A very important facet in high speed processing technique is high speed takes silk thread cut. Because it has rate the advantage such as fast, cycle weak point, because this received general application in mould treatment industry. Machining the problem of fracture of wire that appears in the process, wasted a large number of time not only, still destroyed the integrality that machines the surface. How to solve this problem effectively, it is the key that mould treatment company cares. The rate of electrode silk motion that high speed takes silk thread cut is rapid, it can raise treatment substantially to manufacture efficiency, shorten work time. But high speed walks along silk thread cut to also existing a very serious problem -- fracture of wire. If be in cut workpiece process for many times fracture of wire, can cause certain pecuniary loss not only, and can bring the troublesome; that burns silk afresh not only lose time, and trace of fracture of wire can produce on workpiece, the influence machines quality, serious meeting causes workpiece to discard as useless. So how does ability solve high speed effectively to take the issue of fracture of wire of machine of silk thread cut? Analyse the cause that causes high speed to take fracture of wire of silk thread cut above all. Molybdenum silk one, on the molybdenum silk choice in molybdenum silk, the degree of finish of molybdenum silk diameter is a when affect fracture of wire main reason. Molybdenum silk is thick, can increase the pulling force of molybdenum silk on one hand, reduce molybdenum silk shake, on the other hand as a result of thick molybdenum silk broaden cut seam, working fluid is permeated easily go in, be helpful for discharging bits. What machine to ensure accordingly is stable, should change in time loss arrives the molybdenum silk of due process, because molybdenum silk attenuate becomes fragile,avoid fracture of wire and interrupt treatment. On the installation of molybdenum silk, the too loose too close easy fracture of wire of installation: If molybdenum silk installation is too loose, criterion molybdenum silk shakes fierce, can cause fracture of wire not only, and as a result of molybdenum silk shake surface roughness of surface of immediate impact workpiece. But molybdenum silk also cannot be installed too closely, too close internal stress increases, also can cause fracture of wire. On the choice of the athletic speed of molybdenum silk, rate walking along silk perhaps passes high too low cause fracture of wire easily. Speed walking along silk is exorbitant, electrode silk shakes serious, destroyed the stability of treatment, this makes machine speed to drop not only, and treatment precision and exterior surface roughness can become poor, cause fracture of wire easily. But speed walking along silk also cannot pass low, because loss is big,add man-hour otherwise, easy also fracture of wire, because this is general experience in order to be less than 10m/s advisable. In molybdenum silk store on, molybdenum silk has 3 to be afraid of: Be afraid of tide, be afraid of fold and be afraid of bask in. Be affected with damp be affected with damp can oxidize, fold and break easily, bask in and become fragile, new purchased molybdenum silk should be put in the appropriate in sealed appliance to save, along with with along with take. 2, the carry silk orgnaization of machine of cut of line of orgnaization sending silk (also call seal wire the orgnaization) basically be by lay aside silk canister, line is worn and guide pulley is comprised. There is blemish in because canister of lay aside silk, line wearing and guide pulley are in,machining a process, cause fracture of wire easily necessarily. The radial and jumpy meeting of canister of lay aside silk makes the tension of electrode silk is reduced, cause a pine, serious when can make molybdenum silk is pulled from the emergence in guide pulley chamfer. The axial change of canister of lay aside silk is moved can make discharge silk not divide evenly, generation folds filar phenomenon. Circle of inside and outside of canister of lay aside silk is not coaxial, can produce lopsided inertia, easy generation folds silk when movement and bring about fracture of wire. The spare parts such as the axis of canister of lay aside silk and bearing often produces gap because of wearing away, cause silk easily also to shake and fracture of wire, when inverting of canister of lay aside silk if did not cut off high frequency power source, can bring about molybdenum silk to be in temperature of short time internal cause is exorbitant and generation burns silk; Roll of canister of lay aside silk, guide pulley is not agile, vibration of seal wire system can be caused when movement going there and back and fracture of wire; The spacing link stopper of back end of canister of lay aside silk was not adjusted good, canister of lay aside silk develops spacing stroke and cause fracture of wire; Stop immediately after inverting machine, because canister of lay aside silk is inertial exceed Cheng to be reached to bad transmission engine pull molybdenum silk. Additional, chamfer of form of guide pulley V broadens, the bottom diameter out of round of chamfer of form of guide pulley V and electric axis and electric round of contact is bad to also can cause fracture of wire. 3, workpiece to forginging function, temper by dipping in water appears a gender bad, heat is out of shape old workpiece stuff, if do not undertake forge is hit is opposite, quench a temper handle and undertake high speed takes silk thread cut directly, workpiece of the presumable in machining a process is met craze, touch molybdenum silk; Some meetings make clearance is out of shape, place molybdenum silk or play. Additional, workpiece material is qualitative impure, internal stress is greater, hold clip with workpiece bad, cause fracture of wire extremely likely. 4, fluid of working fluid job blackens, night of the job in perhaps be being machined is too thick, too dirty cause fracture of wire very easily (special when cutting especially deep work) . 5, parameter of electric parameter report is chosen undeserved also be a when cause fracture of wire main reason, want to choose reasonable electric parameter according to workpiece ply so, pull open pulse interval a few, be helpful for the eduction of fused metal particle, at the same time peak value electric current and sky carry voltage to should not be exorbitant, make individual pulse energy greatens otherwise, cut speed is accelerated, easy generation discharges centrally and pull arc, cause fracture of wire. Choose suitable discharge space according to workpiece ply, discharge clearance cannot too small, produce short circuit easily otherwise, also go against refrigeration and electric corrode content eliminate. Discharge gap is too big, influence surface surface roughness and treatment speed. 6, electric current of treatment of pulse power source is very big, scintilla discharge is unusual, right now the output of pulse power source already turned into to shed output continuously. If output electric current to be restricted to be worth more than, discharge of the scintilla in machining a process turns into suddenly blue arc discharge. Burn dot appears on molybdenum silk, it makes discharge is centered on molybdenum silk, calorific amount is large. 7, the cut precision of workbench shift work relies on guide screw to assure, the clearance of guide screw and nut is to rely on bedspring to eliminate. If filar lever is lubricant undesirable or bedspring power is insufficient, can cause workbench crawl to move. Cut finishs in this kind of circumstance, high frequency electric current can appear frequent short circuit, if remove trouble not in time, certainly will causes fracture of wire. 8, factitious element question of this part novice is more, if silk did not put guide pulley, the silk on filar bucket edge was not pressed good, when cutting great work there is not of grip ┉ ┉ finally to the problem of fracture of wire that often appears, introduce the means of settlement of a few effective simply, following: In molybdenum silk anthology go up, take treatment of silk thread cut to high speed, use extensively 0.
