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1、<p><b>  外文資料譯文</b></p><p><b>  液壓系統(tǒng)</b></p><p><b>  緒論</b></p><p>  液壓站又稱液壓泵站,是獨(dú)立的液壓裝置。</p><p>  它按逐級要求供油。并控制液壓油流的方向、壓力和流量,適用于

2、主機(jī)與液壓裝置可分離的各種液壓機(jī)械上。</p><p>  用戶購后只要將液壓站與主機(jī)上的執(zhí)行機(jī)構(gòu)(油缸或油馬達(dá))用油管相連,液壓機(jī)械即可實(shí)現(xiàn)各種規(guī)定的動作和工作循環(huán)。</p><p>  液壓站是由泵裝置、集成塊或閥組合、油箱、電氣盒組合而成。各部件功能為:</p><p>  泵裝置--上裝有電機(jī)和油泵,是液壓站的動力源,將機(jī)械能轉(zhuǎn)化為液壓油的壓力能。</

3、p><p>  集成塊--由液壓閥及通道體組裝而成。對液壓油實(shí)行方向、壓力和流量調(diào)節(jié)。</p><p>  閥組合--板式閥裝在立板上,板后管連接,與集成塊功能相同。</p><p>  油箱--板焊的半封閉容器,上還裝有濾油網(wǎng)、空氣濾清器等,用來儲油、油的冷卻及過濾。</p><p>  電氣盒--分兩種型式。一種設(shè)置外接引線的端子板;一種配置

4、了全套控制電器。</p><p>  液壓站的工作原理:電機(jī)帶動油泵轉(zhuǎn)動,泵從油箱中吸油供油,將機(jī)械能轉(zhuǎn)化為液壓站的壓力能,液壓油通過集成塊(或閥組合)實(shí)現(xiàn)了方向、壓力、流量調(diào)節(jié)后經(jīng)外接管路并至液壓機(jī)械的油缸或油馬達(dá)中,從而控制液動機(jī)方向的變換、力量的大小及速度的快慢,推動各種液壓機(jī)械做功。</p><p><b>  1.1發(fā)展歷程 </b></p>

5、<p>  我國液壓(含液力,下同)、氣動和密封件工業(yè)發(fā)展歷程,大致可分為三個階段,即:20世紀(jì)50年代初到60年代初為起步階段;60~70年代為專業(yè)化生產(chǎn)體系成長階段;80~90年代為快速發(fā)展階段。其中,液壓工業(yè)于50年代初從機(jī)床行業(yè)生產(chǎn)仿蘇的磨床、拉床、仿形車床等液壓傳動起步,液壓元件由機(jī)床廠的液壓車間生產(chǎn),自產(chǎn)自用。進(jìn)入60年代后,液壓技術(shù)的應(yīng)用從機(jī)床逐漸推廣到農(nóng)業(yè)機(jī)械和工程機(jī)械等領(lǐng)域,原來附屬于主機(jī)廠的液壓車間有的獨(dú)立

6、出來,成為液壓件專業(yè)生產(chǎn)廠。到了60年代末、70年代初,隨著生產(chǎn)機(jī)械化的發(fā)展,特別是在為第二汽車制造廠等提供高效、自動化設(shè)備的帶動下,液壓元件制造業(yè)出現(xiàn)了迅速發(fā)展的局面,一批中小企業(yè)也成為液壓件專業(yè)制造廠。1968年中國液壓元件年產(chǎn)量已接近20萬件;1973年在機(jī)床、農(nóng)機(jī)、工程機(jī)械等行業(yè),生產(chǎn)液壓件的專業(yè)廠已發(fā)展到100余家,年產(chǎn)量超過100萬件,一個獨(dú)立的液壓件制造業(yè)已初步形成。這時,液壓件產(chǎn)品已從仿蘇產(chǎn)品發(fā)展為引進(jìn)技術(shù)與自行設(shè)計(jì)相結(jié)

7、合的產(chǎn)品,壓力向中、高壓發(fā)展,并開發(fā)了電液伺服閥及系統(tǒng),液壓應(yīng)用領(lǐng)域進(jìn)一步擴(kuò)大。氣動工業(yè)的起步比液壓稍晚幾年,到1967年開始建立氣動元件專業(yè)</p><p><b>  1.2目前狀況 </b></p><p><b>  1.21基本概況 </b></p><p>  經(jīng)過40多年的努力,我國液壓、氣動和密封件行業(yè)已形

