外文翻譯---塑料壓縮模

1、<p><b>　　附錄：</b></p><p><b>　　英漢互譯</b></p><p><b>　　塑料壓縮模</b></p><p>　　在壓縮成型過(guò)程中，塑料原料是以粉狀或錠料形式放置在加熱的金屬模具型腔中。因?yàn)榉中兔媸撬矫?，上模就垂直下行。閉合模具后，預(yù)成型加壓加熱作用一段

2、時(shí)間。在壓力為2~3t/in和溫度為華氏溫度350的作用下，是塑料呈半液態(tài)，充滿模具型腔。雖然近年來(lái)開(kāi)發(fā)的酚醛樹(shù)脂可在25S內(nèi)塑化，但塑料通常的塑化需要1~15min。最后開(kāi)模取出塑件。如果零件中含有金屬嵌件，應(yīng)在注入塑料前，講嵌件放入型腔定位孔中。錠料在裝入模腔前預(yù)熱出去氣體，增強(qiáng)流動(dòng)性，以便于充滿模具和縮短塑化時(shí)間。電介質(zhì)加熱時(shí)加熱錠料的便利方法。</p><p>　　因?yàn)樗芰鲜侵苯蛹尤肽＞咝颓恢械?，所以壓縮

3、模比其他模塑料工藝的模具簡(jiǎn)單，不需要澆道和澆口，可以節(jié)省原料，因?yàn)榍謇頋驳篮蜐部?，?duì)熱固性塑料來(lái)說(shuō)是極大的浪費(fèi)。用于壓縮模塑的壓力機(jī)通常是垂直液壓機(jī)。較大的壓力機(jī)要求操作者全神貫注地操作；然而，一個(gè)操作者可以同時(shí)操作幾臺(tái)小型壓力機(jī)，因此壓力機(jī)要合理放置以便操作者能夠方便你從一臺(tái)到另一臺(tái)進(jìn)行操作，操作者要保證當(dāng)他再次繞道特定壓力機(jī)前時(shí)，模具恰好準(zhǔn)備開(kāi)模。</p><p>　　熱固性塑料在加熱和加壓作用下固化，這個(gè)特

4、性決定其適合壓縮模和傳遞模。因?yàn)閴嚎s模要交替的加熱和冷卻，所以熱塑性塑料實(shí)際上不是用于壓縮成型。為了使熱塑性塑料之間硬化并從型腔中頂出，就需要將塑件冷卻。</p><p>　　壓縮模的類(lèi)型。 用于壓縮的模具可分為四種基本類(lèi)型，分別是:不溢式壓縮模、擋環(huán)不溢式壓縮模、溢式壓縮模和半溢式壓縮模。在不溢式壓縮模中，柱塞式凸模隨上模進(jìn)入下模模腔成型，因?yàn)橄履](méi)有擋環(huán)或限位裝置，柱塞式凸模繼續(xù)下行以全部壓力施加在塑料上，這

5、樣就成產(chǎn)出具有良好電性能和物理性能的致密塑件。加入模腔的塑料劑量須精確計(jì)量，以為其影響零件的壁厚。擋環(huán)不溢式壓縮模與不溢式壓縮模類(lèi)似，只是在預(yù)定點(diǎn)處增加了擋環(huán)，使柱塞式凸模在預(yù)定點(diǎn)停止運(yùn)動(dòng)，在這種模具中擋環(huán)吸收了原應(yīng)作用在零件上的部分壓力。這種壓縮?？删_控制零件的壁厚，但是塑件密度的變化是相當(dāng)大的。在溢式壓縮模中，溢料會(huì)增加上下模的尺寸。當(dāng)上模對(duì)塑料施壓時(shí)，多余的塑料會(huì)從分型面處溢出。對(duì)溢料進(jìn)一步施壓，他就硬化最后在上模形成飛邊。生產(chǎn)

6、致密塑件通常需要使用的計(jì)算量稍多的原料來(lái)增加壓力。這種類(lèi)型的模具之所以在生產(chǎn)中廣泛采用，是因?yàn)樗雽?duì)比較容易制造，并能夠控制塑件的厚度和致密度，使其更接近要求。半溢式壓縮模是溢式壓縮模和不溢式壓縮模的組合類(lèi)型，除了飛邊外，采用的擋環(huán)可限制上模的移動(dòng)。</p><p><b>　　注塑模重要性</b></p><p>　　1．塑料具有密度小、質(zhì)量輕、比強(qiáng)度大、絕緣性好、

7、介電損耗低、化學(xué)穩(wěn)定性強(qiáng)、成型生產(chǎn)率高和價(jià)格低廉等優(yōu)點(diǎn)，在國(guó)民經(jīng)濟(jì)和人民日常生活的各個(gè)領(lǐng)域得到了日益廣泛的應(yīng)用，早在二十世紀(jì)九十年代初，塑料的年產(chǎn)量按體積計(jì)算已經(jīng)超過(guò)鋼鐵和有色金屬年產(chǎn)量的總和。在機(jī)電（如所謂的黑色家電）、儀表、化工、汽車(chē)和航天航空等領(lǐng)域，塑料已成為金屬的良好代用材料，出現(xiàn)了金屬材料塑料化的趨勢(shì)。</p><p>　　2．以汽車(chē)工業(yè)為例，由于汽車(chē)輕量化、低能耗的發(fā)展要求，汽車(chē)零部件的材料構(gòu)成發(fā)生了

