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中 國 礦 業(yè) 大 學
本科生畢業(yè)論文
姓 名: 周春雷 學 號:21040293
學 院: 應(yīng)用技術(shù)學院
專 業(yè): 機械工程及自動化
論文題目: 刮板輸送機設(shè)計
專 題:
指導教師: 王啟廣 職 稱: 副教授
2008 年 6月 徐州
中國礦業(yè)大學畢業(yè)論文任務(wù)書
學院 應(yīng)用技術(shù)學院 專業(yè)年級 機自04-3班學生姓名 周春雷
任務(wù)下達日期:2008年3月16日
畢業(yè)論文日期:2008年3月20日至2008年6月12日
畢業(yè)論文題目:刮板輸送機設(shè)計
畢業(yè)論文專題題目:
畢業(yè)論文主要內(nèi)容和要求:
設(shè)計參數(shù):
設(shè)計長度 200m
生產(chǎn)能力 1000t/h
鏈 速 1m/s
要求:
(1)刮板輸送機的傳動方案設(shè)計;
(2)減速器的設(shè)計;
(3)完成主要傳動組件,零件的工作圖設(shè)計;
(4)編寫完成設(shè)計計算說明書。
院長簽字: 指導教師簽字:
中國礦業(yè)大學畢業(yè)論文指導教師評閱書
指導教師評語(①基礎(chǔ)理論及基本技能的掌握;②獨立解決實際問題的能力;③研究內(nèi)容的理論依據(jù)和技術(shù)方法;④取得的主要成果及創(chuàng)新點;⑤工作態(tài)度及工作量;⑥總體評價及建議成績;⑦存在問題;⑧是否同意答辯等):
成 績: 指導教師簽字:
年 月 日
中國礦業(yè)大學畢業(yè)論文評閱教師評閱書
評閱教師評語(①選題的意義;②基礎(chǔ)理論及基本技能的掌握;③綜合運用所學知識解決實際問題的能力;③工作量的大?。虎苋〉玫闹饕晒皠?chuàng)新點;⑤寫作的規(guī)范程度;⑥總體評價及建議成績;⑦存在問題;⑧是否同意答辯等):
成 績: 評閱教師簽字:
年 月 日
中國礦業(yè)大學畢業(yè)論文評閱教師評閱書
評閱教師評語(①選題的意義;②基礎(chǔ)理論及基本技能的掌握;③綜合運用所學知識解決實際問題的能力;③工作量的大??;④取得的主要成果及創(chuàng)新點;⑤寫作的規(guī)范程度;⑥總體評價及建議成績;⑦存在問題;⑧是否同意答辯等):
成 績: 評閱教師簽字:
年 月 日
中國礦業(yè)大學畢業(yè)論文答辯及綜合成績
答 辯 情 況
提 出 問 題
回 答 問 題
正 確
基本
正確
有一般性錯誤
有原則性錯誤
沒有
回答
答辯委員會評語及建議成績:
答辯委員會主任簽字:
年 月 日
學院領(lǐng)導小組綜合評定成績:
學院領(lǐng)導小組負責人:
年 月 日
中國礦業(yè)大學2008屆畢業(yè)生畢業(yè)設(shè)計 第17頁
英語翻譯
英文原文
Scraper conveyor of the status quo and development trend of technology
Abstract: The Face scraper conveyor of the machine and its head, tail, the central trough, ring linked, soft-start devices, components of the technical status quo and development trend, and made China's development scraper conveyor Trend.
Key words: scraper conveyor with two, components, development trends.
In recent years, with high yield and high efficiency of the rapid development of intensive mine, the coal mine in a mine to achieve a high degree of concentration of wells a production model. Face the long arm as the main transportation equipment, the scraper conveyor transport capability mainly by high yield and high efficiency of the production capacity of the mine to decide, but also determines the scraper conveyor trend of development.
