scholarly journals DETERMINATION OF THE CHANGE OF THE DESIGN POSITION OF THE PROFILE OF THE BELT CONVEYOR ON THE LOAD OF THE ROLLER BEARINGS

2020 ◽  
pp. 20-25
Author(s):  
Oleksandr Danilin ◽  
Stefan Zaichenko ◽  
Stepan Shevchuk ◽  
Natalia Jukova ◽  
Ivan Pasichniuk

The article attempts to establish the basic patterns in the formation of loads in the structure of the conveyor frame due to changes in the design position of the constituent elements based on analytical calculations. The amortization replacement of rollers and the establishment of a change in the projected resource caused the change in the design position.The aim of the work is to study the interaction of the elements of the belt conveyor on the convex region of the profile when the design position changes and to determine the change in the resource of the roller support elements. The purpose of the work is formulated from the analysis of unplanned stops and premature replacement of conveyor elements, in particular conveyor rollers, on the convex region of the profile.To achieve this goal the influence of the geometric parameters of the convex section of the belt conveyor profile on the force interaction of the belt and roller supports was considered, and the change in the resource of the roller bearings was determined.To characterize the geometric parameters of the convex section of the belt conveyor, the following were selected: the number of roller supports, the distance between the roller supports, the radius of curvature of the conveyor profile, the angle of the curved section. The mathematical model is based on the belt equilibrium equation, which contains the tension forces of the conveyor belt and the forces from the action of roller supports. Particular attention is paid to establishing the effect of changing the geometric parameters of the convex section on the roller bearing life. It has been established that a decrease in the radius of the transitional convex section as a result of a change in the initial design position by 2.4 times leads to an increase in the force acting on the roller support by 161%. It was found that the increase in force is the reason for the rapid exit from the operational state of the rolling bearings of the roller bearings, as evidenced by the intensive drop in the resource of the rollers (18 times).The proposed algorithm for determining the main parameters of the force interaction of the elements of the belt conveyor on the convex region of the profile will make it possible to predict the resource and prevent the conveyor from leaving the premature operational state.

2019 ◽  
Vol 109 ◽  
pp. 00096
Author(s):  
Andrii Smirnov ◽  
Tamara Mishchenko

The article presents methods for determining loads on rollers of a six-roll support of a tubular belt conveyor, based on the equilibrium laws of elastic cylindrical plates and shells filled with a freight. In this case, the forces acting on the rollers of the tubular conveyor are the sum of the forces caused by the weight and expansion of the bulk load, the weight and bend of the belt, as well as the inertial forces associated with the curvature and the deflection of the belt under the weight of the bulk load. The dynamic forces acting on the rollers as the belt moves are determined from the equation of the oscillations of a heavy flexible string using the Ritz method. As a result of the research, analytical dependences of the forces acting on the rollers of the six-roller support of the tubular conveyor on the parameters of the conveyor, the belt, the properties of the bulk load and the radius of curvature of the conveyor are obtained, and an assessment of the component these forces is given. The results can be used to determine the parameters of the tubular conveyors rollers and increase the service life of the rollers.


2021 ◽  
Vol 2094 (4) ◽  
pp. 042071
Author(s):  
I M Klebanov ◽  
V V Murashkin ◽  
M I Kondratev ◽  
I E Adeyanov ◽  
K A Polyakov

Abstract The paper investigates the influence of the process of running-in the ends of rollers and sides of cylindrical roller bearings on the conditions of hydrodynamic contact of these parts: the formation of an oil film and friction. For this purpose, the results of finite element modeling of the stress-strain state of the bearing parts in contact: the inner ring, the side flange and a fragment of the axle of the wheelset, and the multi-mass simulation of the dynamics of the bearing operation are used. The influence of the yaw angle of the roller on the size and shape of the contact area on the side is investigated. The dependences for calculating the thickness of the oil film in the contact between the ends of the rollers and the flanges of the bearing rings are being refined, which now make it possible to take into account the misaligned position of these parts during their force interaction. The results are illustrated using the example of a roller bearing of standard size 232926.


