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XX大學(xué)畢業(yè)設(shè)計(jì)文獻(xiàn)翻譯與原文題目: 相控陣列對(duì)比相控陣列-波束掃描對(duì)比編碼 數(shù)據(jù)采集 學(xué) 院: 測(cè)試與光電工程學(xué)院專(zhuān)業(yè)名稱(chēng): 測(cè)控技術(shù)與儀器班級(jí)學(xué)號(hào): 學(xué)生姓名: 指導(dǎo)教師: 二Oxx 年 四 月 中文翻譯相控陣列對(duì)比相控陣列-波束掃描對(duì)比編碼數(shù)據(jù)采集J. 馬克戴維斯1 與 邁克爾莫爾斯2 2加拿大奧林巴斯無(wú)損檢測(cè) ,加拿大,安大略省,多倫多,電話:(416) 831 442網(wǎng)絡(luò)傳真:(905) 248 -3546,郵箱:M,網(wǎng)址: 1J. 馬克戴維斯, 戴維斯無(wú)損評(píng)價(jià)有限責(zé)任公司., 美國(guó),亞拉巴馬州,伯明翰, 電話:(205) 733 -0404,郵箱:, 網(wǎng)址:摘要本文描述了手動(dòng)和編碼相控陣列設(shè)備之間的不同。僅增加一個(gè)編碼器在技術(shù)上不難實(shí)現(xiàn),那么軟件需求和優(yōu)化的性能變得更為重要。由于規(guī)范或技術(shù)限制,很多無(wú)損檢測(cè)應(yīng)用領(lǐng)域無(wú)法用手動(dòng)(或“波束掃描”)相控陣列裝置來(lái)完成。引言人們有充分的理由相信,相控陣列是現(xiàn)今無(wú)損檢測(cè)方向最熱門(mén)的技術(shù)之一。與傳統(tǒng)的超聲波技術(shù)相比,相控陣列技術(shù)擁有明顯的優(yōu)勢(shì): 速度;對(duì)于焊縫,銹蝕和其他部件,線性(線路掃描)掃描可以大幅地提高掃描速 度(并且因此減少開(kāi)支)。 成像;S-掃描,E-掃描和其他2D及3D成像能提供更好和更容易判斷的缺陷評(píng)估。 靈活性;相控陣列可以對(duì)很多不同類(lèi)型的部件所存在的多種多樣的缺陷進(jìn)行多種掃 描(1)。 數(shù)據(jù)存儲(chǔ);完整的甚或部分的數(shù)據(jù)存儲(chǔ)和顯示能容許更好的缺陷判讀,外加可以用 于存檔目的。 可重復(fù)性;盡管還未曾被第三方實(shí)驗(yàn)證實(shí)過(guò),但使用同樣的帶有相控陣列的設(shè)備和 程序能比使用帶有手動(dòng)超聲波的設(shè)備和程序提供更多的可重復(fù)性結(jié)果。然而,目前市場(chǎng)上可用的相控陣列設(shè)備遠(yuǎn)不止一種。除了早已應(yīng)用了數(shù)十年的一款體積龐大且不方便攜帶的裝置,仍有很多制造商生產(chǎn)便攜式設(shè)備。便攜式相控陣列設(shè)備本身可以劃分成兩類(lèi):手動(dòng)的和編碼的,兩者的區(qū)別和性能很值得注意。本文描述了各種各樣的特征和性能,并且提到了一些可以使用手動(dòng)和編碼設(shè)備的不同類(lèi)型的應(yīng)用領(lǐng)域。相控陣列技術(shù)在綜述里提及,因此本文不會(huì)再詳細(xì)描述。對(duì)物理成分,硬件,軟件和應(yīng)用樣本的廣泛評(píng)估,參見(jiàn)(1)波束掃描相控陣列設(shè)備波束掃描設(shè)備,如手動(dòng)設(shè)備,操作起來(lái)就像也能掃描波束的高檔單晶體設(shè)備一樣。這些設(shè)備使用手動(dòng)握持陣列,與手動(dòng)探測(cè)器使用方式一樣,例如,陣列在焊縫和部件上來(lái)回掃描,操作者通過(guò)屏幕觀察缺陷。主要的不同之處在于觀察者也可以看見(jiàn)S-掃描(參見(jiàn)圖1和圖3示例)或者E-掃描,這些掃描可以輔助缺陷分析??傊?,盡管屏幕顯示可以存儲(chǔ)和報(bào)告,數(shù)據(jù)并不被采集。一些手動(dòng)設(shè)備可以使用時(shí)基數(shù)據(jù)采集來(lái)收集掃描數(shù)據(jù);然而,跟編碼數(shù)據(jù)相比這種數(shù)據(jù)本質(zhì)上是不可靠的,因?yàn)樗鶞y(cè)量的缺陷長(zhǎng)度將會(huì)取決于操作者的掃描速度,且其長(zhǎng)度無(wú)法校準(zhǔn)。時(shí)基掃描,或者波束掃描,尤其不能被諸如美國(guó)工程師協(xié)會(huì)規(guī)范案例2235(2)之類(lèi)的自動(dòng)超聲波測(cè)試規(guī)范所接受。為什么購(gòu)買(mǎi)波束掃描設(shè)備?以下是幾種可能的原因。如果這設(shè)備能每次展現(xiàn)多重A-掃描(如美國(guó)焊接協(xié)會(huì)D1:1檢查標(biāo)準(zhǔn)的45,60和70o-參見(jiàn)參考文獻(xiàn)3),那么潛在地,操作者可以掃描得更快.(當(dāng)然,此設(shè)備標(biāo)準(zhǔn)必須符合美國(guó)工程師協(xié)會(huì)或者其他規(guī)范。)如上所提,在某些情況下2D成像可以提高缺陷評(píng)估和數(shù)據(jù)存儲(chǔ)水平。對(duì)于一些應(yīng)用領(lǐng)域諸如氫致裂紋,一套波束掃描設(shè)備可能足夠了。而且花費(fèi)也比較低。波束掃描設(shè)備實(shí)際上所不能做的就是儲(chǔ)存完整數(shù)據(jù),同時(shí)地執(zhí)行多重功能和進(jìn)行線性掃描。以下均會(huì)涉及到。很多不同的制造商都有波束掃描設(shè)備,圖1顯示的是一個(gè)典型的手動(dòng)相控陣列設(shè)備。圖1:商用波束掃描(或手動(dòng))相控陣列設(shè)備:Olympus 無(wú)損檢測(cè) 全方位掃描M(“手動(dòng)”相控陣列版)。注意其他制造商也生產(chǎn)波束掃描設(shè)備。編碼相控陣列設(shè)備編碼相控陣列設(shè)備能用編碼器收集和儲(chǔ)存掃描數(shù)據(jù),并探測(cè)位置數(shù)據(jù)。雖然這聽(tīng)上去沒(méi)什么大不了-畢竟,往電子設(shè)備上添加一個(gè)編碼器理論上并不難-真正的重點(diǎn)在于其軟件。編碼相控陣列設(shè)備可以收集完整的A-掃描波形數(shù)據(jù),存儲(chǔ)和處理顯示,以提供“頂部,側(cè)邊,底部”視圖,并處理此數(shù)據(jù)。換句話說(shuō),編碼相控陣列設(shè)備是便攜式的,花費(fèi)低的AUT(自動(dòng)超聲波測(cè)試)系統(tǒng),而波束掃描相控陣列設(shè)備是重要的單晶體設(shè)備。掃描的數(shù)據(jù)可以在線下數(shù)據(jù)分析中重復(fù)播放。