1 Technology status
Since the 1980s, both at home and abroad scraper conveyor to the large volume, long distance, high-power, high-intensity, high reliability and long life direction. At present, the largest foreign Fully-face scraper conveyor to transport volume has reached 6000 t / h, installed power 4 × 800kW, distance 450 m. Domestic independent research and development of the scraper conveyor transport volume has reached 3500 t / h, installed power 3 × 700kW, distance 300 m. With God East, and other large coal base 400 m face the emergence of China-made scraper conveyor will be moving in the direction of more large-scale. However, volume, distance and the increase of power by many factors. First of all, the height of the central trough should not be too high, otherwise they will be affected with coal effect. Second, the conveyor's length should not be too long, Will reduce the rate of advance. Then the most important factors is also key components of the technical performance and life expectancy. Therefore, the scraper conveyor to the development of large-scale, high-performance components of the R & D will become the next scraper conveyor focus on the development, soft-start technology, the status of testing, running state control the use of mechanical and electrical integration technology will be Scraper conveyor into the future development of an important symbol
2 Yuan parts of the technical status quo
2.1 Head
With the fully mechanized coal face of rapidly increasing production apacity, scraper conveyor-unloading has been difficult to meet the requirements of domestic and foreign large volume of heavy scraper conveyor adopt cross-lateral institutions unloaded, the agency after several generations of improvements in the ability to offload , Efficiency, life and other aspects of a big increase. At the same time, unloading a high degree of reduced support for the fully mechanized coal mining has brought convenience.
2.2 Tail
For long distance, high-power scraper conveyor, the chain tension need greater flexibility trip, both at home and abroad using retractable tail, and is divided into manual and automatic tight chain tight chain. Manual tight chain system is regularly measured by the chain of artificial tension, stretching the tail, which can not guarantee the chain will always be in the best state of tension and the automatic system is the ideal tight chain of tension, as shown in Figure 1. The system in the chain and the nose, tail drive sprocket chain from the bottom, a tension sensor placement, in accordance with the actual chain of take-up tension control the fuel tank. This automatic use of the tight chain, conveyor chain operation will always maintain the best state of tension, to extend the life of the chain, reducing downtime.
Figure 1 automatically tensioning system
2.3 Sprocket components
Sprocket scraper conveyor components is the key component, and its development trend of improving the reliability of sprocket components, the price increase sprocket accuracy, improving heat treatment process to extend the life of sprocket.
At present sprocket components in the structure of use of double-row tapered roller bearings, light oil lubrication, nose and tail of the sprocket components are the same, through different gear reducer coupling connection with the replacement of underground Reducer, not demolition; sprocket using high-strength alloy steel, of quenching the hardness to eat HRC55, effective hardening depth of 10 mm and above, the service life of up to 400 to 5 million t of the media.
In addition, from sprocket on the tooth to be improved, for example, a company design the GR-sprocket and there is great difference between conventional sprocket, which always has three sprocket tooth led the entire load. 3 tooth contact will inevitably reduce the wear chain and sprocket, thereby extending the life of the chain and sprocket, reducing the chain elongation, power transmission efficiency is higher.
2.4 Soft-start devices
Foreign advanced conveyor transmission use of soft-start technology, in scraper conveyor on the successful use of the soft-start main valve control device-filled hydraulic coupler, CST controllable start and the exchange of electrical transmission system, such as Frequency Control . Because there is no domestic mature technologies and products, the China-made high-power scraper conveyor used in soft-start device for all imported products. Figure 2 was developed by Germany-filled hydraulic valve control DTP coupler.
2.4.1-filled hydraulic valve control coupled with the principal technical characteristics
⑴ can achieve the empty scraper conveyor start and overload protection;
Change can be achieved through
⑵ scraper conveyor the frequent start, without limitation start frequency;
⑶ through hydraulic coupler divisions will also re-order the multi-drive can be achieved under the load balancing;
⑷ slow post-mortem can be linked;
⑸ dual-chamber design, compact, power transmission components without mechanical contact, high reliability.
⑹ with water as a working fluid, safe and convenient and cheap, through pipes or water supply, drainage tube through the pump row, row of pressure from the main hydraulic motor-driven cycle produced by the pilot of the portfolio directly to the valve To control the water cycle;
⑺ without affecting the power transmission circumstances, * Change to heat through.
Figure 2 DTP-valve-controlled oil-filled hydraulic coupler
2.4.2CST controlled transmission system activated the main technical characteristics
⑴ in any load can track any launch curve, the speed of plus or minus any adjustment;
⑵ relative speed hydraulic coupler, the transmission efficiency;
⑶ an arbitrary controlled under the conditions of parking capacity;
⑷ can be driven to achieve more balance of power between the high-precision, balance accuracy up to 98 percent;
⑸ conveyor of all mechanical, electrical system overload protection, the protection system fast response;
⑹ be running low on time, and cashing in on the trend post-mortem chain;
⑺ scene debugging simple, it is easy to modify the parameters online and debugging.
