喜歡這套資料就充值下載吧。。。資源目錄里展示的都可在線預(yù)覽哦。。。下載后都有,,請(qǐng)放心下載,,文件全都包含在內(nèi),,【有疑問(wèn)咨詢QQ:1064457796 或 1304139763】
畢業(yè)設(shè)計(jì)(論文)中期報(bào)告
題目: 吸盤式電腦攝像頭底座的模具設(shè)計(jì)
系 別 機(jī)電工程學(xué)院
專 業(yè) 機(jī)械設(shè)計(jì)制造及其自動(dòng)化
班 級(jí)
姓 名
學(xué) 號(hào)
導(dǎo) 師
2013年 3 月 21日
1.設(shè)計(jì)(論文)進(jìn)展?fàn)顩r
1.1模具結(jié)構(gòu)設(shè)計(jì)
1.1.1型腔數(shù)目的確定
由于該塑件尺寸不大,而且成規(guī)則的圓柱體,只能采用一模四腔生產(chǎn)模具可保證塑件的表面的粗糙度和質(zhì)量,又能達(dá)到制件的最佳的技術(shù)經(jīng)濟(jì)性。
1.1.2分型面的設(shè)計(jì)
分型面是決定模具結(jié)構(gòu)形式的重要因素,它與模具的整體結(jié)構(gòu)和模具的制造工藝有密切的關(guān)系,并且直接影響到塑料熔體的流動(dòng)充填特性及塑件的脫模,因此分型面的選擇是注塑模具設(shè)計(jì)中的一個(gè)關(guān)鍵選擇分型面應(yīng)遵循以下幾項(xiàng)基本原則:
a、分型面應(yīng)選在塑件外形最大輪廓處。
b、確定有利的留模方式,便于塑件順利脫模;
c、保證塑件的精度要求;
d、滿足塑件外觀質(zhì)量的要求;
e、便于模具的加工與制造;
f、對(duì)成型面積的影響;
g、排氣的效果的考慮;
h、對(duì)側(cè)向抽芯的影響。
注射模一般的有一個(gè)分型面,有的有兩個(gè)分型面。分型面的形狀分為:平直分型面,傾斜分型面,階梯分型面,曲面分型面,復(fù)合分型面。在這里考慮到塑件分型面選在塑件外形最大輪廓處,要保證有利的留模方式,要便于塑件順利脫模,保證塑件的精度要求,便于模具加工、脫模,采用平直分型面。如圖;
1.1.3注射機(jī)的選定
以鎖模力為技術(shù)參數(shù),必須大于模具在開(kāi)模方向的投影面積上的總注射力。P=PB x KC x KS式中:
P-----型腔內(nèi)注射壓力 Mpa
PB-----基本壓力 Mpa
KC---材料系數(shù),TRP材料取KC=1.15
KS---塑料復(fù)雜系數(shù),KS=1~1.5。
螺桿(柱塞)直徑(毫米)
Φ42
噴嘴
球半徑(毫米)
12
孔直徑(毫米)
Φ4
注射容量(厘米或克)
125
定位孔直徑(毫米)
Φ100
注射壓力
1190
頂出
中心孔徑(毫米)
兩側(cè)
孔徑(毫米)
?22
孔距(毫米)
230
鎖模力(10)
450
模具厚度(毫米)
最大
300
最小
200
最大注射面積(厘米)
320
模板厚度(毫米)
300
PB與塑件平均壁厚T,進(jìn)澆口流程長(zhǎng)度L的流程比L/T有關(guān),本塑件T=4mm,在這里直澆口,估算L=100mm,故L/T=33,PB=32MPa,由于該塑件簡(jiǎn)單,取KS=1,則:
P=32 ×1.15 ×1=36.8 MPa
鎖模力為;F=1.5×P×A×0.1式中;
F---所需的鎖模力 KN
P---型腔內(nèi)注射壓力
A---塑件投影面積,
A=660×510=336600
F=1.5×36.8×336600×0.1=185.803 KN
1.1.4主流道的設(shè)計(jì)
主流道的設(shè)計(jì)參考教材《塑料成型工藝與模具設(shè)計(jì)》P114表5-2主流的部分尺寸:
查教材《塑料成型工藝與模具設(shè)計(jì)》P103表4.2常用熱塑性塑料注射機(jī)型號(hào)和主要技術(shù)規(guī)格XS-ZY-125:
