2023年全國碩士研究生考試考研英語一試題真題(含答案詳解+作文范文)_第1頁
已閱讀1頁,還剩13頁未讀 繼續(xù)免費閱讀

下載本文檔

版權(quán)說明:本文檔由用戶提供并上傳,收益歸屬內(nèi)容提供方,若內(nèi)容存在侵權(quán),請進行舉報或認領(lǐng)

文檔簡介

1、<p><b>  外文資料翻譯</b></p><p>  Dump Truck</p><p>  Dump Truck mainly refers to the delivery of goods unloaded the car and there is dumping the car, also known as Dump Trucks. <

2、/p><p>  Dump Truck is characterized by its compartment can be tilted a certain angle, so that unloading the goods inside. Tilting train is a Dump Truck engine power, through the dumping of bodies to complete.

3、</p><p>  Dump Truck from the early 20th century there has been continuous development and perfection, has become the main vehicle of transport of goods. Dump Truck unloading a high degree of mobility and me

4、chanization a bit, usually with shovel loaders, excavators, or belt conveyors and other ancillary use to achieve loading and unloading mechanization, which can greatly shorten the handling time and improve transport effi

5、ciency and save labor, reduce labor strength. As the car manufacturing industry, Du</p><p>  First, the status of technology development at home and abroad </p><p>  1. Humanization </p>

6、<p>  Further improve vehicle safety, vehicle safety, including performance, braking performance is further enhanced convenience and driver control, comfort is the car at home and abroad reflect the requirements o

7、f human development, which is reflected in the body, chassis and other aspects . </p><p>  1. Suspension System </p><p>  Foreign high-end Dump Truck, such as SCANIA, VOLVO, etc., air suspension

8、 with automatic adjustment, and basic domestic or leaf spring, a better use of the rubber suspension. </p><p>  1. Transmission System </p><p>  Main Foreign is automatic transmission. China mai

9、nly with manual gearbox, there are some manufacturers began to try to configure the chassis automatic transmission. </p><p>  1. Braking Systems </p><p>  Electric control system mainly foreign

10、(ECBS) and air disc brakes and ABS electronic control system installed. China mainly uses drum brakes, ABS, electronic brake system installed in the smaller, but also began developing the disc brake manufacturers.</p&

11、gt;<p>  (4)Body Systems </p><p>  Dump Truck body of domestic comfort than the gap in Europe is still a great car. But high-end cab, driving and ride comfort has been greatly improved than before.<

12、;/p><p>  2. Specialization </p><p>  Exclusive of foreign Dump Truck classification is increasingly apparent. In addition to general engineering of Dump Truck, but also according to the needs and

13、purposes century, the development of a dedicated is Dump Truck. </p><p>  (1)Road salt cleaning truck </p><p>  Of snow, snow days will be transported to the road salt, snow on the road sweeping

14、, snow spraying of salt. </p><p>  (2) Class of fluid transport truck pollution </p><p>  Achieve pollution class fluid collection, transportation and dumping, can better protect the vehicle cha

15、ssis, suitable for road paving and construction of the gravel material transport. </p><p>  China Dump Truck of professional classification is not very clear that the Dump Truck currently mainly used in cons

16、truction, mining, coal transportation, and its degree of specialization than the foreign classification there a larger gap. </p><p>  3. Structure Optimization </p><p>  European high-strength s

17、teel materials often used Dump Truck or a U-shaped carriage frame structure, the advantages are: light weight, great load, more payload can be loaded indirectly increase the loading efficiency; reduce fuel consumption, l

18、ow center of gravity, good stability , lifting more goods at the time the play, easy to discharge; integral bearing, no or only a few ribs, a small amount of welding; more modern design, the outer surface of a large flat

19、, easy to paste advertisements, or o</p><p>  For cost and processing considerations, the domestic truck still ordinary steel, steel plate as the main material. </p><p>  4. Environmental protec

20、tion </p><p>  As the world's growing environmental protection, national environmental protection requirements on the vehicles are more stringent. Dump Truck load of goods sealing requirements increasing

