




已閱讀5頁,還剩9頁未讀, 繼續免費閱讀
版權說明:本文檔由用戶提供并上傳,收益歸屬內容提供方,若內容存在侵權,請進行舉報或認領
文檔簡介
模具工業是國民經濟的基礎工業,是國際上公認的關鍵工業,工業發達國家稱之為 “ 工業之母 ” 。模具成型具有效率高,質量好,節省原材料,降低產品成本等優點。采用模具制造產品零件已成為當今工業的重要工藝手段。模具在機械,電子,輕工,紡織,航空,航天等工業領域里,已成為使用最廣泛的工業化生產的主要工藝裝備,它承擔了這些工業領域中 60%-80%產品零件,組件和部件的加工生產。 “ 模具就是產品質量 ” , “ 模具就是經濟效益 ” 的觀念已被越來越多的人所認識和接受。在中國,人們已經認識到模具在制造業中的重要基礎地位,認識更新換代的速度 ,新產品的開發能力,進而決定企業的應變能力和市場競爭能力。 在目前用薄鋼板制造發動機罩蓋的傳統還是會持續相當一段時間,所以有必要在鋼板的基礎上通過利用計算機軟件的功能分析零件的工藝性能(結構合理,受力,是否容易沖出破面、),發現現有零件的不足之處,討論并確定改進這些不足之處,進而改善模具的設計,改良沖裁方式;最終實現產品的改良,改善產品的力學性能,外觀,使用效果,和造價等等。沖壓加工是通過模具來實現的,從模具角度來看,模具生產技術水平的高低,已成為衡量一個國家產品制造水平高低的重要標志,因為模具在很大程度 上決定著產品的質量、效益和新產品的開發能力。“模具是工業生產的基礎工藝裝備”也已經取得了共識。據統計,在電子、汽車、電機、電器、儀器、儀表、家電和通信等產品中, 60% 80%的零部件都要依靠模具成形。用模具生產制件所具備的高精度、高復雜程度、高一致性、高生產率和低消耗,是其他加工制造方法所不能比擬的。同時,沖壓加工也創造了巨大的價值增值,模具是“效益放大器”,用模具生產的最終產品的價值,往往是模具自身價值的幾十倍、上百倍。目前全世界模具年產值約為 600 億美元,日、美等工業發達國家的模具工業產值已超過機床工業 ,從 1997 年開始,我國模具工業產值也超過了機床工業產值。其中沖壓模具在所有模具(鍛造模、壓鑄模、注塑模等)中,無論從數量、重量或者是從價值上都位居榜首。 由此可見,板料沖壓加工及其模具制造技術對國民經濟的發展已經并將繼續作出重大的貢獻。隨著我國經濟的發展,對這種生產技術的發展及專業技術人才的需求將與日俱增。因此,加強對板料沖壓加工及其模具制造技術的研究,具有重要的意義。 現狀和發展趨勢 :經過了 100多年的發展 ,目前小型汽車發動機的罩殼的設計技術已經相當成熟的了,但是隨著各式各樣的小型發動機的開發,發動機 的前后罩也做了很大的改進。現在,對小型汽車發動機的罩殼的改進主要表現在對其構造材料的改進;例如用樹脂基復合材料替代傳統的薄鋼板,用 RTM制造 發動機水箱、隔熱罩、發動機罩等等,由于用復合材料來取代原有金屬的發動機殼體類零件,重量會有所減輕,且成本也將大大降低,對制造商而言,這個改進創造了很大了利潤空間,所以這方面的技術進步還會持續相當長一段時間。就目前而言,我國沖壓模具還存在許多問題,其中模具生產周期、質量和數量仍舊是關鍵。與國際水平相比,一般來說,我國沖壓模具生產周期要比國外先進水平長、壽命約相差一倍、 精度差距也較大。數量的不足主要反映在大型、精密、復雜、長壽命模具上。存在這些問題的主要原因是: 1)行業結構 (如企業組織結構、產品結構、技術結構和進出口結構等 )不合理: 2)企業綜合素質欠佳、設計制造水平較低、開發能力弱、管理較落后; 3 )模具人才嚴重不足 ; 4)資金投入不夠; 5)專業化、標準化、商品化程度低,協作差: 6)模具材料及相關技術落后; 7)模具生產企業的效率和效益較低,等等。 柳州 天隆 機械有限公司 所用的沖壓模具還比較落后,利用沖壓模具沖出的零件質量也不是很高,經常有起皺,尺寸和形狀精度不高,壽命短等 缺陷。同時,在排樣時的不合理更造成原材料的浪費。這些因素無不影響著公司產品質量和效益的提高。歸及以上原因主要是由于模具設計得不夠合理,考慮得不夠周全等所造成的。其次不合理的工藝設計也是造成零件質量不高的原因。 工藝設計是聯接產品設計與制造的橋梁和紐帶,合理的成形工藝設計是模具設計與制造的基礎,也是決定零件能否順利成形的關鍵,它將直接關系到產品的質量、成本、生產效率以及模具的使用壽命等方面。在現在這個科技突飛猛進的時代里,模具設計技術同樣也是在快速的發展著。模具技術未來發展趨勢主要是朝信息化、高速化生產與高精度 化發展。 而如今的市場經濟,競爭又十分激烈,要想在市場中站得住腳,那么就必須不斷的提高自己設計模具的水平,使自己設計出來的 沖壓模具更合理,沖出來的零件質量,尺寸和形狀精度,壽命以及資源利用率都能得到大幅度的提高,進而才能提高公司的效益和競爭力。 1.2 選題背景 1.2.1 近年來沖壓成形工藝與理論的研究成果 近年來,沖壓成形工藝有很多新的進展,特別是精密沖裁、精密成形、精密剪切、復合材料成形、超塑性成形、軟模成形以及電磁成形等新工藝日新月異,沖壓件的精度日趨精確,生產率也有極大提高,正在把沖壓加工提 高到高品質的、新的發展水平。 由于引入了 CAE,沖壓成形已從原來的對應力應變進行有限元等分析而逐步發展到采用計算機進行工藝過程的模擬與分析,以實現沖壓過程的優化設計。在沖壓毛坯設計方面也開展了計算機輔助設計,可以對排樣或拉深毛坯進行優化設計。 此外,對沖壓成形性能和成形極限的研究,沖壓件成形難度的判定以及成形預報等技術的發展,均標志著沖壓成形以從原來的經驗、實驗分析階段開始走上由沖壓理論指導的科學階段,使沖壓成形走向計算機輔助工程化和智能化的發展道路。 方案: 作為沖壓件要大略了解它的沖壓性能的好或者差,用 個人的經驗或者視覺的判斷就可以了,但是在要求量化的條件下,最好莫過于用機械相關的板料分析軟件;我使用 DYNAFORM 來對沖壓件分析。從分析的圖象的顏色可以判斷沖壓條件是否惡劣,給出的列表數據可以清楚得知道,拉伸的情況。依據它給出的信息,我們可以對沖壓件作出相應的改進。最后重點放在模具的設計上來。 大體步驟: 1用 CAE 軟件( DYNAFORM)分析,并討論現有零件的工藝性(沖壓性能) 2改進零件的部分外形,和加強筋分布。 3用 FASTBLANK 展料,并排樣,選出最佳排樣方案。 4進行相關運算 ,得出相關數據。描繪出大體輪廓。 5利用上面所得數據,使用 UG 畫出模具 3 維圖(數模)。 6利用上述數模 討論具體零件工藝和相關方案。 7利用 AUTOCAD 或 CAXA 繪制模具相關部件 2 維圖。 8寫課題說明書。 沖壓工藝過程的優劣,決定了沖壓件制造技術的合理性、沖壓件的質量和產品成本。 因此必須對沖壓件進行詳盡的工藝分析,分析沖壓件的結構、性能及加工難易程度,確定科學的、合理的工序方案。并在保證產品的設計要求、滿足使用條件的情況下盡量減少工序,采用適宜的材料,盡量節約用料,選擇先進且合理的加工 技術,力求生產工藝過程簡單易行,以降低生產成本,提高經濟效益。 模具 CAE 技術就是在 設計 制造模具之前,在計算機上模擬出沖壓件在模具中成形的真實過程,向用戶告知模具結構設計、工藝條件狀況是否合理,并最終為用戶提供出最佳的模具設計工藝方案,可靠性達到 80%以上。從而縮短模具設計與制造周期 2/5(對于復雜模具而言),并提高模具質量和產品合格率,進而可大幅度降低制造成本,增強產品的市場競爭力。 國內模具與國外模具的差距 當前,我國工業生產的特點是產品品種多、更新快和市場競爭激烈。在這種情況下,用戶對模具制造的要求是 “交貨期短”、“精度高”、“質量好”、“價格低”。 而供需兩旺是近幾年來我國模具市場的總體表現, 2004 年仍舊是這個格局。由于汽車、機電等工業的發展增幅回落,再加上原材料漲價,能源緊張,電力供應不足,資金周轉不暢和運費增加,所以 2004 年模具市場在供需兩旺的情況下,發展增幅也有所回落。 2005 年相比,預計要回落 5 個百分點以上。 在歐美, CAD/CAE/CAM 已成為模具企業普遍采用的技術。在 CAD 方面,目前3D 設計也達到了 70% 89%。澳大利亞 3D 設計已達到 60%,而我國只是剛剛起步。CAE 技術在歐美應用逐 漸成熟。在沖模設計中應用 CAE 軟件,模擬金屬變形過程,分析應力應變的分布,預測破裂、起皺和回彈等缺陷,我國只有少部分企業開始CAE 技術的應用。 