噴嘴球半徑=ф12㎜;
主流道小端直徑=6㎜。
則主流道小端直徑d=6+1=7㎜;
球面配合高度h取10㎜;
主流道錐角α取30;
主流道球面直徑SR=12+8=20㎜;
L和D還待定,因?yàn)槎0搴穸群蛣?dòng)模底板總長(zhǎng)為120,所以澆口套L=120mm。經(jīng)計(jì)算d=2+1=3mm。
1.1.5 澆口的設(shè)計(jì)。
因?yàn)樵撍芗怯靡荒?件型腔模,而且塑件表面粗糙度要求較高,澆口開(kāi)在成型件的底部,才用邊緣型澆口,如下圖所示。
1.1.6澆口位置的選擇
澆口的形式很多,但無(wú)論采取什么形式的澆口,其開(kāi)設(shè)的位置對(duì)塑件的成型性能及成型質(zhì)量影響都很大。在模具設(shè)計(jì)時(shí),澆口位置及尺寸要求比較嚴(yán)格,它一般根據(jù)下述幾項(xiàng)原則來(lái)參考:
盡量縮短流動(dòng)距離
a. 澆口應(yīng)開(kāi)設(shè)在塑件壁最厚處
b. 避免熔體破裂現(xiàn)象引起塑件的缺陷
c. 考慮分子定向的影響
d. 減少或避免熔接痕提高熔接強(qiáng)度
e. 應(yīng)有利于型腔中氣體的排除
f. 不在承受彎曲或沖擊載荷的部位設(shè)置澆口
g. 澆口位置的選擇應(yīng)注意塑件外觀質(zhì)量
綜合以上原則和塑件形狀及技術(shù)要求決定將澆口設(shè)置在塑件底部。
1.1.7 冷料穴和拉料桿的設(shè)計(jì)
冷料穴的作用是容納澆注系統(tǒng)流道中料流的前鋒冷料,以免這些冷料注入行腔。為了使料流的流動(dòng)性更好,在模具內(nèi)溫度更均勻.
1.1.8排氣系統(tǒng)的設(shè)計(jì)
當(dāng)塑料溶體填充型腔時(shí),必須將型腔內(nèi)和澆注系統(tǒng)內(nèi)的空氣及塑料受熱或凝固產(chǎn)生的低分子揮發(fā)氣體順利排出模外。如果型腔內(nèi)因各種因素沒(méi)有將產(chǎn)生的氣體排除干凈,塑件就會(huì)形成氣泡、接縫、表面輪廓不清及填充缺料的成型缺陷,另外氣體受壓,體積縮小會(huì)產(chǎn)生高溫將導(dǎo)致素件局部碳化或燒焦,同時(shí)積存的氣體還會(huì)產(chǎn)生反向壓力而降低充模速度。因此必須考慮排氣問(wèn)題,注射模成型時(shí)排氣通常用如下三種方式進(jìn)行:
a.利用配合間隙排氣
b.在分型面上開(kāi)設(shè)排氣槽排氣
c.利用排氣塞排氣
本塑件可在分型面上開(kāi)設(shè)排氣槽,不必專門開(kāi)設(shè)排氣系統(tǒng)。
1.1.9溫度調(diào)節(jié)系統(tǒng)
無(wú)論什么塑料進(jìn)行注射成型,均有一個(gè)比較適宜的模具溫度范圍,在此模具溫度范圍內(nèi),塑料熔體的流動(dòng)性好,容易充滿型腔,塑件脫模后收縮和翹曲變形小,形狀與尺寸穩(wěn)定,力學(xué)性能以及表面質(zhì)量較高。為了使模溫控制在一理想的范圍內(nèi),現(xiàn)設(shè)計(jì)一模具溫度調(diào)節(jié)系統(tǒng)。由于本次設(shè)計(jì)的塑料PE黏度和流動(dòng)性大,模溫為80~100℃,故無(wú)須設(shè)計(jì)加熱系統(tǒng),只需設(shè)計(jì)冷卻系統(tǒng)以確保合理的模溫。常用的冷卻方法有水冷卻、空氣冷卻和油冷卻,本設(shè)計(jì)采用水冷卻,經(jīng)濟(jì)實(shí)惠。
冷卻系統(tǒng)的設(shè)計(jì)原則與常見(jiàn)冷卻系統(tǒng)的結(jié)構(gòu)
冷卻系統(tǒng)的設(shè)計(jì)原則為:
a) 冷卻水道應(yīng)盡量多
b)冷卻水道至型腔表面距離應(yīng)盡量相等
c)澆口出加強(qiáng)冷卻
d)冷卻水道、入口溫差應(yīng)盡量小
