Get a needle to repair grind with in the bore on columnar face

Get a tip repair the technologist Mike Plankey that worries Kennametal company to be aimed at on cylinder bore offers a few opinion. Above all, bore fixed position can be gotten with the center in workpiece surface, make bore has an accurate beginning to nod, another opinion is to use a cross to repair the bit getting a tip that worry, it can make plunge knife at the beginning cutting immediately surface of workpiece of bring into contact with, can prevent bore amlposition. Common get a needle to agree the SE of accept gets pointed helix to get pointed paraboloid to get pointed cross / 4 facet get pointed Bickford to get Jim Geske of senior technician of company of pointed accurate broach to say, to the broach in the bore on cylinder, at least 4 kinds get pointed blade to wear type from centering is very effective: Helicoid is repaired grind, Bickford is repaired grind, 4 facet are repaired grind and the cross is repaired grind. Bickford repairs grind and helicoid repairs grind some likeness: Helix shape gets a tip, if the hole with tolerancepublic errand stricter requirement is drilled on thin wall canal, repair with Bickford wear type may better, because can see from the Kong Xian inside the spare parts,get pointed prominent place. Repair with these two kinds grind type to repair grind get a tip, point of blade of its horizontal stroke forms one convexity, gift thereby it from centering ability. However, geske says: "Bickford is repaired grind to broach of integral hard alloy it is improper, because this kind is repaired,grind, need the diamond emery wheel of about 9 kinds of different diameters, cost is too high. " right now Lv of tool manufacturer take an examination chooses 60 ° or 90 ° (corner of the predestined relationship outside be being added at broach is in) helicoid is repaired grind. 4 plane are repaired grind also repair with Bickford grind and helicoid is repaired grind similar, but it has two advocate hind horn mixes two the 2nd hind 4 plane that horn forms, these 4 plane form the sharp drop of one each centering. Geske says, 4 plane repair grind also have two kinds of type: All sides fold and all sides are handed in in the center. Fold advocate from the back width is as identical as the ply that get a heart. At this moment advocate hind the horizontal blade bevel that horn decided broach, nature is hind part is larger, horizontal blade bevel is bigger also. Raised to be in apparently bore, geske recommends the type that is made at the center with all sides. Because the manufactory hopes all advocate, minor flank on the center that as it happens makes at broach, in order to assure from centering ability. The Don Strubler assistant manager of Performedge company says when speaking of a cross trimming the good point that grind, broach of most hard alloy is repaired with the cross grind or S long grind. The cross is repaired grind the axial pressure that reduced broach, get a needle to enter work light, can from centering, it is very important that this cuts Kong Shi of on-line of center of circular spare parts to getting. The cross repairs grinding is a kind repair commonly usedly wear type: P3, P5 and P9. P3 gets pointed horn to be 135 ° , p5 is 118 ° , and P9 is cobaltic the P3 broach of kind of hard alloy make it, the horn that get a tip also is 135 ° . The cross is repaired worry bit from centering function very good, for example, diameter 6.

35mm ～ 12.

The broach of 7mm, the cross is repaired grind form to have 0 only.

05mm ～ 0.

The ply getting core of 2mm, as pinpoint and same, but from centering. Choiniere of Superion company director says, to be in raised apparently bore, make the sharp drop of one each centering on broach normally, contact workpiece in order to ensure this needle is nodded at broach external diameter first, if handlers wants to be in,tilt namely of 15 ° raised apparently bore, the cutting blade banking angle of so all broach is spent must be more than 15 ° , so that make broach gets a needle to be able to contact workpiece surface first, otherwise, handlers must the cutting tool that have the aid of has smoother Duan Ren (if establish milling cutter) first mill, be in commonly on the cant that is more than 6 ° when bore, application establishs milling cutter to have prior operation, deflection arises when can preventing bore or bring slant. According to Introduction Geske, the deepness that chooses broach and bore is concerned. Because this will affect the type of broach (if broach is groovy chamfer form, still be) of parabola chamfer form. When hole depth is more than 4 times diameter, recommend with broach of parabola chamfer form. Its groove is wider, allow to use rapidder cutting rate and bigger hole depth. Once cutting tool design gets a needle to enter workpiece surface, the geometrical figure that gets a tip is in minor position instantly. The element that other needs to consider comes out now with respect to protruding, function of bits resembling a platoon and tigidity. Broach needs those who have proper figure to get a tip not only, it still must maintain enough tigidity from beginning to end. Raised surface bore waits in columnar face, use shorter bit almost, especially those process that use head. The Tom Trost of sale department assistant manager of a CJT KOOICarb company that produces bit of integral hard alloy says, the bit of hard alloy of short length whole that this company produces, the 30% horn getting a tip that are 140 ° . TiN coating, cross builds the groovy product that grinds broach to already became this company market to go up. When designing broach, should the function discharging bits of mature broach. To getting the bit of deepness of 3 ～ 4D, strubler says, most broach manufactory broaden the groove of its broach. In last few years, these manufacturer learned to operate emery wheel adroitly, make improvement groove form. To hard alloy broach, use groove bottom parallel or be lesser core thick increment, such groove become bigger. And to high-speed steel broach, as it happens is contrary, need tigidity to hold place, core thick increment is bigger and groove becomes lesser, the space that discharge bits is little, cause the difficulty that discharge bits. Speed, feed and cooling Strubler emphasize, beginning to get fashionable, want to use slower feed. Also use a few special method or program sometimes, if main shaft rotates, feed is used " peck attack " means, or repeat feed, outside aperture is being exited later. Strubler says, this is opposite actually hard alloy broach is adverse, because become when go back broach, one part cuts bits to stay in hole bottom, and hard alloy broach is cut with high speed, tall feed again fashionable collision cuts bits, can cause broach damage. To solve this one problem, recommend auger brief feed halt is joined in cutting, next resumptive feed. About using cooling fluid issue correctly, trost says, most operation personnel is when bore, oil of direct use cutting is cooling, but the likelihood gets of the problem such as environmental protection restrict. The emulsion refrigeration effect that uses oil and water is very good. Used when cutting more lubricant, make main shaft light, reduced power demand, reduced attrition. CNC Milling