2.4.3 AC motor technology the main technical characteristics
⑴ and other soft-start mode compared to the full realization of electrical soft-start control, scraper conveyor drive system and power supply system to maximize the simplification;
⑵ start-up time can be loaded with self-regulation;
⑶ achieved a scraper conveyor loaded with empty and the smooth start-up;
⑷ significantly reduce the starting current and improve the quality of electricity supply grid, power grid to reduce impact.
2.5 Central groove
Central trough conveyor of the whole face of the trunk, its life is a measure of an important indicator of life. At present the central trough use of Σ trough-shaped cross section for the whole cast back cover welding structure, life expectancy has reached 10 million t. To further improve the service life of the major manufacturers of domestic and foreign central trough of form, structure and materials have done a great deal of research. Such as Germany of a company through research and development, be that in different sections of the mine shafts for a large number of Central Test and eventually found, and Σ trough-shaped cross section for comparison, curved section slot for the scraper to help with the trough in contact with the side of the small, thereby reducing friction and reduce power consumption, extend the central slot and scraper life. Σ scraper and arc-shaped cross section and the section for surface trough comparison shown in Figure 3.
Figure 3 scraper and Σ arc-shaped cross section and the section for surface trough comparison
From top to bottom for a slot on the design, shown in Figure 4, from top to bottom slot for the same, you can choose any thickness and width of the plate in the central trough design makes for greater flexibility. Slot for each board and the central slot between the two Weld, the central side of the trough of four seam, only on the inside of the tank to help withstand the wear and tear a seam, even if it was polished welds , The central trough can maintain a high degree of stability.
Figure 4 4-steel tank to help design and wear contour
Help create a slot on the Rolling materials, steel rolling on the surface than the smooth casting of steel, small friction. Central tank plate using high-strength steel hardening Wear-resistant, wear little. Rolling in the central trough lateral welding dumbbell Block, will not help reduce the thickness of groove. Forging dumbbell on the design and ensure that the central trough Yaling not Block damage, and the youngest is basically breaking strength of 1.5 times the dumbbell, so the fault is always the first dumbbell.
Another trough of the central structure of the tank from top to bottom-of-duplication, this form can be set from top to bottom groove and the failure of different conditions for different structural design and material selection, and easy on the replacement tank, will help improve strength and Life. The central trough in the form of SGZ880 / 2 × 400-type double-stranded in the cross-side dumping in the face scraper conveyor has been successfully applied.
2.6 Ring linked
Circle as a scraper conveyor chain of traction, its tensile strength directly related to the reliability of. At present, China's largest ring linked to φ42 mm × 146mm compact chain, tensile strength of 2270 kN, the largest foreign ring linked to φ48 mm × 152mm compact chain, tensile strength of 3550 kN. With the ring linked the increasing size of the central trough of higher and higher, conveyor magnificent performance declined, the gateway if not thorough clean-up will also affect passage of conveyor. So ring linked the direction of development is to improve tensile strength and reduce the high degree of Central legislation.
2.6.1 Materials and Technology
In order to improve the roundabout chain of tensile strength, the current foreign Grade C and D-linked ring in the large-sized materials with 23 MnNiCrMo54, 23MnNiCrMo54 and 23 MnNiCrMo64 scouring steel, tensile strength limit ≥ 1600 ~ 1800 MPa. Welding Technology: the use of advanced welding equipment, welding and the use of flash returns processing technology, successfully resolved the surfacing of the process of overheating, such as a burning issue. In quality testing, the use of scanning stretch fracture fracture of cables used to pre-tension ring linked to strengthen technology, greatly enhancing the carrying capacity and fatigue.
2.6.2 form and geometry
In 1985 the first to create a company 38 mm × 137mm flat chain. Flat is linked each of the chain is still ring-Central, Central was "squeezed" the flat ring. Flat chain link sliding work to reduce the size of the increase in the chain of slot pressure on the units and improve the legislation of the Central wear resistance; reduce its high level of the chain more easily through the sprocket, but can also reduce the capacity of power transmission and Bays of a high degree. Modern high-performance conveyor are generally involved in supporting a flat chain.
