CNC machines the category that still belongs to metallic cutting, but the characteristic that has its oneself. Basically the successive treatment course that runs automation, for long as a kind of height realizes this, among them tool setting time is more complex than conventional treatment, more time-consuming. Choosing a tool so from time to tome a lot of problems deserve a consideration. The article introduces the relevant knowledge of CNC commonly used cutting tool. I think good tool is the first condition that improves CNC to machine efficiency.
Tool vibration
The use as difficult treatment material is increasing, vibration already became the obstacle that improves treatment efficiency. Oscillatory happening affects treatment precision and exterior surface roughness directly, quicken cutting tool to wear away, affect cutting tool life badly, serious when cannot continue cutting treatment.
Tool vibration needs 3 conditions to exist at the same time. The machining complex that includes a tool inside is not quite solid, bring about natural frequency low. Can arise in cut process enough exterior stimulate brace up force. Exterior stimulate brace up the natural frequency of the frequency of force and process system is same. Syntonic.
The cent of train of thought that settles cutting tool vibration is 3 parts. It is the smallest above all turn cutting power. Make exhaust circular arc of may small point of a knife will reduce cutting force. Increase cutting tool before horn. Change with the bit that has worried the bit that has pressed. Reduce cut deep, raise rate, increase feed. Use 90 degrees to enter horn to long and thin axis. The milling machine of thin to containing staff, circular razor blade most conduce to reduce vibration.
2 it is the static stiffness that utmost land increases tool system or clamping apparatus and work.
3 it is in arbor interior produces alone vibration, the oscillatory frequency of incentive cutting force outside disturbing, eliminate cutting tool vibration thereby.
Bit wears away
In machining a process, face of the knife after knife face is mixed before often wears away very quickly. Among them, according to blade attaint circumstance needs to adopt all sorts of answering measure.
Face of the knife after 1. has worn away to cause the appearance greatly coarse, treatment dimension is poor
The reason of this kind of circumstance includes tall cut speed or small bit wearability. The solution includes to improve the method that decelerates cutting, increase cutting to measure gradually, use more the bit material of wear-resisting or coating, and use suitable mill and not be to go against mill.
2. breach wears away
May damage after the groove cut of bit and cause the appearance coarse and drossy. The reason includes feed rate too low. Milling machine is incidental treatment is sclerotic. Workpiece surface has oxidation skin. Face this kind of situation, answer to inspect the wear out condition of bit groove via commonly used nail.
3.The tumour accumulating bits when milling stainless steel and heat-resisting alloy
Of milling machine stick a knife to make accumulate bits tumour again, treatment surface is rough, occurrence burr. Because accumulate the desquamation of bits tumour, of cutting blade before knife face falls off, cutting blade is crushed, the 2 collapse blade of heat-resisting alloy workpiece brings about cutting blade to be crushed quickly. The reason no more than that creates this kind of situation is cutting blade blunt, before horn is speed of negative, cutting the low, ply that cut bits bits of too thin, platoon is undesirable etc.
Solve the method that accumulates tumor to be based on roughly " 6 measure " . The first pace is the cutting rate that raises stainless steel and aluminium alloy. The 2nd pace is use physics coating or not the razor blade of coating. The 3rd pace is to increase cutting to measure gradually, in order to achieve the optimal ply that cut bits. The 4th pace prepares enough high-pressured cooling fluid or air to cut bits in order to prevent 2 times. The 5th pace is to use suitable mill to replace go against mill. The 6th pace, clean the cutting region of heat-resisting titanium alloy and precipitation sclerosis stainless steel with low speed of pure mineral oil.
4. razor blade breaks off or bump into a knife
The reason that this kind of brim bursts apart has a lot of. If bit data is too hard, bit outline is too weak, or cut rate is too slow, cut brim may cave in, bring about cut inhomogenous or intermittent.
Considering this kind of circumstance, check spacer to whether damage above all or whether is the screw on bit out of shape need changes. 2 it is to should eliminate oscillatory coefficient, choose harder bit data, change the razor blade with stronger point. Finally, must raise cutting rate in order to eliminate cutting blade.