外文翻譯--在非圓柱輥式破碎機(jī)中粉碎

（ 二 一 三 年 六 月 本科畢業(yè)設(shè)計(jì) 外文文獻(xiàn)翻譯 學(xué)生姓名 ： 學(xué) 院 ： 機(jī)械學(xué)院 系 別： 機(jī)械系 專 業(yè)： 機(jī) 械 電 子 工 程 班 級(jí)： 機(jī)電 09 指導(dǎo)教師 ： 講師 學(xué)校代碼： 10128 學(xué) 號(hào)： 內(nèi)蒙古工業(yè)大學(xué)本科畢業(yè)設(shè)計(jì)說(shuō)明書(shū) 原文： COMMINUTION IN A NON-CYLINDRICAL ROLL CRUSHER* P. VELLETRI and D.M. WEEDON Dept. of Mechanical & Materials Engineering, University of Western Australia, 35 Stirling Hwy, Crawley 6009, Australia. E-mail .au Faculty of Engineering and Physical Systems, Central Queensland University, PO Box 1319 Gladstone, Qld. 4680, Australia (Received 3 May 2001; accepted 4 September 2001) Velletri and Weedon, 2000 P. Velletri and D.M. Weedon, Preliminary investigations into a roll crusher with non-cylindrical rolls, Proc. Minprex 2000 International Congress on Mineral Processing and Extractive Metallurgy, AIMM, Melbourne (2000), pp. 321328. ABSTRACT Low reduction ratios and high wear rates are the two characteristics most commonly associated with conventional roll crushers. Because of this, roll crushers are not often considered Jor use in mineral processing circuits, and many of their advantages are being largely overlooked. This paper describes a novel roll crusher that has been developed in order to address these issues.Referred to as the NCRC (Non-Cylindrical Roll Crusher), the new crusher incorporates two rolls comprised of an alternating arrangement of plane and convex or concave surfaces. These unique roll profiles improve the angle of nip, enabling the NCRC to achieve higher reduction ratios than conventional roll crushers. Tests with a model prototype have indicated thar even for very hard ores, reduction ratios exceeding l0:l can be attained. In addition, since the comminution process in the NCRC combines the actions of roll and jaw crushers there is a possibility O that the new profiles may lead to reduced roll wear rates. 2001 Elsevier Science Ltd. All rights reserved. Keywords: Comminution; crushing INTRODUCTION Conventional roll crushers suffer from several disadvantages that have led to their lack of popularity in mineral processing applications. In particular, their low reduction ratios (typically limited to about 3:1) and high wear rates make them unattractive when compared to other types of comminution equipment, such as cone crushers. There are, however, some characteristics of roll crushers that are very desirable from a mineral processing point of view. The relatively constant operating gap in a roll crusher gives good control over product size. The use of spring-loaded rolls 內(nèi)蒙古工業(yè)大學(xué)本科畢業(yè)設(shè)計(jì)說(shuō)明書(shū) make these machines tolerant to uncrushable material (such as tramp metal). In addition, roll crushers work by drawing material into the compression region between the rolls and do not rely on gravitational feed like cone and jaw crushers. This generates a continuous crushing cycle, which yields high throughput rates and also makes the crusher capable of processing wet and sticky ore. The NCRC is a novel roll crusher that has been developed at the University of Western Australia in