Figure 5 conventional chain and a new wide-body linked flat
In 2003, the company has developed a wide-body at a flat linked, as shown in Figure 5. It is a high-intensity, low-chain, has the following characteristics:
⑴ using this chain can reduce the high scraper chain, thereby reducing the central trough height, eventually reduce the use of high-mining, coal mining to meet thin.
⑵ using this chain can reduce the use of power, or power in the same circumstances, increase the length of face, it will greatly reduce the workload of opening up, reducing the number of face move.
⑶ this forging of wide-body flat link chain has increased the contact area, can improve the chain link at the same time reduce the intensity of the wear and helps to maintain the rigidity of chain link. Such as a flat 42 mm chain can take 2 × 855kW of installed power, and 50 mm wide-body flat can be linked up to 3 × 1000kW bear the installed power.
2.6.3 intelligent conveyor chain
As unable to accurately predict the failure of the chain, according to conventional practices are generally ahead of the replacement of the chain. In 2005 a company with a number of research institutes to study the development of a conveyor chain-detection system, as shown in Figure 6. This is a combination of integrated sensor technology of intelligent conveyor chain, it will stress the chain of real-time record, the help of micro-electronics technology devices, from computers that the chain of life remaining before the fracture. It also can detect the chain of preload, is conducive to life during the period in the chain to achieve the best use of state, improve safety and avoid accidents.
2.7 The link chain
The link chain-rings are used for the link chain and ring for legislation to link the two in recent years has tended to adopt legislation to link the ring, then such a chain link through the sprocket and not linked A round of contacts, so there will not be worn.
Blockmaster the link chain is a new legislation for a flat linked to the Central chain link shown in Figure 7, because of their extreme length of closure, at the time of installation without relaxation chain; their innovative design concept, two-way installation, do not have to consider the direction of transmission, There is the possibility of anti-loaded, the link chain block in central lock can be avoided chain kink, but also increased the strength of the link chain, such as 42 mm × 146mm Blockmaster the link chain of broken Rally of 2500 kN.
Figure 6 smart conveyor chain
2.8 High-power transmission gear
Scraper conveyor of the low-speed transmission is characterized by heavy, impact resistance, small in size but poor lubrication and cooling. In order to obtain high-performance gear transmission device, to be constantly raise the level of product and manufacturing standards involved.
Figure 7 Blockmaster the link chain
2.8.1 raising the level of design
Raise design standards to improve the design means first of all, the use of advanced design techniques. At present, some companies developed based on the load and deformation of the tooth contour design and calculation software and books used in high gear shift, with the bending stress on the tooth for finite element analysis to improve the shape of teeth with the transition to full gear in case meshing State be greatly improved and increased contact with strength,elasticity and the use of finite element of the planetary gear transmission mechanism for load analysis, contained both the structure more scientific and rational, adopt a flexible flow of dynamic pressure lubrication analysis of gear mating area of friction and heat Film state. The advanced design of a gear transmission, gear designed to meet the high technical indicators.
2.8.2 raising the level of manufacturing
Scraper conveyor gear more than a surface treatment of advanced hardening of low carbon steel materials, the hardening process are: carburizing, nitrogen and surface hardening. With the increase in power transmission gear, the relative size decreases, Chilian contact stress and teeth with a substantial increase in bending stress. Gear crystal material between the impurities often become the source of fatigue crack initiation. At present, the major international manufacturers scraper conveyor widely used vacuum smelting furnace of the more high-quality low-carbon steel alloy gear. Gear heat treatment using computer monitoring and control equipment carburizing atmosphere, and strictly monitor the furnace temperature, carbon potential, control gear and equipment parts used mainly CNC machining centers manufacturing, processing benefit substantially improve accuracy, domestic and foreign companies gear manufacturers in China can reach a GB100095 - 88 "involute gear machining accuracy" standard 6-6-5 level and above.
