Choose cutting tool to answer dosage of working procedure of the function of material of the process capability according to the machine tool, workpiece, treatment, cutting and other and relevant element choose cutting tool and knife handle correctly. Cutting tool chooses total principle is: Applicable, safe, economy. Applicable the goal that the cutting tool that is requirement place choice can achieve treatment, finish the purify of material, achieve booked treatment precision. If choose to have when rough machining enough the cutting tool that has sufficient cutting capacity greatly can be fast purify material; And when finish machining, come out to can process structural form entirely, want to use lesser cutting tool, machine each corner. Be like again, when material of cutting low hardness, can use high-speed steel cutting tool, and when material of cutting tall hardness, must want to use hard alloy cutting tool. What safety points to is in effective purify material while, the collision that won't produce cutting tool, break off etc. Should make sure cutting tool and knife handle won't collide to perhaps be squeezed with work look brush, cause the damage of cutting tool or workpiece. When the material of the horniness of cutting tool cutting with the very small diameter that is like lengthen, break off very easily, when choosing must discreet. What economy points to is can complete treatment with the smallest cost. Below the status that can achieve treatment likewise, the choice composes this inferior plan relative to put together, is not the cutting tool with the cheapest choice. The durability of cutting tool and precision and impact of cutting tool price are great, must of bring to sb's attention is, below most circumstance, although the cutting tool that has chosen raised cutting tool cost, but the treatment quality that brings from this and add what work efficiency leads to rise to be able to make total cost may more average than using cutting tool is lower, produce better beneficial result. If undertake rolled steel cutting when, choose high-speed steel cutting tool, its feed can achieve 100mm/min only, and the hard alloy cutting tool that uses same size, feed can achieve 500mm/min above, can shorten considerably handling time, although cutting tool price is higher, but total cost is lower instead. Normally the circumstance falls, first choice economy is good but dislocation cutting tool. When choosing cutting tool, consider to install adjustment convenient rate, rigid, durability and precision even. Below the premise that asks in contented treatment, of cutting tool dangerous extend length to be gotten as far as possible short, in order to raise the tigidity of cutting tool system. Commonly used to the part milling cutter makes brief specification below. 1. Milling cutter of cylinder of columnar milling cutter basically is used at horizontal milling machine to machine plane, it is integral type commonly, if pursue,1 is shown. Material of this milling cutter is high-speed steel, advocate cutting blade distributings to go up in cylinder, without deputy cutting blade. This milling cutter has the branch of thick tine and serration. Thick tine milling cutter, tine number is little, tooth strength is great, the space that hold bit is large, wear a number again much, apply to rough machining; Serration milling cutter, tine number is much, the job is smoother, apply to finish machining. ～ 100mm of D=50mm of limits of diameter of columnar milling cutter, tine counts Z=6 ～ 14, 45 ° of ～ of ° of =30 of helix angle β . When ° of =0 of helix angle β , helix tooth turns into straight tooth, the application on production is at present little. Graph 12. Milling cutter of face of face milling cutter basically is used on vertical milling machine to machine face of planar, step to wait. Of face milling cutter advocate cutting blade distributings to go up in the columnar face of milling cutter or taper seat, deputy cutting blade distributings to go up in the end panel of milling cutter. Face milling cutter can be divided by the structure solder for whole of milling cutter of integral type face, hard alloy clip of machine of type face milling cutter, hard alloy solders type face milling cutter, hard alloy but the form such as milling cutter of dislocation type face. The graph is shown 2 times is hard alloy whole solders type face milling cutter. This milling cutter is by hard alloy bit and alloy steel cutter hub are become via soldering, its structure is compact, cutting efficiency is tall, make more convenient. After tooth damages, very difficult rehabilitate, application of this milling cutter is not so much. Graph 23. Establish milling cutter to establish milling cutter to basically be used on vertical milling machine to machine face of groove, step, figuration face (use profiling) etc. The graph is shown 3 times establish milling cutter for high-speed steel. Should establish milling cutter advocate cutting blade distributings to go up in the columnar face of milling cutter, deputy cutting blade distributings to go up in the end panel of milling cutter, and end panel center has top opening, accordingly, feed cannot be done to move along milling cutter axial commonly when milling, can do feed exercise along milling cutter radial only. Should establish milling cutter to have the branch of thick tine and serration, thick tine tine counts 3 ～ 6, apply to rough machining; Serration tine counts 5 ～ 10, apply to semifinishing machining. This diametical range that establishs milling cutter is 80mm of φ of φ 2mm ～ . Petiole has straight handle, Mohs awl handle, 7:2A variety of