DL 圖(沖壓工藝過程圖)設計的過程中,在沖壓工藝分析、沖壓方向的確定和工序劃分方面我國與國外水平接近。但在工藝補充面的設計和產品數模的工藝處理方面還存在著較大的差距,如過拉延部分的設計,回彈值的處理等方面國外具有豐富的經驗,特別是在高精度轎車零件的工藝設計方面與國外相比仍存在著很大的差距。 高速切削是以高切削速度、高進給速度和高加工質量為主要特征的加工技術。在國外已 是比較成熟的技術,型面加工精度 0.05mm,不需要研合間隙。修邊模刃口間隙由機加工保證;鉗裝不需要研配間隙,加工后可直接裝配合模。而國內的模具鉗工工作量仍較大。 國內的加工機床性能基本與國外設備相當,但在 NC 技術參數方面,走刀路徑、方式及技術的設計方面仍存在著差距。 另外在模具制造周期、質量方面和標準化程度方面也存在著較大的差距。 第二章 沖壓工藝過程設計 沖壓工藝過程的優劣,決定了沖壓件制造技術的合理性、沖壓件的質量和產品成本。 因此必須對沖壓件進行詳盡的工藝分析,分析沖壓件的結構、性能及加工難易程度 ,確定科學的、合理的工序方案。并在保證產品的設計要求、滿足使用條件的情況下盡量減少工序,采用適宜的材料,盡量節約用料,選擇先進且合理的加工技術,力求生產工藝過程簡單易行,以降低生產成本,提高經濟效益。 模具 CAE 技術就是在設計制造模具之前,在計算機上模擬出沖壓件在模具中成形的真實過程,向用戶告知模具結構設計、工藝條件狀況是否合理,并最終為用戶提供出最佳的模具設計工藝方案,可靠性達到 80%以上。從而縮短模具設計與制造周期 2/5(對于復雜模具而言),并提高模具質量和產品合格率,進而可大幅度降低制造成本,增強產品 的市場競爭力。 隨著現代生產制造的需要,新產品開發設計、制造的質量和周期已成為企業在市場經濟中能夠生存發展的重要決定性因素之一。計算機輔助設計 (CAD)及制造 (CAM)技術的推廣應用,不僅將產品開發的設計者們從繁重的手工制圖方式中解脫出來,同時,對加工制造業而言應該是一次巨大的革命性飛躍。然而,在并行工程 CE (ConcurrentEngineering)的概念提出和應用前,產品的 CAD CAM CAE CAPP 由于分屬不同部門的工作內容,產品的設計、制造、分析是在自上而下的串行設計中完成的,很顯然,針對 并行設計,前者在整個設計過程中受到不能及時更新的約束,很難做到產品開發制造集成同步實現,增加了開發周期和生產成本。公司完成的“國家 863 CIMS 主題”重大應用項目并行工程, 通過在新產品開發 CAD CAM CAE 過程中的實施,體現了良好的應用前景。其中, PRO E 三維設計系統在產品開發過程中沖壓模具的并行全相關參數化設計已得到很好的應用。 近年來,隨著計算機綜合應用技術的迅速發展,計算機集成制造系統 (CIMS)、并行工程 (CE)、虛擬生產 (VM)等一系列新技術將機械工程制造業帶進了一個嶄新的生產過程模式。 有關資料統計表明,我國在 863 CIMS 應用推廣過程中,相關企業均獲得了明顯的經濟和社會效益,在提高生產效率,降低成本、縮短產品周期、提高質量方面的成 績尤為突出。 “并行工程”就其意義而言是一個復雜的系統過程,它解決如何有效的將產品開發設計、工藝準備過程、制造、過程管理、經營銷售等過程合理的組織,實現獲得最佳的產品周期和成本。幾年來,公司并行工程項目的啟動和實施,在不同部門的協同應用實施仍處于不斷探索驗證的階段,其中,沖壓模具并行設計已經基本形成了較為完善的過程框架,對于模具設計制造過程,并行設計的根本實現必須由核心 CAD CAM CAE 軟件的支持,作為并行工程的設計系統平臺,公司引進了美國 PTC 公司的 PRO ENGINEER 作為 CAD CAM 軟件平臺,而沖壓成形數值模擬分析則引進了專業 CAE 分析系統 DYNAFORM,在模具展開設計前和過程中,對于模具結構設計意圖的關鍵要素利用 PRO E 建模并通過標準數據格式提交給DYNAFORM 進行計算分析,預測可行性干預改進模具結構相關參數。另外,在模具的制造上可以實現在 PR0 E 內部的 CAD CAM 無縫轉接,從而不僅可以完全體現模具設計意圖、避免工程圖紙的信息損失 ,還能夠大大縮短制造周期。 PROENGINEER 在設計過程中可以利用參數設置、關系 (Relations)、參考 (Reference)管理實現全相關 (Dependency)參數化設計,換言之,在模具設計的過程中,設計產品的任何變化都將傳遞到模具所有相關的結構件上并按照結構設計意圖自動更新。這大大提高了模具設計的效率,支持設計的反復性,高效率的進行設計更新。 PRo ENGINEER 提供了一套方法和各種工具構成了一個相對完善的 Top-Down Design 的環境, Top Down Design 是指在結構設計中的 一種組織方式,其實,不單純在 PRo E 環境下,以往在手工及二維設計過程中也體現了它的宗旨。 Top Down Design 的主題思想是以圍繞核心設計意圖進行關聯式展開設計。模具并行設計的實現一般按以下 6 個步驟來完成: (1)模具設計者參與提取產品設計過程中確定產品或原型產品的模型要素,接受或自行完成已經具備最終產品全部特點的建模。 (2)對產品進行工藝分析,以 Top-Down De sign 方式規劃確定模具重要結構件的層級骨架 (Skeletions)組織設計過程。 (3)在 Pro E 系統中圍繞產品沖壓加工建立 核心組件模型,并根據工藝需要確定結構參數,轉換數據格式提交沖壓 CAE 分析軟件 DYN 刪進行可靠性分析計算。 (4)在 Pro E 系統中進行模具設計。由于準備隨時接受來自設計部門的變更及分析結果的干預進行設計更新,需要利用建模結構、順序、參照控制、特征間關系、元件間關系、組件間關系有效的保證整個模型的可靠性,如當產品局部變更時,相應凸凹模、定位元件、固定板、上下模板結構特征等必須保證成功的再生 (Regenerate)。 (5)模具結構設計完成后,輸出二維工程圖。基于工程圖與三維建模的全相關性,無論在設計過程中還 是在今后都可確保模具局部結構變化后工程圖自動及時準確的更新。 (6)同時提交模具的 CAM 部門進行工藝分析及編程。 Pro E 系統 CAD CAM 的無縫連接,使得 NC 程序同樣可以得到更新 . 沖模在裝配前應根據沖模的結構特點和技術要求,確定合理的裝配順序和裝配方法。沖模裝配之后,必須在生產條件下進行試沖,沖出的工件按沖壓零件產品圖或試樣進行檢查驗收。如果發現不合格者,必須對沖模進行適當的調整和修理,然后再試沖,直到生產合格的沖件為止。在沖模工作一段時間后,可采用超前維修。沖模的受力只局限于刃口的附近在使用一段時 間以后,刃口處會不可避免地出現不均勻磨損和磨損溝痕,如果提前維修,可避免因凸、凹模間隙不均勻而產生附加彎矩和防止磨損溝痕產生裂紋,以提高模具壽命。 實踐證明,并行參數化設計技術在工藝準備過程中的應用,大幅度降低了產品周期,增強了設計的可靠性,同時為企業取得了巨大的經濟效益和社會效益。可以預見,計算機立用技術將在生產過程中發揮更力重要的作用,并已漸漸成為現代制造業的 個重要特征。 