編碼相控陣列設(shè)備為焊縫等部件提供主要的時(shí)間和成本優(yōu)勢(shì)。圖2a展示了傳統(tǒng)的光柵檢測(cè)過(guò)程,用探測(cè)器向著焊縫來(lái)回移動(dòng)。另一方面,圖2b展示了利用“線性掃描”進(jìn)行的焊縫檢測(cè),例如,在列陣進(jìn)行光柵掃描時(shí)用單程平行掃描焊縫進(jìn)行檢測(cè)。波束掃描相控陣列設(shè)備進(jìn)行光柵掃描(圖2a),而編碼相控陣列設(shè)備也能進(jìn)行線性掃描(圖2b)。圖2a(左),常規(guī)光柵掃描。圖2b(右)線性掃描。線性掃描在速度方面提供了重要優(yōu)勢(shì),或許比單晶體檢測(cè)速度高達(dá)5至10倍。除了采集和顯示所有的缺陷,一些編碼相控陣列設(shè)備能同時(shí)進(jìn)行多方位掃描,例如,它們能在一個(gè)單程掃描中完成編碼要求,此過(guò)程需要陣列在焊縫任意一側(cè)進(jìn)行(參見(jiàn)圖3).更先進(jìn)的設(shè)備還能夠進(jìn)行諸如衍射時(shí)差法超聲檢測(cè)之類(lèi)的額外掃描。圖3:來(lái)自編碼掃描全方位掃描MX的多組屏幕顯示. 注意其他制造商也生產(chǎn)編碼便攜式相控陣列設(shè)備。自然,帶有編碼器性能,數(shù)據(jù)存儲(chǔ),顯示器(影像)再現(xiàn),更多頻道和某些信號(hào)處理功能,這樣的編碼相控陣列設(shè)備相對(duì)于波束掃描相控陣列設(shè)備更昂貴。編碼相控陣列設(shè)備使用者需要更多培訓(xùn)。然而,對(duì)于正確合適的應(yīng)用領(lǐng)域來(lái)說(shuō),編碼數(shù)據(jù)收集是一個(gè)更好更有效的解決方案,而且在大多數(shù)情況下也是唯一的相控陣列解決方案(參加以下樣本應(yīng)用)。圖3 列舉了一個(gè)編碼相控陣列設(shè)備的案例。相控陣列規(guī)范兼容性盡管相控陣列技術(shù)還很新穎,但巨大的市場(chǎng)需求要求相控陣列能與各種各樣的規(guī)范兼容。幸運(yùn)的是,大多數(shù)主流美國(guó)規(guī)范諸如美國(guó)工程師協(xié)會(huì)(4)和美國(guó)焊接協(xié)會(huì)(3)本身就將相控陣列看做一門(mén)技術(shù),但是需要證明被提及的此技術(shù)和程序符合規(guī)范。此證明可以通過(guò)多種途徑進(jìn)行,例如,美國(guó)工程師協(xié)會(huì)第五章第十四條款(5),或者通過(guò)美國(guó)工程師協(xié)會(huì)規(guī)范案例2235(2).檢查編碼數(shù)據(jù)是否符合美國(guó)工程師協(xié)會(huì)規(guī)范案例2235要求是非常重要的。當(dāng)前,可以說(shuō)美國(guó)工程師協(xié)會(huì)是編纂相控陣列技術(shù)規(guī)范的領(lǐng)頭羊。規(guī)范案例2541早已付梓(6),其他規(guī)范還在編纂中。相控陣列一個(gè)值得注意的特征就是即將到來(lái)的校準(zhǔn)要求。美國(guó)工程師協(xié)會(huì)把S-掃描和E掃描解釋為多重波形,每一種都需要校準(zhǔn)符合規(guī)范。美國(guó)工程師協(xié)會(huì)關(guān)于創(chuàng)建相控陣列的新標(biāo)準(zhǔn)慣例采取了同樣的方法:要求全角度校準(zhǔn)增益 (ACG)和時(shí)間校準(zhǔn)增益(TCG)。樣本應(yīng)用波束掃描相控陣列設(shè)備對(duì)需要手動(dòng)操作和成像的應(yīng)用領(lǐng)域大有裨益,典型的是一些工作狀態(tài)中的應(yīng)用。這里,要求的裂縫尺寸或者缺陷表征,和應(yīng)力腐蝕裂紋或者氫致裂紋一樣。很明顯,好的數(shù)據(jù)分析性能和一些成像存儲(chǔ)是有益處的,但大多數(shù)波束掃描設(shè)備能滿(mǎn)足這些最小要求。其他應(yīng)用領(lǐng)域諸如螺栓可以用波束掃描設(shè)備進(jìn)行檢測(cè),但用機(jī)械化和編碼掃描能更好的檢測(cè)。如果設(shè)備能被準(zhǔn)確地校準(zhǔn),焊縫的檢測(cè)可以使用波束掃描,但不如編碼掃描速度快,而且數(shù)據(jù)也不能存儲(chǔ)。航空航天應(yīng)用領(lǐng)域的檢測(cè)視具體情況而定。編碼相控陣列設(shè)備對(duì)任何需要重復(fù)和存儲(chǔ)數(shù)據(jù)的檢測(cè)來(lái)說(shuō)都是很有益處的。這包括了代碼類(lèi)型焊縫檢測(cè),制造,銹蝕測(cè)繪,高速檢測(cè),遠(yuǎn)程應(yīng)用和精準(zhǔn)檢測(cè)(1);基本上任何目前自動(dòng)超聲波測(cè)試所記載的應(yīng)用領(lǐng)域。波束掃描設(shè)備還是編碼相控陣列設(shè)備?答案取決于應(yīng)用領(lǐng)域。對(duì)于一些有限的應(yīng)用,波束掃描設(shè)備可能就足夠了,但是購(gòu)買(mǎi)者需要確認(rèn)此設(shè)備能滿(mǎn)足任何規(guī)范。對(duì)于更先進(jìn)的應(yīng)用,更好的靈活性要求,很明顯編碼相控陣列設(shè)備是很好的選擇。一個(gè)可行的方案就是購(gòu)置一臺(tái)能升級(jí)的設(shè)備,因此操作者可以根據(jù)需要從波束掃描升級(jí)到編碼掃描,或者新手操作者想提升自己的發(fā)展水平。參考文獻(xiàn)1. R/D科技,相控陣列超聲波科技應(yīng)用簡(jiǎn)介-R/D科技參考,出版公司R/D科技 責(zé)任有限公司,2004.1. 美國(guó)工程師協(xié)會(huì) 鍋爐和壓力容器規(guī)范,規(guī)范案例2235-9,2005年10月11日, 應(yīng)用超聲波檢測(cè)代替放射線照相術(shù)。3. 美國(guó)焊接協(xié)會(huì),AWS D1.1,結(jié)構(gòu)焊接規(guī)范,2006.4. 美國(guó)工程師協(xié)會(huì)第五章第四款,美國(guó)工程師協(xié)會(huì) 鍋爐和壓力容器規(guī)范, 2001,2003修訂版,美國(guó)工程師協(xié)會(huì),紐約。5. R.G.Ginzel, E.A.Ginzel, J. Mark Davis, S. Labb and M.D.C.Moles, 美國(guó)工程師協(xié)會(huì)第五章便攜式相控陣列合格證書(shū),2006年美國(guó)工程師協(xié) 會(huì)壓力容器和管道大會(huì)會(huì)議記錄,7月23-27日,2006年;加拿大,哥倫比 亞省,溫哥華,PVP2006-ICPVT11-93566。6. 