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畢業(yè)設(shè)計(jì)(論文)外文翻譯
（原文）
學(xué) 院： 機(jī)電工程學(xué)院
專(zhuān) 業(yè)： 機(jī)械設(shè)計(jì)制造及其自動(dòng)化
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年 6 月 3 日
第 19 頁(yè) 共 20 頁(yè)
桂林電子科技大學(xué)畢業(yè)設(shè)計(jì)（論文）報(bào)告用紙
一、
由于歷史原因形成的封閉式、“ 大 而全” 的 企業(yè)特征，我國(guó)大部分企業(yè)均設(shè)有模具車(chē)間，處于本廠(chǎng)的配套地位，自 70 年代末才有了模具工業(yè)化和生產(chǎn)專(zhuān)業(yè)化這個(gè)概念。China’s mold industry
Due to historical reasons for the formation of closed, "big and complete" enterprise features, most enterprises in China are equipped with mold workshop, in factory matching status since the late 70s have a mold the concept of industrialization and specialization of production. 生產(chǎn)效率不高，經(jīng)濟(jì)效益較差。 Production efficiency is not high, poor economic returns. 模具行業(yè)的生產(chǎn)小而散亂，跨行業(yè)、投資密集，專(zhuān)業(yè)化、商品化和技術(shù)管理水平都比較低。 Mold production industry is small and scattered, cross-industry, capital-intensive, professional, commercial and technical management level are relatively low.
據(jù)不完全統(tǒng)計(jì)，全國(guó)現(xiàn)有模具專(zhuān)業(yè)生產(chǎn)廠(chǎng)、產(chǎn)品廠(chǎng)配套的模具車(chē)間（分廠(chǎng)）近17000家，約60萬(wàn)從業(yè)人員，年模具總產(chǎn)值達(dá)200億元人民幣。 According to incomplete statistics, there are now specialized in manufacturing mold, the product supporting mold factory workshop (factory) near 17 000, about 600 000 employees, annual output value reached 20 billion yuan mold. 但是，我國(guó)模具工業(yè)現(xiàn)有能力只能滿(mǎn)足需求量的60％左右，還不能適應(yīng)國(guó)民經(jīng)濟(jì)發(fā)展的需要。 However, the existing capacity of the mold and die industry can only meet the demand of 60%, still can not meet the needs of national economic development. 目前，國(guó)內(nèi)需要的大型、精密、復(fù)雜和長(zhǎng)壽命的模具還主要依靠進(jìn)口。 At present, the domestic needs of large, sophisticated, complex and long life of the mold also rely mainly on imports. 據(jù)海關(guān)統(tǒng)計(jì)，1997年進(jìn)口模具價(jià)值6.3億美元，這還不包括隨設(shè)備一起進(jìn)口的模具；1997年出口模具僅為7800萬(wàn)美元。 According to customs statistics, in 1997 630 million U.S. dollars worth of imports mold, not including the import of mold together with the equipment; in 1997 only 78 million U.S. dollars export mold. 目前我國(guó)模具工業(yè)的技術(shù)水平和制造能力，是我國(guó)國(guó)民經(jīng)濟(jì)建設(shè)中的薄弱環(huán)節(jié)和制約經(jīng)濟(jì)持續(xù)發(fā)展的瓶頸。 At present the technological level of China Die & Mould Industry and manufacturing capacity, China's national economy in the weak links and bottlenecks constraining sustainable economic development.
1、Research on the Structure of industrial products mold
按照中國(guó)模具工業(yè)協(xié)會(huì)的劃分，我國(guó)模具基本分為10大類(lèi)，其中，沖壓模和塑料成型模兩大類(lèi)占主要部分。 In accordance with the division of China Mould Industry Association, China mold is divided into 10 basic categories, which, stamping die and plastic molding two categories accounted for the main part. 按產(chǎn)值計(jì)算，目前我國(guó)沖壓模占50％左右，塑料成形模約占20％，拉絲模（工具）約占10％，而世界上發(fā)達(dá)工業(yè)國(guó)家和地區(qū)的塑料成形模比例一般占全部模具產(chǎn)值的40％以上。 Calculated by output, present, China accounts for about 50% die stamping, plastic molding die about 20%, Wire Drawing Die (Tool) about 10% of the world's advanced industrial countries and regions, the proportion of plastic forming die die general of the total output value 40%.
