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1、<p><b>  附 錄</b></p><p>  附錄A 外文文獻(xiàn)原文</p><p>  Ultra-high hydraulic angle O-ring seal</p><p>  the experimental study</p><p>  Abstract :</p>&l

2、t;p>  Nitrile rubber O-ring EHV end Kok containers sealed imposed on containers so high hydraulic seal experimental series. The results show that angle enclosed structure, as well as O-ring compression rate, diameter,

3、 enclosed space, rubber hardness, The sealing surface roughness and seal the form and position tolerances, and other relevant factors reasonable match, strict control, the use of ordinary O-ring can be achieved 138MPa ul

4、trahigh static hydraulic seal.</p><p>  Keywords : EHV static O-ring seal</p><p>  Along with the rapid modern industrial development, UHP increasingly widespread use of the ultrahigh-pressure k

5、illing Hill, super-high-speed refrigeration, Expanded food industry, supercritical fluid extraction, low-salt treatment, Expanded room temperature and high pressure compression fermentation and other typical applications

6、. Such equipment is produced by the many advantages of increasing people's attention. If UHP food production is instantaneous pressure, role uniform, safe operation and </p><p>  However, China's cur

7、rent UHP food production industries badly need to improve the level of equipment, can produce economic, Energy-saving, safe and efficient handling equipment constrains EHV food processing technology marketing major bottl

8、eneck. Among them, how to create economic EHV containers and ensure that the high pressure seal containers is particularly difficult lie. UHV equipment can operate normally sealed to a large extent depends on the integri

9、ty of the structure. High pressure seali</p><p>  1 O-ring seal from the Principle</p><p>  1) state preload </p><p>  O-ring sealed site after its general section by a certain amou

10、nt of compression, as O-rings have good flexibility, the interface will have a certain degree of contact pressure, thus achieving preload under seal. </p><p><b>  2) state </b></p><p&g

11、t;  When the sealed chamber filled with hydraulic media, the role of media pressure, the O-ring to shift the low-pressure side, and the seal gap closed to live. With the increase of media pressure, the contact pressure h

12、as also been increasing, the peak is always greater than the fluid pressure. This will guarantee that the O-ring seal the sealing function, reflects the O-ring seal the ability to automatically sealed. Experience has sho

13、wn that for ordinary rubber materials, generally 13 × 105Pa than</p><p>  2 the main parameters of Seal</p><p>  O-ring seal effects and compression rate, diameter, enclosed space, rubber h

14、ardness, The sealing surface roughness and seal the form and position tolerances, and other factors are closely related. The impact of O-ring seal properties of various factors, as long as the parameters of a design will

15、 reduce the unreasonable results sealed, even result in seal failure. Now, therefore discuss the impact of specific factors to determine the value . </p><p>  1)compression rate</p><p>  After t

16、he O-shape link loads the seal spot, its section generally receives a quota the compression, because the O shape link has the good elasticity, docking touches personally meets has the certain contact pressure, thus reali

17、zes under the pre- tight condition seal.</p><p>  2) active status</p><p>  After the sealed chamber sufficiently enters the hydraulic pressure medium, in under the medium pressure function, the

18、 O shape link carries over a low pressure side, seals up the seal gap. Along with the medium pressure increase, the contact pressure also along with it increase, its peak value always is bigger than the fluid medium pres

19、sure. This has guaranteed the O shape packing ring seal function, also has reflected the O shape packing ring automatic sealing ability. The experience indicated </p><p>  3) seal gap</p><p>  O

20、-ring gap in the high-pressure easily deformed easily be squeezed into the sealed space in order to cause damage, it is necessary to the O-ring seal gap to be strictly controlled. To prevent O-ring extrusion occurred, an

21、d to take into account the difficulty of installing and dismantling, The experimental space for the sealing of 0.1mm.</p><p>  3 experimental devices and airtight structure </p><p>  1) hardness

22、 </p><p>  Elastic modulus small O-ring, the maximum contact stress small, extrusion capacity, easy to destroy. So when a high pressure, high hardness should use the O-ring. In this experiment the O-ring har

23、dness IRHD (International Rubber Hardness levels), 80 ± 5.5) sealing surface roughness Seal the surface roughness is sealing technique to measure an important indicator. If the sealing surface Department has manufac

