Use high speed to do promotion of type cutting technology to produce can

6% , cutting fluid cost saves 10% ～ 12% ; Treatment precision is tall, assure ± of craft requirement D 0.

02mm, exterior surface roughness is good; Through adjusting cutting force, overcame what vibration causes to fight force, be helpful for machining journal dimension crankshaft of big, qualitative generous; Stimulate Zhen Pin rate is high, cutting is smooth, basically eliminated high frequency with low frequency brace up knife, rate of machine of bit collapse blade fell 70% , exterior remains stress is little; Saved cutting fluid to use reach uphold charge, avoided the cutting fluid pollution to the environment and the harm to human body at the same time. High speed does the technology of type cutting to ask forged steel crankshaft belongs to difficult treatment material, its have strength tall (650MPa< σ B<900MPa) , hardness is big (200<HB<310) , quality is great (100kg of about 60 ～ ) , lopsided quantity and jumpy Yi Chao's poor characteristic, working procedure of fine vehicle main shaft should realize high speed to do type cutting, have very high demand to machine tool, cutting tool, assure technology measure even at the same time, solve journal brace up knife, prolong cutting tool life, reduce the relevant difficult problem such as finished cost. 1. To the technology of the machine tool machine tool of demand numerical control is the first requirement that realizes high speed cutting and premise safeguard, crankshaft treatment is different from other work treatment, sometimes rotate speed can be achieved minutely thousands of turn. The equipment that machines crankshaft normally should be had slideway, tip and turn the tower is rigid precision of good, circumgyrate is tall and can offer enough torsion. These elements are to assure a machine tool the main demand that to crankshaft this kind of special workpiece has high speed cutting, this also is the requirement that the attention needs particularly when purchasing a machine tool. 2.

Basically be to the invalidation form of the cutting tool when the cutting of technical requirement high speed of cutting tool function wear away and broken, cutting tool should part according to grind blunt standard and dosage of cutting of broken life choice to decide cutting tool life. Through experimenting jointly with tool manufacturer for years, we ask to sum up as follows to function of cutting tool of coating hard alloy: (The cutting tool that 1) chooses proper coating technology to use technology of MT-CVD+HT-CVD compound coating is integrated the advantage of a variety of coating material, have tenacity of admirable hot rigid, high temperature and wearability, can solve high speed effectively to do the difficult problem with small service life of cutting tool of type cutting alloy steel. When the hardness with enough Nextpage(2) and cutting of tenacity high speed, muscularity of cutting of cutting tool susceptive, the hardness of material of requirement cutting tool is the 3 times above of workpiece material hardness at least, hardness of general coating razor blade is more than HRA89.

0, the compound coating that via the surface Jiang Ren handles is microscopical hardness amounts to 2 600HV. If seek data of tall hardness cutting tool one-sidedly, easy cause bit collapse blade, cutting tool material must want to have enough tall tenacity. (The high temperature of cutting of very dry type can comprise 3) thermochemistry stability between the chemical endophilicity of material of aggravate cutting tool and crankshaft material and material of the element diffuse, deliquescent, the inert diaphragm that among them Al2O3 coating forms in cutting process can rise to fight oxidize and be able to bear or endure diffuse tatty action, especially α - Al2O3 can issue the chemical stability that can keep good and thermal stability in high temperature, prolong cutting tool life thereby. (Coating of TiN of surface of low coefficient of friction can replace 4) the lubricant action of cutting fluid, drop a knife, bits, knife, the heat in metal cutting that workpiece attrition produces, raised the durability of cutting tool at the same time. Additional, break bits implement one of elements that appearance also is influence cutting temperature. Knife, bits contact time is long, cutting temperature is elevatory fast, cutting blade easy passivation. 3.