2013 ◽  
Vol 437 ◽  
pp. 682-685 ◽  
Author(s):  
Gang Cheng ◽  
Yong Cun Guo ◽  
Kun Hu ◽  
Peng Yu Wang

Magnetic suspension type belt conveyor used magnetic machinery technology design can solve the belt conveyor of roller support parts number, large energy consumption and high maintenance cost, limited tape speed, large noise and other issues. Magnetic belt conveyor design is the key to stability analysis of the operation of conveyor belt. Papers from a mechanical point of view to study the structural stability calculation. The results show that small interfering in the external magnetic conveyor belt, the permanent support system can be adjusted to spontaneously stable equilibrium state.


2021 ◽  
Vol 303 ◽  
pp. 01044
Author(s):  
Alexander Zakharov ◽  
Natalya Erofeeva

The dynamics of interaction of the large lumps of the bulk cargo with a conveyor belt while passing through roller supports of the conveyor linear sections is often a cause of damage on the conveyor belt. In order to reduce the negative impact it is proposed to isolate the conveyor belt surface from the large lumps by filling small fractions of the bulk cargo by means of adding a shock device to the conveyor structure that causes increased segregation of the bulk cargo. A mathematical model of the segregation of the bulk cargo located on the conveyor belt and in zone of impact of the shock pulses has been developed. The model considers a change in the rotation direction of the large lump when applying shock pulses to the characteristic points of the lump lower face. Herewith it takes into consideration weakening of the shock pulse by a layer of the bulk cargo small fractions. The presented model has received experimental confirmation. Analytically and experimentally the height of filling of the bulk cargo small fractions under a large lump when passing the vibrating impact device located on the conveyor belt has been determined.


2021 ◽  
Vol 303 ◽  
pp. 01027
Author(s):  
Vadim Yurchenko ◽  
Valeriy Nesterov

The planned increase in the mine output from 6.5 to 13.6 million tons per year has set the task of reconstructing a conveyor transport in the eastern inclined shaft of the Raspadskaya mine. The roadway length is 4100 m; the reduced inclination angle is +7°40´. An attempt was made to combine all the positive global practices in one project: the distribution of drive power along the length of a conveyor belt, minimizing the capital cost of implementation. Within the framework of this article, an approach to choosing the speed of a con-veyor belt is discussed, a comparative analysis of the two most com-mon types of intermediate “tripper-type” and “belt-to-belt” drives is given; calculation of a belt conveyor with intermediate “belt-to-belt” drives providing non-reloading conveying in the eastern inclined shaft. Pull force calculations showed that a conveyor belt with four interme-diate “belt-to-belt” drives can be implemented as follows: belt width – 1400 mm, belt speed – 4.0 m/s, mono-material load-carrying belt – PVG-4000, mono-material drive belt – PVG-1400, 2-pulley drive units when mounted on one side: head drive power – 2×1000 = 2000 kW, intermediate drive power – 2×1600 = 3200 kW. Thus, the use of a conveyor belt with four intermediate “belt-to-belt” drives in the in-clined shaft will give the following results: non-reloading transporta-tion over the entire length of the shaft, reducing the additional degra-dation of transported coal due to the exclusion of reloading points, minimizing costs through the use of less durable belts, minimizing costs of sinking an inclined shaft of a smaller cross-section.


2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Wei-Li Qin ◽  
Wen-Jin Zhang ◽  
Zhen-Ya Wang

Roller bearings are one of the most commonly used components in rotational machines. The fault diagnosis of roller bearings thus plays an important role in ensuring the safe functioning of the mechanical systems. However, in most cases of bearing fault diagnosis, there are limited number of labeled data to achieve a proper fault diagnosis. Therefore, exploiting unlabeled data plus few labeled data, this paper proposed a roller bearing fault diagnosis method based on tritraining to improve roller bearing diagnosis performance. To overcome the noise brought by wrong labeling into the classifiers training process, the cut edge weight confidence is introduced into the diagnosis framework. Besides a small trick called suspect principle is adopted to avoid overfitting problem. The proposed method is validated in two independent roller bearing fault experiment vibrational signals that both include three types of faults: inner-ring fault, outer-ring fault, and rolling element fault. The results demonstrate the desirable diagnostic performance improvement by the proposed method in the extreme situation where there is only limited number of labeled data.