e)冷卻水道應(yīng)沿著塑料收縮的方向設(shè)置
此外,冷卻水道的設(shè)計(jì)還必須盡量避免接近塑件的溶接部位以免產(chǎn)生溶接痕,降低塑件強(qiáng)度;
模具裝配草圖
2.存在問(wèn)題及解決措施
2.1主要問(wèn)題:
首先是Solidworks和ProE三維軟件進(jìn)行電腦三維模擬設(shè)計(jì)件不能很好的使用,因此對(duì)模具不能進(jìn)行仿真模擬,對(duì)模具的質(zhì)量,以及零件的材料選擇等一系列問(wèn)題不能解決。
2.2解決措施:
下功夫?qū)W習(xí)軟件,并找尋相關(guān)模具設(shè)計(jì)書(shū)籍進(jìn)行學(xué)習(xí),經(jīng)常性的向?qū)熀拖嚓P(guān)教師請(qǐng)教。
其次是在模具的設(shè)計(jì)過(guò)程中,對(duì)軟件不能正確進(jìn)行選擇,此環(huán)節(jié)感覺(jué)不是很理解。
解決措施:查閱相關(guān)書(shū)籍,經(jīng)常練習(xí)設(shè)計(jì)軟件,向?qū)熣?qǐng)教學(xué)習(xí)。
3.后期工作安排
3.1完成模具及其附屬零件的三維模型,優(yōu)化模具的整體設(shè)計(jì)以及完成畢業(yè)論文。
3.2 6-8周:運(yùn)用Solidworks或者ProE三維軟件進(jìn)行電腦三維模擬設(shè)計(jì),論證其
可行性;
9-10周:根據(jù)三維模擬設(shè)計(jì)的圖形畫(huà)出二維CAD工程圖紙及工藝卡片;
11-13周:進(jìn)行資料整理并開(kāi)始撰寫(xiě)畢業(yè)論文;
14-15周:進(jìn)行論文和圖紙的修改并準(zhǔn)備畢業(yè)答辯。
指導(dǎo)教師簽字:
年 月 日
注:1. 正文:宋體小四號(hào)字,行距22磅;標(biāo)題:加粗 宋體四號(hào)字
2. 中期報(bào)告由各系集中歸檔保存,不裝訂入冊(cè)。
畢業(yè)設(shè)計(jì)(論文)外文資料翻譯
系 別: 機(jī)電信息系
專 業(yè): 機(jī)械設(shè)計(jì)制造及其自動(dòng)化
班 級(jí):
姓 名:
學(xué) 號(hào):
外文出處: Mechanical Drive
附 件: 1. 原文;2. 譯文
2013年03月
1. 原文
The application of mould
According to the demarcation of the Chinese molding tool industry association, the our country molding tool is basic to is divided into the 10 major type, among them, hurtling to press the mold and plastics to model the mold two major type to have the main part. Press the production value calculation, the our country hurtles to press the mold to have 50% currently or so, the plastics takes shape the mold to about have 20%, pulling the silk mold (tool) to about have 10%, but in the world flourishing industrial country and the plastics of the regions take shape the mold comparison to have all 40%s of molding tool production value generally above.