The long and thin axis that to processing the technique of craft requirement crankshaft regards a kind of special appearance as (L/D ≈ 9) , top pressure crosses congress to cause crankshaft to bend, high speed can produce very great inertial and centrifugal power in cutting process, brace up knife phenomenon unavoidable, accordingly, must be opposite function of angle of cutting parameter, cutting tool, machine tool and crankshaft material undertake reasonable collocation character, ability solves problem of knife of numerical control Che Zhen, make sure each dimension satisfy craft requirement. (The reasonable arrangement of 1) craft parameter is solved brace up the premise that knife problem is cutting of implementation high speed. Well-known, closely related speed of knife of numerical control Che Zhen and main shaft rotate speed, feed and quantity of back penetration of a cutting tool. Through advocate cutting force, feed force and back force are right brace up the influence of the knife undertakes comparative (if express 1) , we discover: Enough cutting force talent must be offerred to overcome what vibration causes to fight force in cutting process, make sure cutting tool undertakes smooth cutting. Express 1 cutting force to be opposite brace up the cutting dosage with the material effect of the knife because the element such as qualitative, appearance concerns crankshaft material far apart, do not do give uncecessary details here. Brace up after knife problem is solved, the treatment efficiency of the crankshaft before quenching to produce car of essence of life adequately, the crankshaft after avoiding fine vehicle to quench at the same time produces second birth flutter, influence essence grinds efficiency of main shaft grinding, vehicle of the main shaft before needing to quench to vehicle of thick car main shaft, fine, fine (or half essence is ground) the mental allowance of the main shaft after quenching undertakes reasonable allocation. The choice of surplus what because of product ability precision of qualitative, machine tool reachs an axis is jumpy and different. Often press the computation that push a way: Mental allowance is neck of the main shaft after fine vehicle quenchs: After fine vehicle 4 advocate jumpy quantity + 2+A of × of Dao Wen deepness (A=0.

2 ～ 0.

5 Mm) ; Mental allowance is neck of the main shaft before fine vehicle quenchs: After quenching 4 advocate jumpy quantity + 2+A of × of Dao Wen deepness (A=0.

2 ～ 0.

5 Mm) . The logical choice of parameter of Nextpage(2) cutting tool chooses parameter of appropriate cutting tool geometry in process of high speed cutting, can make more heat in metal cutting are cut bits is taken away. Need to notice the following commonly: ① links demand of technology of dry type cutting, high speed cutting is chosen than groovy cutting tool slightly big before horn can obtain blade of cutting of sharp, coriaceous, in order to decrease before knife face and the attrition that cut bits. 15 ° of ～ of ° of the general 0=12 that choose γ , in view of make up for big before horn is right of the intensity of cutting blade weaken, bit needs point aggrandizement, main aggrandizement form is blade of face of the knife after blunt round blade is mixed is ground lose edge, width pouring arris is made an appointment with 0.

1 ～ 0.

3mm. Because material is qualitative different, width pouring arris and crankshaft hardness become inverse ratio. The blade before forged steel crankshaft is general and incorrect has edge. The choice of the horn after ② basically considers to decrease workpiece and hind the attrition of knife face. The negative blade dip with bigger ③ can enhance the strength of knife head, raise cutting sword fight concussion ability, 8 ° of ～ of ° of S=5 of general choice λ . ④ pledges according to crankshaft material and cutting dosage chooses to break bits suitably implement, knife, the attrition state that bits contacts length to be able to affect cutting directly, increase attrition force to be able to restrain vibration effectively appropriately. (Because precision of treatment of machine tool of thick car main shaft is low,3) round horn machines craft, to assure axial dimension, the surplus that the mental allowance of side stage and R horn compares journal slightly big (if pursue,show 1 times) . When lathe tool fast feed arrives when R horn area, every increase side stage surplus 0.

01mm, quantity of back penetration of a cutting tool increases accordingly 1.