24、turing defects or vertical scratch, it is very easy to seal leakage media. "Ultrahigh Pre</p><p>  2) seals the form and position tolerances secret </p><p>  Sealed cylindrical surface of r

25、oundness, cylindricity tolerance by eight precision selection Hole-face vertical axis of tolerance by seven precision selection. </p><p>  4 experiment </p><p>  (1) O-ring uniform surface coati

26、ng small grease. Cover and Arbors will use double-headed stud connection, and O-ring installed mandrels, Bolt pallets used to connect to the mandrels to compress O-ring; </p><p>  (2) high-pressure pipe asse

27、mbly, and the small joints nut nuts, Nut will joints and hydraulic media entrance of the threaded connection; </p><p>  (3) under the pallets, containers and with the end caps on the map by a plate placed. P

28、ress access to power, two plate compactor next two pad; (4) access to power, preheat 5 minutes, Pressure relief valve rotation. 10 MPa to the differential pressure, pressure per-Level 5 minutes to observe any leakage; &l

29、t;/p><p>  (5) Records Expander pressure on the indicator values and the hydraulic fluid leakage. </p><p>  several experiments show that, as long as a reasonable choice and strictly control the im

30、pact of the sealing performance of the main factors figure, Individual use of ordinary O-ring seal structure cone 138MPa can achieve a reliable seal; As laboratory equipment constraints, the experiment is just 138MPa hyd

31、raulic seal, O-ring seals that there is a potential to be tapped. </p><p>  O-ring seal structure of cone-shaped O-ring seal and the corresponding surface of the manufacture of certain deviation compensation

32、, This reduces the manufacturing of precision requirements, this seal structure should be promoted; O-rings in the completed several high pressure seal, found his appearance minor extrusion gap phenomenon. This shows tha

33、t the O-ring is achievable 138MPa about EHV sealed But media pressure is required to consider increased use of O-rings with the triangular pad combin</p><p>  附錄B 外文文獻(xiàn)中文翻譯</p><p>  超高液壓下O形環(huán)角密封的實(shí)

34、驗(yàn)研究</p><p><b>  摘 要:</b></p><p>  采用丁腈橡膠O形環(huán)實(shí)現(xiàn)超高壓容器端部角密封,對(duì)容器施加超高液壓做系列密封實(shí)驗(yàn)。結(jié)果表明,采用角密封結(jié)構(gòu),并對(duì)O形環(huán)壓縮率、截面直徑、密封間隙、橡膠硬度、密封面的粗糙度和密封件的形</p><p>  位公差等相關(guān)因素進(jìn)行合理匹配,嚴(yán)格控制,使用普通O形環(huán)可以實(shí)現(xiàn)138MP

35、a超高液壓的靜密封。</p><p>  關(guān)鍵詞: 超高壓 O形環(huán) 靜密封</p><p>  隨著現(xiàn)代工業(yè)的快速發(fā)展,超高壓越來(lái)越廣泛地運(yùn)用到超高壓殺茵、超高速冷凍、食品膨化工業(yè)、超臨界流體萃取、低鹽化處理、室溫高壓膨化以及加壓發(fā)酵等典型應(yīng)用場(chǎng)合。這類設(shè)備所生產(chǎn)的產(chǎn)品具有眾多優(yōu)越性,日益引起人們的普遍關(guān)注。如超高壓食品的生產(chǎn)具有瞬間加壓、作用均勻、操作安全和耗能低能很好地保持食物天然的色

36、、香、味和營(yíng)養(yǎng)成分的特點(diǎn),符合21世紀(jì)新型食品簡(jiǎn)便、安全、天然、營(yíng)養(yǎng)、衛(wèi)生、環(huán)保的消費(fèi)需求。因而有著顯著的社會(huì)效益和經(jīng)濟(jì)效益,具有巨大的潛在市場(chǎng)和廣闊的發(fā)展前景。</p><p>  但是,現(xiàn)今我國(guó)的超高壓食品的生產(chǎn)存在亟待提高工業(yè)裝備水平的問題,能否制造出經(jīng)濟(jì)、節(jié)能、安全、高效的處理設(shè)備成為制約超高壓食品處理技術(shù)市場(chǎng)推廣的主要瓶頸。其中,如何經(jīng)濟(jì)地制造超高壓容器并保證容器的超高壓密封尤為難點(diǎn)之所在。超高壓設(shè)備能

