Raise stamping workpiece to produce quality

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Line of the products of car stamping workpiece rich, form is complex, when punch is produced, classics regular meeting produces a few undesirable phenomena, how to avoid the generation of the problem, oneself of union of heavy car of short for Shaanxi Province is actual, made beneficial exploration. The key that intermediate mask bracket is assembly of dial of appearance of type of car cab whole bearings join, it is to ensure the car is all sorts of appearance stability, reliable a when use important part. Because, the high speed of high-power engine rotates with car travel of road condition abominable, cause puissant vibration and jolt easily to cab, pan Zhongyi is controlled to express circuit and partial function open circuit or malfunction before be being caused thereby. Accordingly, intermediate mask bracket must can bear the action such as load of concussion, bend fatigue and torque, ask its must have enough bending strength, shear strength and better tenacity so. In addition, if should be made exceed when figuration allowable stress, or micro-crack expands certain level, cause thereby tear off or askew, can waste material not only so, and still can let a mould be in slant carry operation, quicken mould ageing. My factory in car cab assembly of appearance dial bracket is produced in, after discovering punch is produced, mask is left among its / right bracket often appears tear off, askew phenomenon, these blemish basically distributing making a pass place, sidewall turning point and R circular arc and mural neck boundary. After passing anatomize, we think its are main the reason is expect in moving process middling pressure by the mould core figuration is oriented not stable, sunken model and after pressing makings core clearance to wear away for a long time, cannot adjust and mould structure design is undeserved cause. Then, can from technology and management two respects offer relevant control measure, provide reference for design of craft of congener spare parts, mould and form cutting. Technological process of mask bracket punch is among common avulsion, askew form: Fall makings punching - punching cut - flange figuration - cut - flange. Happen in process of figuration of intermediate mask bracket tear off, askew form is varied, its tear off place to basically distributing making a pass part, sidewall corner is in R circular arc and mural neck boundary to wait, because of strike out form and the difference that produce craft condition, each rupture the proportion that place place holds is different. Tearing off can be one-time figuration is torn off, as a result of,also can be fatigue crackle namely invisible the avulsion that crackle development causes (graph 1) . Graph basis of case study of bracket of 1 intermediate mask the actual condition of the spot, make through the examination tear off configuration of place, fracture surface and crowded injury rate, think to cause make tear off, askew behavior basically is reflected in flange figuration working procedure, the cause that causes phenomenon of this working procedure to happen is as follows: 1.

This mould is flaw of design of flange figuration mould one model twin-circuit is left / right public, outside dividing flange as a result of this working procedure content, still have both form figuration content, together with is made special and complex, curved curved surface is narrow, core of makings of figuration requirement sunken mould pressing and figuration face conform to, bring about journey of figuration of mould structure condition big, control makings area small. When personnel is being designed in original mould, considered only pressure makings area is small this one feature, ignored however press makings core figuration to guide slippery journey (graph 2) . Graph 2 moulds side-glance guides slippery local presence designs blemish as follows: (1) press makings core to direct length design is 125mm, actual oriented length is 115mm, although be inside design limits, but existence holds partial 115mm motion in the palm to exceed effective oriented long 10mm, core of existence pressing makings is held in the palm not stable, make a malady that fixed position forbids. (2) be as long as the figuration height of 115mm, need to design special guide slide, cannot rely on to machine face and sunken model sidewall to slip match clearance to direct, skew sends attrition force to increase, self-lubricating effect extreme difference, powerful side force is couldn't get eliminate effectively, because wear away for a long time,the meeting after batch is produced is brought about and cause oriented clearance to increase, lose a mould to direct normally ahead of schedule the effect, can produce malign quality accident thereby. 2.

