版權(quán)說明:本文檔由用戶提供并上傳,收益歸屬內(nèi)容提供方,若內(nèi)容存在侵權(quán),請進(jìn)行舉報或認(rèn)領(lǐng)
文檔簡介
1、<p><b> 注塑成型</b></p><p> 在注塑成型中,塑料顆??恐辛牧隙愤M(jìn)入加熱桶。當(dāng)螺桿柱塞將塑料顆粒緩慢向前推進(jìn),塑膠被推進(jìn)能使之溶化的加熱腔。由于柱塞向前運(yùn)動,溶化塑料壓迫通過正對著模具的噴嘴、澆口和熱道系統(tǒng)進(jìn)入型腔。模具保持冷卻,因此模具一旦被填滿,塑料就開始凝固。</p><p> 對于注塑周期開始,四個標(biāo)準(zhǔn)必須滿足:模具打開
2、,推桿收回,開始注射,傳輸向前。當(dāng)這標(biāo)準(zhǔn)都達(dá)到了,注射周期伴隨著模具的閉合開始。這個過程通常要求盡快完成,臨近結(jié)束時慢慢靠近。模具工作要求低速和低氣壓閉合。它通常在模具導(dǎo)桿開始運(yùn)作前,必須正確設(shè)計位置以防止意外損壞模具。當(dāng)模具與伴觸鉗噸位接觸,隨即溶化塑料本注射入模具。材料通過澆口套進(jìn)入模具,之后流道系統(tǒng)將材料傳遞到澆口。澆口引導(dǎo)材料進(jìn)入模具型腔從而形成所要的零件。這個注射的過程通常有速率的控制。</p><p>
3、; 當(dāng)零件差不多充滿型腔時,注射控制從速率控制轉(zhuǎn)向壓力控制,稱為保壓周期。壓力必須保持直到澆口處凝固從而避免熔融塑料的回流。冷卻時間主要取決于零件的壁厚和材料。注射產(chǎn)品通常要求快速冷卻。水通常經(jīng)過水道進(jìn)入模具加快冷卻速度。在冷卻周期后部分,澆口已經(jīng)凝固,塑化發(fā)生。</p><p> 塑化是熔融塑料好人準(zhǔn)備下次注射的一個過程。材料在料斗通過料斗頸部開始進(jìn)入料筒。料斗頸部必須保持冷卻以防止因為料筒太熱而導(dǎo)致塑料顆
4、粒熔在一起。料筒包含一個用于剪切熔料的螺桿,它由三部分組成。第一部分是流入部分,它推動塑料小球向前運(yùn)動并要求料筒溫度高使得塑料小球軟化。螺紋深度一致且最深的就在這一部分。下一部分是轉(zhuǎn)動部分,這一部分負(fù)責(zé)通過剪切熔融材料。在這一部分,螺紋深度不斷地減少,壓縮熔料。最后一部分是計量剖面,這一部分螺紋深度淺薄,提高熔融的質(zhì)量和顏色的分布。在螺桿前面的是能夠讓螺桿同時作為擠出機(jī)和柱塞的止回閥。當(dāng)注射螺桿倒退以便形成注射,止會裝置引導(dǎo)材料流到螺桿
5、的前面行成一熔料池或注射。在注射中,止回裝置防止注射流回螺桿部分。 </p><p> 當(dāng)注射開始建立且冷卻時間結(jié)束,模具打開。模具打開必須遵守慢——快——慢。模具必須慢慢打開以釋放在注射過程中產(chǎn)生的真空以防止零件停留在定模上。因為推出系統(tǒng)的移動在定模上,所以要盡量避免這種情況。然后盡快地打開模具,如果沒有使用機(jī)器手,模具只需要打開夠零件移出的距離。即將結(jié)束時必須減速以補(bǔ)償模具沖量。如果不放慢機(jī)器速度就不能準(zhǔn)確
6、定位,產(chǎn)生的沖擊可能損壞機(jī)器。當(dāng)模具打開時,推桿向前運(yùn)動,推動零件。當(dāng)推桿返回,所有的成型循環(huán)標(biāo)準(zhǔn)都達(dá)到,那么下個成型周期可以開始。</p><p> 基本注射周期如下:合?!⑸溲b置移動——注入塑料——測定——運(yùn)輸返回——開模——推出零件。有些機(jī)器是由電動機(jī)代替液壓機(jī)或二者兼而有之。冷卻水道,協(xié)助冷卻模具和塑料加熱固化。冷卻不當(dāng)可導(dǎo)致扭曲成型。當(dāng)模具打開,零件在模具內(nèi)部的推桿的協(xié)助下被推開,成型周期完成。&
7、lt;/p><p> 樹脂或者注坯模型的原材料,通常以藥丸或粒子形式被提供。樹脂小球涌入有大漏底的料斗中,料斗與圓柱形的水平料桶相連接。在料筒內(nèi)的螺桿由電機(jī)轉(zhuǎn)動,原料顆粒將螺桿的螺紋槽填滿。螺桿的螺紋深度往模具的一端減少,壓縮已加熱的塑料。當(dāng)螺桿轉(zhuǎn)動,塑料顆粒由螺桿帶動前進(jìn),并且承受溶化所需要的極端的壓力和摩擦。在溶化的過程期間,料筒的外部附有電熱絲以協(xié)助熱化和溫度控制。</p><p>
8、 通過流道進(jìn)入模具型腔的塑料也會凝固,形成一個附加的框架。這個由熔融的殘料構(gòu)成的框架,是溶化的樹脂從料斗流經(jīng)型腔的主通道,它與模具的開合方向平行;而與開合方向垂直的分流道,用于將熔融塑料傳遞到澆口。澆口和流道系統(tǒng)能夠被剪斷、扭斷和重復(fù)利用,有時在線條機(jī)構(gòu)旁邊被顆?;?。有些模具被設(shè)計成零件自動脫離的形式。</p><p> ·我國塑料加工企業(yè)星羅其布,遍布全國各地,設(shè)備的技術(shù)水平參差不齊,大多數(shù)加工企業(yè)
9、的設(shè)備都需要技術(shù)改造。這幾年來,我國塑機(jī)行業(yè)的技術(shù)進(jìn)步十分顯著,尤其是注塑機(jī)的技術(shù)水平與國外名牌產(chǎn)品的差距大大縮小,在控制水平、產(chǎn)品內(nèi)部質(zhì)量和外觀造型等方面均取得顯著改觀。選擇國產(chǎn)設(shè)備,以較小的投入,同樣也能生產(chǎn)出與進(jìn)口設(shè)備質(zhì)量相當(dāng)?shù)漠a(chǎn)品。這些為企業(yè)的技術(shù)改造創(chuàng)造了條件。</p><p> 為加強(qiáng)塑料機(jī)械的使用、維護(hù)和管理工作,我國有關(guān)部門已制訂了有關(guān)標(biāo)準(zhǔn)和實(shí)施細(xì)則,要求各設(shè)備管理部門和生產(chǎn)企業(yè)對設(shè)備的管理和使
10、用做到“科學(xué)管理、正確使用、合理潤滑、精心維護(hù)、定期保養(yǎng)、計劃檢修,提高設(shè)備完好率,使設(shè)備經(jīng)常處于良好態(tài)。</p><p> 塑料注射成型技術(shù)是根據(jù)壓鑄原理從十九世紀(jì)末二十世紀(jì)初發(fā)展起來的,是目前塑料加工中最普遍采用的方法之一。該法適用于全部熱塑性塑料和部分熱固性塑料(約占塑料總量的1/3) </p><p> 注射系統(tǒng)是注塑機(jī)的心臟部分,其作用是保證定時、定量地把物料加熱塑化,然后以