order to address some of the problems associated with conventional roll crushers. The new crusher incorporates two rolls comprised of an alternating arrangement of plane and convex or concave surfaces. These unique roll profiles improve the angle of nip, enabling the NCRC to achieve higher reduction ratios than conventional roll crushers. Preliminary tests with a model prototype have indicated that, even for very hard ores,reduction ratios exceeding 10:I can be attained (Vellelri and Weedon, 2000). These initial findings were obtained for single particle feed. where there is no significant interaction between particles during comminution. The current work extends the existing results by examining multi-particle comminution in the NCRC. It also looks at various other factors that influence the performance of the NCRC and explores the effectiveness of using the NCRC for the processing of mill scats. PRINCIPLE OF OPERATION The angle of nip is one of the main lectors effecting the performance of a roll crusher. Smaller nip angles are beneficial since they increase the likelihood of particles being grabbed and crushed by the rolls. For a given feed size and roll gap, the nip angle in a conventional roll crusher is limited by the size of the rolls. The NCRC attempts to overcome this limitation through the use of profiled rolls, which improve the angle of nip at various points during one cycle (or revolution) of the rolls. In addition to the nip angle, a number of other factors including variation m roll gap and mode of comminution were considered when selecting the roll profiles. The final shapes of the NCRC rolls are shown in Figure I. One of the rolls consists of an alternating arrangement of plane and convex surfaces, while the other is formed from an alternating arrangement of plane and concave surfaces. 內(nèi)蒙古工業(yè)大學(xué)本科畢業(yè)設(shè)計(jì)說(shuō)明書(shū) The shape of the rolls on the NCRC result in several unique characteristics. The most important is that, for a given particle size and roll gap, the nip angle generated m the NCRC will not remain constant as the rolls rotate. There will be times when the nip angle is much lower than it would be for the same sized cylindrical rolls and times when it will be much higher. The actual variation in nip angle over a 60 degree roll rotation is illustrated in Figure 2, which also shows the nip angle generated under similar conditions m a cylindrical roll crusher of comparable size. These nip angles were calculated for a 25ram diameter circular particle between roll of approximately 200ram diameter set at a I mm minimum gap. This example can be used to illustrate the potential advantage of using non-cylindrical rolls. In order for a particle to be gripped, the angle of nip should normally not exceed 25 . Thus, the cylindrical roll crusher would never nip this particle, since the actual nip angle remains constant at approximately 52 . The nip angle generated by the NCRC, however, the below 25 once as the rolls rotate by (0 degrees. This means that the non-cylindrical rolls have a possibility of nipping the particle 6 times during one roll revolution. EXPERIMENTAL PROCEDURE The laboratory scale prototype of the NCRC (Figure 3) consists of two roll units, each comprising a motor, gearbox and profiled roll. Both units are mounted on linear bearings, which effectively support any vertical component of force while enabling horizontal motion. One roll unit is horizontally fixed while the other is restrained via a compression spring, which allows it to resist a varying degree of horizontal load. 