2 times, cutting force increases 3 times, bring about cutting blade damaged, when machining material to reach the crankshaft material after quenching more forcedly character especially. Accordingly, the directest settlement method is the mental allowance that reduces stage of side of thick car main shaft as far as possible perhaps is before neck of fine vehicle main shaft to side stage head is cut. Below the circumstance that Chanzhijia is versed in metre allows, can reduce cutting speed and feed appropriately, can maintain the smooth stability of the cutting when high speed feed so, the machine rate with bit broken collapse can reduce 45% . Go up character from the material of cutting tool consideration, can choose the cutting tool stuff with good tenacity, collapse blade phenomenon is attainable change apparently, bit life can rise 30% . Graph 1 round horn is machined (4) brace up of knife control crankshaft brace up knife form basically has two kinds, one kind is the scale shape Zhen Wen that causes by high frequency vibration, another kind is the whorl shape Zhen Wen that causes by low frequency vibration. High frequency brace up the position that the knife appears has random sex, not big to influence of working procedure of fine vehicle main shaft, and low frequency brace up the knife often appears in 2, 3, a side of neck of 4 main shaft or two side, serious low frequency brace up the knife may produce waste product, because this must try,solve. Knife of numerical control Che Zhen is not simple cause because of certain link occurrence problem, by many elements joint action forms it, if every main problem cannot get be settlemented effectively be meetinged causing brace up knife, because this needs to undertake to oscillatory reason whole is analysed, solve problem one by one. The following respects require special attention: Out of tolerance of ① lopsided quantity. Main shaft high speed rotates in the process, lopsided quantity arises hand in change stress can cause oscillatory from mental efforts ripple disorder, cause serious low frequency brace up knife. Watch 2 in be treatment process, appear serious brace up the crankshaft of the knife is lopsided measure calm value. If appear,this circumstance should adjust central aperture private plane in time, make sure dynamic balancing is measured not out of tolerance. Nextpage watch appears in 2 treatment process serious brace up the crankshaft of the knife is lopsided measure the ② that decide a value to adjust height of point of a knife. When machining softer crankshaft material to pledge, point of a knife should slightly under central line, pledge when crankshaft material harder when point of a knife should line of center of summary prep above, specific reduce or raise height of point of a knife even the wear out condition of face of the knife after the horn after the basis loses the width of arris to reach will decide. Prevent top stress concentration. Enter state of high speed cutting when the machine tool, of force of gravitational, cutting, centrifugal force and lopsided quantity generation hand in change stress can be centered to the tip, the counterforce of its join forces can make crankshaft bends be out of shape, jumpy out of tolerance. The generation on the journal that can approaching a center commonly is serious brace up knife. Be aimed at this phenomenon, can carry the stretchy amount that reduces a tip, adjust top pressure value to reach those who enhance a tip to fight Zhen Jiang to spend will solve afore-mentioned problems. ③ increases fight brace up damp. In cutting process, oscillatory generation energy hands point of a knife through stage of slideway, knife, once have oscillatory tendency, the other and oscillatory energy of the machine tool can transfer oscillatory system quickly, change into harmful oscillatory energy, cause serious low frequency brace up knife, pass a test the absorption with high-powered damping can effective space block is oscillatory energy, in the meantime, still can get very good surface surface roughness. Graph the chooses ④ knife handle option of 2 knife handle. Because balance the existence of iron, need reachs arbor knife desk 50 ～ 80mm. Machine working procedure hard to heavy cut, the knife handle with choice good tigidity can offer enough stability, balance to cutting flows and prolong cutting tool life, this is meant outside tall cutting parameter can be used when round turning. Press type through going up (rigid clamp) , lever type mixes wedge piece type means of 3 kinds of clamp (see a picture 2) use effect discovery: As a result of the influence of heat in metal cutting, the cylinder of wedge piece type sells be heated generation to be out of shape make bit and knife mat cannot be stuck very well close. Same, the clamp moment of force of lever type is controlled not easily, perhaps pass greatly too small also can bring about bit and knife mat to cannot be stuck well close, means of these two kinds of clamp produces collapse blade easily when high speed feed. Muscularity of clamp of type knife handle, clamp is pressed on reliable and big load of fixed position area is dispersive impact resistance is strong, because type knife handle is pressed on this,be the first selection of working procedure of heavy cut treatment. The high speed that we have epilogue does type cutting to experimented to pass batch to examine on many product line, its journal dimension, surface roughness and jumpy quantity all accord with craft to ask, and the logical choice of machine tool and cutting tool reached higher sexual price compare. Move actually to also prove, do type cutting technology through high speed is being used in working procedure of main shaft of crankshaft fine vehicle, the yield of crankshaft of my company forged steel can by 7 original.

5 / H promotion is 10.

6 / H, came true to produce the purpose of promotion, can managing cost. CNC Milling