11、一定的壓力和盡快的速度把相當(dāng)于一次注射量的熔融塑料注入模腔內(nèi),注射完畢還要有一段保壓時間以向模腔內(nèi)補(bǔ)充一部分因冷卻而收縮的熔料,使制品密實(shí)和防止模腔內(nèi)物料反流。因此,注射裝置必須保證塑料均勻塑化,并有足夠的注射壓力和保壓壓力。能滿足這些要求的注射裝置主要有柱塞式、柱塞—螺桿式、螺桿式等。 </p><p><b> 注:</b></p><p><b>
12、 注塑機(jī)的動作程序:</b></p><p> 噴嘴前進(jìn)→注射→保壓→預(yù)塑→倒縮→噴嘴后退→冷卻→開?!敵觥酸槨_門→關(guān)門→合?!鷩娮烨斑M(jìn)</p><p> 注塑機(jī)操作項目:注塑機(jī)操作項目包括控制鍵盤操作、電器控制柜操作和液壓系統(tǒng)操作三個方面。分別進(jìn)行注射過程動作、加料動作、注射壓力、注射速度、頂出型式的選擇,料筒各段溫度及電流、電壓的監(jiān)控,注射壓力和背壓壓力的調(diào)節(jié)等&
13、lt;/p><p> Injection molding</p><p> In injection molding, plastic particles by neutral from hopper into heat barrel. When screw plunger will plastic particles slow advance, plastic is advancing
14、can make the melting of heating chamber. Because the plunger moving forward, melting plastic oppression by opposite the mould of nozzle, sprue and hot word systems into a cavity. Mould keep cooling, thus mould once be fi
15、lled, plastic began to solidify.</p><p> For injection molding cycle begins, the four standard must satisfy: mold open, push rod back, start injection, transmission forward. When this standard has achieved,
16、 injection cycle with mold closed began. The process is usually required to quickly finish, near the end of the approaching. Mould work requirements low and depression closure. It is usually in the mold guide bar begins
17、operation before, we must properly design position to prevent accidental damage mold. When the companion touch clam</p><p> If parts are almost full of cavity, injection control from rate controlling steeri
18、ng pressure control, called pressure-keeping cycle. Pressure must be kept until sprue place to avoid molten plastic solidification of backflow. The cooling time mainly depends on the part of wall thickness and materials.
19、 Injection products usually require fast cooling. Water usually through waterway into the mold speed up the cooling speed. In cooling cycle after part, sprue has solidification, plasticizing happen.</p><p>
20、 Plasticizing is molten plastic injection of a good man and prepare the next process. Materials in the hopper through hopper neck began to enter a nitrogen-treated barrel. Hopper neck must keep cooling to prevent because
21、 nitrogen-treated barrel too hot to plastic particles melt together. Contains a nitrogen-treated barrel for shear molten material screw, it consists of three parts. The first part is inflows part, which promotes plastic
22、ball forward movement and requirements for stove temperature </p><p> When injected began to establish and cooling time end, mould open. Mould open must abide by the slow - fast - slow. Molds must slowly op