37、否正常運(yùn)行在很大程度上取決于密封結(jié)構(gòu)的完善性。高壓密封裝置的重量約占容器總重的10%~30%,而成本卻占總成本的15%~40%,因此密封設(shè)計(jì)工作是高壓容器設(shè)計(jì)的重要組成部分。由于許多超高壓設(shè)備為間隙操作,操作時(shí)不但要求物料能快裝快卸,且要求在開啟頻繁的情況下仍能實(shí)現(xiàn)多次可靠密封,一般使用快開式自緊密封結(jié)構(gòu)才能解決這一難題。普通O形橡膠密封環(huán)具有結(jié)構(gòu)簡(jiǎn)單、制造方便、價(jià)格便宜、安裝緊湊、使用方便和具有自緊密封作用等優(yōu)點(diǎn),被各行業(yè)廣泛使用。因

38、此實(shí)驗(yàn)采用丁腈橡膠(NBR)O形環(huán)(規(guī)格為32.5×3.55G,執(zhí)行標(biāo)準(zhǔn)為GB3452.1—92)進(jìn)行角密封實(shí)驗(yàn)研究。</p><p>  O形環(huán)的自緊密封原理</p><p><b>  1)預(yù)緊狀態(tài)</b></p><p>  O形環(huán)裝入密封部位后,其截面一般受到一定量的壓縮,由于O形環(huán)有良好的彈性,對(duì)接觸面會(huì)產(chǎn)生一定的接觸壓力,

39、從而實(shí)現(xiàn)預(yù)緊狀態(tài)下的密封。</p><p><b>  2)工作狀態(tài)</b></p><p>  當(dāng)密封腔充入液壓介質(zhì)后,在介質(zhì)壓力的作用下,O形環(huán)移向低壓一側(cè),封閉住密封間隙。隨著介質(zhì)壓力的增加,接觸壓力亦隨之增加,其峰值總是大于流體介質(zhì)壓力。這就保證了O形密封環(huán)的密封功能,也反映了O形密封環(huán)的自動(dòng)密封能力。經(jīng)驗(yàn)表明,對(duì)于普通橡膠材料,一般以13×105P

40、a為標(biāo)準(zhǔn)比壓。</p><p>  2主要密封參數(shù)的確定</p><p>  O形環(huán)的密封效果與壓縮率、截面直徑、密封間隙、橡膠硬度、密封面的粗糙度和密封件的形位公差等因素密切相關(guān)。在影響O形環(huán)密封性能的諸因素中,只要有1個(gè)參數(shù)的設(shè)計(jì)不合理就會(huì)降低其密封效果,甚至導(dǎo)致密封失效。因此下面就討論一下各影響因素具體數(shù)值的確定。</p><p><b>  1)壓

41、縮率</b></p><p>  形環(huán)密封是典型的壓縮型密封。O形環(huán)截面直徑的壓縮率是影響密封效果和使用壽命的重要參數(shù)。大多數(shù)情況下的泄漏與壓縮量不足有關(guān),但是過(guò)量壓縮又會(huì)造成裝拆困難和產(chǎn)生過(guò)大的殘余變形,而這將嚴(yán)重縮短其使用壽命。因此應(yīng)合理確定O形環(huán)的壓縮率。壓縮率W用下式表示:W=d0/hd0100%式中d0為O形環(huán)的截面直徑(mm),h為O形環(huán)壓縮后的截面尺寸。對(duì)于靜密封壓縮率W一般取10%~2

42、2%,本實(shí)驗(yàn)取為15%。</p><p><b>  2)截面直徑</b></p><p>  對(duì)于相同的壓縮量,截面直徑大的O形環(huán)的接觸寬度大,相應(yīng)的最大接觸應(yīng)力小,因此在橡膠O形環(huán)滿足結(jié)構(gòu)工藝等其他要求的情況下,盡可能選擇大截面的橡膠O形環(huán)。本實(shí)驗(yàn)容器密封面內(nèi)孔直徑為39mm,O形環(huán)截面直徑取3.55mm。</p><p><b>

43、;  3)密封間隙</b></p><p>  O形環(huán)在高壓力下很容易變形,容易被擠入密封間隙中去,造成損壞,因此必須對(duì)O形環(huán)的密封間隙加以嚴(yán)格控制。為了防止O形環(huán)發(fā)生擠出現(xiàn)象,并考慮到裝拆的難易程度,本實(shí)驗(yàn)的密封間隙取為0.1mm。</p><p><b>  4)硬度</b></p><p>  彈性模量小的O形環(huán),則最大接觸壓