Mold industry is the foundation of the national economy; it is recognized as the key industry in the world; and it is also regarded as the mother of the industry in the developed countries. Molding has many advantages, such as high efficiency, good quality, economizing on raw materials, reducing the cost of the production. Manufacturing the components of the productions by molding now has become an important technological method in the industry. In the machinery, electronics, light industry, textile, aviation, aerospace and other industrial areas, molding has become the most widely used main technical equipment of the industrialized production, which undertakes the processing and production task of 60% - 80% of the product components, elements and parts in these industrial fields. The concepts that Mold is the product quality and Mold is the economic-effect have been realized and received by more and more people. In China, people have recognized the important foundation of the molding in the manufacturing industry and they have realized that the management of the crisis and the market competiveness of the enterprises depend on the speed of replacement, new product development capabilities. Currently the tradition of manufacturing the engine hood by the thin steel plates will still be last quite some time, so it is necessary to analysis the technological properties, such as the reasonable structure, the force, whether it is easy to break out the surface, on the basis of the steel plate by computer software, to find the shortcomings of the ready components, discuss and determine the improvement of these deficiencies and thus improve the mold design and the stamping method, and to realize eventually the product improvement on the mechanical properties, appearance, the results of the usage and the cost and so on. Stamping processing is achieved by the mold. From the point of mold, the level of mold production technology has become the important symbol of measuring that of the countrys manufacturing, because on a large extent the mold determines the capability of product quality, effectiveness and new product development. People have known that mold industry is the basis processes and equipment of the industrial production. According to the statistics, in the products of electronics, automobile, electrical machinery, electrical appliances, instruments, meters, home appliances and communications, 60% 80% of the parts are shaped by the molds. The characteristics of high-precision, high-complexity, high-consistency, high-productivity and low-consumption, which are acquired by the mold production, are incomparable with the other manufacturing methods. In addiction, the stamping process can create great added value. The mold is the amplifier of the value; the value of the final production made by the mold is often higher than that of the own mold dozens, or even hundreds. Nowadays, the value of the global mold annual outputting is about 60 billion U.S. dollars, and the output value of the mold industry has surpassed that of the machine tool industry in Japan, the United States and the other industrialized countries. Since 1997, Chinas output value of the mold industry has also exceeded that of the machine tool industry. Among all the molds (forging mold, die casting mold, injection mold, etc.), no matter the quantity, weight or the value of the stamping die is on the top one. Thus, sheet metal stamping and processing and the mold production technology have made and will continue make a great contribution to the development of the national economy. With the development of Chinas economy, the needs to the technology development and the technical professionals will be rising. Therefore, it is significantly important to strength the research of sheet metal stamping and processing and the mold production technology. Current Situation and Development Trends: After the 100 years development, it has already been mature that the design technology of the engine of the hood of the small-size vehicle. However, with the