外文資料翻譯=超聲波清洗=2000字符=外文翻譯

1、<p><b>　　外文資料翻譯譯文</b></p><p><b>　　超聲波清洗</b></p><p>　　超聲波清洗技術(shù)是在工業(yè)領(lǐng)域中廣泛應(yīng)用的一種新方法，采用這種技術(shù)可以去除工件表面的磨削、研磨、拋光后殘留的碎屑，清除工件表面殘留的油污，甚至可以除去油漆層。超聲波清洗能夠大范圍的應(yīng)用于工業(yè)零件，大的方面可以到波音 747 飛機

2、的引擎維修，小的方面可以到手表的小零件制作，都有它的用武之地，就目前而言，它以廣泛應(yīng)用電子、精密機械、照明工程、光學、冶金、醫(yī)療儀器設(shè)備等諸多領(lǐng)域。</p><p>　　超聲波清洗技術(shù)在對工業(yè)方面的推動和影響是顯而易見的，要想真正的理解超聲波的價值，我們則需要進一步了解它的原理。</p><p><b>　　超聲波清洗原理</b></p><p&g

3、t;　　超聲波清洗的作用，主要由一種 “空化效應(yīng)”的現(xiàn)象造成，它以每分鐘數(shù)以十億計的空泡向內(nèi)爆裂，而后撞擊到工件的表面，并將工件表面的附著物剝離，分散開來。對于那些手工清洗難以達到的位置，如深孔，死角等，超聲波清洗也可以達到很好的清洗效果，這也是超聲波清洗的優(yōu)點之一。</p><p>　　超聲波清洗常用頻率在 20 kHz到 50 kHz，常用清洗溫度在 50 ℃-80 ℃。</p><p&g

4、t;　　超聲波清洗系統(tǒng)中,空化效應(yīng)是由一系列超聲波換能器將聲波導入清洗槽內(nèi)的清洗液中而產(chǎn)生，這個聲波會傳遍整個清洗槽, 并在液體中產(chǎn)生了波的壓縮和擴張。 在壓縮波時，清洗液中的分子被緊密的壓縮在一起；在擴張波時，分子將被快速的拉開。 擴張的過程十分神奇，以至于分子被裂開時，形成了精微的氣泡，而且氣泡里是局部真空的。當氣泡周圍的壓力變大時，周圍的液體就涌過來，對氣泡施壓并使之破裂。當這個現(xiàn)象發(fā)生時，也就產(chǎn)生了液體的噴射，會使溫度高達 90

5、32華氏度 (約為太陽的溫度)。這個極高的溫度，伴隨著液體噴射的速度，就產(chǎn)生了一個非常強烈的清洗作用。然而，因為氣泡的擴張和爆裂周期是很短暫的，又有伴隨在氣泡外的液體迅速吸收熱量，因此在清洗的過程中不會出現(xiàn)清洗槽和清洗液的過熱現(xiàn)象。</p><p><b>　　影響清洗效果的因素</b></p><p>　　有 7 個主要影響清洗效果的原因:</p>&

6、lt;p><b>　　清洗時間</b></p><p><b>　　清洗液溫度</b></p><p><b>　　清洗液的種類</b></p><p><b>　　4.工件的外形設(shè)計</b></p><p><b>　　5.超聲波頻率&l

7、t;/b></p><p><b>　　6.超聲功率密度</b></p><p><b>　　7.清洗裝夾方式</b></p><p><b>　　清洗時間</b></p><p>　　清洗時間是影響超聲波清洗效果的一個主要因素，它取決于工件的污染程度以及對清潔度的要求，

8、常用的的清洗時間是 2-10 分鐘，只有少數(shù)工件能夠在很短的時間內(nèi)清洗干凈。</p><p>　　實際操作中可能在精細清洗前需要一個預處理的過程，有一些工件需要一道以上的超聲波清洗工序，有些時候，也需要布置超聲波清水漂洗槽去除（前道工序）槽內(nèi)殘留的清洗劑。</p><p><b>　　溫度和清洗劑</b></p><p>　　溫度和清洗劑是兩個

9、緊密相關(guān)的因素。一般來說，在使用水作為清洗劑時，清洗劑的溫度最好在 60 ℃左右 ，一些 PH 較高的溶液則需要更高的清洗溫度。研究化學藥品的 PH 值是一個好的方面，但是深入的討論化學知識并不是這篇文章所要涉及的主要內(nèi)容。因此，下面所列舉的都是一些水基超聲波清洗液的主要組成成分。</p><p>　　水（硬水，軟水，純水，或者蒸餾水）</p><p><b>　　B.酸，或者堿

