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1. THE GENERAL DATA ON THE THEME
1.1 Urgency
Domestic and foreign scientists who which were engaged in the given question: prof., d. t. s. Shahmejster L.G., prof., d. t. s. Dmitriev V.G., prof., d. t. s. Spivakovskij A.O., c. t. s. Shpakunov I.A., Poshivajlo V.J., Kohler Â., Quaas H., Lauhoff H. [1-10]. In their works separate making resistance to movement have been resulted. However the question of influence of resistance components to movement and their parameters on total force of resistance to movement is investigated insufficiently, that does not enable to solve necessary industrial and practical problems. On the basis of above-stated it is possible to make the conclusion, that the further research in this direction is actual.
1.2 Scientific novelty and practical value
One of essential lacks of researches for many years is to define resistance to movement of a conveyor tape with the help of the general) factor of resistance to movement which gets out depending on conditions of operation and an operating mode of the conveyor [8, 9]. It does not take into account influence of such parameters as a preliminary tension of the tape and others. Studying of this question will allow to choose a mode with required speed of movement of the tape and the tension.
2. FINAL PART
1.2 The review of available and planned results
Let's consider the allocated making resistance to movement of the conveyor tape.
Force of resistance from deformation of the cargo and the tape. We shall consider force of resistance from deformation of the cargo and the tape [1]. The following dependence for definition is offered:
(1)
where – running weight of the cargo, N/m; – running weight of the tape, N/m ; – distance between rollers, m; – an initial tension, S
Force of resistance from cave-in of rollers in a tape [2].
(2)
where – temperature factor; – the corner of an inclination roller, a grades; – the factor accepted for the loaded tape 0,32 and for empty 0,17; – factor of Puasson, for rubber 0,475; – the module of elasticity of the bottom facing, about equal 5 – 5,5, MPa; – radius of the roller, mm; – width of the tape, mm; – the constant accepted equal 1,5; – temperature in the roller, a grades C.
In work [3] researches by definition of force of resistance to rotation of rollers are published:
(3)
where – the difference between internal and external temperature, a grades C ; – speed of rotation of the roller, m/s; – axial loadings, N; , – radial loading accordingly on average and lateral rollers, N; , – factors of axial and radial loadings; , – some constructive constants; – temperature in the roller, grades C; – the ambient temperature, a grades C.
With the help (1), (2), (3) increment of the tension on i-th roller to be defined:
(4)
For definition of total resistance to movement of the conveyor tape on one of branches of the conveyor of it in mathematical appendix MathCAD the program block which looks as following is created:
(5)
where - number of roller branches of the conveyor.
2.2 Conclusions and directions of the further researches.
On the basis of the resulted components of resistance movement of the conveyor tape can calculate an increment of the tension on adjacent roller and total force of resistance of the branch for the conveyor with width of the tape 800 mm.
In the future definition of the increment of the tension and force of resistance of the branch of the conveyor for wider range of parameters, and also an establishment influence of parameters and factors of components of resistance to movement on strength properties of the tape and power consumption of transportation is planned. The direction of the further researches is studying change of distribution of separate components in the increment of the tension depending on speed of movement and a preliminary tension of a tape of the conveyor.
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