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河南機(jī)電高等?？茖W(xué)校 學(xué)生畢業(yè)設(shè)計(jì)中期檢查表 學(xué)生姓名 劉 笛 學(xué) 號(hào) 051304233 指導(dǎo)教師 蘇 光 課題名稱 軸碗沖壓工藝及落料拉深沖孔翻孔復(fù)合模的設(shè)計(jì) 難易程度 偏難 適中 偏易選題情況 工作量 較大 合理 較小 任務(wù)書 有 無 開題報(bào)告 有 無符合規(guī)范化 的要求 外文翻譯質(zhì)量 優(yōu) 良 中 差 學(xué)習(xí)態(tài)度 出勤情況 好 一般 差 工作進(jìn)度 快 按計(jì)劃進(jìn)行 慢 中期工作匯 報(bào)及解答問 題情況 優(yōu) 良 中 差 中期成績(jī)?cè)u(píng)定 所在專業(yè)意見 負(fù)責(zé)人 年 月 日 河南機(jī)電高等?？茖W(xué)校 畢業(yè)設(shè)計(jì)任務(wù)書 系 部 材料工程系 專 業(yè) 模具設(shè)計(jì)與制造 學(xué) 生 姓 名 劉 笛 學(xué) 號(hào) 051304233 設(shè)計(jì)題目 軸碗的沖壓工藝及模具設(shè)計(jì) 起 迄 日 期 2008 年 3 月 20 日 6 月 8 日 指 導(dǎo) 教 師 蘇 光 發(fā)任務(wù)書日期 08 年 3 月 20 日 畢 業(yè) 設(shè) 計(jì)任 務(wù) 書 1 本畢業(yè)設(shè)計(jì)課題來源及應(yīng)達(dá)到的目的 工件名稱 軸碗 生產(chǎn)批量 大批量 材料 20 鋼 厚度 t 1 5mm 工件簡(jiǎn)圖 如圖所示 2 本畢業(yè)設(shè)計(jì)課題任務(wù)的內(nèi)容和要求 包括原始數(shù)據(jù) 技術(shù)要求 工作要 求等 1 了解目前國內(nèi)外沖壓模具的發(fā)展現(xiàn)狀 2 分析軸碗零件的沖壓工藝并確定其工藝方案 3 軸碗零件的落料拉深沖孔翻孔復(fù)合模設(shè)計(jì) 4 繪制模具總裝圖 并繪制零件圖 5 軸碗零件的模具安裝與調(diào)整 6 得出設(shè)計(jì)結(jié)論 所在專業(yè)審查意見 負(fù)責(zé)人 年 月 日 系部意見 系領(lǐng)導(dǎo) 年 月 日 機(jī)械加工工藝過程卡 產(chǎn)品型號(hào) 零 部 件 圖號(hào) 03機(jī)械加工工 藝過程卡片 產(chǎn)品名稱 凸 模 零 部 件 名稱 凸模 共 1 第 1 頁 材料牌號(hào) C r 1 2 M o V 毛 坯 種 類 圓 棒 料 毛坯 外型 尺寸 65 每個(gè)毛坯可 制件數(shù) 4 每臺(tái)件數(shù) 4 備注 工時(shí) 工序 號(hào) 工序名 稱 工序內(nèi)容 車間 工 段 設(shè) 備 工 藝 裝 備 準(zhǔn) 終 單 件 05 下料 鋸割下料 65 70 下料車間 鋸 床 0 5 10 鍛 鍛成 63 65 鍛造車間 空 氣 錘 2 15 熱處理 退火 熱處理車 間 熱 處 理 爐 10 20 車削 車外圓 63 達(dá)尺 寸要求 車退刀槽 2 2 車外圓 20 5 留磨量 0 5 掉頭車左端 留磨 量 0 2 模具車間 車 床 5 25 銑 銑右端面達(dá)圖紙要 求 30 熱處理 淬火并回火達(dá) 58 62HRC 熱處理車 間 12 35 磨外圓 和右端 面 磨外圓 62 5 和 20 5 達(dá)到要求 模具車間 2 40 鉗 研磨 19 15 達(dá)圖樣要求02 模具車間 2 標(biāo) 記 記數(shù) 更 改 文 件 號(hào) 簽字 日期 標(biāo)記 處數(shù) 更 該 文 件 號(hào) 設(shè) 計(jì) 日 期 審核 日期 標(biāo)準(zhǔn)化 日期 會(huì)簽 日期 結(jié)論 外文翻譯 專 業(yè) 名 稱 機(jī)械設(shè)計(jì)制造及其自動(dòng)化 班 級(jí) 學(xué) 號(hào) 078105232 學(xué) 生 姓 名 冼 振 源 指 導(dǎo) 教 師 陳 為 國 填 表 日 期 2011 年 1 月 17 日 General all steel punching die s punching accuracy Accuracy of panel punching part is display 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 punching s accuracy is typicalness and representation in the majority Analyse of the die s accuracy For the analyse of pracyicable inaccuracy during production of dies to inactivation 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 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 limiting error at job site the evidence to confirm life of sharpening is the higher of the blanking punched hole or punched parts Because all finished parts had been blanked so it is especially for the compound dies Therefore the analyse of burr and measurement is especially important when do them as enterprise standardization or checked with 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 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 dies which produced by spark cutting are higher 25 30 than produced by grinder NC or CNC