44、應(yīng)力小,擠出量大,易破壞。所以當(dāng)內(nèi)壓很高時(shí),應(yīng)選用硬度較高的O形環(huán)。本實(shí)驗(yàn)采用的O形環(huán)硬度為1RHD(國(guó)際橡膠硬度等級(jí)80±5.5)密封面的粗糙度密封面的粗糙度是密封技術(shù)中的一個(gè)重要衡量指標(biāo)。如果密封面處有制造缺陷或縱向劃痕,則密封介質(zhì)很容易泄漏。《超高壓容器安全技術(shù)監(jiān)察規(guī)程》中規(guī)定超高壓容器密封面的粗糙度Ra應(yīng)當(dāng)小于或等于0.8μm。本實(shí)驗(yàn)密封面的粗糙Ra取0.4μm。</p><p>  5)密封件

45、的形位公差密</p><p>  封圓柱面的圓度、圓柱度公差按8級(jí)精度選取,端面對(duì)內(nèi)孔軸線的垂直度公差按7級(jí)精度選取。</p><p>  3實(shí)驗(yàn)裝置與密封結(jié)構(gòu)</p><p><b>  (1)實(shí)驗(yàn)裝置</b></p><p>  實(shí)驗(yàn)裝置由壓力源(YZGB型液袋式液壓脹管機(jī))、高壓連接管路、設(shè)計(jì)壓力為200MPa的超

46、高壓實(shí)驗(yàn)容器和軸向力平衡裝置(250KN的壓力機(jī))組成。</p><p><b>  (2) 密封原理</b></p><p>  當(dāng)旋緊螺栓時(shí),將帶動(dòng)托板向上移動(dòng)壓緊O形環(huán),O形環(huán)將貼緊芯軸的錐面和容器器壁,與錐面和軸之間分別形成環(huán)密封帶,形成預(yù)緊密封。在操作狀態(tài),隨著介質(zhì)(本實(shí)驗(yàn)加壓介質(zhì)為水)壓力的增加,O形環(huán)的壓縮量也隨之增大,接觸壓力亦相應(yīng)增加,從而實(shí)現(xiàn)可靠密

47、封。</p><p><b>  4實(shí)驗(yàn)過(guò)程</b></p><p>  (1)將O形環(huán)表面均勻涂覆少量潤(rùn)滑脂。將端蓋和芯軸用雙頭螺柱連接,把O形環(huán)安裝到芯軸上,用螺栓將托板連接到芯軸上以壓緊O形環(huán);</p><p>  (2)裝配高壓管、接頭螺母和小螺母,將接頭螺母與液壓介質(zhì)入口的螺紋連接;</p><p>  (3)

48、將下墊板、容器、端蓋與上墊板按圖1位置放置。接通壓力機(jī)電源,使兩平板壓緊上下兩墊板;</p><p>  (4)接通電源,預(yù)熱5min,旋轉(zhuǎn)溢流閥加壓。以10MPa的級(jí)差加壓,每級(jí)保壓5min,觀察有無(wú)泄漏;</p><p>  (5)記錄脹管機(jī)上的壓力顯示儀的液壓數(shù)值和液體泄漏情況。</p><p>  經(jīng)多次實(shí)驗(yàn)表明,只要合理選擇并嚴(yán)格控制影響密封性能的各主要因

49、素的數(shù)值,單獨(dú)使用普通O形環(huán)錐面密封結(jié)構(gòu)可以實(shí)現(xiàn)138MPa的可靠密封。由于實(shí)驗(yàn)設(shè)備的限制,本實(shí)驗(yàn)只做到138MPa的液壓密封,O形環(huán)仍有一定的密封潛力可以挖掘。</p><p>  突破了傳統(tǒng)資料認(rèn)為的O形環(huán)靜密封最高壓力為70MPa和當(dāng)工作壓力高于32MPa需要加擋圈以防止間隙擠出的限定,值得進(jìn)一步進(jìn)行實(shí)驗(yàn)研究。O形環(huán)在完成多次超高壓密封后,發(fā)現(xiàn)其外觀有輕微間隙擠出現(xiàn)象。這表明O形環(huán)雖可實(shí)現(xiàn)138MPa左右的

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