Author(s):  
Tobias Hultqvist ◽  
Aleks Vrček ◽  
Tomas Johannesson ◽  
Pär Marklund ◽  
Roland Larsson

The use of roller bearings as crankshaft main bearings has shown potential in reducing the fuel consumption of internal combustion engines. An effective way to mount the roller bearing onto the crankshaft is to split the outer ring. However, this may lead to a severe out-of-roundness in the split region when the bearing is mounted, further implying increased noise, vibrations and contact stresses. In this work, a novel approach to study the plasto-elastohydrodynamic contact using commercial finite element software is developed. The modelling approach is based on the contact moving in space, allowing for the stress history based on the lubricant pressure to be studied in a straight-forward manner. The model is first utilised to study the influence of asperities on the lubricating conditions, indicating that stresses may exceed the yield strength of the material due to the transient effects taking place when the surface feature is over-rolled. Thereafter, the model is used to analyse the step in a mounted crankshaft roller bearing with the purpose of specifying a critical step height, which implies zero plasticity and thereby a reduced risk of accumulated damage in the vicinity of the step.


2019 ◽  
Vol 2019 ◽  
pp. 1-17 ◽  
Author(s):  
Yanfeng Peng ◽  
Junhang Chen ◽  
Yanfei Liu ◽  
Junsheng Cheng ◽  
Yu Yang ◽  
...  

Adaptive sparsest narrow-band decomposition (ASNBD) method is proposed based on matching pursuit (MP) and empirical mode decomposition (EMD). ASNBD obtains the local narrow-band (LNB) components during the optimization process. Firstly, an optimal filter is designed. The parameter vector in the filter is obtained during optimization. The optimized objective function is a regulated singular local linear operator so that each obtained component is limited to be a LNB signal. Afterward, a component is generated by filtering the original signal with the optimized filter. Compared with MP, ASNBD is superior in both the physical meaning and the adaptivity. Drawbacks in EMD such as end effect and mode mixing are reduced in the proposed method because the application of interpolation function is not required. To achieve the fault diagnosis of roller bearings, raw signals are decomposed by ASNBD at first. Then, appropriate features of the decomposed results are chosen by applying distance evaluation technique (DET). Afterward, different faults are recognized by utilizing maximum margin classification based on flexible convex hulls (MMC-FCH). Comparisons between EMD and ASNBD show that the proposed method performs better in the antinoise performance, accuracy, orthogonality, and extracting the fault features of roller bearings.


2020 ◽  
Vol 10 (13) ◽  
pp. 4436
Author(s):  
Fei Zeng ◽  
Cheng Yan ◽  
Qing Wu ◽  
Tao Wang

For the conveyor belt, variable material flow influences the energy efficiency of the speed control technology significantly. The fluctuation of material flow on the conveyor belt will lead to the detrimental vibrations on both the belt and the conveyor while the conveyor works at certain speeds. In order to improve the model inaccuracy caused by the uniform bulk material flow assumption in the current conveyor belt model, the paper establishes a high-precision dynamic model that can consider speed control of a conveyor belt under non-uniform bulk material transportation. In this dynamic model, a non-uniform bulk material distribution model is firstly proposed based on laser scanning technology. Then, a high-precision longitudinal dynamic model is proposed to investigate the dynamic behavior of a belt conveyor. Considering the micro-units of actual load on a conveyor belt, it can well describe the transient state of the conveyor belt. These models can be used to determine the optimal speed for safety and energy conservation in operation. Experimental results are used to validate the proposed dynamic model for analyzing belt mechanical behavior under non-uniform bulk material distribution on the belt. The results show that the proposed models can be used for optimizing the operating procedures of belt conveyor systems.


Author(s):  
A. J. Wilkinson

It is often necessary to convey and elevate objects of widely varying characteristics in a confined space with random load conditions. The twin-band rising conveyor is essentially a steeply inclined belt conveyor which carries and controls articles on inclines of up to 60°. In order to control satisfactorily articles handled on such a conveyor, a continuous and weighted cover band, which is driven in synchronism with the conveyor belt, is employed. A horizontal toe band, which may be manually or automatically loaded, is used to aid efficient introduction to the articles between the carrying and weighted belts.


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