The reason is that not only the latter have more exact machining accuracy but also the value of roughness Ra is less one order than the formmer it can be reached 0 025 m Therefore the die s initial blanked accuracy depends on the accuracy of manufacture quality and so on The normal error of the punch die is the practicable error when the fist cutter grinding and the last cutter grinding before the 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 And 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 lager in the same reason Therefore the hole and inner form in the part will be made mould according to one way positive deviation or nearly equal to the limit max measure In like manner the punching part s appearance will be made mould according to one way negative deviation or nearly equal to limit mini measure For this will be broaden the normal error and the cutter grinding times will be increased the life will be long The limit error in punching parts are the max 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 For the all classes of dies if we analyse 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 will 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 composed of fixed error system error accident error and so on 1 fixed error At the whole process when the New punching die between just input production to discard the changeless master error that in qualified part are 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 Because of the abrade of parts the die after grinding will be change the dimension error And the increment of deviation will oversize as the times of cutter grinding So the punching accuracy after cutter grinding also called grinding accuracy and lower tan initial accuracy The fixed error depend on the elements factor as followed 1 the material sorts structure form dimension and thick of panel 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 different 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 and the dimension accuracy reached IT7 the part have a flat surface the verticality of tangent plane reached 89 5 its roughness Ra magnitude are 12 5 m height of burr are 0 10mm and the punching part are punched with progressive die the gap C 7 t single edge initial accuracy are IT11 and have an more rough surface even can see the gap with eyes In the usual situation flushes a material and its thickness t is theselection punching gap main basis Once the designation gap haddetermined flushes the plane size the fixed error main body Flushesthe structure rigidity and the three dimensional shape affects itsshape position precision 2 punching craft and molder structure type Uses the different ramming craft flushes 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 magnitude 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 ofsmall gap punching compared to select C 4mm flushes the size precision can