沖壓件墊板零件沖壓模具設(shè)計【止動件落料沖孔復(fù)合?！俊菊f明書+CAD+PROE】,止動件落料沖孔復(fù)合模,說明書+CAD+PROE,沖壓件墊板零件沖壓模具設(shè)計【止動件落料沖孔復(fù)合?！俊菊f明書+CAD+PROE】,沖壓,墊板,零件,模具設(shè)計,止動件落料,沖孔,復(fù)合,說明書,仿單,cad 目 錄 前言……………………………………………………………………………………1 第一章 專業(yè)課程設(shè)計概述………………………………………………………… 2 1.1 專業(yè)課程設(shè)計的目的和要求……………………………………………… 2 1.1.1 專業(yè)課程設(shè)計的目的……………………………………………………2 1.1.2 專業(yè)課程設(shè)計的要求……………………………………………………2 1.2 專業(yè)課程設(shè)計的內(nèi)容………………………………………………………3 1.2.1專業(yè)課程設(shè)計課題………………………………………………………3 1.2.2 專業(yè)課程設(shè)計時間安排…………………………………………………3 1.2.3 專業(yè)課程設(shè)計工作量……………………………………………………4 第二章 冷沖壓工藝與模具設(shè)計、模具制造工藝……………………………………4 2.1 沖壓工藝性分析……………………………………………………………4 2.2 工藝方案確定………………………………………………………………5 2.3 確定模具類型及結(jié)構(gòu)形式…………………………………………………5 2.4 工藝計算……………………………………………………………………6 2.5 編寫工藝文件………………………………………………………………9 2.6 選擇和確定模具主要零部件的結(jié)構(gòu)和尺寸………………………………10 2.7 校核所選壓力機(jī)……………………………………………………………11 2.8 編制工作零件機(jī)械加工工藝卡……………………………………………12 第三章 塑料成型工藝與模具設(shè)計、模具制造工藝………………………………13 3.1 工藝分析……………………………………………………………………14 3.2 成型設(shè)備的選擇與模塑工藝參數(shù)的確定…………………………………14 3.3 模具結(jié)構(gòu)方案及尺寸的確定………………………………………………15 3.3.1選擇制品的分型面……………………………………………………15 3.3.2 型腔布置………………………………………………………………16 3.3.3澆注系統(tǒng)………………………………………………………………16 3.3.4 溢流、排氣系統(tǒng)的設(shè)計………………………………………………17 3.3.5 選擇脫模方式…………………………………………………………17 3.3.6 成型零件工作尺寸的計算……………………………………………17 3.3.7 模具主要零件的結(jié)構(gòu)和尺寸設(shè)計……………………………………18 3.3.8 模具調(diào)溫系統(tǒng)的設(shè)置…………………………………………………18 3.4 注射機(jī)有關(guān)工藝參數(shù)的校核………………………………………………19 3.5 編寫工藝零件機(jī)械加工工藝………………………………………………20 結(jié)束語………………………………………………………………………………21 前 言 在“十五”規(guī)劃中，模具被認(rèn)為是“工業(yè)生產(chǎn)的基礎(chǔ)工藝裝備”，國民經(jīng)濟(jì)的五大支柱產(chǎn)業(yè)機(jī)械、電子、汽車、石化、建筑都要求模具工業(yè)發(fā)展與之相適應(yīng)。