我國(guó)沖壓模大多為簡(jiǎn)單模、單工序模和符合模等，精沖模，精密多工位級(jí)進(jìn)模還為數(shù)不多，模具平均壽命不足100萬(wàn)次，模具最高壽命達(dá)到1億次以上，精度達(dá)到3～5um，有50個(gè)以上的級(jí)進(jìn)工位，與國(guó)際上最高模具壽命6億次，平均模具壽命5000萬(wàn)次相比，處于80年代中期國(guó)際先進(jìn)水平。 Most of our stamping die mold for the simple, single-process mode and meet the molds, precision die, precision multi-position progressive die is also one of the few, die less than 100 million times the average life of the mold reached 100 million times the maximum life of more than accuracy 3 ~ 5um, more than 50 progressive station, and the international life of the die 600 million times the highest average life of the die 50 million times compared to the mid 80s at the international advanced level.
我國(guó)的塑料成形模具設(shè)計(jì)，制作技術(shù)起步較晚，整體水平還較低。 China's plastic molding mold design, production technology started relatively late, the overall level of low. 目前單型腔，簡(jiǎn)單型腔的模具達(dá)70％以上，仍占主導(dǎo)地位。 Currently a single cavity, a simple mold cavity 70%, and still dominant. 一模多腔精密復(fù)雜的塑料注射模，多色塑料注射模已經(jīng)能初步設(shè)計(jì)和制造。A sophisticated multi-cavity mold plastic injection mold, plastic injection mold has been able to multi-color preliminary design and manufacturing. 模具平均壽命約為80萬(wàn)次左右，主要差距是模具零件變形大、溢邊毛刺大、表面質(zhì)量差、模具型腔沖蝕和腐蝕嚴(yán)重、模具排氣不暢和型腔易損等，注射模精度已達(dá)到5um以下，最高壽命已突破2000萬(wàn)次，型腔數(shù)量已超過(guò)100腔，達(dá)到了80年代中期至90年代初期的國(guó)際先進(jìn)水平。 Mould is about 80 million times the average life span is about, the main difference is the large deformation of mold components, excess burr side of a large, poor surface quality, erosion and corrosion serious mold cavity, the mold cavity exhaust poor and vulnerable such as, injection mold 5um accuracy has reached below the highest life expectancy has exceeded 20 million times, the number has more than 100 chamber cavity, reaching the mid 80s to early 90s the international advanced level.
2、mold Present Status of Technology
我國(guó)模具工業(yè)目前技術(shù)水平參差不齊，懸殊較大。 Technical level of China's mold industry currently uneven, with wide disparities. 從總體上來(lái)講，與發(fā)達(dá)工業(yè)國(guó)家及港臺(tái)地區(qū)先進(jìn)水平相比，還有較大的差距。 Generally speaking, with the developed industrial countries, Hong Kong and Taiwan advanced level, there is a large gap.
在采用CAD/CAM/CAE/CAPP等技術(shù)設(shè)計(jì)與制造模具方面，無(wú)論是應(yīng)用的廣泛性，還是技術(shù)水平上都存在很大的差距。 The use of CAD / CAM / CAE / CAPP and other technical design and manufacture molds, both wide application, or technical level, there is a big gap between both. 在應(yīng)用CAD技術(shù)設(shè)計(jì)模具方面，僅有約10%的模具在設(shè)計(jì)中采用了CAD，距拋開(kāi)繪圖板還有漫長(zhǎng)的一段路要走；在應(yīng)用CAE進(jìn)行模具方案設(shè)計(jì)和分析計(jì)算方面，也才剛剛起步，大多還處于試用和動(dòng)畫(huà)游戲階段；在應(yīng)用CAM技術(shù)制造模具方面，一是缺乏先進(jìn)適用的制造裝備，二是現(xiàn)有的工藝設(shè)備（包括近10多年來(lái)引進(jìn)的先進(jìn)設(shè)備）或因計(jì)算機(jī)制式（IBM微機(jī)及其兼容機(jī)、HP工作站等）不同，或因字節(jié)差異、運(yùn)算速度差異、抗電磁干擾能力差異等，聯(lián)網(wǎng)率較低，只有5%左右的模具制造設(shè)備近年來(lái)才開(kāi)展這項(xiàng)工作；在應(yīng)用CAPP技術(shù)進(jìn)行工藝規(guī)劃方面，基本上處于空白狀態(tài)，需要進(jìn)行大量的標(biāo)準(zhǔn)化基礎(chǔ)工作；在模具共性工藝技術(shù)，如模具快速成型技術(shù)、拋光技術(shù)、電鑄成型技術(shù)、表面處理技術(shù)等方面的CAD/CAM技術(shù)應(yīng)用在我國(guó)才剛起步。 