外文翻譯--普通全鋼沖模的沖壓精度分析

1、<p><b>　　附錄A</b></p><p>　　普通全鋼沖模的沖壓精度分析</p><p>　　板料沖壓件的精度準確顯示出其沖模的沖壓精度。而任何沖件的線性尺寸精度與形位精度主要取決于沖模沖裁和立體成形沖壓件展開平毛坯的落料精度。因此，多工步復合沖壓的單工位復合模、多工位連續(xù)模的沖壓精度，在普通沖壓的眾多種類與不同結構的沖模中，最具典型性和代表性。

2、沖模的沖壓精度分析  對沖模投產(chǎn)至失效報廢各個時期沖件的實際誤差分析，可以看出其增大的時期及趨向，從而分析其增大的因素。新沖模投產(chǎn)至第一次刃磨前沖制沖件的誤差即所謂的初始誤差；沖模經(jīng)過20次左右刃磨至失效報廢前沖制的沖件誤差稱之為常規(guī)誤差；而沖模失效報廢前沖制的最后一批合格沖件的允許最大誤差稱之為極限誤差。在現(xiàn)場，確定沖模刃磨壽命的依據(jù)是沖件沖孔與落料的毛刺高度。由于任何成形件都具有沖裁作業(yè)（毛坯落料或沖孔），對于復合

3、模尤為如此。所以，沖件毛刺高度的觸模檢查和測量并按企業(yè)標準或JB4129-85《沖壓件毛刺高度》對照檢測就顯得十分重要。  沖模的初始誤差通常是沖模整個壽命中沖件誤差最小的。其大小主要取決于沖模的制造精度與質(zhì)量及沖件尺寸、料厚以及間隙值大小與均勻度。沖模的制造精度及質(zhì)量又取決于制模工藝。對于料厚t≤1mm</p><p>　　（2）沖壓工藝及沖模結構類型  采用不同的沖壓工藝，

4、沖件的精度及固定誤差相差甚大。除上述片齒輪實例說明，精沖工藝與普通沖裁的沖件精度與固定誤差相差一個數(shù)量級之外，即便在普通沖裁中，采用不同間隙沖裁，固定誤差相差也很大。例如料厚t=1.5mm的H62黃銅沖裁件，選用C≤40%t單邊Ⅰ類小間隙沖裁比選用C≤8%t（單邊）Ⅲ類大間隙沖裁，沖件固定誤差將加大40%～60%，精度至少降一級。此外，采有無搭邊排樣，沖件的誤差要遠大于有搭邊排樣沖件。無搭邊排樣沖件。無搭邊排樣沖件的精度低于IT12級，

5、而多數(shù)有搭邊排樣的沖件精度在IT11～IT9級之間，料厚t＞4mm的沖件，尺寸精度會更低一些。不同沖模結構類型，由于適用沖壓料厚及制造精度的差異，導致沖件的固定誤差有別。復合模中，多工位連續(xù)式復合模由于沖件連續(xù)重復定位加上制模誤差較大，故其沖件的固定誤差比單工位復合沖裁模要 大1～2級。  （3）沖模制造工藝  沖模主要工作零件即凸、凹模的加工程序，對操作上的技術要求不高，能夠一次成形較復雜的模腔。但其

6、加工表面約厚＞0.03～0.05mm為高溫燒蝕的殘余樹枝狀奧氏體組織，硬度可高達</p><p><b>　　附錄B</b></p><p>　　General all-steel punching die’s punching accuracy</p><p>　　Accuracy of panel punching part is disp

7、lay the press accuracy of the die exactly. But the accuracy of any punching parts’ linear dimension and positional accuracy almost depend on the blanking and blanking accuracy ,. So that the compound mould of compound pu

8、nching’s accuracy, is typicalness and representation in the majority.</p><p>　　Analyse of the die’s accuracy </p><p>　　For the analyse of pracyicable inaccuracy during production of dies to inac

9、tivation, we could get the tendency when it is augmentation in most time. From this we could analyse the elements . when the new punch dies pt into production to the first cutter grinding, the inaccuracy produced called

10、initial error ; if the die grinding more than twenty times , until it’s discard, the inaccuracy called conventional error ; and before the dies discard, the largest error of the last batch permit , called </p><

11、;p>　　The initial error usually is the minimal through the whole life of die. Its magnitude depend on the accuracy of manufacture, quality, measure of the punching part, thickness of panel, magnitude of gap and degree