forms such as 4 awl handle. Should establish milling cutter application wider, but cutting efficiency is inferior. Graph 34. Milling cutter of keyway of keyway milling cutter basically is used on vertical milling machine to machine round head to close keyway, if pursue,4 are shown. The be similar in shape outside this milling cutter establishs milling cutter, end panel does not have top aperture, end panel tooth from outside the circle leaves to axes, and helix angle is lesser, enhanced strength of end panel tooth. The cutting blade on end panel tooth gives priority to cutting blade, the cutting blade on columnar face is deputy cutting blade. When machining keyway, measure lesserly along feed of milling cutter axial first every time, next again along radial feed, such for many times iteration, with respect to the treatment of achievable keyway. As a result of this milling cutter wearing away is to be in end panel and stand by end panel outside round part, repair so when grinding, should repair only grind blade of end panel cutting, such, milling cutter diameter can keep changeless, make treatment keyway precision taller, milling cutter life is longer. The diametical limits of keyway milling cutter is 63mm of φ of φ 2mm ～ . Graph 45. 3 blade milling cutter basically uses 3 blade milling cutter on horizontal milling machine to machine face of groove, step to wait. Of 3 blade milling cutter advocate cutting blade distributings to go up in the columnar face of milling cutter, deputy cutting blade distributings to go up in two end panel. This milling cutter can be divided by tooth structure age for straight tine, fault and mount a tooth-like part of anything 3 kinds of forms. The graph is shown 5 times is straight tine 3 blade milling cutter. Structure of this milling cutter is simple, make convenient, but the horn before deputy cutting blade is zero, cutting condition is poorer. Limits of diameter of this milling cutter is 50mm ～ 200mm, 40mm of width 4mm ～ . Graph 56. Milling cutter of angle of angle milling cutter basically is used on horizontal milling machine to machine all sorts of angle chamfer, cant to wait. The material of angle milling cutter is high-speed steel commonly. Angle milling cutter differs according to itself appearance, can divide milling cutter of dual role of milling cutter of milling cutter of the blade that it is sheet, asymmetry dual role and semmetry 3 kinds. The graph is shown 6 times is only part milling cutter. Blade of the cutting on taper seat is advocate cutting blade, the cutting blade on end panel is deputy cutting blade. Limits of diameter of this milling cutter is 40mm ～ 100mm. Graph 67. Milling cutter of mould of mould milling cutter basically is used on vertical milling machine to machine surface of mould antrum, three-dimensional figuration to wait. Mould milling cutter differs by working section appearance, can divide for cylindrical milling cutter of head of ball head milling cutter, round cone-shaped ball and conic form establish milling cutter 3 kinds of forms. It is cylindrical that the graph is shown 7 times ball head milling cutter, the graph is shown 8 times is milling cutter of head of conic form ball. The round cylinder in these two kinds of milling cutter, taper seat and spherical the cutting blade that go up all gives priority to cutting blade, feed can be done to move along milling cutter axial not only when milling, also can do feed exercise along milling cutter radial, and ball head and workpiece contact often are a bit, such, this milling cutter falls in the control of CNC Milling, can machine an all sorts of complex figuration surfaces, utility of this milling cutter is so distinctive, have development outlook very much. If the graph shows round taper 9 times to establish milling cutter its action and establish milling cutter basic and identical, it is the cone that this milling cutter can use itself only, machine those who give mould speech to give modular role conveniently. Graph 7 graphs 8 graphs use on 9 machining center establish milling cutter to basically have 3 kinds of forms: Ball head knife (R=D/2) , the knife that carry mill (R=0) with R knife (R<D/2) (common says " bovine bazoo knife " or " round nose knife " ) , among them D is knife horn radius for the diameter of cutting tool, R. Certain cutting tool contains certain taper A possibly still. When choosing cutting tool, should make the dimension of cutting tool and be gotten used to by the exterior dimension photograph of treatment workpiece. Of cutting tool diameter choose basically depend on the treatment dimension of the norms of equipment and workpiece, still need to consider cutting tool place to need power to should be in limits of machine tool power. In production, the treatment of outline of cincture of week of planar spare parts, often use establish milling cutter; When milling is planar, should choose upright milling cutter or face milling cutter; When machining protruding stage, groove, choose high-speed steel to establish milling cutter; When machining semifinished product surface or rough machining aperture, can choose the corn milling cutter that sets hard alloy bit; A few righter establish bodily form face and change the treatment of appearance of bevel angle outline, often use ball head milling cutter, annular milling cutter, cone-shaped milling cutter is mixed dish of form milling cutter. Planar milling should be chosen do not grind hard alloy to carry milling cutter again or establish milling cutter, can turn the milling cutter that it is a face. Use 2 times commonly take a knife, walk along a knife to had better use thick mill of