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1、<p>  本科生畢業(yè)設(shè)計(jì)外文翻譯</p><p><b>  學(xué)生姓名:xxx</b></p><p>  學(xué) 號(hào):xxx</p><p>  專(zhuān) 業(yè):機(jī)械設(shè)計(jì)制造及其自動(dòng)化</p><p>  班 級(jí):機(jī)05-3班</p><p><b>  指導(dǎo)教師:x

2、xx</b></p><p>  In hydraulic support battery solution control system use question and countermeasure</p><p>  Zhang Mingli(張命林)</p><p>  (Zhengzhou coal mine mechanical group

3、Limited liability company Henan Zhengzhou 450013)</p><p>  Luo Yueyong(羅躍勇)</p><p>  (Beijing world Ma Ke battery solution control system Limited company Beijing 100013)</p><p>  Ab

4、stract: To further display the support battery solution control system's performance, demonstrates the support battery solution control system's superiority fully, In many year research's foundations, elabora

5、ted systematically the support battery solution control system several aspects which displays in the domestic and foreign application condition and the present influence and the restriction domestic product support batte

6、ry solution control system use and the performance. Proposed the formu</p><p>  Key word: Hydraulic support; Battery solution control system; Filtration system; Filter fineness</p><p>  1、hydrau

7、lic support battery solution control system's superiority</p><p>  The hydraulic support battery solution control system is by electronic installations and the hydraulic circuit control portion and so on

8、 monolithic integrated circuit, sensor is composed, may need to control the hydraulic support automatic performance according to the production the system.</p><p> ?、貰ehind may fall the hydraulic support, to

9、 try to break up a fight, to rise the frame, the passage front part conveyer, to pull the conveyer, to receive protects helps the board, to extend protects helps the board, the atomization water spray and puts goes again

10、st movements and so on coal to change by the original man-power manual operation the battery solution automatic control, the sequencing to operate, Can match with the highly effective coal mining machine speeds up the wo

11、rking surface adva</p><p> ?、贛ay realize with machine the automated work, reduces the operators who the labor intensity, the improvement work condition, reduces the working surface.</p><p> ?、跰a

12、y solve under the special geological condition and the difficult working condition technique of production question, for example, in the thin coal bed working surface personnel are unable under the condition which operat

13、es in the working surface, may realize the non-hominization working surface (to with coal plow system coordination use).</p><p> ?、躆ay realize the multi-frames simultaneously to push the conveyer and may the

14、 quota advancement, guaranteed that conveyer gentle curving, middle avoids the trough attachment point having the oversized stress, lengthens conveyer's life, simultaneously may protect working surface conveyer's

15、 straight, realizes the working surface straight passage.</p><p> ?、軪asy to realize the belt pressure to move to the frame, and prevents the roof failure accident regarding the protection roof's stabilit

16、y to be advantageous.</p><p> ?、轒ay control the support initially to support the strength well, obviously improves the supports and protections effect and the working surface management level.</p><

17、;p>  2、 domestic and foreign application situation</p><p>  Overseas started in the 1970s to develop the development hydraulic support with the electrically controlled system, in the 80s entered the subst

18、antive application stage. To the 90s, the hydraulic support battery solution automatic control technology had been already mature, the operating performance and the reliability have been able to satisfy the operation req

19、uirements, thus develops very rapidly, becomes produces the coal country synthesis to pick the working surface hydraulic support's stand</p><p>  3、 at present faces question, reason and key to the situa

20、tion</p><p>  Along with battery solution control system's promoted application, also has met some questions, is restricting the battery solution control system's use and the performance full display

21、, concrete manifestation in the following several aspects:</p><p> ?、賂he system hydraulic element failure rate compares the complete set introduction system to compare high somewhat, specially in working sur

22、face trial production and production initial period. In recent years, along with the home production processing level's enhancement, hydraulic elements and so on support as well as battery solution cross valve has re

23、alized the manufacture domestically, carries on the systems assembly together through several factories, this had a new problem, each factory act</p><p>  ②Because the battery solution control cross valve st

24、ructure and the performance need the medium cleanliness to be high, the system necessary 25m precision filter, set the new request to the medium and the emulsion allocated proportion. Along with these years battery solut

25、ion control system in the domestic promoted application, appeared generally, because the emulsion choice unqualified, the density allocated proportion causes in the medium to stick the thick shape material separation unr