中國成模具制造大國當(dāng)今世界正進(jìn)行著新一輪的產(chǎn)業(yè)調(diào)整，一些模具制造逐漸向發(fā)展中國家轉(zhuǎn)移，中國正成為世界模具大國。 現(xiàn)代模具行業(yè)是技術(shù)、資金密集的行業(yè)。它作為重要的生產(chǎn)裝備行業(yè)在為各行各業(yè)服務(wù)的同時，也直接為高新技術(shù)產(chǎn)業(yè)服務(wù)。模具是工業(yè)生產(chǎn)中使用廣泛的基礎(chǔ)工藝裝備。有人說，現(xiàn)代模具是高技術(shù)背景下的工藝密集型工業(yè)。模具技術(shù)水平的高低，在很大的程度上決定著產(chǎn)品的質(zhì)量、效益和新產(chǎn)品的開發(fā)能力，因此已成為衡量一個國家產(chǎn)品制造水平高低的重要標(biāo)志。 我國沖壓模具無論在數(shù)量上，還是在質(zhì)量、技術(shù)和能力等方面都已有了很大發(fā)展，但與國發(fā)經(jīng)濟(jì)需求和世界先進(jìn)水平相比，差距仍很大，一些大型、精度、復(fù)雜、長壽命的高檔模具每年仍大量進(jìn)口，特別是中高檔轎車的覆蓋件模具，目前仍主要依靠進(jìn)口。一些低檔次的簡單沖模，已趨供過于求，市場竟?fàn)幖ち摇? 同時，隨著經(jīng)濟(jì)的發(fā)展注塑模具也飛速發(fā)展起來，因?yàn)樽⑺苣?yōu)點(diǎn)很多。塑料具有質(zhì)量輕、比強(qiáng)度大、絕緣性好、成型生產(chǎn)率高和價格低廉等特點(diǎn)。塑料已成為金屬的子代用材料，出現(xiàn)了金屬材料塑料化的趨勢。2)由于汽車輕量化、低能耗的發(fā)展要求，汽車零部件的材科構(gòu)成發(fā)生明顯的以塑代鋼的變化。從國內(nèi)外汽車塑料應(yīng)用的情況看，汽車塑料的用量已成為衡量汽車生產(chǎn)技術(shù)水平的重要標(biāo)志。3)注塑成型由于可以一次成型各種結(jié)構(gòu)復(fù)雜、尺寸精密和帶有金屬嵌件的制品，并目成型周期短，可以—模多腔，大批生產(chǎn)時成本低廉，易于實(shí)現(xiàn)自動化生產(chǎn)，因此在塑料加行業(yè)中占有非常重要的地位。 本設(shè)計是通過設(shè)計復(fù)合冷沖模和注塑模來熟悉模具設(shè)計與制造工藝，了解其內(nèi)部的結(jié)構(gòu)和工作原理，加深對所學(xué)習(xí)的知識的理解。 由于本人所學(xué)模具知識水平有限，視野狹小,在設(shè)計中還存在這樣那樣的問題和錯誤，敬請老師批評指正。 第一章 專業(yè)課程概述 1.1專業(yè)課程設(shè)計的目的和要求 專業(yè)課程設(shè)計是材料成型及控制工程專業(yè)教學(xué)中重要的實(shí)踐教學(xué)環(huán)節(jié)之一，它是在沖壓工藝于模具設(shè)計、塑料成型工藝于模具設(shè)計、模具制造工藝三門理論課程教學(xué)之后，為了加強(qiáng)學(xué)生所學(xué)的知識和提高學(xué)生的初步設(shè)計能力及實(shí)際動手能力二開設(shè)的實(shí)踐性教學(xué)環(huán)節(jié)。 1.1.1專業(yè)課程實(shí)際的目的 1、綜合運(yùn)用和鞏固本課程及有關(guān)課程的基礎(chǔ)理論和專業(yè)知識，培養(yǎng)學(xué)生從事模具設(shè)計于制造的初步能力，為后續(xù)畢業(yè)設(shè)計和實(shí)際工作打下良好的基礎(chǔ)。 2、培養(yǎng)學(xué)生分析問題和解決問題的能力。經(jīng)過課程設(shè)計環(huán)節(jié)，學(xué)生能全面理解和掌握沖壓工藝、塑料成型工藝、模具設(shè)計、模具制造、等內(nèi)容；掌握沖壓工藝、塑料成型工藝、模具設(shè)計的基本方法和步驟、模具零件的常用加工方法及工藝規(guī)程的編制；獨(dú)立解決在制定沖壓工藝規(guī)程、設(shè)計模具結(jié)構(gòu)、編制模具零件加工工藝規(guī)程中出現(xiàn)的問題；會查閱技術(shù)文獻(xiàn)和資料，以完成從事本專業(yè)技術(shù)工作的人員在模具設(shè)計與制造方面所必須具備的基本能力訓(xùn)練。 