21、. </p><p>  Automotive engine technology represents a country's industrial level. Developed countries in Europe to Euro V vehicle emissions standards, and requirements of the domestic truck is currently

22、the country Ⅲ standard, domestic and foreign well as very large gap, and reduce vehicle emissions of key technologies are only few the hands of countries, China still has great technical follow up and development process

23、. Further enhance the environmental protection requirements, sealing requirements of the </p><p>  Second, the main structure and function </p><p>  Dump Truck chassis and coat by the two major

24、components, two types of chassis they use a stereotypical car chassis. Dump Truck as a shorter wheelbase than the average, the prices require higher strength and stiffness, so characteristic for the Dump Truck, Dump Truc

25、k chassis are often designed to be specific. Tipper tops, including cars, subframe, hydraulic lift dump bodies, electrical are systems. </p><p>  Dump Truck lifting mechanism is the core of the Dump Truck ju

26、dge the merits of the primary indicators. </p><p>  Lifting mechanism of the type currently common are: F-type lifting mechanism to enlarge tripod, T-style tripod zoom lifting mechanism, lift cylinder, front

27、 roof lift and double roll. </p><p>  Dump Truck engine, chassis and cab of the truck are the same structure and general. </p><p>  Points after Dump Truck of the car to rollover and side tippin

28、g two, by manipulating the system control rod movement, the more common after the tipping, tipping push rod to make car, a small number of two-way is tipping. </p><p>  Distribution of high-pressure oil thro

29、ugh the valve, tubing into the lift cylinder, front-end with the cab car is safety board. </p><p>  The engine through the transmission, PTO driven hydraulic pump unit, hydraulic tipping body compartments fr

30、om the fuel tank, hydraulic pumps, distribution valves, lifting hydraulic cylinders, control valves and tubing and other components. </p><p>  Hydraulic tipping body is compartments from the fuel tank, hydra

31、ulic pumps, distribution valves, lifting hydraulic cylinders, control valves and tubing and other components. </p><p>  The engine through the transmission, PTO driven hydraulic pump unit, distribution valve

32、s for high pressure oil through the tubing into the lifting cylinder, push rod to make car rollover. More common after the rollover, by manipulating the system control rod movement, can stop the train tilted in any desir

33、ed position. Compartments use of their owner gravity and hydraulic control reset. </p><p>  Tripod enlarge Lifting Mechanism is currently the most widely used way of lifting for 8 to 40 tons of load compartm

34、ent length of 4.4 to 6 meters. Structural advantages of mature, stable lifting and low cost; drawback to the main frame on the floor inside is the closed height of the larger plane. </p><p>  Most of lift cy

35、linder form of Dump Truck used in the 6X4 on the bridge in front of each side of the second installation of a multi-cylinder (generally 3 to 4), the hydraulic cylinder directly on the pivot point on the compartment floor

36、. Twin advantages of lifting the main frame for the compartment floor and a high degree of closure on the smaller plane; disadvantage is that the hydraulic system is difficult to ensure synchronization of two hydraulic c

37、ylinders and held steady and poor students, t</p><p>  Way before the top lift of simple structure, with the main frame on the floor inside the closed surface height can be very small, vehicle stability, low

38、 pressure hydraulic system, but the first big trip at the most-cylinder, high cost. </p><p>  Double roll force cylinders good, travel less, achieve double roll; but more complex hydraulic piping, give stude

39、nts a higher incidence of rollover accidents. </p><p>  Dump Truck with the development and improvement of domestic purchasing power, Dump Truck is not in the traditional sense of what life can be dry univer

40、sal truck, from the design point of view but also according to different goods, different conditions, different is regions developed different products. This requires the user to purchase vehicles to the manufacturer for

41、 specific use. </p><p>  1. Chassis </p><p>  In the choice of chassis, generally is based on economic benefits to consider, such as: the price of the chassis, loading quality, overload capacity

42、, fuel consumption per hundred kilometers, road maintenance and so on. In addition, the user must also consider the chassis of the following parameters: </p><p> ?、貶eight of the chassis frame on the plane. G