26、easonabl</p><p> ?、跢ilters the system standard not to be unified, the part manufacture domestically filter element manufacture quality is unqualified, takes substandard products as fine products, causes the

27、battery solution control system not to be unstable, failure rate higher.</p><p>  At present domestic is not unified to filter fineness's definition various professions standard, even some filter element

28、 Manufacturer and the user do not know the filter fineness the definition method, but internationally has several different definition methods about the filter fineness, Has three kinds approximately: 1) the hydraulic pr

29、essure filtration technology use stipulation's experiment powder (ISOMTD), the experimental standard is ISO16889 "Adopts Cut-and-try method Many times". Every </p><p> ?、贔ilter and so on automo

30、bile, machine shop truck, common equipment lubrication, fuel oil mostly use the SAE806b standard. It uses the biggest pellet passage, the use glass micro bead or the AC experiment powder, joins the powder after the test

31、platform from the filter downstream sample, the fluid type (0.8 or 0.5μm) filters and collects the pellet with the millipore filter, then examined under the microscope. If discovers the biggest pellet for 20μm, then filt

32、er fineness for 20μm.</p><p>  ③The air cleaner, the purification environment use the filter, usually by weight filter efficiency nominal filtration characteristic. The custom said that several “9” the field

33、 test powder is ACFTD. Although above 3 kind of filter's filter fineness defines differently, but based on one test method, namely pellet transmission law, Therefore the modern filtration counting abolished the forme

34、r aperture measuring method to the filter characteristic evaluation and filters the material item of number </p><p> ?、蹺ntire filtration system not perfect or inadequate system, creates the system existence

35、crack or the system function cannot display fully, serious influence battery solution control system performance display. Because does not have the filtration or the filter position is inappropriate, creates key protects

36、 the part not to obtain the protection, even if on the other hand had the filtration system, must complete the prevention, avoids the pollutant entering the system as far as possible, achieve</p><p>  4、conc

37、lusion</p><p>  The hydraulic support battery solution control system realizes the coal mine safety highly effective mining key technologies, realizes the high production highly effective working surface ess

38、ential condition. But must use the good battery solution control system, the display battery solution control system's superiority truly, only through improves the battery solution control system itself quality to be

39、 not enough. Must from the support and the hydraulic services production, the medium cleanlin</p><p><b>  Reference</b></p><p> ?。郏保荨埩肌∫簤褐Ъ茈娨嚎刂葡到y(tǒng)的應(yīng)用現(xiàn)狀及發(fā)展趨勢(shì)[J].煤炭科學(xué)技術(shù).2003(2).</p&

40、gt;<p> ?。郏玻荨〈魈煲怼】讖匠叽绮皇沁^(guò)濾精度[J].液壓氣動(dòng)與密封.2003(6).</p><p>  液壓支架電液控制系統(tǒng)使用中的問(wèn)題及對(duì)策</p><p><b>  張命林</b></p><p> ?。ㄠ嵵菝旱V機(jī)械集團(tuán)有限責(zé)任公司 河南鄭州 450013)</p><p><b&g

41、t;  羅躍勇</b></p><p>  (北京天地瑪珂電液控制系統(tǒng)有限公司 北京 100013)</p><p>  摘要:為了進(jìn)一步發(fā)揮支架電液控制系統(tǒng)的性能,充分展示支架電液控制系統(tǒng)的優(yōu)勢(shì),在多年研究的基礎(chǔ)上,系統(tǒng)地闡述了支架電液控制系統(tǒng)在國(guó)內(nèi)外的應(yīng)用狀況及目前影響和制約國(guó)產(chǎn)支架電液控制系統(tǒng)使用和性能發(fā)揮的幾個(gè)方面。提出了制定電液控制系統(tǒng)相關(guān)元部件生產(chǎn)制造統(tǒng)一標(biāo)準(zhǔn)、統(tǒng)一