exploitation of the all kinds of small sized engine, a lot of improvements have been done on the front and the rear hood of the engines. In the current period, the improvements of the hood of the small-size automobiles engine are mainly manifested in the improvement of the construction materials, for example, replace the traditional thin steel plate with the resin-based composite materials and make with the engine water tank, the heat shield and the engine cover, etc. by RTM. As with composite materials replace the original metal shell type of engine parts, the weight will be reduced, and the cost will be greatly reduced; for manufacturers, this creates a great deal of profit, so the technical progress is also will continue for a long period of time. As far as it goes, there are still many problems in the Chinas stamping die, and among these problems, the mold production cycle, quality and quantity are still the keys. Compared to the international standards, in general, the productive cycle of Chinas stamping die is longer, the lifespan is shorter twice and there is a wide gap of the accuracy. The lack of quantity is mainly reflected on the large-scale, sophisticated, complex, long-life mold. The main reasons of these problems are the following: 1) the irrational industry structure (such as enterprise organizational structure, product structure, technical structure and import and export structure, etc.) 2) the weakness of the comprehensive character of the enterprise, the level of design and production, the ability of development and the management; 3) the serious shortage of the qualified personnel; 4) the shortage of the capital; 5) the low level of the specialization, standardization and commercialization and the bad collaboration: 6) the outmoded mold materials and related skill; 7) the low efficiency and benefits of the mold manufacturing enterprises, etc. The stamping dies used by Tian Long Machinery Company Ltd., Liuzhou still relatively fall behind, so the components made by the stamping dies are with the shortcomings that they are of low quality, low accuracy of the size and shape and short lifespan, and they often wrinkle. Additionally, the irrational nesting may lead to the waste of raw materials. The reasons above are mainly due to the unreasonable mold design and the incomplete consideration. Whats more, the unreasonable process design is the reason of the low quality of the components. Process design is the bridge and link between the production design and manufacture. Reasonable forming process design is the basis of mold design and manufacture, and it is also the key that whether the component can form smoothly; it is related directly to the quality, cost, efficiency of the production, and the molds lifespan and so on. In the present era, the technology developing rapidly, the technology of mold design is also in the fast developing. The tendency of the mold technology in the future is the development towards the information technology, high-speed production and precision of the development. Nowadays, competition is very intense in the market economy. In order to prevail in the market, the level of the design must be continually improved so that the stamping dies are more reasonable and the quality, size, shape accuracy, lifespan and resource utilization of the components are can be greatly enhanced, which can improve the companys efficiency and competitiveness. 