23、ened to release the injection produces in the process of vacuum to prevent parts stay in fixed modules. Because of mobile launch system in fixed mode, so try to avoid this kind of circumstance. Then quickly open mold, if
24、 not using machine hand, mould only need to open enough to remove the parts distance. End must slow down to compensate mould impulse. If you don</p><p> Basic injection cycle as follows: shut the mould -- -
25、 injection plastic injection device that moves back -- -- -- determination transport cavity -- introducing parts. Some machines is from motor instead of hydraulic press or both. The cooling channels, assist cooling mould
26、 and plastic heat cure. Cooling undeserved can cause distortion forming. When the mould parts in the mold open, with the assistance of the internal putts burst open, and shape cycle completed.</p><p> Resin
27、 or note billet model of the raw material, usually in pills or particle forms are provided. Resin balls into a great leakage at the bottom of the hopper, hopper and cylindrical level material barrel connections. In a nit
28、rogen-treated barrel within the screw by motor rotation, raw materials particles will screw thread slot fill. The screw thread depth to one end of the mould has heating decreases, compression plastic. When screw rotation
29、, plastic particles by screw drive advance, and bear me</p><p> Through the flow into the mold cavity plastic will solidify, forming an additional framework. This by molten residual material composition of
30、the framework and melting resin flows from hopper wushan, it and cavity mould protrusion parallel, But with the direction of vertical shunt compresses the tao, used for molten plastic relay to the gate. Gate and runner s
31、ystem can be cut, twisting and reuse, sometimes in line - beside. By institutions Some mould are designed to automatically from parts of t</p><p> China plastics processing enterprise star ROM the cloth, th
32、roughout the country, the technology of equipment level irregular, most processing enterprises equipment all need technical reformation. In recent years, our country plastic machinery industry technology progress and rem
33、arkable, especially injection technology level and foreign famous brand product in the gap considerably reduced and internal control level, product quality and appearance shape, etc are achieved significant change. Choos
34、e</p><p> In order to strengthen the plastic machinery, the use, maintenance and management, China's relevant departments have established related standards and implementation rules, and required the eq
35、uipment management departments and production enterprise for equipment management and use achieves "scientific management, correctly use and reasonable lubrication, elaborate maintenance, maintenance regularly, plan