lower some Different die s structure type because is suitable the rammingmaterial to be thick and the manufacture precision difference causesto flush a fixed error to have leaves Compound die center multi locations continuous type compound die because flushes continuously toduplicate the localization to add on the pattern making error to bebigger therefore it flushes a fixed error compound punching die to wantcompared to the single location Big 1 2 levels 3 the craft of punching die s manufacture the main work of punching die namely are raised the concave moldprocessing procedure to operates on the specification 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 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 line cut the processing contruction to have the disadvantageous influence to the superficialgold in fact already changed the gold contruction We must use theJin gang stone powder to grind or the numerical control continual pathcoordinates rub truncate cut to line to make the precision work In recent years country and so on Switzerland and Japan has conductedthe thorough research to the electrical finishing equipment and abigger improvement makes function complete high accuracy NC and theCNC line cutter the processing precision may reach 0 005 0 001mm even is smaller The processing surface roughness Ra value can achieve0 4 mu m According to the recent years to the domestic 12 productionlines cutter factory investigation and study the domesticallyproduced line cutter processing precision different factory differentmodel line cutter might reach 0 008 0 005mm generally all in 0 01mm or bigger somewhat was individual also can achieve 0 005mm the processing surface roughness Ra value was bigger than1 6 m However the electrical finishing ablation metal surface thus the change and the damage machined surface mental structure character can not change only if with rubs truncates or other ways removes this harmful level Therefore merely uses electricity machining including the spark cutting and the electricity perforation achieves with difficulty punching especially high accuracy high life punching die to size precision and work components surface roughness Ra value request With precisely rubs 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 on 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 engine bed rough machining spark cutting or the electricity puncher rough machining finally precisely rubs truncates also from takes shape rubs optics curve rubs the manual grid reference rubs gradually filters the continual path grid reference to rub and NC and the CNC continual path grid reference rubs Processing coarseness may reach 0 001 0 0005mm the processing surface roughness Ra value may reach 0 1 0 025 mu m Therefore with this craft manufacture the die regardless of the size precision the work components surface roughness all can satisfy