1、 （ 二 一 三 年 六 月 本科毕业设计 外文文献翻译 学生姓名 ： 学 院 ： 机械学院 系 别： 机械系 专 业： 机 械 电 子 工 程 班 级： 机电 09 指导教师 ： 讲师 学校代码： 10128 学 号： 内蒙古工业大学本科毕业设计说明书 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
2、, Crawley 6009, Australia. E-mail pieromech.uwa.edu.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 investiga
3、tions 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 conventiona
4、l 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-
5、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 m
6、odel 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 E
7、lsevier 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)
8、 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
9、 gives good control over product size. The use of spring-loaded rolls 内蒙古工业大学本科毕业设计说明书 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 l
10、ike 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 t
11、he 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
12、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
13、 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 OP
14、ERATION 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
15、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
16、 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.