42、過(guò)濾元件行業(yè)標(biāo)準(zhǔn)及建立電液控制系統(tǒng)工作面主動(dòng)預(yù)防與被動(dòng)過(guò)濾防護(hù)相結(jié)合的清潔度控制體系的重要性,建立健全過(guò)濾防護(hù)體系,進(jìn)一步發(fā)揮國(guó)產(chǎn)支架電液控制系統(tǒng)性能。</p><p>  關(guān)鍵詞:液壓支架;電液控制系統(tǒng);過(guò)濾體系;過(guò)濾精度</p><p>  1、液壓支架電液控制系統(tǒng)的優(yōu)勢(shì)</p><p>  液壓支架電液控制系統(tǒng)是由單片機(jī)、傳感器等電子裝置和液壓回路控制部件組成

43、的,可以根據(jù)生產(chǎn)需要控制液壓支架自動(dòng)動(dòng)作的系統(tǒng)。</p><p>  ①可以將液壓支架的降架、拉架、升架、推移前部輸送機(jī)、拉后部輸送機(jī)、收護(hù)幫板、伸護(hù)幫板、噴霧灑水及放頂煤等動(dòng)作由原來(lái)的人工手動(dòng)操作改為電液自動(dòng)控制、程序化操作,能夠與高效采煤機(jī)相匹配加快工作面推進(jìn)速度,顯著提高采煤工作面的生產(chǎn)效率。</p><p> ?、诳梢詫?shí)現(xiàn)跟機(jī)自動(dòng)化作業(yè)、降低勞動(dòng)強(qiáng)度、改善勞動(dòng)條件、減少工作面的操作

44、人員。</p><p> ?、劭梢越鉀Q特殊地質(zhì)條件和困難生產(chǎn)條件下的生產(chǎn)工藝問(wèn)題,例如在薄煤層工作面人員無(wú)法在工作面內(nèi)操作的條件下,可以實(shí)現(xiàn)無(wú)人化工作面(需與刨煤機(jī)系統(tǒng)配合使用)。</p><p>  ④可實(shí)現(xiàn)多架同時(shí)推輸送機(jī)并可定量推進(jìn),保證輸送機(jī)平緩彎曲,避免中部槽連接處產(chǎn)生過(guò)大的應(yīng)力,延長(zhǎng)輸送機(jī)的壽命,同時(shí)可以保護(hù)工作面輸送機(jī)的平直性,實(shí)現(xiàn)工作面的平直推移。</p>&

45、lt;p> ?、菀子趯?shí)現(xiàn)帶壓移架,對(duì)于保護(hù)頂板的穩(wěn)定性和防止冒頂事故非常有利。</p><p> ?、蘅梢暂^好地控制支架初撐力,顯著改善支護(hù)效果和工作面管理水平。</p><p>  2、國(guó)內(nèi)外的應(yīng)用情況</p><p>  國(guó)外在20世紀(jì)70年代開(kāi)始開(kāi)發(fā)研制液壓支架用電控系統(tǒng),80年代進(jìn)入實(shí)質(zhì)性應(yīng)用階段。到了90年代,液壓支架電液自動(dòng)控制技術(shù)已經(jīng)成熟,工作性

46、能和可靠性已能滿(mǎn)足使用要求,因而發(fā)展十分迅速,成為發(fā)達(dá)產(chǎn)煤國(guó)家綜采工作面液壓支架的標(biāo)準(zhǔn)控制裝備。據(jù)不完全統(tǒng)計(jì),目前已有300多個(gè)綜采工作面使用電液控制液壓支架,主要集中在美國(guó)、澳大利亞、德國(guó)、中國(guó)、斯洛文尼亞、南非、俄羅斯、波蘭、墨西哥、加拿大等國(guó)家。目前中國(guó)有131個(gè)綜采工作面使用電液控制系統(tǒng),PM31電液控制系統(tǒng)是目前國(guó)產(chǎn)液壓支架的主流電液控制系統(tǒng),占國(guó)產(chǎn)液壓支架電液控制系統(tǒng)市場(chǎng)80%以上的份額。</p><p&

47、gt;  3、目前面臨的問(wèn)題、原因及解決途徑</p><p>  隨著電液控制系統(tǒng)的推廣應(yīng)用,也遇到了一些問(wèn)題,制約著電液控制系統(tǒng)的使用和性能的充分發(fā)揮,具體表現(xiàn)在以下幾個(gè)方面:</p><p> ?、傧到y(tǒng)液壓元件故障率較全套引進(jìn)系統(tǒng)相比偏高一些,特別是在工作面試生產(chǎn)和生產(chǎn)初期。近幾年,隨著國(guó)內(nèi)生產(chǎn)加工水平的提高,支架以及電液換向閥等液壓元件實(shí)現(xiàn)了國(guó)產(chǎn)化,通過(guò)幾個(gè)廠家來(lái)共同進(jìn)行系統(tǒng)配套,這