die each kind of compound request the die is especially higher than the electrical finishing craft manufacture scale 4 gap size and degree of homogeneity the flange and other sheet forming sgene rally all must first punching fall material the plate 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 margin 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 punching the gap small and is even may cause punching the size gain high accuracy Regarding drawability is curving and so on mould the gap greatly will decide increases flushes the oral area size error and the snapping back The gapnon uniformity can cause to flush a burr enlarges and incurs cutting edge the non uniform attrition 5 ramming equipment elastic deformation In the ramming process After the punch press load bearing can have the certain elastic deformation Although this kind of distortion quantity according to flushes the pressure the size to change also to have the obvious directivity but on the pressing part mainly is to has the volume ramming archery target stamping embosses the equalization the pressure is raised the wave flushes crowds the shape the flange hits flatly thinly changes draw ability and so on the craft work punching forming flushes has the significant influence to its ramming aspect size precision 普通全鋼沖模的沖壓精度分析 板料沖壓件的精度準(zhǔn)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(fù)合沖壓的單工位復(fù)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(jié)構(gòu)的沖模中 最具典型性和代表性 沖模的沖壓精度分析 對(duì)沖模投產(chǎn)至失效報(bào)廢各個(gè)時(shí)期沖件的實(shí)際誤差分析 可以看出其增大的時(shí)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(bào)廢前沖制的沖件誤差稱之 為常規(guī)誤差 而沖模失效報(bào)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(chǎng) 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(duì)于復(fù)合模尤為如此 所以 沖件毛刺高度的觸模檢查和測(cè)量并按企業(yè)標(biāo)準(zhǔn)或 JB4129 85 沖壓件毛 刺高度 對(duì)照檢測(cè)就顯得十分重要 沖模的初始誤差通常是沖模整個(gè)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(duì)于料厚 t 1mm 的中碳鋼復(fù)合沖裁模沖件 實(shí) 驗(yàn)結(jié)果與生產(chǎn)實(shí)踐都證明 電火花線切割制造的沖模沖件毛刺高度比用成型磨 或 NC 與 CNC 連續(xù)軌跡座標(biāo)磨即精密磨削工藝制造的沖模沖件要高 25 30 這是因?yàn)楹笳卟粌H加工精度高 而且加工面粗糙度 Ra 值要比前者小一個(gè)數(shù)量級(jí) 可達(dá)到 0 025 m 因此 沖模的制造精度與質(zhì)量等因素決定了沖模的初始沖壓 精度 也造就了沖件的初始誤差 沖件的常規(guī)誤差是沖模經(jīng)第一次刃磨到最后一次刃磨后沖出最后一個(gè)合格沖件 為止 沖件實(shí)際具有的誤差 隨著刃磨次數(shù)的增加 刃口的自然磨損而造成的 尺寸增量逐漸加大 沖件的誤差也隨之加大 當(dāng)其誤差超過極限偏差時(shí) 沖件 就不合格 沖模也就失效報(bào)廢 沖件上孔與內(nèi)形因凸模磨損尺寸會(huì)逐漸 變小 其外形落料尺寸會(huì)因凹模磨損而逐漸增大 所以 沖件上孔與內(nèi)形按單 向正偏差標(biāo)允差并依接近或幾乎等于極限最大尺寸制模 同理 沖件外形落料 按單向負(fù)偏差標(biāo)注允差并依接近或幾乎等于極限最小尺寸制模 這樣就使沖件 的常規(guī)誤差范圍擴(kuò)大 沖?？