The country molding tool industry the technique level is not even currently, hanging to compare extremely greatly. From total come up to speak, compare with advanced level of flourishing industrial country and the harbor mesa areas, still have the bigger margin. In the aspects of adopting CAD/CAM/CAE/CAPP etc.Technique design and the manufacturing molding tool, is an applied extensive regardless, still the technique level up all exist the very big margin. At the applied CAD technique design molding tool aspect, had only to adopt the CAD in the design about 10% molding tool, be apart from to lay aside to paint the plank to still is endless of a segment road want to walk; Carry on the molding tool project design and analysis’s to compute the aspect in the applied CAE, also just just start, still was placed in to try out mostly and animation game stage; At the applied CAM technique manufacturing molding tool aspect, on is a manufacturing material that lacks the forerunner to apply, two is an existing craft equipments( include the advanced equipments that near more than 10 in the last years usher in) or because of computing the mechanism type( tiny machine of IBM and it and permit the machine, the HP work station...etc.) dissimilarity, or because of the word stanza difference, operate the speed difference, the anti- electromagnetism interference ability difference...etc., the net rate is lower, only 5% or so molding tool manufacturing equipments just opens this work of exhibition in recent years; Carry on the craft programming aspect in the applied technique of CAPP, be placed in the blank appearance basically, need to be carry on to standardize the foundation work in great quantities; At the molding tool total sex craft technique, if the molding tool models the technique, throws the light technique and gives or get an electric shock to cast into a technique, surface processing technique CAD/ CAM technique application of etc. quickly is just at the our country just start. The calculator lends support to the technical software development, being placed in the lower level, the demand knowledge and empirical backlog still. The molding tool of big and parts of molding tool factories of our country, the car processes the equipments old, expect to be long in the service, the accuracy is bad, the efficiency is low, using up to now and still common of car, plane, drill, whet the equipments to process the molding tool, the hot processing processes to use the salt bath, a type stove still, operation with the worker's experience, the equipments is simple and crude, can consume high. The equipments renews the speed slow-moving, technique reformation, technique progress the strength is not big. Although also ushered in the molding tool of not a few forerunners to process the equipments in recent years, scatter too, or unqualified set, the utilization has or so 25% generally and only, some advanced functions of the equipments also can not get full exertive. Lack the higher molding tool design, the manufacturing craft of the technique character technical personnel and technique worker, lack a talented person of a breadth of knowledge, the knowledge structure layer particularly. Technical personnel within Chinese molding tool profession, have 8% of the employee only ~ 12% is or so and the total technique level of the technical personnel and technique worker are also lower. Was aging with the technique worker's knowledge from the technical personnel of the industry before in 1980, the knowledge structure can't adapt the demand of now; But the 80's is from the personnel of the industry hereafter, the professional knowledge, experience is short of, beginning the ability bad, uneasy heart, do not wish to learn the technique. In recent years the brain drain not only results in talented person quantities ands the character levels descend, and talented person's structure but also appears to break the layer lately, temporary shortage, make the hard exaltation of technique level of the molding tool design, manufacturing.
Near more than 10 in the last years, especially"85", nation is already many to organize the relevant material graduate school, university and college and the steel business enterprises, research and development the molding tool appropriation series steel grow, the appropriation tool that the molding tool appropriation hard quality metal alloy and other molding toolsets process, assistance material etc., also expand. But because of not enough stability of the quantity of the material, the on trial condition that lack the necessity and experiment the data, the specification species less, the steel material and specifications that large molding tool and the special kind molding tools need still have the indentation. Supply in the steel material up, solve the customer piecemeal the supply and demand antinomy that the batch quantity of the dosage and the steel factory produce, didn’t yet get to solve effectively. Moreover, the foreign molding tool steel material is successive to built up the sale net to order in the domestic in recent years, but because of outlet, technique the service prop up weak and the price is higher, foreign exchange balance of accounts system etc. the influence of the factor, expand application currently not much.