In the application of CAD technology design molds, only about 10% of the mold used in the design of CAD, aside from drawing board still has a long way to go; in the application of CAE design and analysis of mold calculation, it was just started, most of the game is still in trial stages and animation; in the application of CAM technology manufacturing molds, first, the lack of advanced manufacturing equipment, and second, the existing process equipment (including the last 10 years the introduction of advanced equipment) or computer standard (IBM PC and compatibles, HP workstations, etc.) different, or because of differences in bytes, processing speed differences, differences in resistance to electromagnetic interference, networking is low, only about 5% of the mold manufacturing equipment of recent work in this task; in the application process planning CAPP technology, basically a blank state, based on the need for a lot of standardization work; in the mold common technology, such as mold rapid prototyping technology, polishing, electroforming technologies, surface treatment technology aspects of CAD / CAM technology in China has just started. 計(jì)算機(jī)輔助技術(shù)的軟件開(kāi)發(fā)，尚處于較低水平，需要知識(shí)和經(jīng)驗(yàn)的積累。 Computer-aided technology, software development, is still at low level, the accumulation of knowledge and experience required. 我國(guó)大部分模具廠(chǎng)、車(chē)間的模具加工設(shè)備陳舊，在役期長(zhǎng)、精度差、效率低，至今仍在使用普通的鍛、車(chē)、銑、刨、鉆、磨設(shè)備加工模具，熱處理加工仍在使用鹽浴、箱式爐，操作憑工人的經(jīng)驗(yàn)，設(shè)備簡(jiǎn)陋，能耗高。 Most of our mold factory, mold processing equipment shop old, long in the length of civilian service, accuracy, low efficiency, still use the ordinary forging, turning, milling, planing, drilling, grinding and processing equipment, mold, heat treatment is still in use salt bath, box-type furnace, operating with the experience of workers, poorly equipped, high energy consumption. 設(shè)備更新速度緩慢，技術(shù)改造，技術(shù)進(jìn)步力度不大。 Renewal of equipment is slow, technological innovation, technological progress is not much intensity. 雖然近年來(lái)也引進(jìn)了不少先進(jìn)的模具加工設(shè)備，但過(guò)于分散，或不配套，利用率一般僅有25%左右，設(shè)備的一些先進(jìn)功能也未能得到充分發(fā)揮。 Although in recent years introduced many advanced mold processing equipment, but are too scattered, or not complete, only about 25% utilization, equipment, some of the advanced functions are not given full play.
缺乏技術(shù)素質(zhì)較高的模具設(shè)計(jì)、制造工藝技術(shù)人員和技術(shù)工人，尤其缺乏知識(shí)面寬、知識(shí)結(jié)構(gòu)層次高的復(fù)合型人才。 Lack of technology of high-quality mold design, manufacturing technology and skilled workers, especially the lack of knowledge and breadth, knowledge structure, high levels of compound talents. 中國(guó)模具行業(yè)中的技術(shù)人員，只占從業(yè)人員的8%~12%左右，且技術(shù)人員和技術(shù)工人的總體技術(shù)水平也較低。 China's mold industry and technical personnel, only 8% of employees 12%, and the technical personnel and skilled workers and lower the overall skill level. 1980年以前從業(yè)的技術(shù)人員和技術(shù)工人知識(shí)老化，知識(shí)結(jié)構(gòu)不能適應(yīng)現(xiàn)在的需要；而80年代以后從業(yè)的人員，專(zhuān)業(yè)知識(shí)、經(jīng)驗(yàn)匱乏，動(dòng)手能力差，不安心，不愿學(xué)技術(shù)。 Before 1980, practitioners of technical personnel and skilled workers, the aging of knowledge, knowledge structure can not meet the current needs; and staff employed after 80 years, expertise, experience lack of hands-on ability, not ease, do not want to learn technology. 近年來(lái)人才外流不僅造成人才數(shù)量與素質(zhì)水平下降，而且人才結(jié)構(gòu)也出現(xiàn)了新的斷層，青黃不接，使得模具設(shè)計(jì)、制造的技術(shù)水平難以提高。 In recent years, the brain drain caused by personnel not only decrease the quantity and quality levels, and personnel structure of the emergence of new faults, lean, make mold design, manufacturing difficult to raise the technical level.
