Education of the republic of uzbekistan tashkent state technical university named after islam karimov

№3/2021 year. 
Technical science and innovation
236 
The effect of sanding under the wheel on the shape of the adhesion characteristic has 
been studied relatively fully only for the growing branch (branch) of the adhesion characteristic.
The declining network of the coupling characteristic is crucial in calculating the 
processes of development and cessation of excessive slip of the wheels, the magnitude of which 
is determined for it only by the excess slip speed -. It follows that when moving with sand, it is 
possible to proceed from the description of a simple adhesion in the calculations, if the following 
are taken into account in the calculation
макс
хисоб
0
95
,
0



. 
A comparison of the traction description with the data of traction tests performed on 
locomotives and diesel locomotives shows that it is specific to any mainline locomotive. 
It can be argued that the thesis that the results of laboratory studies based on models in 
the CIS countries and abroad regarding the jump characteristics of the adhesion characteristic in 
the transition from an increasing or decreasing branch to an intermediate branch has been 
proved. The descending branch of the description, constructed on the basis of experimental linear 
(linear) test data, is shown in Figure 3 in the form of a solid curve. 
 
Figure 3. According to the experiments, the change of the coefficient of adhesion of 
the wheels in the zone of full slip at speeds from 5 to 40 km / h. 
______ - as the sliding speed increases. 
_ _ _ _ _ - 
as the sliding speed decreases. 
Its starting point 
1

k
corresponds to the value of However, it should also be noted that 
it is at this point that the description has the greatest rigidity: 
м акс
А



, this is reflected in 
[17].
In its initial part, i.e., at large but close values of, the curve is more oblique and, 
consequently, has larger values of than in experiments [15]. The difference is explained by the 
inaccuracies allowed in measurement and data processing. The error, in particular, due to the 
relatively less accurate measurement of wheel slippage in experiments, failed to obtain an 
experimental (experimental) network of coupling characteristics, which was therefore accepted 
in accordance with theoretical data and not taken into account. Therefore, the values obtained as 
a result of experiments [15] cannot be used.

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