The assistance material and the appropriation techniques that molding tool process in recent years although have the expansion application, did not become the mature production technique, still still be placed in to experiment to grope for the stage mostly, if the molding tool surface draws the hot processing technique, molding tool of layer technique, the molding tool surface to lead to the vice- lubrication technique, the molding tool to spread the feeling technique and lubricate the technique, molding tool to go to should dint technique, the molding tool anti- fatigue and antisepsis technique est.It’s didn’t yet become the productivity completely, the alignment commercialize. Some keys, important techniques also still are in need of the protection of the intelligent property right.
The standard piece of the molding tool of the our country produce, just becoming the small scale production at the beginning of 80's, the molding tool standardizes the usage of the degree and standard piece to overlay to face to about have 20%, from can go together with on the market of also only have about 30 species, and be limited by only medium small specification. The standard convex and cave mold, heat flows a component, etc. just started supply, the mold and spare parties produced to supply the outlet, accuracy and quantity is also worse.
The molding tool industry of the country is opposite to fall behind more, still can't call it as an independent profession up to now. The current molding tool of our country produce the business enterprise and can divide the line for the four major type: Professional molding tool factory, the profession produces the outside to provide the molding tool; The molding tool factory of cent or the cars of the product factory, with supply the molding tool that this product factory need is main mission; Three the factory of cent of the molding tool of the business enterprises, it organizes the mode and professional molding tool factories look alike, with small but just for main; The village molding tool business enterprise, with the professional molding tool factory look alike. Among them, the first quantity is most, the molding tool yield about has 70% of the total yield above. The molding tool profession of the country manages the system dispersion. Have 19 big professions section manufacturing and the usage molding tool currently, did not unify the section of management. Only depend the Chinese molding tool industry association orchestration programming, concentrate to offend the pass, across the profession, across the section management the difficulty is a lot of.
The molding tool is feat in win the small scaled business enterprise organization production, but our country the technique reformation investment toward When the big and medium-sized business enterprise tilt to one side, the investment that wins the small scaled molding tool business enterprise cans not get the assurance. Include the molding tool car of the product factory, the factory of cent at inside, the technique reformation after can't very quickly take back it invest, even owing lots of debts, affecting the development. The molding tool is feat in win the small scaled business enterprise organization production, but our country the technique reformation investment toward When the big and medium-sized business enterprise tilt to one side, the investment that wins the small scaled molding tool business enterprise cans not get the assurance. Include the molding tool car of the product factory, the factory of cent at inside, the technique reformation after can't very quickly take back it invest, even owing lots of debts, affecting the development.
Although most molding tool cars of product factory, the cent factory technique powers are strong, the equipments condition is better, the molding tool level that produces is also higher, the equipments utilization is low. Our country molding tool price for long time together it is worth not to moderate, resulting in the phenomenon of the molding tool profession" the economic performance of oneself is small, social performance big"." Standard piece of the not equal to and dry molding tool of the dry molding tool of, the not equal to and dry molding tool of the dry standard piece takes a production of. The stem take a production not equal to process the product with the molding tool of" its type falsely often the phenomenon existence, bruised the molding tool business enterprise (include the molding tool car and divide factory) officers and workers' aggressive sex biggest. This is also the molding tool profession to stay not to live the talented person, youth technical personnel and youth the worker does not wish to learn one of the reasons of the technique
The molding tool industry want last level, the material application is a key. Because choose the material and use the material not appropriate, cause molding tool lead lose efficacy early, account for 45% of expired molding tool about above. At the molding tool material aspect, it is in common use and cold to make the molding tool steel contain CrWMn, Cr12, Cr12MoV and W6Mo5Cr4V2s, the flames fire steel( such as the AUX2, SX105V(7 CrSiMnMoVs)...etc. of Japan; The in common use and new heat make the molding tool steel contain American H13, Sweden QRO80M, QRO90SUPREME etc.;The in common use plastics molding tool prepares the hard steel( such as American P20), time limited efficacy to harden a steel( such as American P21, Japanese NAK55 etc.), hot processing to harden a steel( such as American D2, the Japanese PD613, PD555, Sweden is on winning 136 est.’s of white), the powder molding tool steel( such as Japanese KAD18 and KAS440)...etc. with the steel; Overlay the piece pulls to postpone the in common use HT300, QT60-2, Mo- Cr, the Mo- V iron casting...etc. of mold, the large mold uses the HT250.A precise blunt mold of many works often adopts hard quality metal alloy and hard quality metal alloy YG20 Tec’s of the steel knots. At the molding tool surface processing aspect, its main trend is: From the infiltration one chemical element to diverse plain total, the compound (such as TD method) development; From the general proliferation is to the CVD, PVD, PCVD, ioninfiltration, ion infusion etc, direction development; Adoptable plate the film to have: Tic, Tin, TiCN, TiAlN, CrN, Cr7C3, W2C etc., at the same time hot processing means from atmosphere the hot processing develops toward hot processing of vacuum. Moreover, enhance to the laser currently, the light ion nitrogen turns the technique and electroplate (brush to plate) the antisepsis to enhance etc. the technique also is subjected to the value increasingly.