43、eneral 6x4 chassis frame height of the upper surface of 1050 to 1200. The higher the number the greater the vehicle center of gravity, the more easily cause an overturn. The main factors affecting the value of the tire d

44、iameter, suspension layout and the main frame is cross-section height. </p><p> ?、贑hassis rear overhang. The number of Dump Trucks moves through the General Assembly, growth stability, gives students a rollo

45、ver accident caused. This value is generally between 500-1100 (except Dump Truck roll). </p><p> ?、踁ehicle matching rational use and reliable. </p><p>  1. Upload </p><p>  Currentl

46、y converted Dump Truck manufacturers was mixed, select the Dump Truck manufacturers over the selection of choice products are equally important. In addition to looking products, but also understand the capabilities of eq

47、uipment manufacturers, Dump Truck tops the design, technology and equipment is mature, service commitments, it can buy other accessories. </p><p>  Third, the lifting mechanism of choice: </p><p&g

48、t;  1. Recommended to choose a tripod for general use zoom-type Dump Truck lifting mechanism, the structure in China has a 40-year history, technology is relatively mature, suitable for carriage 4 to 6 meters in length D

49、ump Truck. </p><p>  2. Reasonable arrangement, the parts Shouli Bu exceed the capacity of components, system hydraulic smaller, in order to ensure the seal life. </p><p>  3. The choice of qual

50、ity hydraulic cylinders. Lifting hydraulic cylinder is the power unit, try to choose a quality assurance products, such as: blue post card hydraulic cylinder, the manufacturers promised lifetime warranty. </p><

51、;p>  4. Compartment of the truck longer than 6 meters generally used in multi-cylinder front-top lifting structure. </p><p>  5. Cylinder lifting structure is generally used with a wheelbase of the truck

52、3 to 4 meters. </p><p>  Fourth, selection issues to the attention of </p><p>  1. Transport large items must be selected inside the bucket. </p><p>  2. Car is longer than 5.4 mete

53、rs to pay special attention when the cars center of gravity and lifting stability. </p><p>  3. Can not be transported by special vehicles to transport coal earth. Private car coal train general height of 1.

54、6 ~ 1.9 m, length how the design of these vehicles is based on light goods (weight less than 1.2) to consider, for transporting earth and stone lifting may have poor stability, which seriously may lead to lifting a rollo

55、ver accident. </p><p>  4. Do not use the bucket car transporting silt, clay and other sticky goods, the structure of the bucket carriage of goods more difficult to remove the sticky. </p><p>  

56、5. Transport iron ore in the Dump Truck manufacturers to keep up when the statement selection, selection of the best choice for iron ore carrier. </p><p>  6. For the transportation of asphalt paving, the li

57、fting mechanism requires slow down device. </p><p>  Fifth, use and maintenance of Dump Truck </p><p>  How several common errors: </p><p>  1. Engine running, take power in the &qu

58、ot;on", lift the handle in the "lift" and Meng lift the clutch. Since leaving the sudden engagement PTO, oil pump and oil pump drive shaft causes a lot of impact load, could easily lead to early damage (us

59、ually occurred as the oil pump drive shaft damage.) High-speed operation in the engine compartment fully loaded, cold winter with high viscosity hydraulic oil under even more prominent.</p><p>  2. In the mi

60、ddle of a sudden the elevator full of lifting the handle into the "down position", when the car was not touched down, but suddenly rushed down, this will bring great impact frame, and even accidents. Although t

61、he single-acting hydraulic cylinder piston set a throttling device to ensure that the decline in the car before the end of the throttling effect have landed on the car speed is automatically slowed down, but the cars ful

62、l effect has been obvious, therefore, should try to avoid </p><p>  3. Xiewan goods, do not forget to disengage the power take off, or disengage the power take off will be driving, so the car is moving, due

63、to take power in the "engagement" position, the lift pump in the "small cycles" state No load speed for a long time operation. The so-called "small cycles" when running the oil pump oil pump