扇心ゴ螖?shù)增加 模具壽命提高 沖件的極限誤差是具有極限偏差的沖件所具有的實(shí)際允許的最大尺寸誤差 這 類沖件通常是在沖模失效報(bào)廢前沖制的最后一批合格沖件 對(duì)各類沖模沖件誤差在沖模整個(gè)壽命中出現(xiàn)的波動(dòng) 增減趨向及規(guī)律等進(jìn)行全 面分析便可發(fā)現(xiàn) 沖件誤差的主導(dǎo)部分是不變的 因刃口或型腔的自然磨損而 出現(xiàn)的誤差增量隨沖模刃磨沖數(shù)增加而使這部分誤差逐漸加大 還有部分誤差 的增量是非常規(guī)的 不可預(yù)見的 所以 各類沖模沖件誤差是由因定誤差 漸 增誤差 系統(tǒng)誤差及偶發(fā)誤差等幾部分綜合構(gòu)成 1 固定誤差 新沖模在指定的沖壓設(shè)備上投入使用至失效報(bào)廢的整個(gè) 總 壽命過程中 其 合格沖件誤差的主導(dǎo)部分固定不變即所謂固定誤差 其大小就是新沖模第一次 刃磨前沖制的合格沖件的偏差 也即沖模的初始誤差 而此時(shí)的沖模具有初始 沖壓精度 刃磨后的沖模 因其工作零件 凸 凹模 磨損而改變尺寸誤差 使沖件識(shí)差增量隨刃磨次數(shù)增加而逐漸加大 故沖模刃磨后的沖壓精度亦稱 刃磨精度 比其初始精度要低 沖模沖件的固定誤差取決于以下各要素 1 沖件的材料種類 結(jié)構(gòu) 形狀 尺寸及料厚 沖裁間隙的大小及其均勻度對(duì)沖裁件的尺寸精度有決定性的影響 不同沖裁工 藝 不同材料種類與不等料厚 間隙相差懸殊 沖壓精度差異很大 同一種模 數(shù) m 0 34 的 2mm 的料厚 中心有孔的 H62 黃銅材料片齒輪復(fù)合模沖件 當(dāng)取間 隙 C 0 5 t 單邊 用復(fù)合精沖模沖制 沖件尺寸精度達(dá)到 IT7 級(jí) 沖件平 直無拱彎 沖切面垂直度可達(dá) 89 5 其表面粗糙 Ra 值為 0 2 m 而用普通 復(fù)合模沖制 間隙 C 5 t 單邊 沖件初始誤差亦即沖模的初始沖壓精度為 1T9 級(jí) 沖切面粗糙度 Ra 值為 12 5 m 毛刺高度為 0 10mm 還是這個(gè)沖件用 連續(xù)模沖制 間隙 C 7 t 單邊 初始沖件精度為 IT11 級(jí) 沖切面更粗糙 甚至有肉眼可見的臺(tái)階 通常情況下 沖件材料及其厚度 t 是選取沖裁間隙的 主要依據(jù) 一旦選定間隙就確定了沖件的平面尺寸的固定誤差的主體 沖件結(jié) 構(gòu)剛度及立體形狀則影響其形位精度 2 沖壓工藝及沖模結(jié)構(gòu)類型 采用不同的沖壓工藝 沖件的精度及固定誤差相差甚大 除上述片齒輪實(shí)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(gè)數(shù)量級(jí)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 類小間隙沖裁比選用 C 8 t 單邊 類大間隙沖裁 沖件固定誤差將加大 40 60 精度至少降一級(jí) 此外 采有 無搭邊排樣 沖件的誤差要遠(yuǎn)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(jí) 而多數(shù)有搭邊排樣的沖件精度在 IT11 IT9 級(jí)之 間 料厚 t 4mm 的沖件 尺寸精度會(huì)更低一些 不同沖模結(jié)構(gòu)類型 由于適用沖壓料厚及制造精度的差異 導(dǎo)致沖件的固定誤 差有別 復(fù)合模中 多工位連續(xù)式復(fù)合模由于沖件連續(xù)重復(fù)定位加上制模誤差 較大 故其沖件的固定誤差比單工位復(fù)合沖裁模要 大 1 2 級(jí) 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(duì)操作上的技術(shù)要求不高 能夠一 次成形較復(fù)雜的模腔 但其加工表面約厚 0 03 0 05mm 為高溫?zé)g的殘余樹 枝狀?yuàn)W氏體組織 硬度可高達(dá) HRC67 70 有顯微裂紋 容易在沖裁時(shí)出現(xiàn)崩 刃或剝落 意大利 Corrada 公司的有關(guān)研究報(bào)告稱 線切割加工對(duì)表面金相結(jié) 構(gòu)產(chǎn)生不利的影響 實(shí)際上已經(jīng)改變了金相結(jié)構(gòu) 我們必須用金剛石粉研磨或 數(shù)控連續(xù)軌跡坐標(biāo)磨削 對(duì)線切割件 作精加工 近年來瑞士和日本等國 對(duì)電加工設(shè)備進(jìn)行了深入的研究和較大的改進(jìn) 制造出功能齊全的高精度 NC 和 CNC 線切割機(jī) 加工精度可達(dá) 0 005 0 001mm 甚至更小 加工表面粗糙 度 Ra 值能達(dá)到 0 4 m 根據(jù)近年對(duì)國內(nèi) 12 家生產(chǎn)線切割機(jī)工廠的調(diào)研 國產(chǎn) 線切割機(jī)加工精度各別廠家的各別型號(hào)線切割機(jī)可達(dá) 0 008 0 005mm 一 般都在 0 01mm 或更大一些 個(gè)別也能達(dá)到 0 005mm 加工表面粗糙度 Ra 值 均大于 1 6 m 然而 電加工燒蝕金屬表面從而改變和損壞加工面金相結(jié)構(gòu)的 特性不會(huì)改變 除非用磨削或其他加工法去除這一有害層 所以 僅僅用電加 工法 包括電火花線切割與電穿孔 難以達(dá)到?jīng)_模 尤其高精度 高壽命沖模 對(duì)尺寸精度與工作零件表面粗糙度 Ra 值要求 用精密磨削法制造沖模 特別是制造高精度 高壽命沖模 諸如 薄料小間隙 復(fù)合沖裁模 多工位連續(xù)式復(fù)合模等 具有尺寸精度高 工作零件加工面粗糙 度 Ra 值小 模具壽命高等特點(diǎn) 其加工工藝目前已由過去的普通機(jī)床粗加工改 為電火花線切割或電穿孔機(jī)粗加工 最后精密磨削 也由成型磨 光學(xué)曲線磨 手動(dòng)座標(biāo)磨逐步過濾到連續(xù)軌跡座標(biāo)磨及 NC 與 CNC 連續(xù)軌跡座標(biāo)磨 加工粗度 可達(dá) 0 001 0 0005mm 加工表面粗糙度 Ra 值可達(dá) 0 1 0 025 m 所以 用該工藝制造的沖模 無論尺寸精度 工作零件表面粗糙度 都能滿足沖模 尤其各種復(fù)合模的要求 比電加工工藝制造的沖模高一個(gè)檔次 4 間隙的大小與均勻度 拉深 彎曲 翻邊及其他板料成形件一般都要先沖裁 落料 出平板展開毛坯 也有成形后落料 切開得到單個(gè)成品沖件 故沖裁作業(yè) 包括常用的沖孔 切 口 切邊等 對(duì)于每種板料沖壓件都是必要的 所以沖裁間隙對(duì)沖件的外廓尺 寸精度有決定性的影響 沖裁間隙小而均勻 可使沖裁尺寸獲取更高精度 對(duì) 于拉深 彎曲等成形模 間隙大定將增大沖件口部尺寸誤差及回彈 間隙不均 勻會(huì)使沖件毛刺加大并招致刃口的不均勻磨損 5 沖壓設(shè)備的彈性變形 在沖壓過程中 沖床承載后會(huì)產(chǎn)生一定的彈性變形 雖然這種變形量依沖壓力 的大小變化且具有明顯的方向性 但就沖壓件 主要是對(duì)具有體積沖壓性質(zhì)的 壓印 壓花 校平 壓凸 起波 沖擠 鐓形 翻邊 鐓粗 打扁 變薄拉深 等工藝作業(yè)沖制成形的沖件 對(duì)其沖壓方面的尺寸精度有重大影響