10、</b></p><p><b>　　C.表面活性劑</b></p><p><b>　　潤濕劑 </b></p><p><b>　　分散劑</b></p><p><b>　　乳化劑</b></p><p><

11、b>　　皂化劑</b></p><p><b>　　D.可選成分</b></p><p><b>　　螯合劑 </b></p><p><b>　　抗化劑</b></p><p><b>　　緩沖劑</b></p><

12、p><b>　　消泡劑</b></p><p>　　應(yīng)該注意的是，在使用化學藥劑時，必須充分考慮以上因素。一些為水射流清洗設(shè)計的化學藥品，包括一些防銹劑，則不適合用于超聲波清洗作業(yè)中。</p><p><b>　　工件的裝夾設(shè)計</b></p><p>　　超聲波清洗的一般程序是：把工件裝入工藝料框，然后再經(jīng)過 3-

13、4 個工序（如：超聲波清洗，噴淋漂洗（可選），浸泡漂洗，干燥），在清洗料框時，有時超聲波輻射會被工件遮擋住。所以，大多數(shù)超聲波清洗設(shè)備都被設(shè)計為專門用途，在設(shè)計階段，要重點考慮超聲波換能器的布置方式，可以采用底置或側(cè)置。對于自動聲波清洗設(shè)備，必須要準確的布置換能器以確保清洗效果的一致性。一些工件對超聲波清洗以及所用到的其他工序需要采取不同的裝夾方式。一些工件需要在清洗過程中旋轉(zhuǎn)或者微動以保證清洗的順利進行。</p><

14、;p><b>　　超聲波輸出頻率 </b></p><p>　　目前大多數(shù)工業(yè)清洗應(yīng)用中采用較低的工作頻率 40 kHz作為基礎(chǔ)頻率 。例如 20-25 kHz , 常用于超聲波空化腐蝕較少的金屬，或者極大阻礙或吸收超聲波傳播的場合。</p><p>　　功率密度（每加侖的瓦數(shù)）（ 1 加侖 = 3.8 升 ）</p><p>　　一般來

15、講，小的工件需要較高的功率密度以達到所要求的清洗效果。大多數(shù)工業(yè)清洗設(shè)備需要的功率密度在 50-100 瓦 / 加侖。不過，容積超過 50 加侖 的水槽，通常只需要大約 20 瓦 / 每加侖的功率密度，因為超聲波系統(tǒng)水箱的容積越大，一般需要的功率密度呈下降趨勢。</p><p><b>　　工件的清洗載入方式</b></p><p>　　在清洗設(shè)備的設(shè)計階段，必須要充

16、分考慮工件清洗時的載入方式。一些較大的工件、內(nèi)部比較難以清洗的工件（例如一些鑄造件），清洗時的原則是:只能載入重量是清洗液的一半的工件清洗，例如，在 5 加侖 的水中 ( 大約 40 磅 ) ，一次只能載入 20 磅 的工件清洗，在大多數(shù)實踐中，分兩次載入較少的工件清洗比一次載入較多的工件清洗效果要好得多。</p><p>　　在設(shè)計一個高品質(zhì)的超聲波清洗系統(tǒng)時，以上所述的相關(guān)因素需要綜合考慮，忽視了某一項都可能

17、使清洗系統(tǒng)造成不良的反應(yīng)。</p><p>　　Ultrasonic Cleaning</p><p>　　Ultrasonic cleaning is a good fit for a wide range of applications, from removing swarf and grinding and polishing residue to treating parts c

18、overed in oil, grease, or layers of paint. Ultrasonics can be used to clean miniature watch parts or to support the overhaul of jumbo jet engines. And from an industry perspective, the fields of electrotechnics, precisio

19、n mechanics and light engineering, optics, metal processing, and medical equipment have proven particularly receptive to the ultrasonic co</p><p>　　So the impact of ultrasonic cleaning is clearly recognizabl

20、e. But to truly understand the value of ultrasonics, one must understand how ultrasonic cleaners really work.</p><p>　　Ultrasonic Cleaning Explained</p><p>　　The cleansing effect of ultrasound i

21、s the product of a phenomenon called cavitation. Billions of minute gas bubbles implode, causing shock waves that undermine dirt and blast it off a part’s surface. One of the key advantages of this process is that it all