64、 hydraulic oil only in the high and low voltage circuit between the loop. In this case the hydraulic oil temperature rises quickly, easily lead to damage to pump seals, or</p><p>  4. By Meng mention car - b

65、rake suddenly unloading. Meng mentioned as the inertial force of a great car (usually the rated lifting force of 5 to 20 times), can easily cause permanent deformation of the frame, open frame car and pay for welding, bu

66、rning or destruction of oil pump seal, hydraulic cylinders and other damage damage , reduces the life of the vehicle, serious rollover accidents also occur. Therefore, when lifting the general ban truck traffic. </p&g

67、t;<p>  5. Driving power take off in the "ON" position: If "on" state (red light), the pump will continue to rotate, there is power source of the hydraulic system, which would control valve bec

68、ause the gas control misoperation caused by cars on the auto-lifting; time distribution of air control valve even in the "down" position, the oil should enter the pump, it would pump burned out. </p><

69、;p>  6. Moving to lift the handle placed in the "stop" position: At this point the hydraulic system in a closed state, the impact of the ground while driving through the lifting mechanism can be passed to ca

70、rs , some connected parts are easily damaged. So when driving down the handles is put some "down" position. </p><p>  7. In a great venue for cross slope of discharge: trunk askew when lifting, car

71、 flip axis may produce permanent deformation may occur more serious when it overturned. </p><p>  8. Goods have not been fully discharged when the use of safety rod may result in accidents, the safety pole i

72、nspection and maintenance is only used for carriages. </p><p><b>  自卸汽車</b></p><p>  自卸汽車是指以運送貨物為主且有傾卸貨廂的汽車,又稱翻斗車。</p><p>  自卸汽車的特點是其車廂可以傾斜一定的角度,使車廂內(nèi)的貨物卸出。車廂的傾斜是以自卸汽車發(fā)動機

73、的動力,通過傾卸機構(gòu)來完成的。</p><p>  自卸汽車自20世紀初出現(xiàn)以來,不斷發(fā)展,日趨完善,已成為當今貨物運輸?shù)闹饕囕v之一。自卸汽車具有高度機動性和卸貨機械化等有點,通常與鏟式裝載機、挖掘機或皮帶運輸機等配套使用,實現(xiàn)裝卸機械化,從而可以大大縮短裝卸時間,提高運輸效率并可節(jié)省勞動力,減輕勞動強度。隨著汽車制造業(yè)的發(fā)展,自卸汽車不斷采用新材料、新工藝,提高其質(zhì)量利用系數(shù),具有較大的速度范圍和較高的傳動效

74、率,控制與操縱更完善,更方便。</p><p>  一、 國內(nèi)外技術(shù)發(fā)展現(xiàn)狀</p><p><b>  1. 人性化</b></p><p>  進一步提高整車的安全性,包括車身安全性能、制動性能進一步提高,以及駕駛員操縱便利性、乘坐舒適性是目前國內(nèi)外汽車發(fā)展人性化要求的體現(xiàn),這表現(xiàn)在車身、底盤等各個方面。</p><p&

75、gt;<b> ?。?)懸架系統(tǒng)</b></p><p>  國外高檔自卸汽車如SCANIA、VOLVO等,均采用自動調(diào)節(jié)的空氣懸架,而國內(nèi)基本還是鋼板彈簧,比較好的采用的是橡膠懸架。</p><p><b>  (2)變速系統(tǒng)</b></p><p>  國外主要采用自動變速箱。國內(nèi)主要還是采用手動變速箱,也有部分廠家開

76、始試用自動變速箱來配置汽車底盤。</p><p><b>  (3)制動系統(tǒng)</b></p><p>  國外主要采用電控制系統(tǒng)(ECBS)與氣壓盤式制動器,并加裝ABS等電子調(diào)節(jié)系統(tǒng)。國內(nèi)主要還是采用鼓式制動,加裝ABS等電子制動系統(tǒng)的較少,也有廠家開始開發(fā)盤式制動。</p><p><b> ?。?)車身系統(tǒng)</b>&