In the aspects of taking shape the craft, mainly hurtle to press the molding tool function compound to turn, the super take shape, the nicety of takes shape the technique, the plastics mold air assistance to inject the technique and heats to flow a technique, high pressure to inject to take shape the technique etc..On the other hand, make along with the forerunner technical develop continuously and the molding tool profession exaltation of the whole level, appeared some new designs, produce and manage the principle and modes in the molding tool profession. Mainly have in a specific way: Adapt a gentle manufacturing technique that produces the characteristics of molding tool; Create the best management and the team spirit of the performances, the benefit produce; Raise the fast contingency ability abreast engineering, conjecture manufacturing and world nimble manufacturing, network manufacturing new production philosophy of etc.;Adopt the division of labor of an in general use piece to help to make to produce the mode extensively; The orientation can keep on the development and environmental protection request of green design and manufacturing etc..
Along with various new technical and quick developments, the abroad hazes already appeared the molding tool to process the system automatically. This is also the our country target of the farsighted development. Molding tool automatically process system should like and next characteristic: Many reasonable combination of the pedestal tool machine; Have with go to position the tongs or the fixed position dishs; The machine tool, knife that has the integrity has the number to control the database; The number that have the integrity control gentle synchronous system; Have the quantity monitor control system.
In a word, the country molding tool technique had the substantial progress in recent years.
2.譯文
模具的應(yīng)用
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,其中,沖壓模和塑料成型模兩大類占主要部分。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。
? 我國(guó)模具工業(yè)目前技術(shù)水平參差不齊,懸殊較大。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。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。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。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。我國(guó)大部分模具廠、車間的模具加工設(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、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。設(shè)備更新速度緩慢,技術(shù)改造,技術(shù)進(jìn)步力度不大。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。
?? 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。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。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)。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。