8、明顯的以塑代鋼的變化，目前我國(guó)汽車(chē)塑料占汽車(chē)自重的5%至6%，而國(guó)外已達(dá)13%，根據(jù)專(zhuān)家預(yù)測(cè)，汽車(chē)塑料的單車(chē)用量還將會(huì)進(jìn)一步增加。在現(xiàn)代車(chē)輛上，無(wú)論是外裝飾件、內(nèi)裝飾件，還是功能與結(jié)構(gòu)件，都可以采用塑料材料，外裝飾件有保險(xiǎn)杠、擋泥板、車(chē)輪罩、導(dǎo)流板等；內(nèi)裝飾件有儀表板、車(chē)門(mén)內(nèi)板、副儀表板、雜物箱蓋、座椅、后護(hù)板等；功能與結(jié)構(gòu)件有油箱、散熱器水室、空濾器罩、風(fēng)扇葉片等。據(jù)統(tǒng)計(jì)，我國(guó)2000年汽車(chē)產(chǎn)量200多萬(wàn)輛，車(chē)用塑料達(dá)138萬(wàn)噸。從國(guó)

9、內(nèi)外汽車(chē)塑料應(yīng)用的情況看，汽車(chē)塑料的用量現(xiàn)已成為衡量汽車(chē)生產(chǎn)技術(shù)水平的標(biāo)志之一。</p><p>　　3．作為塑料制件最有效的成型方法之一的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，并且成型周期短，可以一模多腔，生產(chǎn)率高，大批生產(chǎn)時(shí)成本低廉，易于實(shí)現(xiàn)自動(dòng)化生產(chǎn)，因此在塑料加工行業(yè)中占有非常重要的地位。據(jù)統(tǒng)計(jì)，塑料模具約占所有模具（包括金屬模）的38.2%，塑料制品總重量的大約32%是用于

10、注射成型的，80%以上的工程塑料制品都要采用注射成型方式生產(chǎn)。</p><p>　　4．根據(jù)海關(guān)統(tǒng)計(jì)，我國(guó)2000年共進(jìn)口模具9.77億美元，其中塑膠模具共5.5億美元，占56.3%，2001年共進(jìn)口模具11.12億美元，其中塑膠模具共6.16億美元，占55.4%。從品種上來(lái)說(shuō)，進(jìn)口量最大的是塑膠模具。</p><p>　　Compression Molding for Plastics&

11、lt;/p><p>　　In compression molding the palstic material as powder or preforms is placed into a heated steel mold cavity,Since the parting surface is in a horizontal plane ,the upper half of the mold descends ve

12、rtically.It closes the mold cavity and pressures for a predetermined period.A pressure of from 2 to 3 tons square inch and a temperaure at approximately 350F converts the plastic to a semiliquid which flows to all parts

13、of the mold cavity.Usually from 1 to 15 minutes is required for curing,altough a r</p><p>　　Since the plastic material is placed directly into the mold cavity,the mold itself can be simpler than those used f

14、or other molding precesses.Gates and sprues are unnecessary.This also results in a saving in material,because trimmed-off gates and sprues would be a complete loss of the thermosetting plastic.The press require the full

15、attention of one operator.However,several smaller presses can be operated by one operator. The presses are conveniently located so the operator can easilymove from o</p><p>　　the thermosetting plastics which

16、 harden under heat and pressure are suitable for compression molding and transfer molding.It is not practical to moid shermoplastic materials by these methods,since the molds would have to be alternately heated and coole

17、d.In order to harden and eject thermoplastic parts form the mold,cooling would be necessary.</p><p>　　Types of molds for compression molding.The molds used for compression molding are classified into four ba

18、sic types,namely,positive molds,landed positive mold,flash-type molds,and semipositive molds.In a positive mold the plunger on the upper mold enters the lower mold cavity.since there are no lands or stops on the lower di

19、e ,the plunger completely trap the plastic material and descends with full pressure on the charge.A dense part with good electrical and physical properties is produced.The amo</p><p>　　一、Injects the mold the

20、 importance</p><p>　　1. Plastics have the density small, the quality light, the specific tenacity big, the insulating property good, the dielectric loss low, the chemical stability strong, the formation prod

21、uctivity high and the price inexpensive and so on the merits, obtained day by day the widespread application in the national economy and people's daily life each domain, as early as in the beginning of 1990s, the pla

22、stic annual output already surpassed the steel and iron and the non-ferrous metal annual output su</p><p>　　2. Take the automobile industry as the example, as a result of the automobile lightweight, the low

23、energy consumption development request, the automobile spare part material constitution occurred obviously has modelled the band steel the change, at present our country automobile plastic accounts for 5% which the autom

24、obile was self-possessed to 6%, but overseas has reached 13%, forecast according to the expert, the automobile plastic bicycle amount used will also be able further to increase.On m</p><p>　　3. Injection of

25、 a molding formation as plastic workpiece most effective formation methods because may by one time take shape each kind of structure complex, the size precise and has the metal to inlay a product, and the formation cycle

26、 is short, may by mold multi-cavities, the productivity be high, when mass productions the cost is inexpensive, easy to realize the automated production, therefore holds the extremely important status in the plastic proc

27、essing profession.Statistics have indicated,</p><p>　　4. Counts according to the customs, our country in 2000 altogether imported mold 977,000,000 US dollars, in which plastic molding forms altogether 550,00

28、0,000 US dollars, occupied for 56.3%,2001 years altogether to import mold 1,112,000,000 US dollars, in which plastic molding forms altogether 616,000,000 US dollars, accounted for 55.4%.From the variety, the import volum