1.2 Background of the topic 1.2.1 The Research Results of the of Metal Forming Technology and Research Results in Recent Years In recent years, stamping forming process there are many new advances, especially in precision stamping, precision molding, precision cutting, composite materials, forming, super plastic forming, soft-casting and the electromagnetic forming of new technology with each passing day, increasing the accuracy of precision stamping parts productivity is also greatly improved, is to improve the stamping process to high-quality, new level of development. Since CAE is introduced, the stamping process has developed to computer simulation and analysis process from making finite element analysis by the pairs of stress and strain in order to achieve optimal design. Whats more, the computer-aided design has also been launched in the stamping blank design to draw on the blank layout to optimize the design. The research on the performance of the metal stamping and forming and the limits of forming, as well as the determination on the difficulty of the stampings forming and the developing on the techniques of forming forecasting, shows that the stamping and forming begins to enter the scientific stage guided by the stamping theory from the stage of analyzing the original experience and experiments; these all help the technology of stamping and forming go to the development of stamping and intelligent computer-aided engineering. Program: As a stamping press, its rough performance, good or bad, can be the judged by personal experience or vision, but under the conditions of requiring the quantization, people would better use the sheet metal analysis software associated with the mechanism; and I use DYNAFORM to analysis the stamping parts. The color of the images in the analysis can determine that the conditions of the pressing, and we can know clearly the stretching situation by the list of data. Based on information given, we can improve correspondingly the stampings. Finally we should focus on the mold design up. General steps: 1. Analyzing by using CAE software (DYNAFORM), and discussing the manufacturability of the existing parts (stamping performance) 2. Improving some parts shape, and strengthening the tendons distribution 3. Exhibition of materials by FASTBLANK, stock layout, and selecting the best layout program 4. Making calculations, getting the associated data and depicting the general outline 5. Draw the three-dimensional mold chart (DAC) by the use of the data above and UG 6. Discussing the specific parts technology and related programs according to the model 7. Drawing the two-dimensional map of the die of the related components by AUTOCAD or CAXA. 8. Writing the topic statement. The pros and cons of the process of stamping process determine the rationality of the stamping parts manufacturing technology, the stamping parts quality and the cost of the production. Therefore the stamping parts must be made a thorough process analysis and by analyzing the structure, performance and the difficulty level of the stamping parts to choose the scientific and rational processes program. And to ensure the product design requirements, minimize the process, we could adopt the appropriate materials, save the materials, select the advanced and reasonable processing technology, and strive to the simple production process to reduce the production costs and improve the economic efficiency. Mold CAE technology is the one which simulates the real process of the stamping die forming on the computer before the design and manufacture of molds, informs the user that whether the die structure