8、成了一個門類比較齊全,有一定生產(chǎn)能力和技術(shù)水平的工業(yè)體系。據(jù)1995年全國第三次工業(yè)普查統(tǒng)計(jì),我國液壓、氣動和密封件工業(yè)鄉(xiāng)及鄉(xiāng)以上年銷售收入在100萬元以上的國營、村辦、私營、合作經(jīng)營、個體、“三資”等企業(yè)共有1300余家,其中液壓約700家,氣動和密封件各約300余家。按1996年國際同行業(yè)統(tǒng)計(jì),我國液壓行業(yè)總產(chǎn)值23.48億元,占世界第6位;氣動行業(yè)總產(chǎn)值4.19億元,占世界第10位。在軟件設(shè)計(jì)采用模塊化設(shè)計(jì),不同的液壓保護(hù)裝置用在

9、不同的礦中,這使高性能控制器的軟件存在很大的差異。</p><p>  1.22當(dāng)前供需狀況</p><p>  通過技術(shù)引進(jìn),自主開發(fā)和技術(shù)改造,高壓柱塞泵、齒輪泵、葉片泵、通用液壓閥門、油缸、無油潤滑氣動件和各類密封件第一大批產(chǎn)品的技術(shù)水平有了明顯的提高,并可穩(wěn)定的批量生產(chǎn),為各類主機(jī)提高產(chǎn)品水平提供了保證。另外,在液壓氣動元件和系統(tǒng)的CAD、污染控制、比例伺服技術(shù)等方面也取得一定成果

10、,并已用于生產(chǎn)。目前,液壓、氣動和密封件產(chǎn)品總計(jì)約有3000個品種、23000多個規(guī)格。其中,液壓有1200個品種、10000多個規(guī)格(含液力產(chǎn)品60個品種、500個規(guī)格);氣動有1350個品種、8000多個規(guī)格;橡塑密封有350個品種、5000多個規(guī)格,已基本能適應(yīng)各類主機(jī)產(chǎn)品的一般需要,為重大成套裝備的品種配套率也可達(dá)60%以上,并開始有少量出口。   1998年國產(chǎn)液壓件產(chǎn)量480萬件,銷售額約28億元(其中機(jī)械系統(tǒng)約占70%)

11、;氣動件產(chǎn)量360萬件,銷售額約5.5億元(其中機(jī)械系統(tǒng)約占60%);密封件產(chǎn)量約8億件,銷售額約10億元(其中機(jī)械系統(tǒng)約占50%)。據(jù)中國液壓氣動密封件工業(yè)協(xié)會1998年年報(bào)統(tǒng)計(jì),液壓產(chǎn)品產(chǎn)銷率為97 .5%(液力為101%),氣動為95.9%,密封為98.7%。這充分反映了產(chǎn)銷</p><p>  現(xiàn)場總線的使用上,在德國的EEP公司采用現(xiàn)場總線技術(shù)實(shí)現(xiàn)信息的傳遞,而MARCO公司使用自定義格式收集器技術(shù)。開

12、放集電極技術(shù)。目前,在國內(nèi)運(yùn)用成熟和廣泛的的CAN總線技術(shù)是德國BOTCH公司提出的。在實(shí)際系統(tǒng)中控制器之間的通信是由雙RS422傳遞大量數(shù)據(jù)實(shí)現(xiàn)的?,F(xiàn)場總線地下工作時需要特殊處理。由于本質(zhì)安全要求的考慮,電源的電量應(yīng)受到嚴(yán)格控制。通常每個電源只能提供五或六個控制器,電磁先導(dǎo)閥的電量。因此,這個系統(tǒng)需要大量的獨(dú)立電源。為了為了避免電流不平衡導(dǎo)致破壞原有的安全性,控制器之間的數(shù)據(jù)信號需通過信號隔離器,可以實(shí)現(xiàn)電氣信息的通斷連接。</

13、p><p><b>  1.3今后發(fā)展走勢</b></p><p>  1.31影響發(fā)展的主要因素</p><p>  企業(yè)產(chǎn)品開發(fā)能力不強(qiáng),技術(shù)開發(fā)的水平和速度不能完全滿足先進(jìn)主機(jī)產(chǎn)品、重大技術(shù)裝備和進(jìn)口設(shè)備的配套和維修需要;   (2)不少企業(yè)的制造工藝、裝備水平和管理水平都較落后,加上質(zhì)量意識不強(qiáng),導(dǎo)致產(chǎn)品性能水平低、質(zhì)量不穩(wěn)定、可靠性差,