06 ～ 0.
The molybdenum silk of 25mm, commonly used in 0.
12 ～ 0.
Between 18mm. If need to obtain fine figure and very small round horn radius when, choose 0.
The electrode silk of 04mm, because it is able to bear or endure loss, tensile strength tall, silk becomes not easily fragile character and less fracture of wire. The pulling force that increases electrode silk additionally can reduce silk brace up influence, raise precision and cut rate thereby. (think tension is in commonly 12-15N is more appropriate, rate walking along silk is average in order to be less than 10m/s advisable) . When using new molybdenum silk, treatment electric current needs to be reduced appropriately, after waiting for electrode silk to become white basically, can return to normal electric parameter. When installing molybdenum silk, molybdenum silk should be circled on canister of lay aside silk by formulary trend, secure two end at the same time. When circling silk, two end leave canister of general store silk each 10mm, circle among do not overlap completely, the in part that tube length of not less than lay aside silk spend width, lest electric machinery inverting is frequent and make parts quickens attaint, also prevent molybdenum silk shares cut often and fracture of wire. Circle on after molybdenum silk, adjust the device that block silk. Go up, next device that block silk are effective, 1 what make span of silk of molybdenum of the both sides on canister of lay aside silk sells a diameter to block silk.
5 times (make an appointment with 8mm) . More or less to adjust the position of inverting link stopper according to circling silk, general the molybdenum silk that two end leave 2-3mm each does not attend cut, fracture of wire produces in order to avoid when inverting. However, the processing technique of the fracture of wire that not electric to containing in workpiece material causes is: Work out a paragraph every are entered 0.
05-0.
1mm backs down 0.
The program of 5-1mm, use repeatedly in treatment, increase cooling fluid flow, can erode commonly foreign matter, return to normal cut. Additional, when choosing workpiece material, should choose to forging as far as possible good, temper by dipping in water shows performance quality good, heat treatment is out of shape little material, the place in making rolled steel contains carbide to distributing even, make machine stability to increase thereby. But to those forginging function, temper by dipping in water appears a gender bad, heat is out of shape old workpiece stuff, before undertaking high speed takes silk thread cut, must use microtherm temper to eliminate internal stress, because if the internal stress of workpiece is done not have,get elimination, when cut, some workpiece can split, touch molybdenum silk. If of treatment is massiness workpiece, can be about to end in treatment when, with magnet grip will finish falling work, perhaps protect the work of whereabouts artificially, make its parallel and slow whereabouts prevents fracture of wire thereby. The electric parameter with the ply right choice that processes work in the basis in machining a process also can very good prevent fracture of wire. It is when the work with cut greater ply, answer to choose wide electric current of big arteries and veins as far as possible, at the same time discharge clearance also wants a bit bigger (should be more than commonly 0.
02mm) , enhance the result that discharge bits thereby, increase the stability of cut. Also be to have cultured very much on the choice of power source of high frequency pulse, short-circuit current peak value cannot pass big, negative wave of high frequency pulse cannot pass big, leakage current of canal of power of output of pulse power source cannot pass big, these electric current must be chosen strictly according to the diameter of molybdenum silk. Still must choose appropriate pulse width and pulse interval at the same time. Finally is should notice on the use of working fluid: Workpiece of tall to demand cut speed or big ply, of its job fluid deserve to compare but proper a few weaker, make an appointment with the chroma of 5%-8% , such treatment are stabler, not easy fracture of wire. What and want assure working fluid is clean. The analysis that above is reasons of pair of fracture of wire and a few means of settlements, notice observation in be operated actually only, sum up experience ceaselessly, the avoids appearance of fracture of wire happening of ability utmost, shorten handling time, enhance company competition ability. CNC Milling