design and the process conditions are reasonable and ultimately provides users with the best mold design process program. The reliability of this technology is more than 80%. By using the technology the design and manufacturing cycle can be reduced by 2 / 5 (for complex mold case) and improve the mold quality and product qualification rate which can significantly reduce the manufacturing cost and enhance the product market competition. Gap between the Domestic and Foreign Mold At present, the characteristics of Chinas industrial production are production variety, quick updates, and the fierce market competition. In this case, the requirements of the users for mold manufacturing are the short delivery time, high precision, good quality, and low prices. That the supply and demand are both booming is the general display of Chinas mold market in recent years, and in 2004 this pattern remains. As the growth rate of the automotive, mechanical and electrical industries drops, the price of the raw material rises, the energy and the electricity is in the shortage, the capital is not enough to go round and the transportation expense is on the rise, in 2004 the growth rate of the mold market falls back, although the supply and demand condition is flourishing. The condition in 2005 is expected to be down 5 percentage points compared to 2004. In Europe and the United States, CAD / CAE / CAM have become a widely used technology in the mold enterprise. Presently the mature level of the 3D design of CAD has reached 70% 89%, and Australian 3D design 60%, while China is only just on the beginning. The Application of CAE technology in Europe and the United States has been mature. In China, only few enterprises put CAE technology which can simulate of metal deformation process, analyze the distribution of stress and strain to predict rupture, forecast the defects such as cracking, wrinkling and springback in the use during the stamping die design. In the DL Chart (stamping process diagram) design process, the stamping process analysis, the choosing of the direction of stamping and the division of the processes are close to those of foreign countries. However, there is a wide gap on the design of the additional surface in process and product processing, for example, the foreign technology has the rich experience on the design of the drawing off part and the digital-analog process, especially there is a wide disparity between the home and the domestic on the process of the high-precision car components. The high-speed cutting is a processing skill by using the high cutting speed, high feed rate and high processing quality. In foreign countries, it has been a relatively mature technology, the contour machining precision 0.05mm, which does not need to study co-gap. Machining processing makes sure the trimming die cutting edge clearance; pliers installation do not need the spotting time, so that it can be directly loaded with mold after processing. However, in China,mold fitters workload is still large. Although the performance of the domestic machine is quite equal to that of the equipment abroad, on the sector of the technological data of NC, the gap is still existed on the feeding path, method and the design. In addition, the disparity is showed on the mold manufacturing cycle, the quality and the level of standardization. Chapter II Stamping Process Project The pros and cons of the process of stamping, determines the rationality of the stamping parts manufacturing technology, stamping parts quality