48、就出現(xiàn)了一個(gè)新的問(wèn)題,各個(gè)廠家根據(jù)各自產(chǎn)品性能要求 確定制造標(biāo)準(zhǔn),而沒(méi)有考慮到整個(gè)電液控制系統(tǒng)的性能要求。以清潔度為例,國(guó)內(nèi)支架在生產(chǎn)知道電液控支架時(shí)還是沿用原有手動(dòng)控制系統(tǒng)支架生產(chǎn)清潔度控制標(biāo)準(zhǔn),這就造成支架使用問(wèn)題,但由于電液控制換向閥對(duì)清潔度要求高,整個(gè)支架電液控制系統(tǒng)使用初期電磁先導(dǎo)閥和主閥由于污染損壞嚴(yán)重,故障率增加。一般都需要一段時(shí)間(一兩個(gè)月)的使用后,系統(tǒng)才能恢復(fù)正常。這還是以有一個(gè)好的過(guò)濾系統(tǒng)為前提。如果過(guò)濾系統(tǒng)在這個(gè)

49、過(guò)程由于污染嚴(yán)重堵塞失效,將造成真?zhèn)€液壓系統(tǒng)惡性循環(huán),系統(tǒng)故障率進(jìn)一步增加,甚至造成系統(tǒng)癱瘓。目前,迫切需要根據(jù)電液控制系統(tǒng)要求,制定電液控制系統(tǒng)相關(guān)元部件加工制造標(biāo)準(zhǔn),從而確保整個(gè)電液控制系統(tǒng)的可靠穩(wěn)定運(yùn)行。</p><p> ?、谟捎陔娨嚎刂茡Q向閥結(jié)構(gòu)及性能需要介質(zhì)清潔度高,系統(tǒng)均配套25µm的精密過(guò)濾器,對(duì)介質(zhì)和乳化液配比提出了新的要求。隨著這幾年電液控制系統(tǒng)在國(guó)內(nèi)的推廣應(yīng)用,普遍出現(xiàn)了由于乳化液

50、選擇不合格、濃度配比不合理造成介質(zhì)中粘稠狀物質(zhì)析出,以致工作面過(guò)濾系統(tǒng)嚴(yán)重堵塞,支架動(dòng)作緩慢或不能動(dòng)作,濾芯大面積堵塞失效。</p><p> ?、圻^(guò)濾系統(tǒng)標(biāo)準(zhǔn)不統(tǒng)一,部分國(guó)產(chǎn)化濾芯制造質(zhì)量不合格,以次充好,造成電液控制系統(tǒng)不穩(wěn)定,故障率高等。</p><p>  目前國(guó)內(nèi)對(duì)過(guò)濾精度的定義各行業(yè)標(biāo)準(zhǔn)不統(tǒng)一,甚至一些濾芯生產(chǎn)廠家和用戶(hù)不知道過(guò)濾精度的定義方法,而國(guó)際上關(guān)于過(guò)濾精度有幾種不同的

51、定義方法,大致有三種:1)液壓過(guò)濾技術(shù)使用規(guī)定的實(shí)驗(yàn)粉末(ISOMTD),試驗(yàn)標(biāo)準(zhǔn)為ISO16889《多次通過(guò)實(shí)驗(yàn)法》。凡采用ISO16889和試驗(yàn)粉末為ISOMTD者,在標(biāo)準(zhǔn)過(guò)濾器的精度時(shí)用(C)注明。該試驗(yàn)法是將試驗(yàn)系統(tǒng)加入統(tǒng)一濃度ISOMTD粉末后,在過(guò)濾器上下游分別取樣測(cè)試,并選擇合適的至少5種顆粒尺寸范圍,用顆粒計(jì)數(shù)器測(cè)定并計(jì)數(shù)。上游某尺寸顆粒數(shù)比下游同尺寸顆粒數(shù),比值為β。β值取5,20,75,200,2000定為自己企業(yè)評(píng)