美國(guó)工程師協(xié)會(huì) 鍋爐和壓力容器規(guī)范,規(guī)范案例2541,2006年1月19日, 第五章使用手動(dòng)相控陣列檢測(cè)。7. 美國(guó)工程師協(xié)會(huì),評(píng)價(jià)相控陣列超聲波檢測(cè)儀器和系統(tǒng)性能特征標(biāo)準(zhǔn)參考, E-2491-06, 美國(guó)測(cè)試和材料協(xié)會(huì),2006年6月。翻譯原文Phased Arrays vs. Phased Arrays-Beam Sweeping vs. Encoded Data CollectionJ. Mark Davis1 and Michael Moles22Olympus NDT Canada, Toronto, ON, Canada, Tel: (416) 8314428, eFax: (905) 248-3546, Email: M, Web site: 1J. Mark Davis, Davis NDE, Inc., Birmingham, AL, USA, Tel: (205) 733-0404, Email: , Web site: Abstract This article describes the differences between manual and encoded phased array units. While merely adding an encoder may not seem technically demanding, the software requirements and improved capabilities are significant. Many NDT applications cannot be performed by manual (or “beam sweeping”) PA units due to code or technical limitations.IntroductionPhased arrays are one of the hot technologies in NDT at this time, with good reason. Compared with conventional ultrasonics, phased arrays offer significant advantages: l Speed; for welds, corrosion and other components, linear (or line scanning) scanning can increase scanning speed (and hence reduce costs) significantly. l Imaging; S-scans, E-scans and other 2D and 3D imaging can give much better and more interpretable defect assessments. l Flexibility; phased arrays can perform a wide variety of scans, for a wide variety of defects on many different types of components (1). l Data storage; full or even partial data storage and display allows better defect interpretation, plus can be used for archive purposes. l Reproducibility; though not demonstrated yet by third party trials, using the same set-up and procedure with phased arrays gives much more reproducible results than with manual ultrasonics.However, there is more than one type of phased array instrument available on the market. Besides the large, non-portable units which have been available for a decade, there are portable units available from several manufacturers. The portable units themselves can be divided into two categories: manual and encoded, and the differences and capabilities are significant. This article describes the various features and capabilities, plus mentions some of the different types of applications that can be performed with manual and encoded units. Phased arrays are quite well referenced in the literature, so this paper will not describe them. For a broad assessment of the physics, hardware, software and sample applications, see (1).The beam sweeping units, i.e. the manual units, operate like upscale monocrystal units that can also sweep the beam. These units use a manually-held array in much the same manner as a manual probe, i.e. the array is rastered toward and away from the weld or component, and the operator watches the screen for defects. The main difference is that the operator also sees an S-scan (see Figures 1 and3 for examples) or E-scan, which can assist in defect analysis. In general, data is not collected, though screen