3、在課程設(shè)計中，培養(yǎng)學(xué)生認(rèn)證負(fù)責(zé)、踏實(shí)細(xì)致的工作作風(fēng)和眼睛的科學(xué)態(tài)度，強(qiáng)化質(zhì)量意識和時間觀念，養(yǎng)成良好的職業(yè)習(xí)慣。 1.1.2 專業(yè)課程設(shè)計要求 1、樹立正確的設(shè)計思想，盡量結(jié)合生產(chǎn)實(shí)際，結(jié)合考慮技術(shù)性、經(jīng)濟(jì)性、實(shí)用性、可靠性、安全及先進(jìn)性等方面的要求，嚴(yán)肅認(rèn)真地進(jìn)行設(shè)計。 2、獨(dú)立擬定指定制件的成型工藝，正確選擇成型設(shè)備。 3、合理確定模具結(jié)構(gòu)，很據(jù)制件圖及模具要求，提出模具結(jié)構(gòu)方案，并使其結(jié)構(gòu)合理，質(zhì)量可靠，操作方便。必要時可根據(jù)模具設(shè)計和加工要求，提出修改制件圖紙的要求，但這必須征得用戶同意后方可實(shí)施。 4、正確確定模具成型零件的形狀和尺寸。所設(shè)計的模具應(yīng)當(dāng)模具零部件加工工藝性好、制造方便、造價便宜、裝配調(diào)整、維護(hù)維修方便。模具使用效率高，安全可靠，使用壽命長。 5、充分考慮制件的設(shè)計特色，盡量減少后加工工序。 6、要求所編制的模具零件加工工藝規(guī)程符合生產(chǎn)實(shí)際，技術(shù)經(jīng)濟(jì)性。 7、設(shè)計說明書要求文字通順、條理清晰、書寫工整。圖紙圖面整潔、標(biāo)注齊全、圖樣及標(biāo)注符合國家標(biāo)準(zhǔn)。 1.2 專業(yè)課程設(shè)計的內(nèi)容 1.2.1 專業(yè)課程設(shè)計課題 專業(yè)課程設(shè)計所用的制件盡量從生產(chǎn)實(shí)踐中選取，要求該零件具有一定的典型意義。沖壓模具課題：選用只有兩道工序的制件，擬定用沖孔—落料復(fù)合?；騼傻拦ば虻倪B續(xù)模作為制件的成型方法，設(shè)計模具、編寫模具工作零件的加工工藝作為設(shè)計題目。塑料模具課題：選擇無側(cè)向抽芯的塑料件，擬定用注射模成型的方法，設(shè)計模具、編寫模具工作零件的加工工藝作為設(shè)計題目。 1.2.2專業(yè)課程設(shè)計時間安排 表1.1 專業(yè)課程設(shè)計安排表 項(xiàng)目 工藝與設(shè)計 畫裝配圖 畫零件圖 編制模具制造工藝卡片 整理、答辯 沖裁模 2-3天 2.5天 1-1.5天 0-1天 2天 注射模 2-3天 2.5天 1-1.5天 0-1天 2天 1.2.3 專業(yè)課程設(shè)計工作量 1、沖裁模具、塑料注塑模具裝配圖各一張。 2、沖裁模具、塑料注射模具工作零件圖。 3、沖模、塑模工作零件（各一份）機(jī)械加工工藝卡各一份（附在說明書）。 4、模具設(shè)計說明書一份，字?jǐn)?shù)要求10000-15000字。 第二章 冷沖壓工藝與模具設(shè)計、模具制造工藝 工件如下圖，材料Q235，料厚1mm，表面不允許有明顯的劃痕。 技術(shù)要求：1 未注圓角為R1 2 未注公差為IT14級 3 材料厚度t=1mm 圖2.1 制件圖 2.1 沖壓工藝性分析 1、材料：該零件的材料為Q235，是普通的碳素工具鋼，板厚為1mm，具有良好的可沖壓性能。 2、該零件的形狀比較簡單、規(guī)則，并在轉(zhuǎn)角處有R1的圓角過渡，孔邊距較大，且孔的尺寸是φ8，工藝性較好。 3、尺寸精度，零件上所有孔的位置精度為IT12—IT14，尺寸精度為IT13，其余尺寸都是未注公差，屬于自由公差，精度比較低，符合沖裁件的工藝性要求。查公差表可以得到如圖所示的結(jié)果。 