and the cost of production, so stamping parts must be analyzed thoroughly, which includes the analysis on the structure, performance and the difficulty level of the stamping parts, to determine the scientific and rational processes program. And to ensure the product design requirements, minimize the process, we could adopt the appropriate materials, save the materials, select the advanced and reasonable processing technology, and strive to the simple production process to reduce the production costs and improve the economic efficiency. Mold CAE technology is the one which simulates the real process of the stamping die forming on the computer before the design and manufacture of molds, informs the user that whether the die structure design and the process conditions are reasonable and ultimately provides users with the best mold design process program. The reliability of this technology is more than 80%. By using the technology the design and manufacturing cycle can be reduced by 2 / 5 (for complex mold case) and improve the mold quality and product qualification rate which can significantly reduce the manufacturing cost and enhance the product market competition. With the needs of the modern manufacturing, the invitation and design of the new production, the quality and the cycle have become the key that whether the business can survive and develop in the market economy. By the help of the promotion and application of computer-aided design (CAD) and manufacturing technology (CAM), not only the designers will be free from the heavy and complicated hand drawing method, but also it is a revolutionary huge leap to the manufacture. But before the introduction and the application of the concept of CE (Concurrent Engineering), the CAD / CAM / CAE / CAPP of the production belong to different departments, and the product design, manufacture and analysis are completed in the serial design from the head to the feet. Obviously, for the concurrent design, the former can not be updated on the time throughout the design process so that it is difficult to achieve the synchronous implementation of the productions invitation, fabrication and integration and extend the development cycle and the production costs. The National 863/CIMS theme, major application concurrent engineering projects, completed by the company reflects a promising application prospects by the implementation of the projects in the new product invitation through CAD / CAM / CAE. And, the parallel full-stamping die parameters design made by the PRO / E 3D design system in the product development process has been in a very good application. In recent years, with the rapid development of the computer comprehensive technology, Computer Integrated Manufacturing System (CIMS), Concurrent Engineering (CE), Virtual Manufacturing (VM) and a series of the other new technologies bring the mechanical engineering industry into a new production process mode. Some statistics show that the related businesses have received significant economic and social benefits when China applies and popularizes 863/CIMS; the enterprises have made a great improvement on rising production efficiency, reducing the costs, shortening product cycles and enhancing the quality. In terms of its meaning, Concurrent Engineering is a complex systematic process, which addresses the problems that how to develop and design effectively a product and to organize rationally the process preparation, manufacturing, process management, business and sales process to achieve the best