displays can be saved and reported. In some manual units, it is possible to collect scans using time-based data collection; however, this data is inherently unreliable compared with encoded data since the measured defect length will depend on the operators scanning speed, and the lengths are not calibrated. Time-based scanning, or beam sweeping, is specifically not acceptable for AUT codes such as ASME Code Case 2235 (2).Why buy a beam sweeping unit? There are several possible reasons. If the unit can display multiple A-scans at one time (e.g. 45, 60 and 70for AWS D1:1 inspections see ref 3), then potentially the operator can scan faster. (Of course, the unit must be calibrated to the meet the ASME or other Code.) As mentioned above, under some circumstances 2D images can improve defect assessment and data storage. For some applications, e.g. Hydrogen Induced Cracking, a beam sweeping unit maybe adequate. And the cost is lower. What beam sweeping units cannot realistically do is store full data, perform multiple functions simultaneously, and perform linear scanning. These are covered below. Beam sweeping units are available from various manufacturers, and Figure 1 shows a typical manual PA unit.Figure 1: Commercial beam sweeping (or manual) PA unit: Olympus NDTs OmniScan M (the “manual” PA version). Note that other manufacturers also produce beam sweeping units.Encoded PA Units Encoded phased array units have the capability of using an encoder for collecting and storing scan data and probe position data. While this may not sound like a big difference after all, adding an encoder to an electronic unit is theoretically not a big deal the real story is in the software. Encoded PA units can collect full A-scan waveform data, store and manipulate displays to give “top, side, end” views and process this data. In other words, encoded PA units are a portable, low cost AUT (Automated Ultrasonic Testing) system, whereas beam sweeping PA units are glorified monocrystal units. Scanned data can be replayed for offline data analysis.Encoded PA units offer major time and cost advantages for components like welds. Figure 2a shows the traditional raster inspection process, with the probe being moved back and forth towards the weld. Figure 2b, on the other hand, shows weld inspections using “l(fā)inear scanning”, i.e. inspecting using a single pass parallel to the weld while the array performs the rastering. Beam sweeping PA units perform raster scanning (Figure 2a), while encoded PA units can perform linear scanning (Figure 2b) as well.Figure 2a (left), conventional raster scanning. Figure 2b (right) linear scanning.Linear scanning offers significant advantages in speed, maybe up to a factor of five or ten times over monocrystal inspections. Besides collecting and displaying all the defects, some encoded PA units can perform multiple scans simultaneously, i.e. they can fulfill the code requirements in a single pass, with arrayson either side of the weld (see Figure 3). The more advanced units