Mould treatment is made if the graph is shown 3 times,design existence error with blueprint, this place gives oriented area to line out is made clear to need to machine in blueprint. But because press makings core to be complex model machine treatment has to spigot surface again after face reason uses cast take shape, cause treatment face and sunken model spigot surface to slip error of clearance of the existence after matching, move normally in the mould appeared to press makings core in the process left / right swing. Graph plane of 3 lower mould is local before making a take shape, the fixed position that fixed position relies on to press the plane on makings core is sold reach Kong Jin to go, in expecting with respect to requirement pressing core is making a take shape so, must assure stable, reliable guide with correct ground slippery, make otherwise will break in figuration firm, make press makings core and sunken model wall to produce collision extruding thereby, cause make a generation pull stress, when the intensity limit that exceeds material, cause make tear off, askew and frame-up. Again together with, if the mould writtens guarantee other factor considers in compose, and negligence is used special the circumstance that guides slide directs, existence is both make after extruding attrition undertakes strongly, what oriented clearance instant is destroyed and cannot direct correctly is dangerous. Because the oriented clearance of this kind of structure slips to debug,compound gap, once attaint will do not have more effective ground to adjust a method, can long-term effect is made figuration quality, bring safe hidden trouble. And, did not use in oriented place special guide slide, used treatment face to direct each other instead structure, after existence gap is too big, the blemish that cannot adjust, brought about make appeared to tear off, askew and fraudulent action. 3.

Craft parameter does not carry out figuration to reach the designated position in controlling a figuration process, craft demand sunken model, pressure makings core and make bothly must close together joint is together, oppressive when machine tool slide block glides board makings plasticity is out of shape and realize figuration. But make an existence quality do not wait for defect firmly surely as a result of what suppress goes out now, pressure is in in explaining machine tool pressure is producing a course jumpy disequilibrium condition. Investigate its reason, basically be processing technique personnel did not appoint a requirement to be opposite in time in this one phase by craft machine tool pressure undertakes adjustment, perhaps be in of every order when having sex, did not communicate message of stability of machine tool pressure each other, and bring about make a quality be not stabilized. Because control measure is torn off in process of strike out form, askew reason is very much, and interconnection of photograph of a lot of reasons is. Accordingly, sheet perhaps runs a side from technical public relations cannot solve these problems thoroughly, must try to consider from mould craft and administrative field, the each link ability in solving good production obtains good result. 1.

Ensure mould structure rationality (1) graph 4 with the graph 5 install for lower mould respectively special guide before slide / hind the structure is comparative. Pass comparative analysis, can see: The machine addition form of point of will sunken before model directs the structure is perfected special self-lubricating after guide plate structure, can resist effectively side force, overcome the instability in controlling a figuration process, the freedom in can producing a course adjusts his reasonable clearance, make press makings core and sunken model guide plate to direct the clearance in moving holds long-term and even reasonable position thereby. This not only can make the mould moves more stable, and the service life that still can improve a mould greatly. Graph installation of 4 lower mould is special guide the structure before slide pursues installation of 5 lower mould is special guide the structure after slide (2) show 6 times like the graph, increase a mould to close high 70mm. It is in the mould in figuration process, after pressing makings core to be held in the palm, lower part significant oriented position adds to 80mm from 10mm, can add pressurization to expect core guides the interface between slide and guide plate of sunken model sidewall is accumulated so, in making mould pressing expects core is moving thereby, won't get the influence of figuration force, also guide steadily at the same time sunken model antrum, assure to make a fixed position reliable, ensure flange clearance is changed equably. Graph 6 moulds are local advocate view 2.

Pursue standardization operation, raise craft to control ability to go up from administrative point of view, want system of strict and normative craft, control the consistency of craft parameter and accuracy, parameter of the machine tool in making produce accords with the requirement of each parameter in craft from beginning to end, in the meantime, also should make sure machine tool pressure keeps for a long time in producing a course stable and reliable, comb-out presses difference, prevent pressure to cross accident of the quality since introductory note. Operation personnel should be operated meticulously, avoid to locate lever of not accurate, gas cap installs existence height difference and mould not to maintain reach the designated position wait for undesirable phenomenon to appear, lest create take shape load of material bend fatigue increases, make make fatigue maximum position is in in figuration instant, bring about problem happening. Epilogue is heavy-duty mask is left among spare parts of car cab assembly / right bracket, aborning appears tear off, askew behaviour is caused by a variety of element interaction, its attaint form is varied also. In the light of its only system of flange figuration process and attaint form take corresponding step, ability controls his effectively of many place tear off, concealed is cracked and wait for bad situation askew, raise the normal operation rate of the mould thereby, and the percent of pass of the spare parts and service life. CNC Milling CNC Machining