綜采工作面2500t.h可彎曲刮板輸送機設(shè)計-SGZ1000-2000重型礦用刮板輸送機含9張CAD圖
綜采工作面2500t.h可彎曲刮板輸送機設(shè)計-SGZ1000-2000重型礦用刮板輸送機含9張CAD圖,工作面,彎曲,曲折,輸送,設(shè)計,sgz1000,重型,礦用刮板,cad
外文資料
Mine scraper conveyor soft-start mode
of selection and application
High yield and high efficiency in the coal mine fully mechanized coal face of the building, to face big-long, large to support the requirements of the power of Shearer and scraper conveyor. Ordinary fully mechanized coal face of the long-general in about 150 m, scraper conveyor transport capacity of 500 t / h around high yield and high efficiency and fully mechanized coal face of the long-General to 180 ~ 300 m, scraper conveyor transport capacity of 800 t / h and above, therefore, conveyor power greater growth. Pingdingshan Coal Mining Group Company to as an example, the scraper conveyor of power in most 400 (2 × 200) kW and above, the largest for the 750 (2 × 375) kW. Scraper conveyor to the start-up launched mainly two-speed, limited by a small number of filling hydraulic coupler, which started two kinds of ways, not only operating costs, and it stands high. Therefore, the need to seek new technology and equipment to meet the requirements of high yield and high efficiency.
一、current situation and existing problems
(一) limit filling hydraulic coupler in the high-power, big load, its size, when it with the motor and reducer connection, the greater the share of space. Limited space in the work of the occasion, too much volume will scraper conveyor layout difficult. Coupled with increased hydraulic transmission distance and high-speed rotating state and easy to have a greater impact on the radial dynamic load, and the slowdown caused by electrical installations damaged. Coupled with the input and output speed than the speed of usually no more than 97 percent, that is impossible to achieve input shaft and output shaft of sync, which must exist greater power loss, reducing the efficiency of the transmission system.
(二) two-speed motor drive system is currently in China's mining scraper conveyor in common. Under normal circumstances, the rated speed motor to start the half, corresponding to start motor power is also rated power of the half. To low-speed motor launch, when the completion of the process initiated after the switch to high-speed operation, from start to the normal operation of sub-levels, in part, reduce the impact of the launch. In this way to use the special two-motor winding, two-and two-speed cable root switch. Two-speed motor complex structure, high cost, power supply system equivalent to two Motors, low-speed switching not effectively controlled, the point of failure, equipment cables, at the same time, the fault lines will be doubled the increase.
二、soft-start several advanced methods of comparison
(一) thyristor surge soft-start mode. Start the process launched at the slope, pulse conflict jump start, speed up the slope, fast slope. Pulse conflict way can jump start the biggest short-term output of over 95 per cent of the rated voltage, to impose a short-time great starting torque (equivalent to 90 per cent of direct starting torque), to overcome the static friction and the inertia of the transmission system. This soft-start approach and broad prospects for application.
(二) viscous liquid transmission soft-start mode. Dodge is a typical U.S. company CST (consecutive start transmission) soft-start devices. CST soft-start devices currently relies mainly on imports, high prices, the general mine unbearable. CST-mechanical, hydraulic, electronic control, cooling, materials for integrated, manufacturing, high-precision control, supply of spare parts in particular inconvenience. Scraper conveyor is moving equipment, changing work environment, the extremely bad conditions, equipment failure rate correspondingly increased, the greater difficulty of maintaining the higher operating costs and narrow work space constraints of the CST in China mine AFC Machine applications.
(三) Frequency soft-start mode. Scraper conveyor used, its performance advantages not play; expensive, the general mine unbearable; components used its power IGBT modules, high-voltage IGBT module of the international embargo on China, so its difficult to voltage levels To 1140 V, to its coal mine conveyor on the application has brought great difficulties.
? (四) SRM-driven approach. SRM is a new driver, in other sectors (such as the textile industry, machinery manufacturing, washing machines, etc.) have a very wide range of applications. The main feature is activated when the current low torque, speed performance, and easy to use pure electric control to achieve stepless speed regulation, and long run. Motor exclusive use of SRM, but flow, not burning motor, with good prospects for development. Components used for power IGBT module, it is very difficult to achieve voltage 1140 V. The current high-power explosion SRM is still in the development stage, the bulk smaller, higher cost, not suitable for the underground mine scraper conveyor application.
(五) soft-start mode. Taiyuan, the company developed the Whitby soft start-FM-speed technology, speed regulator technology, vacuum technology for magnetic start one, start with the characteristics of analog FM. The surge started with the way the soft start-voltage slope start, current feedback sudden jump start and start compared to the initial start more torque, can achieve the low-speed torque activated to ensure that equipment from the take-up, by Static to dynamic start running, you can solve the problem of overloading difficult start.
三、application
Pingdingshan Coal Mining Group after analysis and comparison, in October 2004 quoted a 2-QJT250/1140 (660) soft start, and Zhangjiakou Coal Factory production SGZ-764/400-scraper conveyor support, instead of the original The restrictions start filling hydraulic coupler, in a small mining 6-31080 fully mechanized coal face applications, is now running for six months, and its soft-start control of the scraper conveyor incident does not appear, better-performing.