結(jié)論：適合沖壓。 2.2 工藝方案確定 該工件包括落料、沖孔另個基本工序： 方案一：先落料，后沖孔，采用單工序模生產(chǎn)。 方案二：落料沖孔復(fù)合沖壓，采用復(fù)合模生產(chǎn)。 方案三：沖孔落料級進(jìn)沖壓，采用級進(jìn)模生產(chǎn)。 方案一模具結(jié)構(gòu)簡單，但需要兩道工序兩副模具，成本高而生產(chǎn)率低，難以滿足大中批量生產(chǎn)需求。 方案二只需一副模具，工件的精度及生產(chǎn)效率都很高。 方案三也只需一副模具，生產(chǎn)效率高，操作方便，但位置精度不如復(fù)合模具沖裁精度高。 通過對以上三種方案的分析比較，成型該零件采用方案二復(fù)合模具成型。 2.3 確定模具類型及結(jié)構(gòu)形式 1、該零件質(zhì)量要求不高，板厚1mm，孔邊距較大,為了保證零件的精度，可以選用正裝復(fù)合模。 2、定位方式的選擇：控制條料的送進(jìn)方向采用兩個導(dǎo)料銷，控制條料的送進(jìn)步距采用擋料銷。 3、卸料、出件方式的選擇：采用彈性卸料、上出件，下模剛性頂件。 4、導(dǎo)向方式的選擇：為了方便操作，該模具采用后側(cè)導(dǎo)柱的導(dǎo)向方式。 沖壓件的形狀簡單，精度要求也不高，為了使得模具的壽命較高，采用有導(dǎo)向、彈性卸料、下出件的模具結(jié)構(gòu)形式。 2.4 工藝計算 1、確定最佳排樣方式，并計算材料利用率，選擇板料的規(guī)格。 該零件為較規(guī)則的矩形零件，可直接設(shè)置為斜排排樣方式，如圖： 圖2.2 查《沖壓手冊》表2—18，最小搭邊值為： 工件間2mm 側(cè)面1.5mm 工件面積：1171.2mm2 斜排：取搭邊值1.2mm 條料寬度：B=57.45mm 步距：L=36mm 材料利用率：η=1171.2/（57.45×36）=56.6％ 選用1×2500mm×1250mm,可以裁43條，每條可以沖34件。 總的材料利用率：43×34×1171.2/(2500×1250)=55％ 2、計算沖壓合力并預(yù)選沖床 L=145mm+37.7mm=182.7mm t=1mm σ=450MP 沖壓力：F=Ltσ=182.71450=82.2KN 查《沖壓工藝及模具設(shè)計》表3-11 K=0.05 K=0.055 K=0.06 卸料力：F= KF=0.0582.2KN= 4.1KN 正裝復(fù)合模：頂件力F頂 = KF=0.06×82.2=5KN 沖裁合力F=F＋K＋F=91.3KN 根據(jù)沖壓合力預(yù)選 J23-16的曲柄壓力機(jī) 3、確定沖裁壓力中心 先求x x1=0 x2=4.5 x3=9 x4=17 x5=25 x6=33.5 x7=42 x8=50 x9=58 x10=51.5 x11=45 x12=41.5 x13=38 x14=29 x15=20 x16=16.5 x17=13 x18=6.5 x19=13 x20=45 L1=28 L2=9 L3=8 L4=16 L5=8 L6=17 L7=8 L8=16 L9=36 L10=13 L11= 8 L12= 7 L13=8 L14=18 L15=8 L16=7 L17=8 L18=13 L19=L20=8π x=∑x i×Li/∑Li=8444.96/286.2=29.5 再求y y1=14 y2=28 y3=32 y4=36 y5=32 y6=28 y7=32 y8=36 y9=18 y10=0 y11=4 y12=8 y13=4 y14=0 y15=4 y16=8 y17=4 y18= 0 y19=18 y20=18 y=∑yi ×Li/∑Li=4832.32/286.2=16.93 取x=29.5mm y=17作為模具的壓力中心的位置 4、確定沖裁凸模和凹模工作刃口尺寸 落料以落料凹模為基準(zhǔn)計算，落料凸模根據(jù)凹模和最小間隙計算，也可根據(jù)據(jù)凹模實(shí)際尺寸和間隙值配制。