mold industry supporting materials, standard parts of present condition
近10多年來(lái)，特別是“八五”以來(lái)，國(guó)家有關(guān)部委已多次組織有關(guān)材料研究所、大專(zhuān)院校和鋼鐵企業(yè)，研究和開(kāi)發(fā)模具專(zhuān)用系列鋼種、模具專(zhuān)用硬質(zhì)合金及其他模具加工的專(zhuān)用工具、輔助材料等，并有所推廣。 Over the past 10 years, especially the "Eighth Five-Year", the State organization of the ministries have repeatedly Material Research Institute, universities and steel enterprises, research and development of special series of die steel, molds and other mold-specific carbide special tools, auxiliary materials, and some promotion. 但因材料的質(zhì)量不夠穩(wěn)定，缺乏必要的試驗(yàn)條件和試驗(yàn)數(shù)據(jù)，規(guī)格品種較少，大型模具和特種模具所需的鋼材及規(guī)格還有缺口。 However, due to the quality is not stable enough, the lack of the necessary test conditions and test data, specifications and varieties less, large molds and special mold steel and specifications are required for the gap. 在鋼材供應(yīng)上，解決用戶(hù)的零星用量與鋼廠(chǎng)的批量生產(chǎn)的供需矛盾，尚未得到有效的解決。 In the steel supply, settlement amount and sporadic users of mass-produced steel supply and demand contradiction, yet to be effectively addressed. 另外，國(guó)外模具鋼材近年來(lái)相繼在國(guó)內(nèi)建立了銷(xiāo)售網(wǎng)點(diǎn)，但因渠道不暢、技術(shù)服務(wù)支撐薄弱及價(jià)格偏高、外匯結(jié)算制度等因素的影響，目前推廣應(yīng)用不多。 In addition, in recent years have foreign steel mold set up sales outlets in China, but poor channels, technical services support the weak and prices are high, foreign exchange settlement system and other factors, promote the use of much current.
模具加工的輔助材料和專(zhuān)用技術(shù)近年來(lái)雖有所推廣應(yīng)用，但未形成成熟的生產(chǎn)技術(shù)，大多仍還處于試驗(yàn)摸索階段，如模具表面涂層技術(shù)、模具表面熱處理技術(shù)、模具導(dǎo)向副潤(rùn)滑技術(shù)、模具型腔傳感技術(shù)及潤(rùn)滑技術(shù)、模具去應(yīng)力技術(shù)、模具抗疲勞及防腐技術(shù)等尚未完全形成生產(chǎn)力，走向商品化。 Mold supporting materials and special techniques in recent years despite the popularization and application, but failed to mature production technology, most still also in the exploratory stage tests, such as die coating technology, surface treatment technology mold, mold guide lubrication technology Die sensing technology and lubrication technology, mold to stress technology, mold and other anti-fatigue and anti-corrosion technology productivity has not yet fully formed, towards commercialization. 一些關(guān)鍵、重要的技術(shù)也還缺少知識(shí)產(chǎn)權(quán)的保護(hù)。 Some key, important technologies also lack the protection of intellectual property.
我國(guó)的模具標(biāo)準(zhǔn)件生產(chǎn)，80年代初才形成小規(guī)模生產(chǎn)，模具標(biāo)準(zhǔn)化程度及標(biāo)準(zhǔn)件的使用覆蓋面約占20%，從市場(chǎng)上能配到的也只有約30個(gè)品種，且僅限于中小規(guī)格。 China's mold standard parts production, the formation of the early 80s only small-scale production, standardization and standard mold parts using the coverage of about 20%, from the market can be assigned to, is just about 30 varieties, and limited to small and medium size. 標(biāo)準(zhǔn)凸凹模、熱流道元件等剛剛開(kāi)始供應(yīng)，模架及零件生產(chǎn)供應(yīng)渠道不暢，精度和質(zhì)量也較差。 Standard punch, hot runner components and other supplies just the beginning, mold and parts production and supply channels for poor, poor accuracy and quality.