77、lt;/p><p>  國內(nèi)自卸汽車的車身舒適性較歐洲車的差距還是很大的。不過高檔駕駛室,駕駛和乘坐舒適性較以前有了很大的提高。</p><p><b>  2.專用化</b></p><p>  國外自卸汽車的專用化分類越來越明顯。除了普通的工程用自卸汽車外,還 根據(jù)世紀的需求和用途,開發(fā)了專用自卸汽車。</p><p>

78、;  (1)公路撒鹽清掃自卸車</p><p>  下雪天將化雪鹽運輸至公路上,清掃道路上的積雪,灑布化雪鹽。</p><p> ?。?)污染類流體運輸自卸車</p><p>  實現(xiàn)污染類流體的收集、運輸和傾卸,可以更好地保護汽車底盤,適用于道路鋪設(shè)及工程施工的沙石材料運輸。</p><p>  國內(nèi)自卸汽車的專業(yè)化分類不是很明顯,目前國內(nèi)

79、的自卸汽車主要還是用于工程建設(shè)、礦山開采、煤炭運輸?shù)?,其專業(yè)化分類程度較國外還有較大的差距。</p><p><b>  3.結(jié)構(gòu)優(yōu)化</b></p><p>  歐洲高強鋼材料自卸車常選用U形或框架式車廂結(jié)構(gòu),其優(yōu)點主要有:自重輕、載重大、能裝載更多的有效載荷、間接提高了裝載效率;降低油耗、重心低、穩(wěn)定性好、舉升時貨物更易劇中、便于卸貨;整體式承載,沒有或只有很少的

80、加強筋,焊接量小;外觀設(shè)計較為現(xiàn)代化,外表面有大的平面,便于粘貼廣告或其它圖案。歐洲專用車上非常廣泛地采用塑料制作的工具箱、擋泥罩。塑料材料具有一定的韌性、耐低溫和抗沖擊性能,不易脆裂,同時質(zhì)量輕、造型美觀,在輕量化的進程中發(fā)揮著重要的作用。</p><p>  國內(nèi)也有一部分廠家技術(shù)水平較高,通過結(jié)構(gòu)的變化降低自重,而且不降低車廂性能,主要是采用了框架式車廂結(jié)構(gòu)。</p><p>  出

81、于成本和加工工藝方面考慮,國內(nèi)的自卸車仍然以普通鋼材、鋼板為主要材料。</p><p><b>  4.環(huán)保性</b></p><p>  隨著整個世界對環(huán)境保護的日益加強,各國對車輛的環(huán)保性要求也越來越嚴格。自卸汽車裝載貨物的密封性要求也越來越受重視。</p><p>  汽車發(fā)動機技術(shù)代表了一個國家的工業(yè)水平。歐洲發(fā)達國家的汽車尾氣排放達到

82、歐V的標準,而國內(nèi)卡車的要求目前是國Ⅲ標準,國內(nèi)與國外還有非常大的差距,而且,降低汽車排放的關(guān)鍵技術(shù)只被為數(shù)不多的幾個國家所掌握,中國還有很大的技術(shù)跟進及發(fā)展過程。環(huán)保要求的進一步提高,對自卸汽車的密封性要求也提到了日程,國內(nèi)外均采用了多種方法來防止自卸汽車的貨物撒落。國外自卸汽車的專業(yè)化分類也有利于保護環(huán)境,如污染類流體運輸自卸車的開發(fā)和使用,但大多數(shù)福哦家主要采用了自卸汽車車廂加蓋的方式。自卸汽車的密封蓋主要有兩種:一種為篷布軟蓋,

83、一種為金屬硬蓋。因此,國外的車輛使用一般不超載,貨物基本不超出車廂的上沿。而國內(nèi)的自卸汽車則兩種都有,城市環(huán)保要求高的多數(shù)采用金屬蓋,密封性較好,但成本高;環(huán)保要求較低的多數(shù)采用軟蓋,密封性差一些,但成本低。</p><p>  二、 主要結(jié)構(gòu)及功能</p><p>  自卸汽車由汽車底盤和上裝兩大部分組成,底盤大多采用定型汽車二類底盤。由于自卸車軸距比一般貨車要短,車價要求有較高的強度和

