On-line conveyor belts inspection based on machine vision
基于机器视觉的在线输送带检测
Optik - International Journal for Light and Electron Optics, Volume 125, Issue 19, October 2014, Pages 5803-5807
Abstract: Under the background that mining conveyor belts are prone to failure in operation, the on-line fault detection technique based on machine vision for conveyor belts is investigated. High-brightness linear light sources arranged to a vaulted shape provide light for a line-array CCD camera to capture high-quality belt images. A fast image segmentation algorithm is proposed to deal belt images on-line. The algorithm for detecting longitudinal rip and belt deviation which are serious threat to the mine safety production from binary belt images is presented. Then, an on-line visual belt inspection system is developed. The laboratory testing results testify the validity of the visual inspection system.
Fault Detection with Vibration Transducers
振动传感器在故障检测中的应用
Procedia Technology, Volume 12, 2014, Pages 119–124
Abstract: Mechanical faults, usages, slackness's, cause different noises and vibrations with different amplitude and frequency against the normal sound and movement of the equipment.
The vibration transducers, accelerometers and microphone are used for noise and/or sound and vibration detection with fault detection purpose. Vibration transducers and accelerometers have three functioning domain, if the input frequency is les then the resonant frequency of the sensor it is working as an accelerometer, if the input frequency is higher then the resonant frequency of the sensor it is working as vibrometer. Detecting and analyzing the signal of the transducer, amplitude and spectral analyzing, we can detect usages, slackness and forces which act and produce the fault. Analyzing the output signal of the sensor and compare with a base signal or with nominal values mechanical faults can be detect in functioning time without stopping and to take to pieces the equipment. It is an undestroyed method to find out the functioning problems.
In this paper are presented simple transfer functions for two cases, if the mechanical system is vibrating and if through the base is transmitted a vibration to the system. The system behavior is analyzed in Matlab surround the natural frequency of the system. The amplitude and phase modification can be used for signal analysis and fault detection.
Condition monitoring of Self aligning carrying idler (SAI) in belt-conveyor system using statistical features and decision tree algorithm
统计特征及决策树算法在带式输送机系统自对准空载状况监控中的应用
Measurement, Volume 58, December 2014, Pages 274-279
Abstract: Self aligning carrying idler (SAI) is a key component of belt-conveyor has two main functions: power transmission, controlling the belt sway and change the direction of conveyor belt. As the SAI is found to be critical in heavy duty conveyor systems, it becomes an essential activity to monitor its smooth functioning. To ensure this, condition monitoring of SAI needs to be carried out which basically forms a classification problem. Self aligning carrying idler consists of the following components such as bearing, shaft, labyrinth seal and outer roller. The SAI was analyzed with the following cases such as SAI running at good condition (Good), SAI with bearing fault (BF), SAI with shaft fault (SF), SAI with labyrinth fault (LF) and SAI with outer roller fault (RF). From the experimental setup, the vibration signals were acquired for different conditions of SAI. Some useful features were extracted using statistical measures. The features were classified by decision tree algorithms. The classification results are presented in the conclusion part. The effort is to apply the statistical features and decision tree classifier to SAI and examine whether would it be made online.
Analysis of asymmetrical effect of tension forces in conveyor belt on the idler roll contact forces in the idler housing
输送带张力对托辊接触力不对称影响分析
Measurement, Volume 52, June 2014, Pages 22-32
Abstract: This paper analyses an impact of asymmetrical tension forces, which are occurring in the conveyor belt, on the contact forces in the guiding idlers. It describes causes of an increased wear-out of the conveyor belts due to an asymmetric tensioning of the transport belt. There were investigated five measuring points loaded with a symmetrical and asymmetrical tensioning of a specimen section of the pipe conveyor transport belt, using the Friedman test for the factor of asymmetry. The tension force determines also changes of the contact force layouts in the individually investigated idler rolls. A newly developed method was applied in order to identify states of the particular experimental phases for the process of the transport belt tensioning and relaxation. This method is based on differences of the contact force time behaviours. It is possible to present a hypothesis, taking into consideration the obtained results that a side slipping of the running conveyor belt is caused by the tension force asymmetry also on the real operational conditions.
Using logistic regression in tracing the significance of rubber–textile conveyor belt damage
逻辑回归在橡胶织物输送带破坏程度监测中的应用
Wear, Volume 318, Issues 1–2, 15 October 2014, Pages 145-152
Abstract: The main purpose of this work is to investigate different levels of damage that occur on rubber–textile conveyor belts. The conveyor belt damage depends on the heterogeneity of the transported material, transporting conditions and on attributes of the conveyor belt itself. The conveyor belts that are used in this study were divided into three categories: new, worn and renovated. In total, 67 test specimens were examined. The logistic regression method was selected in order to analyze individual levels of conveyor belt damage. Using this method, two differently shaped impact drop hammer tips (spherical and pyramidal) were applied and analyzed. Impact height of the drop hammer and the type of conveyor belt were treated as the independent variables. The output variable was selected as the one that best differentiated between significant and insignificant belt damage. The result of the work enables to estimate the odds of formation of the significant conveyor belt damage for the individual variables. A surprising result, which is obtained from the performed tests and model analyses, is a fact that application of a new, unused conveyor belt, leads actually to increased odds of the belt׳s significant damage.
Failure analysis of irreversible changes in the construction of rubber–textile conveyor belt damaged by sharp-edge material impact
尖角材料撞击引起的橡胶织物输送带不可逆结构变化故障分析
Engineering Failure Analysis, Volume 39, April 2014, Pages 135-148
Abstract: One of the most frequently damage of rubber–textile conveyor belt is caused by sharp-edge material impact. The paper deals with study of process of irreversible changes formation in the internal structure of rubber–textile conveyor belt caused by sharp-edge material impact. The aim of the paper is knowledge of damage process which is required for the correct regulation of operation conditions for conveyor belt. The aim is to determine conditions caused this type of damage (height of impact and weight of material impact). Non-destructive methods (computer metrotomography) is used for study of changes in the construction of conveyor belt. The paper presents theoretical and experimental evaluation of the process of conveyor belt damage.
Analysis of influence of conveyor belt overhang and cranking on pipe conveyor operational characteristics
输送带overhang and cranking对圆管输送机运行特性影响分析
Measurement, Volume 63, March 2015, Pages 168-175
Abstract: Conveyor belt, which is installed in a pipe conveyor, is subjected to various processes during its current operation, whereas these processes are causing a wear-out of the conveyor belt. The wearing process of the conveyor belt is induced predominately by influence of the transported material as well as due to improper operational conditions that are often caused as a result of an incorrect design of the idler housings. One of the possible consequences of the idler housing incorrect design is an irregular guiding of the pipe shaped belt. The incorrect guiding of the pipe shaped belt is manifested usually by an overhang and cranking of the conveyor belt. There are presented in this paper the experimentally obtained results based on a simulation of the cranking and overhang of the conveyor belt. The negative phenomena of the conveyor belt cranking and overhang were induced by means of an intentionally incorrect setting-up of the idler roller positions, in order to analyse their influence on the operational characteristics of the pipe conveyor. The experimentally investigated influence was verified by means of the developed regression models specified for description of a dependence among the normal contact forces and the tension force, as well as by the regression models, which are describing interrelations among the normal contact forces in two neighbouring idler rollers.