內(nèi)蒙古工業(yè)大學(xué)本科畢業(yè)設(shè)計(jì)說(shuō)明書(shū) The pre-load on the movable roll can be adjusted up to a maximum of 20kN. The two motors that drive the rolls are electronically synchronised through a variable speed controller, enabling the roll speed to be continuously varied up to 14 rpm (approximately 0.14 m/s surface speed). The rolls have a centre-to-centre distance ,at zero gap setting) of I88mm and a width of 100mm. Both drive shafts are instrumented with strain gauges to enable the roll torque to be measured. Additional sensors are provided to measure the horizontal force on the stationary roll and the gap between the rolls. Clear glass is fitted to the sides of the NCRC to facilitate viewing of the crushing zone during operation and also allows the crushing sequence to be recorded using a high-speed digital camera. Tests were performed on several types of rocks including granite, diorite, mineral ore, mill scats and concrete. The granite and diorite were obtained from separate commercial quarries; the former had been pre-crushed and sized, while the latter was as-blasted rock. The first of the ore samples was SAG mill feed obtained from Normandy Minings Golden Grove operations, while the mill scats were obtained from Aurora Golds Mt Muro mine site in central Kalimantan. The mill scats 內(nèi)蒙古工業(yè)大學(xué)本科畢業(yè)設(shè)計(jì)說(shuō)明書(shū) included metal particles of up to 18ram diameter from worn and broken grinding media. The concrete consisted of cylindrical samples (25mm diameter by 25ram high) that were prepared in the laboratory in accordance with the relevant Australian Standards. Unconfined uniaxial compression tests were performed on core samples (25mm diameter by 25mm high) taken from a number of the ores. The results indicated strength ranging from 60 MPa for the prepared concrete up to 260 MPa for the Golden Grove ore samples. All of the samples were initially passed through a 37.5mm sieve to remove any oversized particles. The undersized ore was then sampled and sieved to determine the feed size distribution. For each trial approximately 2500g of sample was crushed in the NCRC. This sample size was chosen on the basis of statistical tests, which indicated that at least 2000g of sample needed to be crushed in order to estimate the product P80 to within +0.1ram with 95% confidence. The product was collected and riffled into ten subsamples, and a standard wet/dry sieving method was then used to determine the product size distribution. For each trial, two of the sub-samples were initially sieved. Additional sub-samples were sieved if there were any significant differences in the resulting product size