84、剛度,所以針對自卸車特點,往往設(shè)計成專用自卸車底盤。自卸車上裝包括車廂、副車架、液壓舉升傾卸機構(gòu)、電氣系統(tǒng)等。</p><p>  舉升機構(gòu)是自卸車的核心,是判別自卸車優(yōu)劣的首要指標。 </p><p>  舉升機構(gòu)的型式目前國內(nèi)常見的有:F式三角架放大舉升機構(gòu)、T式三角架放大舉升機構(gòu)、雙缸舉升、前頂舉升和雙面?zhèn)确?lt;/p><p>  自卸車的發(fā)動機、底盤及駕駛室

85、的構(gòu)造和一般載重汽車相同。 </p><p>  自卸車的車廂分后向傾翻和側(cè)向傾翻兩種,通過操縱系統(tǒng)控制活塞桿運動,后向傾翻較普遍,推動活塞桿使車廂傾翻,少數(shù)雙向傾翻。 </p><p>  高壓油經(jīng)分配閥、油管進入舉升液壓缸,車廂前端有駕駛室安全防護板。</p><p>  發(fā)動機通過變速器、取力裝置驅(qū)動液壓泵,車廂液壓傾翻機構(gòu)由油箱、液壓泵、分配閥、舉升液壓缸、

86、控制閥和油管等組成。 </p><p>  車廂液壓傾翻機構(gòu)由油箱、液壓泵、分配閥、舉升液壓缸、控制閥和油管等組成。 </p><p>  發(fā)動機通過變速器、取力裝置驅(qū)動液壓泵,高壓油經(jīng)分配閥、油管進入舉升液壓缸,推動活塞桿使車廂傾翻。以后向傾翻較普遍,通過操縱系統(tǒng)控制活塞桿運動,可使車廂停止在任何需要的傾斜位置上。車廂利用自身重力和液壓控制復(fù)位。</p><p>

87、  三角架放大式舉升機構(gòu)是目前國內(nèi)使用最多的一種舉升方式,適用載重量8~40噸,車廂長度4.4~6米。優(yōu)點為結(jié)構(gòu)成熟、舉升平穩(wěn)、造價低;缺點為車廂底板與主車架上平面的閉合高度較大。 </p><p>  雙缸舉升形式大多用在6X4自卸車上,是在第二橋前方兩側(cè)各安裝一支多級缸(一般為3~4級),液壓缸上支點直接作用在車廂底板上。雙缸舉升的優(yōu)點為車廂底板與主車架上平面的閉合高度較小;缺點是液壓系統(tǒng)很難保證兩液壓缸同步

88、,舉生平穩(wěn)性較差,對車廂底板的整體剛度要求較高。 </p><p>  前頂舉升方式結(jié)構(gòu)簡單、車廂底板與主車架上平面的閉合高度可以很小,整車穩(wěn)定性好,液壓系統(tǒng)壓力較小,但前頂多級缸行程較大,造價很高。 </p><p>  雙面?zhèn)确簤焊资芰^好,行程較小,可實現(xiàn)雙面?zhèn)确?;但液壓管路較復(fù)雜,舉生翻車事故發(fā)生率較高。</p><p>  隨著自卸汽車的發(fā)展和國內(nèi)購買能

89、力的提高,自卸車已經(jīng)不是傳統(tǒng)意義上的什么活都可以干的萬能自卸車,從設(shè)計角度講也是按不同的貨物、不同工況、不同地區(qū)開發(fā)不同的產(chǎn)品。這就要求用戶在購買車輛時要向廠家提供具體使用情況。</p><p><b>  1.底盤</b></p><p>  在選擇底盤時,一般是按經(jīng)濟效益來考慮的,比如:底盤的價格、裝載質(zhì)量、超載能力、百公里油耗、養(yǎng)路費等。除此之外,用戶還要考慮底