22、ows users to clean part surfaces that are completely inaccessible to a manual cleaning process.</p><p>　　Ultrasound frequencies generally range between 20 kilohertz and 50 kilohertz, depending on application

23、 requirements. Ultrasonic cleaning is typically performed at temperatures between 122 F and 176 F .</p><p>　　In an ultrasonic cleaning system, cavitation is produced by introducing sound waves into a cleanin

24、g liquid by means of a series of transducers mounted to a cleaning tank. The sound travels throughout the tank and creates waves of compression and expansion in the liquid. In the compression wave, the molecules of the c

25、leaning liquid are compressed together tightly. Conversely, in the expansion wave, the molecules are pulled apart rapidly. The expansion is so dramatic that the molecules are ripped </p><p>　　Secrets to Ultr

26、asonic Success</p><p>　　There are seven major concerns related to successful ultrasonic cleaning:</p><p><b>　　1. Time </b></p><p>　　2. Temperature </p><p>　

27、　3. Chemistry </p><p>　　4. Part Fixture Design</p><p>　　5. Ultrasonic Output Frequency</p><p>　　6. Watts Per Gallon </p><p>　　7. Loading </p><p>　　TimeClea

28、ning times can vary tremendously in an ultrasonic process, depending largely on how dirty the part is and how clean is clean. A normal trial period is two to 10 minutes, since very few parts are sufficiently clean in a s

29、horter period of time.</p><p>　　Precleaning may be required to remove gross contamination or to chemically prepare the parts for a final clean. Some applications require more than one ultrasonic treatment to

30、 complete the required cleaning. Ultrasonic rinsing may also be required in some cases to more thoroughly remove wash chemicals.</p><p>　　Temperature & ChemistryTemperature and chemistry are closely rela

31、ted. Generally, ultrasonic cleaning in an aqueous solution is optimized at 140 F . Some high pH solutions require higher temperatures. The chemical pH is a good place to start; but a thorough examination of chemistry is

32、beyond the scope of this article.</p><p>　　In brief, the following should be considered the main components of aqueous ultrasonic cleaning chemistry:</p><p>　　A. Water (hard, soft, DI, or distil

33、led) </p><p><b>　　B. pH </b></p><p>　　C. Surfactants </p><p>　　Wetting agents </p><p>　　Dispersants </p><p>　　Emulsifiers </p><p>

34、　　Saponifiers </p><p>　　D. Optional Ingredients </p><p>　　Sequestrants</p><p>　　Inhibitors </p><p>　　Buffering agents </p><p>　　Defoamers </p><p

35、>　　The chemical formulation must consider all of the above characteristics. Some chemicals designed for spray cleaning — or that include rust inhibitors — are not suitable for ultrasonic cleaning.</p><p>

36、　　Part Fixture DesignThe procedure for ultrasonic cleaning is generally as follows: Put parts in basket and place basket through three or four process steps (i.e., ultrasonic wash, spray rinse (optional), immersion rinse

37、, dry). Some parts loaded in baskets can mask or shadow from the radiated surface of the ultrasonic transducers. Most ultrasonic cleaning systems are designed for specific applications. Bottom-mounted transducers or side

38、-mounted transducers are important considerations during the p</p><p>　　Ultrasonic Output FrequencyThe majority of the ultrasonic cleaning that is done in industrial applications today uses 40 kHz as a base

39、frequency. Lower frequencies, such as 20-25 kHz, are used for large masses of metal where ultrasonic erosion is of little consequence. The large mass dampens or absorbs a great amount of the ultrasonic cleaning power.<

40、;/p><p>　　WattsPer GallonIn general, smaller parts require higher watts per gallon to achieve the desired level of cleanliness. Most industrial ultrasonic cleaning systems use watt density from 50 to 100 watts

41、per gallon. However, tanks over 50 gallons usually require only about 20 watts per gallon because ultrasonic processes traditionally have shown diminishing returns in large tanks sizes.</p><p>　　LoadingLoadi

42、ng of the parts to be cleaned must be considered when developing an ultrasonic cleaning process. A large dense mass, for example, prevents internal surfaces from being thoroughly cleaned (i.e., metal castings). A rule of

43、 thumb is that the load by weight should be less than the weight of half the water volume. So, for example, in five gallons (approximately 40 lbs .) of water, the maximum workload should be less than 20 lbs . In some cas

44、es, it is better to ultrasonically clean two sma</p><p>　　Each of the factors outlined here must be considered when specifying an ultrasonic application to ensure a high level of cleaning success. Neglecting