can also perform additional scans like TOFD.Figure 3: Multigroup screen display from OmniScan MX for encoded scanning. Note that other manufacturers also produce encoded portable phased array units.Naturally, with encoder capability, data storage, display reconstruction, more channels and some signal processing, the encoded PA units are more expensive than the beam sweeping PA units. They also require more training. However, for the correct applications, encoded data collection is a much better, more cost-effective solution, and in many cases is the only PA solution (see Sample Applications below). Figure 3 shows an example of an encoded PA unit.PA Code Compatibility Though phased arrays are new, there is a big push from the marketplace to get phased arrays accepted by the various codes. Fortunately, most of the major US codes like ASME (4) and AWS (3) inherently accept phased arrays as a technology, but require demonstration that the proposed technique and procedure fulfill the code. This can be performed through various routes, e.g. ASME Section V Article 14 (5), or through ASME Code Case 2235 (2). It is important to check if encoded data is required, as with ASME CC 2235. At this time, ASME is arguably the leader in codifying phased arrays. Code Case 2541 is already in print (6), and other code cases are in progress. One notable feature for phased arrays are the upcoming calibration requirements. ASME has interpreted an S-scan or an E-scan as multiple waveforms, each of which must be calibrated to Code. The new ASTM standard practice for setting up phased arrays (7) has taken the same approach: full Angle Corrected Gain (ACG) and Time Corrected Gain (TCG) are required.Sample Applications Beam sweeping PA units are good for applications which require manual manipulation and imaging, typically some in-service applications. Here, crack sizing or defect characterization is required, as with stress corrosion cracking or Hydrogen Induced Cracking. Obviously, good data analysis capability and some image storage are beneficial, but most beam sweeping units can fulfill these minimal requirements. Other applications, like bolts, can be performed by beam sweeping units, but these are best performed using mechanized and encoded scanning. Welds can be inspected using beam sweeping, provided the unit can be correctly calibrated, but will not be as fast as encoded scanning, nor will the data be stored. Aerospace applications will depend on the specifics. Encoded PA units will be beneficial for any inspection that requires reproducible, stored data. This includes code-type weld inspections, manufacturing, corrosion mapping, high speed inspections, remote applications, and precision inspections (1); essentially any application that is currently filled by AUT. Beam Sweeping or Encoded PA Units? The answer depends on the applications. For some limited applications, a beam sweeping unit may be adequate, but the purchaser should make sure that t
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