3 China scraper conveyor direction of development
With coal mine production of intensive development, has a long wall face fully mechanized coal mining equipment and technology has been to the high-end development, to meet the production capacity, a high degree of automation, safety and reliability of production requirements. At present, China's scraper conveyor of the design and manufacture close to the level of similar foreign models, but in the life of key components, reliability and innovation in such areas as compared with foreign countries there are still many gaps, particularly soft-start, overload protection And the chain automatically tensioning device, such as high-end technology products.
中文譯文
工作面刮板輸送機技術(shù)現(xiàn)狀與發(fā)展趨勢
摘要:闡述了工作面刮板輸送機整機及機頭、機尾、中部槽、圓環(huán)鏈、軟啟動裝置等元部件的技術(shù)現(xiàn)狀與發(fā)展趨勢,并提出了我國刮板輸送機的發(fā)展方向。
關(guān)鍵詞:刮板輸送機;元部件;技術(shù)現(xiàn)狀;發(fā)展趨勢。
近年來隨著高產(chǎn)高效集約化礦井的迅速發(fā)展,煤礦都在爭取實現(xiàn)一礦一井一面的高度集約化生產(chǎn)模式。作為長臂工作面的主要運輸設(shè)備,刮板輸送機的輸送能力主要由高產(chǎn)高效礦井的生產(chǎn)能力來決定,同時也決定了刮板輸送機的發(fā)展趨勢。
1整機技術(shù)現(xiàn)狀
20世紀80年代以來,國內(nèi)外刮板輸送機都在向大運量、長運距、大功率、高強度、長壽命與高可靠性方向發(fā)展。目前,國外綜采最大的工作面刮板輸送機,去運量已達6000t/h,裝機功率4×800kW,運距450m。國內(nèi)自主研發(fā)的刮板輸送機運量已達3500t/h,裝機功率3×700kW,運距300m。隨著神東等大型煤炭基地400m工作面的出現(xiàn),國產(chǎn)刮板輸送機將朝著更大型的方向發(fā)展。但是運量、運距和功率的增大受到諸多因素的限制。首先,中部槽的高度不宜太高,否則會影響裝煤效果。其次,輸送機的長度也不宜太長,會降低推進速度。然后最主要的影響因素還在于關(guān)鍵元部件的技術(shù)性能和壽命。所以,在刮板輸送機向大型化發(fā)展的同時,高性能元部件的研發(fā)將成為今后刮板輸送機的發(fā)展重點,軟啟動技術(shù)、工況檢測、運行狀態(tài)控制等機電一體化技術(shù)的運用將成為今后刮板輸送機發(fā)展的重要標志。
2元部件的技術(shù)現(xiàn)狀
2.1機頭部
隨著綜采工作面的生產(chǎn)能力迅速提高,刮板輸送機端卸載已經(jīng)難以滿足要求,國內(nèi)外大運量重型刮板輸送機均采用交叉?zhèn)刃遁d機構(gòu),該機構(gòu)經(jīng)過幾代改進,在卸載能力、效率、壽命等方面都有了很大的提高。同時,卸載高度的降低也為綜采配套帶來了便利。
2.2機尾
對于長運距、大功率刮板輸送機,鏈條張緊需要較大的伸縮行程,目前國內(nèi)外均采用可伸縮機尾,并分為手動緊鏈系統(tǒng)和自動緊鏈系統(tǒng)。手動緊鏈系統(tǒng)是靠人工定時測量鏈條張力,伸縮機尾,所以不能保證鏈條始終處于最佳張緊狀態(tài);而自動緊鏈系統(tǒng)才是理想的張緊方式,如圖1所示。該系統(tǒng)在鏈條與機頭、機尾驅(qū)動鏈輪分離后的鏈道下方安置有張力傳感器,根據(jù)鏈條的實際張力控制張緊油缸。使用了這種自動緊鏈系統(tǒng),輸送機運行時鏈條將始終保持最佳張緊狀態(tài),延長了鏈條的使用壽命,縮短了停機時間。