upright milling cutter for the first time, edge workpiece surface takes a knife continuously. Had chosen the diameter of the width that takes a knife every time and milling cutter, make lapping defect does not affect precision of mill of essence of life. Accordingly, mental allowance is big inhomogenous when, milling cutter diameter should choose a little bit small. When finish machining, milling cutter diameter should choose a little bit big, best can include the whole width that machines a face. When exterior demand is high, still can choose to use the bit that has Xiu Guangxiao fruit. In real work, planar finish machining, use commonly but milling cutter of dislocation close tooth flank, the appearance that can achieve ideal machines quality, can come true to be ground with mill generation even. Densely covered tooth makes feed rate rises greatly, improve cutting efficiency thereby. When essence of life cuts plane, can install 6 ～ 8 tooth, the cutting tool with big diameter can have more than 10 tooth even. Treatment airspace curved surface and change when appearance of bevel angle outline, as a result of the spherical end of ball head cutting tool ministry cutting speed is 0, and when taking a knife, every two knives between, treatment surface is impossible to overlap, total presence was not machined the part of purify. Every two knives the space between is larger, was not jumped over by the part of treatment purify much, its height (call normally " rudimental height " ) taller, the error that processes the surface that come out and academic surface is bigger, exterior quality is poorer also. Treatment precision demand is higher, pace taking a knife grows and cutting row spacing is smaller, process designing efficiency is lower. Accordingly, below the premise that should ask in contented treatment precision, increase knife pace to grow as far as possible with row spacing, in order to improve process designing and treatment efficiency. And reach in 2 axes 2. In 5 axes treatment, to improve efficiency, answer to use upright milling cutter as far as possible, as a result of identical treatment parameter, use ball head knife to add labour union to leave greater rudimental height. Accordingly, below the premise that in guarantee against happening interference and workpiece are not cut too, no matter be the rough machining of curved surface or finish machining, answer knife of first choice crop or R knife (of the horn that bring a circle establish milling cutter) . Nevertheless, because crop establishs the treatment of milling cutter and ball head knife,effect is apparently different if really, when curved surface form is complex, to avert interference, the proposal uses ball head knife, adjust good treatment parameter to also can achieve better treatment result. He Lixi knife basically uses the knife carrying mill that sets hard alloy bit at machining protruding stage, groove and box mouth face. To raise the treatment precision with wide chamfer, reduce the sort of milling cutter, the diameter should be used when treatment wider than groove small milling cutter, first the intermediate part of mill chamfer, next radius of recycle cutting tool is compensated (or call a diameter compensation) the function undertakes to groovy both sides mill is machined. The treatment of higher to the requirement tiny position, can use knife of hard alloy of whole form of characters or letters, it can obtain taller treatment precision, but notice cutting tool is dangerous litre cannot too big, otherwise cutting tool not only amount letting a knife is large, easy wear away, and can have the risk that break off. Milling dish the circumjacent outline of kind of spare parts is used commonly establish milling cutter. The uses cutting tool radius that establishs milling cutter must be less than the radius of the smallest curvature of the outline inside the spare parts. 0 what take radius of the smallest curvature commonly.
8 ～ 0.
9 times can. The treatment height of the spare parts (the deepness of penetration of a cutting tool of Z direction) the radius that had better not exceed cutting tool. If when face of mill semifinished product, had better choose hard alloy ripple to establish milling cutter, below the condition that it allows in system of machine tool, cutting tool, workpiece, can undertake puissant cutting. When bore, should use central getting or ball head knife to hit heart hole first, in order to is brought broach. Need deepness Z to place with lesser broach bore first, the bit with older reoccupy undertakes bore, the bit that needs with place finally undertakes machining, in order to assure the precision of aperture. When undertaking deeper Kong Jia is versed in, should note the refrigeration of broach and platoon bits problem particularly, use deep Kong Zuan to cut a loop to dictate G83 undertakes process designing commonly, can be versed in after entering a paragraph, broach exits workpiece to undertake discharging bits and refrigeration quickly; Be versed in again into, make till hole depth getting is cut,discharging bits finish again. Cutting tool of machining center machine tool is a more complex system, how to undertake be choosinged correctly according to actual condition, it is in CAM software the parameter with correct set, personnel of numerical control process designing must master. Mix to structure of machining center cutting tool only choose have sufficient understanding and knowledge, and accumulate experience ceaselessly, in real work ability is applied neatly, raise work efficiency and manufacturing benefit to assure safe production. CNC Milling
CNC Machining