distributions. A number of comminution tests were conducted using the NCRC to determine the effects of various parameters including roll gap, roll force, feed size, and the effect of single and multi-particle feed. The roll speed was set at maximum and was not varied between trials as previous experiments had concluded that there was little effect of roll speed on product size distribution. It should be noted that the roll gap settings quoted refer to the minimum roll gap. Due to the non-cylindrical shape of the rolls, the actual roll gap will vary up to 1.7 mm above the minimum setting (ie: a roll gap selling of l mm actually means 1-2.7mm roll gap). 內(nèi)蒙古工業(yè)大學(xué)本科畢業(yè)設(shè)計(jì)說(shuō)明書(shū) 譯文： 在非圓柱輥式破碎機(jī) 中 粉碎 P. VELLETRI and D.M. WEEDON 機(jī)械與材料工程，西澳大利亞大學(xué)，斯特林 HWV35 部， 克勞利 6009，澳大利亞。電子郵箱 .au 工程學(xué)院和物理系統(tǒng)，中央昆士蘭大學(xué)，郵政信箱 1319 格萊斯頓， QLD。 4680，澳大利亞 （ 2001 年 5 月 3 日收稿， 2001 年 9 月 4 日接受） 韋萊特里和威登， 2000 年 P.韋萊特里和 D.M.威登，與非圓柱輥， PROC 的輥式破碎機(jī)進(jìn)行初步調(diào)查。 Minprex2000 選礦和冶煉， AIMM，墨爾本國(guó)際大會(huì)（ 2000年），頁(yè) 321-328。 摘 要 低的破碎比和高的磨損率是與傳統(tǒng)的破碎機(jī)相聯(lián)系的很常見(jiàn)的兩個(gè)特性。因?yàn)檫@點(diǎn)，在礦石處理流程的應(yīng)用中，很少考慮到它們，并且忽略了很多它們的優(yōu)點(diǎn)。本文描述了一個(gè)已被發(fā)展起來(lái)的新穎的對(duì)輥破碎機(jī)，旨在提出這些論點(diǎn)。作為 NCRC,這種新式破碎機(jī)結(jié)合了兩個(gè)輥筒，它們由一個(gè)交替布置的平面和一個(gè)凸的或者凹的表面組成。這種獨(dú)特的輥筒外形提高了嚙合角，使 NCRC 可以達(dá)到比傳統(tǒng)輥式破碎機(jī)更高的破碎比。用一個(gè)模型樣機(jī)做的試驗(yàn)表明：即使對(duì)于非常硬的礦石，破碎比任可以超過(guò) 10。另外，既然在 NCRC 的破碎處理中結(jié)合了輥式和顎式破碎機(jī)的作用 ，那就有一種可能：那種新的輪廓會(huì)帶來(lái)輥?zhàn)幽p率的降低。 關(guān)鍵字： 粉碎；破碎 介 紹 傳統(tǒng)的輥筒破碎機(jī)因?yàn)榫哂袔讉€(gè)缺陷而導(dǎo)致了其在礦石處理應(yīng)用中的不受內(nèi)蒙古工業(yè)大學(xué)本科畢業(yè)設(shè)計(jì)說(shuō)明書(shū) 歡迎。尤其是當(dāng)與其它的一些破碎機(jī)比起來(lái)，諸如圓錐破碎機(jī)等，它們的低破碎比（一般局限在 3 以內(nèi)）和高的磨損率使它們沒(méi)有吸引力。然而，從礦石處理這一點(diǎn)來(lái)說(shuō)，輥筒破碎機(jī)有一些非?？扇〉奶攸c(diǎn)：輥筒破碎機(jī)的相對(duì)穩(wěn)定的操作寬度可以很好控制產(chǎn)物粒度。彈簧承重的輥?zhàn)拥氖褂檬惯@些機(jī)器容許不可破碎的物料（諸如夾雜金屬等）。另外，輥筒破碎機(jī)是這樣工作的：將物料牽引至輥?zhàn)又g 的擠壓區(qū)而不是象圓錐和顎式破碎機(jī)那樣依靠重力。這產(chǎn)生了一個(gè)連續(xù)的破碎周期，避免了高通過(guò)率，同時(shí)也使破碎機(jī)可處理潮濕的和膠粘的物料。 NCRC 是一種新穎的破碎機(jī)，發(fā)明于澳大利亞西部大學(xué)，為得是提出一些與傳統(tǒng)輥筒破碎機(jī)相聯(lián)系的一些問(wèn)題。新的破碎機(jī)結(jié)合了兩個(gè)輥?zhàn)樱砷g隔布置的平面和凸的或者凹的表面組成。這種獨(dú)特的輥?zhàn)虞喞岣吡藝Ш辖牵?NCRC 可達(dá)到比傳統(tǒng)輥筒破碎機(jī)更高的破碎比。用一個(gè)模型樣機(jī)的初步試驗(yàn)已表明：即使非常硬的物料，超過(guò) 10 的破碎比也可以實(shí)現(xiàn)。這些初期的發(fā)現(xiàn)是通過(guò)單一顆粒進(jìn)給而獲得的，在破碎中沒(méi)有顯 著的物塊間的相互作用。目前的工作在 NCRC 中用多物塊試驗(yàn)延伸了現(xiàn)存的結(jié)果。同時(shí)也顧及了各種其他因素：影響 NCRC 特性和探索 NCRC 在選礦處理中使用效率。 操作原理 嚙合角是影響輥筒破碎機(jī)性能的重要因素之一。小的嚙合角是有利的，因?yàn)樗鼈冊(cè)龃罅宋飰K被輥筒抓住的可能性。對(duì)于一個(gè)給定的入料粒度和輥隙，傳統(tǒng)的輥筒破碎機(jī)的嚙合角受限于輥筒的尺寸。 NCRC 試圖通過(guò)有特殊輪廓的輥筒克服這種限制，這種輪廓提高了輥筒在一轉(zhuǎn)中變化點(diǎn)的嚙合角。至于嚙合角，在選擇輥面時(shí)，很多其他的因素，包括變化的輥隙，破碎的方式都考慮了。最終 NCRC輥筒形狀如圖 1 所示。其中一個(gè)輥?zhàn)佑砷g隔布置的平面和凸面組成，而另一個(gè)是由間隔布置的平面和凹面組成。 NCRC 輥筒的形狀導(dǎo)致了幾個(gè)獨(dú)特的特點(diǎn)。其中最重要的就是在輥筒轉(zhuǎn)動(dòng)時(shí)，對(duì)于一個(gè)給定物塊粒度和輥隙， NCRC 所產(chǎn)生的嚙合角將不再保持穩(wěn)定。時(shí)而嚙合角比相同尺寸的圓柱輥筒低很多，時(shí)而高很多。輥?zhàn)愚D(zhuǎn)動(dòng)中嚙合角的實(shí)際變化量超過(guò) 60 度，如圖 2 所示，圖 2 也表示了相同情況下，可相比尺寸的圓柱輥筒破碎機(jī)所產(chǎn)生的嚙合角。這些嚙合角是對(duì)一個(gè)直徑為 25 毫米的圓形物塊放在輥徑大約 200 毫米、最小輥隙 1 毫米的輥筒間計(jì)算出來(lái)的。這 個(gè)例子可以用來(lái)描述內(nèi)蒙古