Classification and Comparative Analysis of Belt Weigher Hoists

<p class="1Body">There is considered the design of kinematic configurations of belt weigher hoists from the position of mobility mechanisms. There is given an idea of groups of belt weigher errors. There are proposed the signs of classification of hoists and presented classification of these devices on the basis of which there is made the comparative analysis of their kinematic configurations. There are given recommendations on selecting rational designs of belt weigher hoists from the point of view of ensuring accuracy of weighing and realization of methods of their calibration.</p>

Development of Calibration Device for the Belt Weigher Based on the Material Superimposed Technology

Great accuracy is required in the settlement process of coal trade. In order to improve the accuracy of coal measurement, a set of online belt weigher calibration device based on the method of material superimposed has been developed. The mechanical structure of the whole device is well designed realizing material circulation conveying. At the same time the software and hardware of calibration system are fully designed.Finally the experimental results indicate that the uncertainty of the calibration device for belt weigher is within 2% and the minimum theoretical ratio of belt material superimposed is about 42% which attains the error requirement of grade 0.5.

Static Analysis on the Measurement System of an Electronic Belt Scale

The Principal Purpose of the Present Work is to Investigate the Measurement System of a Direct Loading Electronic Belt Scale with a Single Supporting Roller, Revealing the Relationship between Weight Sensor Output and Vertical as well as Horizontal Force Subjected to Carrier Roller by Means of a Finite Element Software ANSYS. the Results Conclusively Indicate that there is a Good Linear Relationship between the Vertical Force and the Sensor Output while the Output is Independent from the Horizontal One with the Full-Bridge Circuit Applied to Measuring Circuit for Transducer. Variation in Horizontal Force Acting on Carrier Roller is Not a Major Source of Error in the Measurement by a Belt Weigher.

Errors in Conveyor Belt Weigher Systems

The necessity for continuous belt weighers is first discussed. It is pointed out that they have limitations in performance which at present prevent their widest adoption and which thus make their further study important. It is shown that conveyor belt weigher systems consist of four essential elements. These elements are each considered in turn and it is concluded that the most serious errors arise in the weigh-length element, with the means by which travel of the belt is measured as a possible further source of serious error. The weigh-length element is considered in further detail and the importance of multiple weighing idlers, long idler pitch, and low belt tension, amongst other things, is emphasised. The introduction of belt sag, instead of belt tension, as a term in equations for misalignment and tension errors is shown to give a convenient result. The effect of belt stiffness on the misalignment and tension errors is examined closely. Previous formulae for this are critically examined and the author presents the results of his own efforts to find a better formula. The difficulties of applying any of these formulae in practical cases is discussed. It is explained that simple beam theory is not applicable to a troughed belt, which, it is argued, should be found much more flexible than the beam theory predicts. Finally, the conclusion is reached that if belt sag, rather than belt tension, is taken as a criterion by which a belt weigher is adjusted, then a stiff belt should give rise to smaller misalignment and tension errors than a perfectly flexible one.