) . The bag in form appearance graph contains the cutting blade that wear bead and abut look bits chamfer, grind a cutting blade and look bits chamfer to go up in emery wheel radial distributing, usable random is given the cutting blade wearing bead of horizontal above and the radial of the chamfer that hold bit accumulate height distributing -- radial probability distribution will express, the cutting blade wearing bead of this consideration in distributinging to pursue for form appearance respectively and the percentage that hold bits chamfer sum total. Graph the curves of 3 radial probability distribution that are the cutting blade that wear bead and look bits chamfer, in emery wheel surface the outerest (namely highest horizontal over) , the radial probability distribution of the cutting blade that wear bead (per cent) for 0, and the radial probability distribution of the chamfer that hold bit is 100% ; In emery wheel surface most lining (namely lowest is horizontal under) , the cutting blade that wear bead and the probability distribution of the chamfer that hold bit criterion just contrary. Graph the form appearance graph of surface of 2 emery wheel pursues the cutting blade wearing bead that the curve of radial probability distribution of the 3 cutting blade that wear bead and look bits chamfer passes appearance of form of surface of statistical emery wheel and the radial probability distribution of the chamfer that hold bit, can analyse the distributinging characteristic of the cutting blade that wear bead and look bits chamfer, achieve the goal that shows character of appearance of emery wheel form with probability distribution (if pursue,3 show) . To the sharp emery wheel of new nap, the curve of radial probability distribution of the cutting blade wearing bead of appearance of form of emery wheel surface is polynomial model, of the cutting blade that wear bead distributing tend concentration is in at brim of emery wheel surface layer, center at emery wheel work area namely, and the curve of radial probability distribution of the chamfer that hold bit is gauss model, the chamfer holding bit of work area of emery wheel surface is corresponding little; Blunt to grinding serious emery wheel, circumstance criterion just contrary. Of character of appearance of form of 2 emery wheel reasonable match should make emery wheel surface acquires good grinding property, the structure that can output parameter to choose emery wheel by asks grinding is characteristic, emery wheel of reasonable nap, make character of appearance of form of emery wheel surface achieves maximize. Mix with accurate grinding below the grinding of titanium alloy is exemple, those who analyse appearance of form of emery wheel surface match a question. 1) nicety and mirror grinding nicety and mirror grinding are the small blade that grinds bead to go up by emery wheel undertake minim cutting and attrition polish and finish. Apparently small blade arranges emery wheel of the requirement when grinding should orderly, broken want even, number of unit area small blade wants much, wait for tall sex to be close friends. For this, must choose reasonable emery wheel construction, undertake careful emery wheel nap. The intensity as a result of corundum abrasive and tenacity all taller, after careful nap easy form the small blade with wait for tall sex good, consequently when nicety and mirror grinding, can choose corundum abrasive; To granuality and bond, can choose thick granuality commonly (emery wheel of bond of pottery and porcelain of 46 ～ 80#) or fine granuality (emery wheel of bond of colophony of 240 ～ 260#) . The small blade that former course forms after careful nap gives priority to body with cutting, apply to accurate grinding commonly; Latter because the stretch action of bond, can make small blade is in workpiece apparently attrition polish effect is apparent, apply to mirror grinding commonly. Fall off to prevent what produce chunk in grinding process to wear bead, should choose harder emery wheel. For in emery wheel apparently obtain good small blade, can choose most advanced the sheet of sharp edge acute nap of King Kong jade implement, undertake careful nap with turning law. Popularly, nap heals careful, the small blade number that bead wears on emery wheel surface layer heals much, and incline to is centered at emery wheel surface layer, it is good to wait for Gao Xingyu, character of appearance of form of emery wheel surface has healed; When nap rate is fixed, emery wheel speed heals tall, the small blade that grinds bead to go up heals concentrated, wait for tall sex to also had healed, character of exterior form appearance has healed. When small blade cutting, just began small blade to grind essence of life treatment apparently rudimental protruding sharp edge cut away, reach as small blade passivation jam, the attrition action of small blade increases, the joint action of the cutting of small blade and attrition finishs the accurate grinding of workpiece surface. Because constant grinding pressure exists between emery wheel and workpiece, already the small blade of passivation undertakes attrition polish to workpiece surface, grind a peak of will microcosmic protruding to compress pad namely in the sunken Gu Zhi at machining the surface, workpiece surface surface roughness decreases further, lens face is formed gradually. This shows, those who grind a small blade and cutting dosage is reasonable matching also is a decisive issue, if grinding deepness Ap must be controlled,be inside the size scope of small blade, ability produces its beneficial result. Conglutinate of surface of the emery wheel when the alloy of grinding grinding titanium of 2) titanium alloy jams serious, make the sex of sharp edge acute of the cutting blade that wear bead drops, emery wheel grinds number of bead cutting blade apparently effectively to decrease, grinding comparing drops. Be out of shape as a result of what titanium alloy conglutinate jams complex, make grinding force and grinding temperature higher, grinding burn is a kind of the most serious phenomenon when grinding titanium alloy, when choosing emery wheel consequently, optional choose sex is fragile and sharp green carborundum (TL) grinds bead and cerium carborundum (TS) wears bead (latter grinding effect excel is former) . Additional, because cubic nitrogen changes boron (the thermal stability that CBN) wears bead is good, cutting performance is good, reason CBN grinds bead is a kind of ideal of grinding titanium alloy to wear bead. The grinding that to facilitate emery wheel conglutinate jams, appropriate chooses granuality big (the soft emery wheel of 46 ～ 80#) . If organize a structure to consider from emery wheel, can choose atmosphere aperture or much more stomatic loose emery wheel. After emery wheel passes the successive nap of diamond gyro wheel, emery wheel surface forms the sharp cutting blade that wear bead and larger look bits space. Because wear a size big and the existence in the organization is stomatic, decreased to grind density of bead cutting blade thereby, added look bits space, improved refrigeration to come loose hot condition. The gender is fragile the soft emery wheel that wears bead, what easy also in grinding process generation wears bead is broken with fall off, can maintain the sharp sex that wears bead, make the between-mean distance wearing bead of emery wheel increases somewhat, be helpful for reducing emery wheel conglutinate to jam quantity and grinding burn. To avoid the grinding burn of grinding titanium alloy, the method of a kind of effective is to use helix chamfer emery wheel. Proportion of part of emery wheel groove heals big, the working section proportion that contacts with work look heals small, emery wheel grinds number of bead cutting blade effectively to decrease, grind bead to arrange more tend reasonable, decrease likely thereby slippery brush, the attrition power that plough place produces and useless result, make the cutting ability that wears bead is in groove, prevent the happening of grinding burn. 3 last words by afore-mentioned analysises knowable, character of appearance of emery wheel form is one of important input parameter in grinding process, have conclusive effect to the grinding function of emery wheel, the stand or fall of character of appearance of form of emery wheel surface, must have reasonable opinion according to specific grinding requirement, and the groove that should achieve emery wheel grinding, what must have character of emery wheel structure and form appearance character is reasonable match. If want to make clear condition of character of emery wheel structure, nap and appearance of emery wheel form completely characteristic causal and character of appearance of form of emery wheel surface and the correlation that grinding outputs parameter, still a lot of jobs want to do, once these jobs are finished, can forecast grinding result by character of appearance of emery wheel form and design grinding process by the grinding result of the requirement, add those who add grinding process to forecast a gender to reach greatly thereby from adaptability. CNC Milling CNC Machining