2.3鏈輪組件
鏈輪組件是刮板輸送機的關(guān)鍵元件,其發(fā)展趨勢時提高鏈輪組件的可靠性,提高鏈輪的價格精度,改進熱處理工藝,延長鏈輪的使用壽命。
圖1自動張緊系統(tǒng)
目前鏈輪組件在結(jié)構(gòu)上多采用雙列圓錐滾子軸承,稀油潤滑,機頭和機尾的鏈輪組件是一樣的,通過不同的齒輪聯(lián)軸器與減速器聯(lián)接,在井下更換時不用拆卸減速器;鏈輪采用高強度合金鋼,吃面淬火硬度達到HRC55,有效硬化層深度達10mm以上,使用壽命可達到400~500萬t過媒量。
另外,從鏈輪的齒形上加以改進,例如,某公司設(shè)計的GR型鏈輪與常規(guī)鏈輪就有很大區(qū)別,這種鏈輪始終有3各輪齒帶動整個載荷。3個輪齒接觸必然會降低鏈輪和鏈條的磨損,從而延長鏈輪和鏈條的使用壽命,減小鏈條伸長率,功率傳輸效率也較高。
2.4軟啟動裝置
國外先進的輸送機傳動裝置多采用軟啟動技術(shù),目前在刮板輸送機上成功使用的軟啟動裝置主要有閥控充液式液力耦合器、CST可控啟動傳輸系統(tǒng)和交流電機變頻調(diào)速等。因國內(nèi)尚無成熟的技術(shù)和產(chǎn)品,所以國產(chǎn)大功率刮板輸送機采用的軟啟動裝置全部為進口產(chǎn)品。圖2為德國研制的DTP閥控充液式液力耦合器。
圖2DTP閥控充液式液力耦合器
2.4.1閥控充液式液力耦合器的主要技術(shù)特點
⑴可以實現(xiàn)刮板輸送機的空載啟動和過載保護;
⑵通過換水可以實現(xiàn)刮板輸送機的頻繁啟動,而不必限制啟動頻率;
⑶通過告便液力耦合器的重也順序可以實現(xiàn)多機驅(qū)動下的負載平衡;
⑷可以實現(xiàn)慢速驗鏈;
⑸雙腔設(shè)計,結(jié)構(gòu)緊湊;功率傳遞部件無機械接觸,可靠性高。
⑹以清水作為工作液,安全方便而且廉價,可以通過水管或水箱供水,通過排液泵管排水,排液壓力由主電機帶動的液力循環(huán)產(chǎn)生,通過本安型先導組合閥直接對 水循環(huán)進行控制;
⑺在不影響功率傳輸?shù)那闆r下,通過換水來散熱。
2.4.2CST可控啟動傳輸系統(tǒng)的主要技術(shù)特點
⑴在任意載荷下可以跟蹤任何啟動曲線,加減速度任意調(diào)節(jié);
⑵相對調(diào)速型液力耦合器而言,傳動效率高;
⑶具有任意條件下的可控停車能力。
⑷可實現(xiàn)多點驅(qū)動之間高精度的功率平衡,平衡精度可達98%;
⑸對輸送機所有機械、電器系統(tǒng)提供過載保護,保護系統(tǒng)響應(yīng)速度快;
⑹可以上時間低速運行,實現(xiàn)免俗驗鏈;
⑺現(xiàn)場調(diào)試簡單,可以很方便地在線進行參數(shù)修改與調(diào)試。
2.4.3交流電機變頻調(diào)速技術(shù)的主要技術(shù)特點
⑴與其他軟啟動方式相比,全部實現(xiàn)了電器軟啟動控制,刮板輸送機傳動系統(tǒng)和供電系統(tǒng)得到最大的簡化;
⑵啟動時間可隨負載自行調(diào)節(jié);
⑶實現(xiàn)了刮板輸送機滿載及空載的平穩(wěn)啟動;
⑷大幅度降低了啟動電流,提高電網(wǎng)供電質(zhì)量,減少電網(wǎng)沖擊。
2.5中部槽
中部槽是整個工作面輸送機的軀干,其使用壽命是衡量整機使用壽命的重要指標。目前中部槽多采用∑形斷面槽幫、整體鑄焊封底結(jié)構(gòu),壽命已達1000萬t。為了進一步提高使用壽命,國內(nèi)外主要生產(chǎn)廠商對中部槽外形、結(jié)構(gòu)及材料等方面有進行了大量的研究。如德國某公司通過研究和開發(fā),撥那個在井下對不同斷面的中部槽進行大量試驗,最終發(fā)現(xiàn),與∑形斷面槽幫相比,弧形斷面槽幫使刮板與槽幫內(nèi)側(cè)面接觸液力小,從而減小摩擦
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