product cycle and the lowest cost. During these years, the launch and implementation of the parallel project in the company are still in the exploration with the collaboration in different departments. However, the stamping die concurrent design has been basically formed into a relatively complete process framework; in the mold design and manufacturing process, the fundamental realization of the design must be realized on the support of the core CAD / CAM / CAE software, and the company introduced the PRO / ENGINEER of the U.S. PTCs as the CAD / CAM software platform which is the platform of the concurrent engineering design system. Before and in the process of the design process, the key of the die structure design is to mold by PRO / E and forming the numerical simulation is the introduction of Professional CAE analysis system DYNAFORM, in the mold before and begin, for the of the key elements of intent to use model, to calculate and analyze standard data which is put forward to DYNAFORM and to predict the feasibility of interventions, which can improve die structure parameters. Whats more, the manufacture of molds can achieve the seamless switching of the CAD / CAM in the PR0 / E, which can not only fully reflect the mold design intention and avoid the loss of information in the engineering drawings, but also can significantly shorten the manufacturing cycle. PRO / ENGINEER can use the design process parameter settings, relations, reference management to realize the total dependency parametric design, in other words, in the mold design process, any change of the production in the design will be reflected to all of the relevant structural parts and the design will be updated automatically in accordance with structural design. It greatly improves the efficiency of die design, supports the repeatability of the design, and updates the design with the high efficiency. PRo / ENGINEER provides a set of methods and makes up a relatively complete the environment of Top-Down Design, which refers to an organizational approach in the structural design, with the other kinds of tools. Actually, in the past, the hand and two-dimensional design process reflect the its purposes, as well as under the environment of PRo / E. Around the core theme of the design Top-Down Design commences correlation design. The realization of die concurrent engineering is completed by the following six steps in general: (1) Participate in the process of extraction of the model elements in the product or prototype product, and accept or self-complete the final product which already has all the characteristics of the model. (2) Analyze to the
溫馨提示
- 1. 本站所有資源如無特殊說明,都需要本地電腦安裝OFFICE2007和PDF閱讀器。圖紙軟件為CAD,CAXA,PROE,UG,SolidWorks等.壓縮文件請下載最新的WinRAR軟件解壓。
- 2. 本站的文檔不包含任何第三方提供的附件圖紙等,如果需要附件,請聯系上傳者。文件的所有權益歸上傳用戶所有。
- 3. 本站RAR壓縮包中若帶圖紙,網頁內容里面會有圖紙預覽,若沒有圖紙預覽就沒有圖紙。
- 4. 未經權益所有人同意不得將文件中的內容挪作商業或盈利用途。
- 5. 人人文庫網僅提供信息存儲空間,僅對用戶上傳內容的表現方式做保護處理,對用戶上傳分享的文檔內容本身不做任何修改或編輯,并不能對任何下載內容負責。
- 6. 下載文件中如有侵權或不適當內容,請與我們聯系,我們立即糾正。
- 7. 本站不保證下載資源的準確性、安全性和完整性, 同時也不承擔用戶因使用這些下載資源對自己和他人造成任何形式的傷害或損失。
最新文檔
- 武漢體育學院體育科技學院《食用真菌學》2023-2024學年第二學期期末試卷
- 山西省朔州市懷仁市重點中學2025屆高三下學期聯合物理試題含解析
- 認識新規范 爭做文明人
- 2025商業店鋪租賃保證金合同樣本
- 2025農產品買賣合同
- 2025標的物買賣合同標準格式
- 2025國際租賃合同 標準版 模板
- 規劃7路技術標
- 2025農副產品采購招標合同范本
- 2025年普法知識競賽題庫及答案(共70題)
- 壓電陶瓷精品課件
- 教學課件·植物組織培養
- 紙包裝生產企業設備管理課件
- 部編版語文一年級下冊識字8-人之初市級優質課課件
- 基于仿真的軸承動力學分析設計畢業設計說明書
- 麗聲北極星分級繪本第二級下Eek,Spider 教學設計
- (高清正版)JJF 1908-2021 雙金屬溫度計校準規范
- 測量成果驗收單
- 畢業設計(論文)-助力式下肢外骨骼機器人的結構設計
- 云南省學業水平考試網絡管理系統培訓
- 曝氣管安裝【曝氣設備】質量檢驗模板
評論
0/150
提交評論