36、 maintenance, improve equipment intact rate, make the equipment frequently in good condition.</p><p> Plastic injection molding technology is based on the principle of die-casting from 19th century and the
37、early twentieth century developed, is currently the most widely used processing plastic one way. The method applies to all thermoplastics and parts of thermosetting plastic (occupy plastic volume 1/3)</p><p>
38、; Injection system is the heart of injection molding machine, its effect is guaranteed timing, quantitatively the material plastication heating, and then taking certain pressure and speed of the equivalent as soon as po
39、ssible an injection quantity of molten plastic injection mold cavity, even for a complete injection time pressure-keeping to mold cavity supplement for cooling and contraction of the cladding material, make the products
40、close-grained and prevent mold cavity material reverse flow. Th</p><p><b> Note:</b></p><p> Injection action program:</p><p> Nozzle forward - injection - pressure-k
41、eeping - plastic shrinkage furnace-rough pour gets back - cooling furnace-rough furnace-rough nozzle open mold - ejection - back needle - open - closed - shut the mould - nozzle forward</p><p> Injection mo
42、lding machine operation projects: injection molding machine operation project including control keyboard, electric contorol operation and hydraulic system operating three aspects. Separately injection process action, cha
43、rging action, injection pressure and injection velocity, ejector type selection, nitrogen-treated barrel paragraphs temperature and current and voltage monitoring, injection pressure and back pressure adjustment, etc<
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(lián)系上傳者。文件的所有權(quán)益歸上傳用戶所有。
- 3. 本站RAR壓縮包中若帶圖紙,網(wǎng)頁內(nèi)容里面會有圖紙預(yù)覽,若沒有圖紙預(yù)覽就沒有圖紙。
- 4. 未經(jīng)權(quán)益所有人同意不得將文件中的內(nèi)容挪作商業(yè)或盈利用途。
- 5. 眾賞文庫僅提供信息存儲空間,僅對用戶上傳內(nèi)容的表現(xiàn)方式做保護(hù)處理,對用戶上傳分享的文檔內(nèi)容本身不做任何修改或編輯,并不能對任何下載內(nèi)容負(fù)責(zé)。
- 6. 下載文件中如有侵權(quán)或不適當(dāng)內(nèi)容,請與我們聯(lián)系,我們立即糾正。
- 7. 本站不保證下載資源的準(zhǔn)確性、安全性和完整性, 同時也不承擔(dān)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
- 注塑成型的模具設(shè)計外文翻譯
- 模具專業(yè)畢業(yè)設(shè)計外文翻譯--注塑成型的智能模具設(shè)計工具
- 模具專業(yè)畢業(yè)設(shè)計外文翻譯--注塑成型的智能模具設(shè)計工具
- 模具專業(yè)畢業(yè)設(shè)計外文翻譯--注塑成型的智能模具設(shè)計工具
- 桶蓋注塑成型工藝與模具設(shè)計
- 后蓋注塑成型工藝及模具設(shè)計
- 模具專業(yè)畢業(yè)設(shè)計外文翻譯--注塑成型的智能模具設(shè)計工具.doc
- 模具專業(yè)畢業(yè)設(shè)計外文翻譯--注塑成型的智能模具設(shè)計工具.doc
- 外文翻譯-注塑注塑成型工藝
- ?。『笊w注塑成型工藝及模具設(shè)計.doc
- 支撐塊注塑成型工藝及模具設(shè)計
- 航空杯注塑成型工藝及模具設(shè)計
- 塑料成型工藝與模具設(shè)計課程設(shè)計--外殼注塑成型模具設(shè)計
- 塑料儀表蓋注塑成型工藝及模具設(shè)計
- 電風(fēng)扇上蓋注塑成型模具設(shè)計
- 電風(fēng)扇上蓋注塑成型模具設(shè)計
- 電風(fēng)扇上蓋注塑成型模具設(shè)計
- 電風(fēng)扇上蓋注塑成型模具設(shè)計
- 外文翻譯--注塑成型機(jī)
- 電風(fēng)扇上蓋注塑成型模具設(shè)計
評論
0/150
提交評論