14、服務(wù)不及時,缺乏使用戶滿意和信賴的名牌產(chǎn)品;   (3)行業(yè)內(nèi)生產(chǎn)專業(yè)化程度低,力量分散,低水平重復(fù)嚴(yán)重,地區(qū)和企業(yè)之間產(chǎn)品趨同,盲目競爭,相互壓價(jià),使企業(yè)效益下降,資金缺乏、周轉(zhuǎn)困難,產(chǎn)品開發(fā)和技術(shù)改造投入不足,嚴(yán)重地制約了行業(yè)整體水平的提高以及競爭實(shí)力的增強(qiáng);   (4)國內(nèi)市場國際化程度日益提高,國外公司紛紛進(jìn)入中國市場參與競爭,加上國內(nèi)私營、合作經(jīng)營、個體、三資等企業(yè)的崛起,給國有企業(yè)造成愈來愈大的沖擊。</p>

15、<p><b>  1.32發(fā)展走勢</b></p><p>  隨著社會主義市場經(jīng)濟(jì)的不斷深化,液壓、氣動和密封產(chǎn)品的市場供求關(guān)系發(fā)生較大變化,長期來以“短缺”為特征的賣方市場已基本成為以“結(jié)構(gòu)性過?!睘樘卣鞯馁I方市場所取代。從總體能力看,已處于供大于求的態(tài)勢,特別是一般低檔次液壓、氣動和密封件,普遍供過于求;而主機(jī)急需的技術(shù)含量高的高參數(shù)、高附加值的高檔產(chǎn)品,又不能滿足市場

16、需要,只能依賴于進(jìn)口。在我國加入WTO后,其沖擊有可能更大。因此,“十五”期間行業(yè)產(chǎn)值的增長,決不能依賴于量的增長,而應(yīng)針對行業(yè)自身的結(jié)構(gòu)性矛盾,加大力度,調(diào)整產(chǎn)業(yè)結(jié)構(gòu)和產(chǎn)品結(jié)構(gòu),也就是應(yīng)依靠質(zhì)的提高,促進(jìn)產(chǎn)品技術(shù)升級,以適應(yīng)和拉動市場需求,求得更大的發(fā)展。</p><p>  Hydraulic system</p><p>  Introduction</p><p

17、>  Hydraulic Pump Station also known as the stations are independent hydraulic device. </p><p>  It requested by the oil gradually. And controlling the hydraulic oil flow direction, pressure and flow rate

18、, applied to the mainframe and hydraulic devices separability of hydraulic machinery. </p><p>  Users will be provided after the purchase hydraulic station and host of implementing agencies (motor oil or fue

19、l tanks) connected with tubing, Hydraulic machinery can be realized from these movements and the work cycle.</p><p>  Hydraulic pump station is installed, Manifold or valve combination, tanks, a combination

20、of electrical boxes.</p><p>  Functional components : </p><p>  Pump device -- is equipped with motors and pumps, hydraulic station is the source of power. to mechanical energy into hydraulic oi

21、l pressure can be. </p><p>  Manifold -- from hydraulic valve body and channel assembled. Right direction for implementation of hydraulic oil, pressure and flow control. </p><p>  Valve portfoli

22、o -- plate valve is installed in up board after board connects with the same functional IC. </p><p>  Tank -- plate welding semi-closed containers, also loaded with oil filtering network, air filters, used o

23、il, oil filters and cooling. </p><p>  Electrical boxes -- at the two patterns. A set of external fuse terminal plate; distribution of a full range of electrical control. </p><p>  Hydraulic Sta

24、tion principle : motor driven pump rotation, which pump oil absorption from the oil tank. to mechanical energy into hydraulic pressure to the station, hydraulic oil through Manifold (or valve combinations) realized the d

25、irection, pressure, After adjusting flow pipe and external to the cylinder hydraulic machinery or motor oil, so as to control the direction of the motive fluid transformation force the size and speed the pace of promotin

26、g the various acting hydraulic machinery.</p><p>  A development course </p><p>  China Hydraulic (including hydraulic, the same below), pneumatic and seals industrial development process can be