The starter the following key features: ① and hydraulic coupler, compared with two-speed motor, scraper conveyor drive system and power supply system to maximize the simplified, the reliability of the system significantly increased. ② start the process of, 5 s power to block protection. ③ start the process of automatic measurement load, automatically determine sudden jump start, the commencement of the biggest obstacles, the largest motor torque, the buck started to overcome the shortcomings. ④ the starter all-digital control circuit, is set up to facilitate the actual starting current can be accurately controlled in the following 4 Ie, the current small motor launch, reduce the impact of the power grid. ⑤ scraper conveyor loaded with empty and a smooth start to maximize the Elimination of Transmission of the fixed-load, effectively preventing the Duanlian, breakpoints, roller key transmission components, such as damage to the accident. ⑥ VVVF soft start with a fuzzy control technology, based on load automatically determine the size of start-up time. Load large, extended start-up time, reduce the equipment dynamic impact load hours, because of the dynamic impact of the equipment smaller, the system automatically reduce the start-up time, can reduce the impact of the motor life.
Mine transportation equipment, long working hours (16 ~ 18 h / d), a large number complex system, supporting equipment, supporting links, delivery of materials by block, the impact of waste, launched frequent launch accidents. Fully-face failure in the electrical and mechanical equipment, scraper conveyor failures accounted for about 40 percent. In light of the above reasons, and because of soft-start the development of fully mechanized coal face scraper conveyor launch control for technical improvements is not only necessary but also feasible. SCR Mine scraper conveyor soft-start is the high yield and high efficiency fully mechanized coal face of the important technology and equipment, with great application value. The project's successful application to reduce the fully mechanized coal face mechanical and electrical accidents, improve yield and reduce consumption is of great significance.
中文譯文
礦用刮板輸送機軟啟動方式的選擇與應(yīng)用
在煤礦高產(chǎn)高效綜采工作面的建設(shè)中,以工作面大采長、大走向的要求配套了大功率的采煤機和刮板輸送機。普通綜采工作面的采長一般在150m左右,刮板輸送機的運輸能力500t/h左右;而高產(chǎn)高效綜采工作面的采長一般達到180~300m,刮板輸送機的運輸能力達800t/h以上,因此,輸送機功率增長較大。以平煤集團公司為例,刮板輸送機的功率大都在400(2×200)kW 以上,最大的為750(2×375)kW。刮板輸送機的啟動以雙速啟動為主,少數(shù)采用限矩型液力耦合器,這2種啟動方式,不僅運行費用高,而且停機率高。因此,需尋求新的技術(shù)和裝備來滿足高產(chǎn)高效的要求。
一、目前現(xiàn)狀及存在的問題