12、of homogeneity. The accuracy of manufacture depend on the manufacture process. For the 1 mm thicked compound punching part made in medium steel, the experimental result and productive practice all prove that the burr of

13、 dies which produced by spark cutting are higher 25%~~30% than produ</p><p>　　The normal error of the punch die is the practicable error when the fist cutter grinding and the last cutter grinding before the

14、die produce the last qualified product. As the increase of cutter grinding, caused the measure the nature wear of the dies are gradual increasing, the error of punching part increase also, so the parts are blew proof. An

15、d the die will be unused. The hole on the part and inner because the measure of wear will be small and small gradually, and its outside form will be la</p><p>　　The limit error in punching parts are the max

16、dimension error which practicable allowed in the parts with limit error. This kind of parts usually are the last qualified products before the die discard.</p><p>　　For the all classes of dies, if we analyse

17、 the fluctuate, tendency of increase and decrease and law which appeared in the die’s whole life, we will find that the master of the error are changeless; the error that because the abrade of the cutter and impression w

18、ill be as the cutter grinding times increased at the same time. And that will cause the error oversize gradually; and also have another part error are unconventional , unforeseen. Therefore, every die’ s error are compos

19、ed of fixed error,</p><p>　　1. fixed error </p><p>　　At the whole process when the New punching die between just input production to discard, the changeless master error that in qualified part a

20、re called fixed error. It’s magnitude is the deviation when the die production qualified products before the first cutter grinding. Also is the initial error, but the die have initial punching accuracy at this time. Beca

21、use of the abrade of parts, the die after grinding will be change the dimension error. And the increment of deviation will oversize as the</p><p>　　the material , sorts, structure, (form) dimension, and thi

22、ck of panel</p><p>　　the magnitude of punching gap and degree of homogeneity are have a important effect for the dimension accuracy. Different punching process, material, thick of panel, have completely diff

23、erent gap and punching accuracy. A gear H62 which made in yellow brass with the same mode number m=0.34, 2mm thick and had a center hole, when the gap get C=0.5%t (single edge) , and punched with compound punching die, a

24、nd the dimension accuracy reached IT7, the part have a flat surface ,the verticality of tangen</p><p>　　punching craft and molder structure type</p><p>　　Uses the different ramming craft, flushe

25、s a precision and the fixederror difference is really big. Except that the above piece gearexample showed, the essence flushes the craft and ordinary punching flushes a precision and the fixed error differs outside a mag

26、nitude,even if in ordinary punching center, uses the different gap punching, thefixed error difference very is also big. For example material thickt=1.5mm H62 brass punching, selects C <= the 40%t unilateral I kind of

27、small gap punching comp</p><p>　　the craft of punching die’s manufacture</p><p>　　the main work of punching die namely are raised, the concave moldprocessing procedure, to operates on the specif

28、ication not to behigh, can time form a more complex cavity. But its processing surfaceapproximately is thick > 0.03 ~ 0.05mm is the high temperatureablation remaining furcated austenite organization, degree ofhardness

29、 may reach as high as HRC67 ~ 70, has the micro crack, easilywhen punching appears broke the cutter or flaking. The Italian CorradaCorporation's related memoir called "the</p><p>　　With precisely ru

30、bs truncates the law manufacture punching die, specially makes the high accuracy, the high life punching die, such as: Thin material small gap compound punching die, multi- locations continuous type compound die and so o

31、n, has the size precision high, the work component smachined surface roughness Ra value is small, the mold life higher characteristic. Its processing craft at present changed the electrical fire by the past ordinary engi

32、ne bed rough machining spark cutting or the</p><p>　　gap size and degree of homogeneity </p><p>　　the flange and other sheet forming sgene rally all must first punching (fall material) the plate

33、 to launch the semi finished materials, after also has the forming to fall the material, the incision obtains the single end product to flush. Therefore punching the work, including is commonly used punching hole, the ma

34、rgin, cut side and so on, regarding each kind of sheet pressing partall is necessary. Therefore punching the gap to flushes a out form in chprecision to have the decisive influence. pu</p><p>　　ramming equip

35、ment elastic deformation In the ramming process </p><p>　　after the punch press load bearing can have the certain elastic deformation. Although this kind of distortion quantity according to flushes the press

36、ure the size to change also tohave the obvious directivity, but on the pressing part, mainly is tohas the volume ramming archery target stamping, embosses, thee qualization, the pressure is raised, the wave, flushes crow