52、定過(guò)濾器水平(這一比值就是過(guò)濾效率)。假如5μm顆粒上下游比值為20,則可理解為5μm過(guò)濾效率為95%。通常標(biāo)注過(guò)濾器精度寫(xiě)成=20,x為所測(cè)定β=20的那一顆粒尺寸。 </p><p>  ②汽車(chē)、工程車(chē)、一般設(shè)備潤(rùn)滑、燃油等過(guò)濾器大多用SAE806b標(biāo)準(zhǔn)。它采用最大顆粒通過(guò)法,使用玻璃微珠或AC試驗(yàn)粉末,在試驗(yàn)臺(tái)上加入粉末后從過(guò)濾器下游取樣,液樣用微孔濾膜(0.8或0.5μm)過(guò)濾并收集顆粒,然后在顯微鏡下查

53、看。如果發(fā)現(xiàn)最大顆粒為20μm,則過(guò)濾精度為20μm。</p><p> ?、劭諝鉃V清器、凈化環(huán)境用濾器,通常以重量過(guò)濾效率標(biāo)稱(chēng)過(guò)濾特性。習(xí)慣稱(chēng)幾個(gè)“9”使用試驗(yàn)粉末為ACFTD。以上3種濾器的過(guò)濾精度雖然定義不同,但都基于一種測(cè)試方法,即顆粒傳輸法,所以現(xiàn)代過(guò)濾計(jì)數(shù)對(duì)過(guò)濾器特性的評(píng)定都廢除了以往的孔徑測(cè)定法和濾材目數(shù)法,但在煤炭行業(yè)很多企業(yè)和用戶(hù)依然沿用濾材數(shù)目法。這就造成市場(chǎng)上同樣25μm的過(guò)濾器實(shí)際精度相差

54、很大。另一方面,對(duì)于高精度過(guò)濾器(25μm),濾材的選擇和加工很?chē)?yán)格,一些企業(yè)偷工減料選擇劣質(zhì)濾材或加工工藝不過(guò)關(guān),造成濾芯加工缺陷。雖然濾材選擇合適但由于加工工藝不合格造成過(guò)濾器成品精度明顯降低,不能滿(mǎn)足系統(tǒng)要求。所以應(yīng)盡快制定電液控制系統(tǒng)用過(guò)濾器生產(chǎn)、加工及檢驗(yàn)行業(yè)標(biāo)準(zhǔn)尤為重要。</p><p> ?、苷麄€(gè)過(guò)濾系統(tǒng)不健全或不成體系,造成系統(tǒng)存在漏洞或系統(tǒng)功能不能充分發(fā)揮,嚴(yán)重影響電液控制系統(tǒng)性能發(fā)揮。由于沒(méi)有

55、過(guò)濾或過(guò)濾器位置不合適,造成重點(diǎn)保護(hù)元件沒(méi)有得到保護(hù),另一方面即使有了過(guò)濾體系,也必須做好預(yù)防,盡可能避免污染物進(jìn)入系統(tǒng),做到主動(dòng)預(yù)防和被動(dòng)過(guò)濾防護(hù)相結(jié)合的清潔度保證體系,只有這樣才能保證整個(gè)電液控制系統(tǒng)的可靠穩(wěn)定運(yùn)行。</p><p><b>  4、結(jié)論</b></p><p>  液壓支架電液控制系統(tǒng)是實(shí)現(xiàn)煤礦安全高效開(kāi)采的關(guān)鍵技術(shù),是實(shí)現(xiàn)高產(chǎn)高效工作面的必要條

56、件。但要真正使用好電液控制系統(tǒng)、發(fā)揮電液控制系統(tǒng)的優(yōu)越性,僅通過(guò)提高電液控制系統(tǒng)本身質(zhì)量還是遠(yuǎn)遠(yuǎn)不夠的。必須從支架及其液壓附件生產(chǎn)、介質(zhì)清潔度控制和現(xiàn)場(chǎng)維護(hù)等幾個(gè)方面共同著手,才能充分展示電液控制系統(tǒng)的優(yōu)勢(shì)。</p><p><b>  參考文獻(xiàn)</b></p><p>  [1] 張良 液壓支架電液控制系統(tǒng)的應(yīng)用現(xiàn)狀及發(fā)展趨勢(shì)[J].煤炭科學(xué)技術(shù).2003(2).&

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