3、Die & Mould Industry Structure in Industrial Organization
我國(guó)的模具工業(yè)相對(duì)較落后，至今仍不能稱(chēng)其為一個(gè)獨(dú)立的行業(yè)。 China's mold industry is relatively backward and still could not be called an independent industry. 我國(guó)目前的模具生產(chǎn)企業(yè)可劃分為四大類(lèi)：專(zhuān)業(yè)模具廠(chǎng)，專(zhuān)業(yè)生產(chǎn)外供模具；產(chǎn)品廠(chǎng)的模具分廠(chǎng)或車(chē)間，以供給本產(chǎn)品廠(chǎng)所需的模具為主要任務(wù)；三資企業(yè)的模具分廠(chǎng)，其組織模式與專(zhuān)業(yè)模具廠(chǎng)相類(lèi)似，以小而專(zhuān)為主；鄉(xiāng)鎮(zhèn)模具企業(yè)，與專(zhuān)業(yè)模具廠(chǎng)相類(lèi)似。 Mold manufacturer in China currently can be divided into four categories: professional mold factory, professional production outside for mold; products factory mold factory or workshop, in order to supply the product works as the main tasks needed to die; die-funded enterprises branch, the organizational model and professional mold factory is similar to small but the main; township mold business, and professional mold factory is similar. 其中以第一類(lèi)數(shù)量最多，模具產(chǎn)量約占總產(chǎn)量的70%以上。 Of which the largest number of first-class, mold production accounts for about 70% of total output. 我國(guó)的模具行業(yè)管理體制分散。 China's mold industry, decentralized management system. 目前有19個(gè)大行業(yè)部門(mén)制造和使用模具，沒(méi)有統(tǒng)一管理的部門(mén)。 There are 19 major industry sectors manufacture and use of mold, there is no unified management of the department. 僅靠中國(guó)模具工業(yè)協(xié)會(huì)統(tǒng)籌規(guī)劃，集中攻關(guān)，跨行業(yè)，跨部門(mén)管理困難很多。 Only by China Die & Mould Industry Association, overall planning, focus on research, cross-sectoral, inter-departmental management difficulties are many.
模具適宜于中小型企業(yè)組織生產(chǎn)，而我國(guó)技術(shù)改造投資向大中型企業(yè)傾斜時(shí)，中小型模具企業(yè)的投資得不到保證。 Mold is suitable for small and medium enterprises organize production, and our technical transformation investment tilted to large and medium enterprises, small and medium enterprise investment mold can not be guaranteed. 包括產(chǎn)品廠(chǎng)的模具車(chē)間、分廠(chǎng)在內(nèi)，技術(shù)改造后不能很快收回其投資，甚至負(fù)債累累，影響發(fā)展。 Including product factory mold shop, factory, including, after the transformation can not quickly recover its investment, or debt-laden, affecting development.
雖然大多數(shù)產(chǎn)品廠(chǎng)的模具車(chē)間、分廠(chǎng)技術(shù)力量強(qiáng)，設(shè)備條件較好，生產(chǎn)的模具水平也較高，但設(shè)備利用率低。 Although most products factory mold shop, factory technical force is strong, good equipment conditions, the production of mold levels higher, but equipment utilization rate.
我國(guó)模具價(jià)格長(zhǎng)期以來(lái)同其價(jià)值不協(xié)調(diào)，造成模具行業(yè)“自身經(jīng)濟(jì)效益小，社會(huì)效益大”的現(xiàn)象。 Price has long been China's mold inconsistent with their value, resulting in mold industry "own little economic benefit, social benefit big" phenomenon. “干模具的不如干模具標(biāo)準(zhǔn)件的，干標(biāo)準(zhǔn)件的不如干模具帶件生產(chǎn)的。干帶件生產(chǎn)的不如用模具加工產(chǎn)品的”之類(lèi)不正常現(xiàn)象存在。 "Dry as dry mold mold standard parts, standard parts dry as dry mold with pieces of production. Dry with parts manufactured products than with the mold" of the class of anomalies exist.
2、 Basic terminology
1、Impression
The injection mould is an assenbly of parts containing within an inpression into which plastic material is injected and cooled. It is the impression which gives the moulding its form. The impression may, therefore, be defined as thatpart of the mould which imparts shape to the moulding.
The impression is formed by two mould mimbers:
（1）The cavity, which is the female portion of the mould, gices the moulding its external form.
（2）The core, which is the male portion of the mould , forms the internal shape of the moulding.
