外文翻译--钢绞线带式输送机的发展(编辑修改稿)

外文翻译--钢绞线带式输送机的发展(编辑修改稿)内容摘要：

It has been possible using Cable Belt belting with specially formed surfaces to run on slope conveyor systems where the overall grade is 21176。 and with particular sections of 28176。 , without experiencing slipping of the belt on the drive cables. Whilst the Cable Belt conveyor was developed at a time when the powers available of up to 300 kW were regarded as outstanding the basic concept is still retained even when now, single conveyors of 30000 metre length and 8000 kW power are being built. The terminal units are similar to those in a conventional troughed conveyor except that they also serve to separate and rejoin the carrying belt and drive cables. A typical example of a head discharge unit is shown in fig. 6. Obviously the terminals other than the drive unit are more plex than in a conventional troughed conveyor and take up more space particularly in the case of the tensioning arrangements. This is not true of the drive as for a parable power rating it is pact and has the advantage that it can be located remote from the Cable Belt conveyor belt line. Head Discharge Unit Fig 6 As the modulus of elasticity of the drive cables is kept relatively low in order to allow the use of very low starting torques and each drive cable is tensioned, the tension system does require substantial takeup space and is more plex as is illustrated in fig. 7. Typical Tensioning Arrangement Fig 7 The concepts behind the design of the Cable Belt conveyor are very similar to a conventional conveyor in that there is conveyor friction and the vertical alignment is a series of catenaries but of course the factors used vary considerably because of the different characteristics. The conveyor friction losses are considerably reduced principally because of the significantly lower number and weight of moving parts in a parable system. This reduction is normally in the order of 30%. In addition the friction losses due to the working of belt and material as they pass over the idlers are significantly less. it has been determined empirically that there is in the order of a 10% reduction in the friction losses. The establishing of the facts, even on a parative basis, with regard to conveyor friction has proved difficult as all the data is empirical and the various design standards can show markedly different results. In addition conveyor friction will vary with temperature, age and standards of installation and maintenance. However in a recent major installation it has been possible to pare the friction values, at least on a design basis and as can be seen below these bear out the differences. Conventional Cable Belt Number of Rotating Parts 100 76 Weight of Moving Parts 100 64 Friction Losses 100 67 In determining the vertical alignment of the Cable Belt system whilst the formulae and calculation are the same, great care must be exercised as it is not possible to allow 39。 lift off39。 in catenaries to occur. Early Cable Belt Belting Fig 2 Intermediate Cable Belt Belting Fig 3 Modern Cable Belt Belting Fig 4 The Cable Belt is best defined as a belt conveyor with a laterally rigid but longitudinally flexible carrying belt which is supported at or near its edges on two parallel endless looms of drive cable, these cables in turn being supported at intervals by grooved pul1eys. The integral reduction gear and drive unit drives both drive cab1es and incorporates a differential to equalise tensions in the cables. In addition each of the drive cable circuits is separately tensioned to allow for the differential stretch of these during operation. The unique feature of the Cable Belt system is the belt. Originally this was a fabric reinforced rubber belt which had moulded into it spring steel straps at 450 mm intervals. These straps protruded beyond the edges of the bell as illustrated in fig. 2, and had mechanically attached to them a metal shoe with rubber Lining where it gripped the drive cable. This was superseded by a one piece moulded construction shown in fig. 3 where smaller cross section straps at intervals of 100 mm were moulded entirely within the belt and the shoes to grip the drive cables were continuous mouldings along the edge of the belt. Typical 4 Pulley Line Stand Fig 5 Recently a further change was made, illustrated in fig. 4 whereby the shoes which grip the drive cable on the material carrying run have been moved inwards. This increases the stability of the belt when subjected to overloading and in addition allows the use of smaller cross section straps. Angle Station Fig 8 It is normal that on a typical long centre conveyor the eventual replacement of the。