90、盤的如下參數(shù): </p><p> ?、?底盤車架上平面離地高度。一般6x4底盤車架上平面離地高度為1050~1200。該數(shù)值越大整車重心越高,越容易造成翻車。影響該數(shù)值的因素主要是輪胎直徑、懸掛的布置和主車架截面高度。 </p><p> ?、?底盤后懸。該數(shù)值過大會影響自卸車舉生穩(wěn)定性,造成舉生翻車事故。此數(shù)值一般在500-1100之間(側(cè)翻自卸車除外)。 </p>&l

91、t;p> ?、?整車匹配合理、使用可靠。 </p><p><b>  2.上裝</b></p><p>  目前自卸車改裝廠家魚龍混雜,選擇自卸車時選擇廠家比選擇產(chǎn)品同樣重要。除看產(chǎn)品外,還要了解廠家的設(shè)備能力、自卸車上裝的設(shè)計、工藝裝備是否成熟、售后服務(wù)承諾、配件是否能買到等。</p><p>  三、 舉升機構(gòu)的選擇: </p

92、><p>  1.一般用途自卸車建議選擇三角架放大式舉升機構(gòu),該結(jié)構(gòu)在我國已有40年歷史,技術(shù)比較成熟,適合車廂長度4~6米的自卸車。 </p><p>  2.合理布置,各零部件受力不會超過零部件的承受能力,系統(tǒng)油壓較小,以保證各密封件的使用壽命。 </p><p>  3.選擇優(yōu)質(zhì)液壓缸。液壓缸是自卸車舉升的動力部件,盡量選擇有質(zhì)量保證的產(chǎn)品,比如:青專牌液壓缸,廠

93、家承諾終身保修。 </p><p>  4.車廂長度大于6米的自卸車一般選用多級缸前頂式舉升結(jié)構(gòu)。 </p><p>  5.雙缸舉升結(jié)構(gòu)一般用于軸距為3~4米的自卸車。 </p><p>  四、 選型時要注意的問題</p><p>  1.運輸大塊物品必須選用鏟斗車廂。 </p><p>  2.車廂長度大于5.4

94、米時要特別注意車廂重心高度和舉升穩(wěn)定性。 </p><p>  3.不能用運煤專用車運送土石方。一般運煤專用車的車廂高度在1.6-1.9米,長度如何這類車輛設(shè)計時是按輕質(zhì)貨物(比重小于1.2)考慮的,用于運送土石方時可能有舉升穩(wěn)定性差的問題,嚴重者可引起舉升翻車事故。 </p><p>  4.不要用鏟斗車廂運送淤泥、粘土等粘稠貨物,鏟斗車廂的結(jié)構(gòu)使粘稠貨物更不容易卸下。 </p&g

95、t;<p>  5.運輸鐵礦粉的自卸車選型時要跟廠家聲明,最好選擇鐵礦粉選用運輸車。 </p><p>  6.用于鋪路瀝青運輸時,舉升機構(gòu)要求有慢降裝置。 </p><p>  五、 自卸車使用和維護</p><p>  常見的幾種錯誤操作方法: </p><p>  1.發(fā)動機運轉(zhuǎn),取力器位于“接通”,升降手柄位于“舉升”而

96、猛抬離合器。由于突然的接合而使取力器、油泵傳動軸及油泵引起很大的沖擊載荷,易造成早期損壞(一般多發(fā)生為油泵傳動軸損壞)。在發(fā)動機高速運轉(zhuǎn),車廂滿載,冬季寒冷液壓油粘度高的情況下更為突出。 </p><p>  2.在滿載舉升中途突然將升降手柄推向“下降位置”,這時車廂不是徐徐降落,而是猛然沖下,這會給車架帶來很大的沖擊力,甚至?xí)l(fā)生意外事故。盡管單作用活塞式液壓缸設(shè)置有節(jié)流裝置,以保證在車廂下降終了前產(chǎn)生節(jié)流作用