沖孔以沖孔凸模為基準(zhǔn)計算，沖孔凹模根據(jù)凸模和最小間隙計算，也可根據(jù)凸模十幾尺寸和間隙值配制。沖孔用分別加工法計算，落料、中心尺寸用配合加工法進(jìn)行計算。 間隙差《沖壓工藝及模具設(shè)計》 表3—4，Z=0.1mm Z=0.14 落料凹模磨損后變大的尺寸20、14、26、2，凹模公差按△/4 磨損系數(shù)查《沖壓工藝及模具設(shè)計》 表3-5 A1=（20－0.5×0.74）=19.63 A2=（14－0.5×0.27）=13.86 A3=（26－0.5×0.62）=25.69 A4=（2－0.5×0.27）=1.86 沖孔凸模磨損后變小尺寸6 公差為IT13級 凸、凹模公差按IT8級，δ=0.018mm δ=0.018mm 校核間隙＋=0.018＋0.018=0.036＜0.14－0.1＝0.04 可行 磨損系數(shù)查《沖壓工藝及模具設(shè)計》 表3-5，X=0.5。 B1＝（6＋0.5×0.16）＝6.08 B1＝（6.08＋0.1）＝6.18 5、確定彈性元件 聚氨脂橡皮允許承受的載荷較彈簧大，而且安裝調(diào)整方便，所以選用橡皮。 卸料力為F=4.1KN 橡皮的高度：H=H/(0.25-0.3)=23.3—28 取25 式中H=t+1+H=1+1+5=7 (H=4—7) 橡皮的面積：A=卸料力F/p=20385—10600mm 式中p為橡皮預(yù)壓（壓10％—15％H）的單位面積上的壓力，取0.26—0.5 取一塊整開凸?？缀退膫€卸料螺釘孔140×140×25 面積校核：140×140－3500－4×8×3.14=15296.16mm＞10600mm 可行 2.5 編寫工藝文件 表2.1 沖壓工藝過程卡 材料牌號規(guī)格 材料技術(shù)要求 毛坯尺寸 每件毛坯可制件數(shù) 毛坯重量 輔助材料 Q235（1×2500×1250） 條料（1×57.45×1250） 34件 工序號 工序名稱 工序內(nèi)容 加工簡圖 設(shè)備 工藝裝備 0 下料 剪板機(jī)上裁板 57.45×1250 1 落料 沖孔 落料沖孔復(fù)合沖裁 J23-16 落料沖孔復(fù)合模 2.6 選擇和確定模具主要零部件的結(jié)構(gòu)和尺寸 1、工作零件的結(jié)構(gòu)及尺寸設(shè)計 （1） 凸凹模：為了便于加工，凸凹模設(shè)計成直通型，1個M8沉頭螺釘固定在墊板上，與凸凹模固定板的配合按H7/m6。 其總長L=H固定板+H卸料板+（H橡膠－H預(yù)壓）=52mm （2） 凹模：凹模采用薄凹模結(jié)構(gòu)，薄凹模厚度尺寸（可以參考單工序凹模的厚度計算方法H=Ks=0.24×58=13.9mm）取14mm。 凹模壁厚尺寸 C=（1.5—2）H≥30—40mm 取C=32 式中Ks查《沖壓工藝及模具設(shè)計》 表3—15，取0.24 工件長邊尺寸：b=54.5mm 凹模板邊長： B≥58+2×(30~40)=118~138 一般選取L>B 故取B=140 L=140，故薄凹模板長、寬、厚度尺寸140×140×14mm，空心墊板長、寬、厚度尺寸160×140×25mm （3）沖孔凸模：沖孔凸模采用臺階式，與凸模固定板的配合按H7/m6。 其總長：L=H固定板+H凹模+H空心墊板=45mm （4）模具剛性校核 凸凹模尺寸較大，模具強(qiáng)度較大，所以不需要進(jìn)行模具強(qiáng)度校核。 小凸模：單個凸模所受力： 沖裁力：37.7X450=17KN 沖裁合力：11.3=11300 N Lmax≤95d/=95×8/=57.2mm﹥30 無導(dǎo)向 可行 2、其他板的尺寸[參考典型組合結(jié)構(gòu)（GB2872.1-81）] 凸凹模墊板：140×140×6 凸凹模固定板：140×140×18 卸料板：160×140×15 空心墊板：160×140×15 小凸模固定板：160×140×20 小凸模墊板：160×140×10 3、模架的規(guī)格 上模座的規(guī)格：140×140×35 下模座的規(guī)格：140×140×40 模柄的規(guī)格：A30×50mm 導(dǎo)套：A25H7×80×33 導(dǎo)柱：A25h6×130 4、模具的閉合高度的計算 H=219.5mm 2.7 校核所選壓力機(jī) J23-16壓力機(jī)：標(biāo)稱壓力 160KN；滑塊行程55（次/min）；連桿調(diào)節(jié)高度45mm；最大裝模高度220mm，工作臺尺寸（前后×左右）300×450mm，模柄孔尺寸（直徑×深度）φ30×50，電機(jī)功率1.5KW。