27、 broadly divided into three phases, namely : 20 early 1950s to the early 1960s, the initial stage; 60's and 70 for specialized production system ;80~90's growth stage for the rapid development stage. Which, hydra

28、ulic industry in the early 1950s from the machine tool industry production of fake Soviet Union grinder, broaching machine, copying lathe, and other hydraulic drive started, Hy</p><p>  Since the 1980s, in t

29、he country's reform and opening up policy guidelines, with the development of the machinery industry, based mainframe pieces behind the conflicts have become increasingly prominent and attracted the attention of the

30、relevant departments. To this end, the Ministry of the original one in 1982, formed the basis of common pieces of Industry, will be scattered in the original machine tools, agricultural machinery, mechanical engineering

31、industries centralized hydraulic, pneumatic</p><p>  the current situation </p><p>  1.2.1Basic Profiles </p><p>  After 40 years of efforts, China hydraulic, pneumatic and sealing

32、industry has formed a relatively complete categories. a certain level of technical capacity and the industrial system. According to the 1995 Third National Industrial Census statistics, hydraulic, Pneumatic seals and ind

33、ustrial 370,000 annual sales income of 100 million yuan in state-owned, village-run, private and cooperative enterprises, individual, "three capital" enterprises with a total of more than 1,300, of which about

34、700 </p><p>  1.22 the current supply and demand profiles </p><p>  Through the introduction of technology, independent development and technological innovation, and high-pressure piston pump, g

35、ear pumps, vane pump, General Motors hydraulic valves, tanks, Non-lubricated aerodynamic pieces and various seals of the first large technology products has increased noticeably. stability of the mass production may, for

36、 various mainframe products provide a level of assurance. In addition, hydraulic and pneumatic components of the CAD system, pollution control, proportion</p><p>  1998 pieces of homemade hydraulic output 4.

37、8 million. sales of about 28 billion (of which about 70% mechanical systems); aerodynamic pieces yield 3.6 million. sales of about 5.5 billion (of which about 60% of mechanical systems); Seals output of about 800 million

38、. sales of about 10 billion (of which about 50% mechanical systems). According to the China Hydraulic Pneumatic Seals Industry Association 1998 annual report, hydraulic product sales rate of 97. 5% (101% for hydraulic),

39、pneumatic 95.9%, </p><p>  My hydraulic, pneumatic and sealing industry has attained a great deal of progress, but with mainframe development needs, and the world's advanced level, there are still many g

40、aps, mainly reflected in the product variety, performance and reliability, and so on. Hydraulic products as an example, products abroad only one-third, life for half abroad. In order to meet key mainframe, and mainframe

41、imports of major technology and equipment needs, every year a large number of hydraulic, pneumatic and s</p><p>  the development trend of the future </p><p>  1.31 affect the development of the

42、 main factors </p><p>  (1) product development ability, and the level of technological development and speed can not completely meet the advanced mainframe products, major equipment and technology imported

43、equipment and maintenance support; </p><p>  (2) the number of enterprises manufacturing technology, the level of equipment and management standards are comparatively backward, coupled with a strong sense of

44、 quality, resulting in low levels of product performance, quality, Reliability poor services in a timely manner, lack of user satisfaction and trust of the brand-name products;</p><p>  (3) industry speciali

45、zation of production low, scattered strength, low repeat serious, between regions and enterprises of convergence products, blindly compete with each other, driving down prices, the decline of enterprise returns, lack of

46、funds, liquidity difficulties, product development and technological transformation is inadequate and seriously restricted the industry to improve the overall level of competition and the increase of strength; </p>

47、<p>  (4) The internationalization of the domestic market and the increasing degree of foreign companies have entered the Chinese market and participate in competition with the domestic private and cooperative ent

48、erprises, individuals, foreign-funded enterprises, such as the rise of state-owned enterprises due to the growing impact. </p><p>  1.32 the development trend </p><p>  As the socialist market e

49、conomy continues to deepen, hydraulic, pneumatic and sealing products in the market supply and demand and there is a greater change, long ago to a "shortage" of the seller's market has basically become a &q

50、uot;structural surplus" of the characteristics of the buyer's market place . Overall capacity, is already in oversupply situation, in particular the general low level of hydraulic, pneumatic and seals, the gener

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