97、使車廂降落速度自動減慢,但對于滿載的車廂效果已不明顯,因此,應(yīng)盡量避免上述操作,如有特殊情況需要也必須小心操作,盡量放慢降落速度,必須切忌勿猛然將車廂落到底。 </p><p>  3.卸完貨后,不脫開取力器或忘記脫開取力器便行車,這樣汽車在行駛時,由于取力器處于“接合”位置,舉升油泵則在“小循環(huán)”狀態(tài)下高速長時間無負荷運轉(zhuǎn)。所謂“小循環(huán)”即油泵運轉(zhuǎn)時液壓油只在油泵高、低壓回路之間循環(huán)。這種情況下液壓油油溫上升很

98、快,易造成油泵油封的損壞,甚至發(fā)生油泵“燒死”的現(xiàn)象; 另外在高速行車時,油泵傳動軸也會在過高的離心力作用下導(dǎo)致早期損壞。更嚴重的是油泵的運轉(zhuǎn)意味著液壓系統(tǒng)有動力源, 在行車過程中會因各種原因而出現(xiàn)車廂自動升起的事故。 因此,在卸完貨行車時,必須及時脫開并確認取力器已經(jīng)脫開再使車輛行駛。 </p><p>  4.利用猛提車—猛剎車卸貨。由于猛提車的慣性力很大(一般是額定舉升力的5~20倍),極易造成車架永久變形

99、、車廂和付車架開焊、燒油泵或破壞密封圈、破壞液壓缸等損害,車輛的使用壽命降低,嚴重者還會出現(xiàn)翻車事故。所以一般自卸車禁止舉升時行車。 </p><p>  5.行駛時取力器在"接通"位置:若在"接通"狀態(tài)(紅燈亮著),則油泵將繼續(xù)轉(zhuǎn) 動,液壓系統(tǒng)就有動力源,這樣就會因為在氣控操縱閥上的誤操作而引起車廂自動舉升; 此時氣控分配閥即使在"下降"位置,油也

100、要進入油泵,這樣會使油泵燒壞。 </p><p>  6.行駛時將升降手柄置于“中?!蔽恢茫捍藭r液壓系統(tǒng)處于封閉狀態(tài),行車時地面的沖擊可以通過舉升機構(gòu)傳遞到車廂,極易損壞某些聯(lián)結(jié)部件。所以行駛時一定要將升降手柄置于“下降”位置。 </p><p>  7.在有很大橫向坡度的場地卸貨:舉升時車箱歪斜,車廂翻轉(zhuǎn)軸可能產(chǎn)生永久變形,更嚴重者可能發(fā)生翻車時故。 </p><p&

溫馨提示

  • 1. 本站所有資源如無特殊說明,都需要本地電腦安裝OFFICE2007和PDF閱讀器。圖紙軟件為CAD,CAXA,PROE,UG,SolidWorks等.壓縮文件請下載最新的WinRAR軟件解壓。
  • 2. 本站的文檔不包含任何第三方提供的附件圖紙等,如果需要附件,請聯(lián)系上傳者。文件的所有權(quán)益歸上傳用戶所有。
  • 3. 本站RAR壓縮包中若帶圖紙,網(wǎng)頁內(nèi)容里面會有圖紙預(yù)覽,若沒有圖紙預(yù)覽就沒有圖紙。
  • 4. 未經(jīng)權(quán)益所有人同意不得將文件中的內(nèi)容挪作商業(yè)或盈利用途。
  • 5. 眾賞文庫僅提供信息存儲空間,僅對用戶上傳內(nèi)容的表現(xiàn)方式做保護處理,對用戶上傳分享的文檔內(nèi)容本身不做任何修改或編輯,并不能對任何下載內(nèi)容負責(zé)。
  • 6. 下載文件中如有侵權(quán)或不適當內(nèi)容,請與我們聯(lián)系,我們立即糾正。
  • 7. 本站不保證下載資源的準確性、安全性和完整性, 同時也不承擔(dān)用戶因使用這些下載資源對自己和他人造成任何形式的傷害或損失。

評論

0/150

提交評論