?? 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、大專院校和鋼鐵企業(yè),研究和開(kāi)發(fā)模具專用系列鋼種、模具專用硬質(zhì)合金及其他模具加工的專用工具、輔助材料等,并有所推廣。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。在鋼材供應(yīng)上,解決用戶的零星用量與鋼廠的批量生產(chǎn)的供需矛盾,尚未得到有效的解決。另外,國(guó)外模具鋼材近年來(lái)相繼在國(guó)內(nèi)建立了銷售網(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。
?? 模具加工的輔助材料和專用技術(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。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)。
?? 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。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。
?? 我國(guó)的模具工業(yè)相對(duì)較落后,至今仍不能稱其為一個(gè)獨(dú)立的行業(yè)。我國(guó)目前的模具生產(chǎn)企業(yè)可劃分為四大類:專業(yè)模具廠,專業(yè)生產(chǎn)外供模具;產(chǎn)品廠的模具分廠或車間,以供給本產(chǎn)品廠所需的模具為主要任務(wù);三資企業(yè)的模具分廠,其組織模式與專業(yè)模具廠相類似,以小而專為主;鄉(xiāng)鎮(zhèn)模具企業(yè),與專業(yè)模具廠相類似。其中以第一類數(shù)量最多,模具產(chǎn)量約占總產(chǎn)量的70%以上。我國(guó)的模具行業(yè)管理體制分散。目前有19個(gè)大行業(yè)部門制造和使用模具,沒(méi)有統(tǒng)一管理的部門。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),跨部門管理困難很多。
?? 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。包括產(chǎn)品廠的模具車間、分廠在內(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。
?? 雖然大多數(shù)產(chǎn)品廠的模具車間、分廠技術(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。
?? 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?!案赡>叩牟蝗绺赡>邩?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”之類不正常現(xiàn)象存在,極大地挫傷了模具企業(yè)(包括模具車間和分廠)職工的積極性。這也是模具行業(yè)留不住人才,青年技術(shù)人員和青年工人不愿學(xué)技術(shù)的原因之一
模具工業(yè)要上水平,材料應(yīng)用是關(guān)鍵。因選材和用材不當(dāng),致使模具過(guò)早失效,大約占失效模具的45%以上。在模具材料方面,常用冷作模具鋼有CrWMn、Cr12、Cr12MoV和W6Mo5Cr4V2,火焰淬火鋼(如日本的AUX2、SX105V(7CrSiMnMoV)等;常用新型熱作模具鋼有美國(guó)H13、瑞典QRO80M、QRO90SUPREME等;常用塑料模具用鋼有預(yù)硬鋼(如美國(guó)P20)、時(shí)效硬化型鋼(如美國(guó)P21、日本NAK55等)、熱處理硬化型鋼(如美國(guó)D2,日本PD613、PD555、瑞典一勝白136等)、粉末模具鋼(如日本KAD18和KAS440)等;覆蓋件拉延模常用HT300、QT60-2、Mo-Cr、Mo-V鑄鐵等,大型模架用HT250。多工位精密沖模常采用鋼結(jié)硬質(zhì)合金及硬質(zhì)合金YG20等。在模具表面處理方面,其主要趨勢(shì)是:由滲入單一元素向多元素共滲、復(fù)合滲(如TD法)發(fā)展;由一般擴(kuò)散向CVD、PVD、PCVD、離子滲入、離子注入等方向發(fā)展;可采用的鍍膜有:TiC、TiN、TiCN、TiAlN、CrN、Cr7C3、W2C等,同時(shí)熱處理手段由大氣熱處理向真空熱處理發(fā)展。另外,目前對(duì)激光強(qiáng)化、輝光離子氮化技術(shù)及電鍍(刷鍍)防腐強(qiáng)化等技術(shù)也日益受到重視。在成形工藝方面,主要有沖壓模具功能復(fù)合化、超塑性成形、塑性精密成形技術(shù)、塑料模氣體輔助注射技術(shù)及熱流道技術(shù)、高壓注射成形技術(shù)等。另一方面,隨著先進(jìn)制造技術(shù)的不斷發(fā)展和模具行業(yè)整體水平的提高,在模具行業(yè)出現(xiàn)了一些新的設(shè)計(jì)、生產(chǎn)、管理理念與模式。具體主要有:適應(yīng)模具單件生產(chǎn)特點(diǎn)的柔性制造技術(shù);創(chuàng)造最佳管理和效益的團(tuán)隊(duì)精神,精益生產(chǎn);提高快速應(yīng)變能力的并行工程、虛擬制造及全球敏捷制造、網(wǎng)絡(luò)制造等新的生產(chǎn)哲理;廣泛采用標(biāo)準(zhǔn)件通用件的分工協(xié)作生產(chǎn)模式;適應(yīng)可持續(xù)發(fā)展和環(huán)保要求的綠色設(shè)計(jì)與制造等。
隨著各種新技術(shù)的迅速發(fā)展,國(guó)外已出現(xiàn)了模具自動(dòng)加工系統(tǒng)。這也是我國(guó)長(zhǎng)遠(yuǎn)發(fā)展的目標(biāo)。模具自動(dòng)加工系統(tǒng)應(yīng)有如下特征:多臺(tái)機(jī)床合理組合;配有隨行定位夾具或定位盤;有完整的機(jī)具、刀具數(shù)控庫(kù);有完整的數(shù)控柔性同步系統(tǒng);有質(zhì)量監(jiān)測(cè)控制系統(tǒng)。
綜上所述,近年來(lái)我國(guó)模具技術(shù)有了長(zhǎng)足的進(jìn)步。