(一)限矩型液力耦合器在大功率、大負荷時,本身體積龐大,當它與電動機和減速機聯(lián)接后,所占空間更大。在工作空間受到限制的場合,過大的體積會使刮板輸送機的布置變得困難。液力耦合器增大了傳動距離,并且在高速狀態(tài)旋轉(zhuǎn),易產(chǎn)生較大的徑向動負荷沖擊,而造成電動機和減速裝置的損壞。耦合器的輸出轉(zhuǎn)速與輸入轉(zhuǎn)速之比通常不高于97%,即無法實現(xiàn)輸入軸和輸出軸的同步,因而必然存在較大的功率損失,降低了傳動系統(tǒng)的效率。
(二)雙速電動機驅(qū)動系統(tǒng)目前在我國礦用刮板輸送機中普遍采用。通常情況下,電動機以額定轉(zhuǎn)速的一半啟動,相應(yīng)地啟動功率也是電動機額定功率的一半。電動機以低速啟動,當完成啟動過程后再切換到高速運轉(zhuǎn),從啟動到正常運轉(zhuǎn)分兩級進行,部分地減小了啟動沖擊。這種方式要使用專門的雙繞組電動機、雙根電纜和雙速開關(guān)。雙速電動機結(jié)構(gòu)復(fù)雜,造價高,供電系統(tǒng)相當于2臺電動機,低速切換不易有效控制,故障點多,經(jīng)常出現(xiàn)啟動失敗。隨著綜采工作面的推進,要不斷地移動設(shè)備和電纜,增大了設(shè)備電纜移動的難度,同時,電纜的故障也會成倍的增加。
二、幾種先進軟啟動方式的對比
(一)晶閘管調(diào)壓軟啟動方式。啟動過程分斜坡啟動、脈沖突跳啟動、加速斜坡、快速斜坡。脈沖突跳啟動方式可以短時輸出最大達95%的額定電壓,施加一個短時的大啟動力矩(相當于90%直接啟動轉(zhuǎn)矩),以克服大的靜摩擦力和大的傳動系統(tǒng)慣性。這種軟啟動方式應(yīng)用前景廣闊。
(二)液體粘性傳動軟啟動方式。典型的是美國Dodge公司CST(連續(xù)啟動傳動)軟啟動裝置。CST軟啟動裝置目前主要依賴進口,其價格昂貴,一般礦井難以承受。CST集機械、液壓、電子控制、冷卻、材料為一體,制造、控制精度高,備件供應(yīng)特別不便。刮板輸送機是移動設(shè)備,工作環(huán)境不斷變化,條件極為惡劣,設(shè)備故障率相應(yīng)增大,較大的維護難度、較高的運行成本和狹窄的工作空間限制了CST在我國礦用刮板輸送機上的應(yīng)用。
(三)變頻軟啟動方式。應(yīng)用于刮板輸送機上,其性能優(yōu)勢得不到發(fā)揮;價格昂貴,一般礦井難以承受;其功率元件采用IGBT模塊,高電壓等級的IGBT模塊在國際上對我國禁運,所以其電壓等級很難達到1140V,給其在煤礦井下輸送機上的應(yīng)用帶來了很大的困難。
(四)開關(guān)磁阻電動機驅(qū)動方式。開關(guān)磁阻電動機是一種新的驅(qū)動方式,目前在其他行業(yè)(如紡織工業(yè)、機械制造業(yè)、洗衣機等)有著十分廣泛的應(yīng)用。主要特點是啟動時低電流大轉(zhuǎn)矩,調(diào)速性能好,容易用純電氣控制實現(xiàn)無級調(diào)速,并可長時間運行。電動機采用專用開關(guān)磁阻電動機,不過流,不易燒毀電動機,具有良好的發(fā)展前景。因功率元件采用IGBT模塊,電壓等級很難達到1140V。目前大功率防爆開關(guān)磁阻電動機尚處于研制階段,批量較小,成本較高,不適合在煤礦井下刮板輸送機上應(yīng)用。
(五)調(diào)壓調(diào)頻軟啟動方式。太原惠特公司研制的調(diào)壓調(diào)頻軟啟動器集調(diào)頻調(diào)速技術(shù)、調(diào)壓調(diào)速技術(shù)、真空磁力啟動器技術(shù)為一體,具有模擬調(diào)頻啟動的特點。該啟動方式與調(diào)壓軟啟動器的電壓斜坡啟動、電流反饋啟動及突跳啟動相比,具有更大的初始啟動轉(zhuǎn)矩,可實現(xiàn)低速大扭矩啟動,確保設(shè)備從張緊開始,由靜態(tài)啟動到動態(tài)運行,可以解決重載難啟動問題。
三、應(yīng)用情況
平煤集團經(jīng)過分析對比,于2004年10月引用了2臺QJT250/1140(660)調(diào)壓調(diào)頻軟啟動器,和張家口煤機廠生產(chǎn)的SGZ-764/400型刮板輸送機配套,代替原來的限矩型液力耦合器啟動方式,在一礦丁6-31080綜采工作面應(yīng)用,現(xiàn)已運行6個月,軟啟動器及其控制的刮板輸送機未出現(xiàn)事故,效果較好。
該啟動器主要特點如下:①與液力耦合器、雙速電動機相比,刮板輸送機傳動系統(tǒng)和供電系統(tǒng)得到最大的簡化,系統(tǒng)的可靠性顯著提高。②啟動過程中,5s堵轉(zhuǎn)斷電保護。③啟動過程中,自動測量負載,自動確定突跳啟動點,在啟動阻力最大時,電動機的扭矩最大,克服了降壓啟動的缺點。④該啟動器采用全數(shù)字控制電路,功能設(shè)定方便,實際啟動電流可以精確地控制在4A以下,電動機啟動電流小,減少了電網(wǎng)沖擊。⑤刮板輸送機滿載及空載啟動平穩(wěn),最大限度地消除對傳動部分的動沖負載,有效防止了斷鏈、斷點、滾鍵、損壞傳動元件等事故。⑥調(diào)壓調(diào)頻軟啟動器采用了模糊控制技術(shù),依據(jù)負載的大小自動確定啟動時間。負載大時,延長啟動時間,減少對設(shè)備的動載沖擊;負載小時,由于對設(shè)備的動載沖擊較小,系統(tǒng)自動縮短啟動時間,可減少對電動機壽命的影響。
礦井運輸設(shè)備工作時間長(16~18h/d),數(shù)量多,系統(tǒng)復(fù)雜,配套設(shè)備多,配套環(huán)節(jié)多,運送的物料受塊度、矸石的影響,啟動頻繁,啟動事故多。綜采工作面機電設(shè)備故障中,刮板輸送機故障占到約40%。鑒于以上原因,又由于軟啟動技術(shù)的發(fā)展,對綜采工作面刮板輸送機啟動控制進行技術(shù)改進不僅是必要的,而且是可行的。晶閘管調(diào)壓調(diào)頻礦用刮板輸送機軟啟動器是高產(chǎn)高效綜采工作面的重要技術(shù)與裝備,具有較大的推廣應(yīng)用價值。該項目的成功應(yīng)用對減小綜采工作面機電事故、提高單產(chǎn)、降低消耗具有重大意義。
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