校核以上所有參數(shù)，均可以滿足使用要求。所以J23-25能滿足該模具的使用要求。 2.8 編制工作零件機(jī)械加工工藝卡 表2.2 凹模機(jī)械加工工藝規(guī)程卡 凹模機(jī)械加工工藝規(guī)程 材料Cr12MoV 硬度 60~64 序號 工序名稱 工序內(nèi)容 1 備料 鍛件（退火狀態(tài)） 165×145×30 2 粗銑 銑六面尺寸160.3×140.3×25.5 。注意兩大平面與兩相鄰側(cè)面用標(biāo)準(zhǔn)角度尺測量達(dá)到基本垂直要求。 3 磨平面 磨光兩大平面厚度達(dá)25.3mm，并磨四個側(cè)面，達(dá)到兩相鄰側(cè)面垂直，垂直度0.02mm/100mm 4 鉗工 ①劃線 劃出孔和凹模洞口穿絲孔中心線 ②鉆孔 鉆螺紋、銷釘?shù)卓缀桶寄６纯诖┙z孔 ③鉸孔 鉸銷釘孔到要求 ④攻絲 攻螺紋孔到要求 5 熱處理 淬火+低溫回火 使材料硬度達(dá)到60-64HRC 6 磨平面 磨光六個面 消除淬火變形和氧化皮，并達(dá)到工藝所要求的尺寸 7 退磁 消除坯料殘余磁 8 線切割 割凹模洞口，并留0.01-0.02的研磨余量 9 鉗工 研磨凹模洞口內(nèi)壁側(cè)面到尺寸，粗糙度Ra值0.8μm 10 檢驗(yàn) 按圖紙檢驗(yàn) 12 General all-steel punching die’s punching accuracy Author：John J. Craig 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 0.025μm. 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. 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 12.5μm, 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 <= 8%t (unilaterally) III kindof big gap punching, will flush a fixed error to enlarge 40% ~ 60%, theprecision at least will fall a level. Side in addition, whether thereis picks builds a row of type side, flushes a error to have far to bebigger than has builds a row of type to flush. Side not builds a rowof type to flush. Side not builds a row of type to flush a precisionto be lower than the IT12 level side, but most has builds a row oftype to flush a precision in IT11 between ~ IT9 level, material thickt > 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 than1.6μm. 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 From:<>