2、Cavity an core plates
The basic mould in this case consists of two plates. Into one plate is sunk the cavity which shapes the outside form of the moulding and os therefore known as the cavity plate. Similarly, the core which projects form the core plate forms the inside shape of the moulding os closed, the two plates come together forming a space between the cavity and core which is the impression.
3、Sprue bush
During the injection process plastic material is delivered to the mozzle of the machie as a melt;it is then tramsferred to the impression though a passage. The material in this passage is termed the sprue, and the bush is called a sprue bush.
4、Runner and gate systems
The material may bedirectly injected into the impression though the sprue bush or for moulds containing several impressions it may pass from the sprue bush hole through a runner and gate system therefore entering the impression.
5、Register ring
If the material is to pass without hidrance into the mould the mozzle and sprue must be correctly aligned. To endure that this is so the mould must be central to the machine and this can be achieved by including a regicter ring.
6、Guide pillars and bushes
To mould an even-walled article it is necessary to ensure that the cavity and core are keptin alignmemt. This is done by incorporating guide pillars on one mould plate which then enter corresponding guide bushes in the other mould plate as the mouls closes.
7、Fixed half and moving half
The various mould parts fall naturally into two sections or halves. Hence, that half attached to the stationary platen of the machine (indicated by the chain dotted line)is termed the fixed half, The other half of the mould attached to the moving platen of the machine is known simply as the moving half. Now it has to be situsted. Generally the core is situated in the moving half and the overriding reason why this is so, is as follows:
The moulding as it cools, will shrink on to the core and remain with it as the mould opens. This will occur irrespective of whether the core is in the fixed half or the moving half. However, this shrinkage on to the core means that some form of ejector system is almostly certainly necessary. Motivation for this ejector system iseasily provided if the core is in the moving half. Moreover, in the case of our single-impression basic mould, where a direct sprue feed to the underside of the moulding is desired the cavity must be in the fixed half and the core in the moving half.
8、Methods of incorporating cavity and core
We have now seen that in general the core is incorporsted in the moving half and the cavity in the fixed half. However, there are various methods by which the cavity and core can be incorporated in their respective halves of the mould. These represent two basic alternatives (i) the integer method where the cavity and core can be machined form steel plates which become part of the structural build-up of the mould, or (ii) the cavity and core can be machined form small blocks of steel, termed inderts, and subsequently bolstered. The choice between these alternatives constitutes an important decision on the part of the mould designer. The final result, nevertheless, will be the contains the core is termed the core plate and the plate or assembly which contains the cavity is termed the cavity plate.
9、Cavity Fabrication
When a decision for making a mold is made, the cost is predicated on producing a specified quantity of parts without additional tooling expenditure. Sometimes, the anticipatesare quantities are exceeded; other times, they all short of requirements, and costly repairs becomenecesary in order to supply the needs.
In the making of cavities by machining, grinding, or electric discharge machining, there is constant drive to improve the rate of metal removal. Cutting tools as well as machine tools are developed for heavier and faster cuts; grinding wheels are tailor-made for special steels to allow deeper cuts per pass; and EDM machines are revamped to burn the metal at an accelerated pace.It is fully appreciated that faster mental-removal rate leads to more economical manufacture,but at the same time it mast be recognized that the newer cavity fabrication is associated with generation of more heat and indirectly with higher stresses that if not relieved can cause premature gailure.
Suppliers of tool steel caution the user against fabricating stresses and strongly advise a stress-relieving operation. When a steel is to be heat-treated and a preheat cycle ia part of the heat-treating specification, then the metal-removal stresses will be eliminated.
A great number of cavities are made of prehardened steel, and therefore would not be heat-treated.For those cavities,a stress-relieving operation should be carried out immediately after fabricaton.the stress-relieving temperature as a rule is about 100oF below the tempring heat and is held for 30 min. for each inch of steel thickness. It is best to check the stress-relieving heat and time with the maker of the steel.
The information about fabrication stress has always been emphasized by the steelmakers,but for some reason it has not been given the attention it deserves. Since a tool drawing should cover all the requirements of a tool element, it would be the appropriate place for a note such as the following:
Note: For heat-treated steel:“Note: Use preheat and harden to RC ____.”
Note: For prehardened steel:“Note: Stress relieve@___oF for____hours
per____ inch of thickness.”
Every effort should be made to eliminate the invisible source of problems, namely，fabricating stresses.Mold cavities can be produced by a variety of processes. The