Abstract of theme: |
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Reasons of economy energy therewith elimination of roller skew belt conveyor |
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Master: Driga Ivan |
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Leader of work: Chebanenko Konstantin |
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Belt conveyer is the most productive transport vehicle applied on mining enterprises.
One of perspective directions in development of constructions of belt conveyers is application of rope support and underground joint rollers. Application of suspended support allows decrease labour intensive of editing of conveyer to 25-30%, to multiply the term of service due to reduction of straightforwardness of support and liquidation of litter lower branch.
At motion on rollers support the conveyer belt under action of different forces deviates aside from the central position, and arises up the phenomenon urgent lateral tails. Uncentral motion of belt and now is one of reasons of outage of conveyers, appearance of prosipey load and litter support, reductions of belt service term. It is set, that 13% of all surfaces of belt makes stratification of sides, arising up from friction of belt on firm support or fasten. The stratification of sides results, that a belt is taken off from exploitation in 10-12 months, thus often with bearing part fully capable of working. As a result of friction of sides of belt at the bars of support there is also their intensive wear, that results to reduction of width belt width. Reduction of width of belt lowers productivity of conveyer and multiplies strew of load. A question about the exact setting of support is important, because inexact setting is the reason of lateral tails of belt, which results in reduction of term of its service, litter support, promoted wear of rollers, to the increase of energy of portage. This work is devoted to solve this question.
At motion on rollers support a conveyer belt under action of different forces deviates aside from the central position, and arises up the phenomenon which in practice is named lateral tails. We will consider reasons resulting in appearance of lateral centring forces.
the process of exploitation of conveyer on a belt locomotive on linear part, the lateral forces are caused by the following factors operate:
-by slanting rollers in horizontal and vertical planes;
-by deviation of support from the axis of conveyer;
-by different resistance to the rotation of lateral rollers of support;
-by the uncentral load of belt;
-by straightforwardless of belt in the horizontal plan;
-asymmetrical distributing of pull on the width of belt;
-by a different pull of ropes of support.
Most uncentral factors can be considered, as static. For uncentral efforts and moments we will consider interaction of belt and rollers .
The process of interaction of locomotive conveyer belt with the twisted roller is a difficult process, in which it is necessary to take into account many factors: resilient properties of contacting surfaces; resistance to the rotation of rollers; forces, operating on a belt in direction perpendicular to direction of its motion; freedom of motion of belt and roller in various directions.
The corner of defect of the revolved roller does not determine the effect of lateral tails of ribbon fully; this effect is determined by the difference between the corner of defect and corner of absolute speed of ribbon (by the corner of running back of belt). In general case this difference of corners is not equal to the zero.
The corner of defect of roller at which comes slipping of belt, relies on force of coupling of its with a roller, resistances to the rotation of the last and the most important from forses, impedimental to lateral displacement of belt. Depending on the size of that or other from the adopted factors the maximum corner of defect can be different.
At determination of efficiency of action of centring turning rollers it is necessary to take into account all forces operating on a belt in transversal direction. One of such forces is force of resistance to the tails of belt on the normally set rollers.
The process of tails of belt on the conveyer is determined by not only revolting action of the twisted rollers but also parameters of all conveyer setting on the whole.
In literature, devoted to our theme, reasons causing additional resistance to motion of belt have been considered in detail, and also different cases of interaction of belt with the twisted roller have been considered. However the question has not been considered about additional resistance to motion by the caused defect of axis of roller in relation to the axis of belt and additional expense of energy.
This work the construction for the exact setting of rollers was developed.
Questions for definition resistances to motion of belt on twisted rollers decided for achievement of the given purpose, and the method of determination of additional resistance to motion on twisted rollers in a horizontal plan were developed.
For evident computation of additional resistance to motion on twisted is executed the rollers belt conveyer 4L1200D. At the corner of defect a 3 0 resistance from sliding on the loaded branch makes 40% basic, the empty branch 29% from basic. In the case of the exact setting of rollers it is possible to evade these losses.
Triangle allowing exactly to set rollers belt conveyer was developed.
The prosecution of diploma has not been completed yet.