The process of increasing the stable operation of the working body in crank presses

Abstract

The article considers the study of the synthesized concept of frictional contact of solids in crank presses. As a result of the analysis the possibility of obtaining the maximum load characteristic of the friction contact within the interval of variation of the friction coefficient has been established. The possibility of equality of the values of the friction force of the friction contact at the boundaries of the indicated interval in the presence of a maximum and the achievement of their greatest stability under these conditions is also revealed. As result the upgraded concept of frictional contact allows theoretically to obtain a very high stability of the friction force, however, due to the relatively large value of the angle and force parameter, it is used inefficiently. A necessary condition for the absence of zero reversal of the output parameter of the main friction group of the friction contact in the interval of variation of the friction coefficient and the presence of the maximum function of the load capacity of the friction contact is the transfer of its full load by the sensitive elements of the additional friction group. An additional condition for the existence of a maximum is the need for the sensitive elements of the main friction group to transfer part of its full load at an equal number of friction pairs of both friction groups, and for the sensitive elements to transfer the full load of the main friction group at a lower number of friction pairs than in the additional friction group.

Impact of environmental problems on human health and economy in the Russian Federation

“…Hydroconstruction, the withdrawal of a large amount of fresh water for irrigation and other economic needs, the operation of water intakes without fish protection devices, water pollution, excess of the catch quota and other factors have sharply worsened the condition and conditions of fish stock reproduction: fish catches are decreasing (a tense situation for the fish industry has developed in the basins rivers: Ob, Irtysh, Yenisei, Kuban The seas of the Far East are characterized by the disappearance of the sardine -ivasi and a reduction in pollock stocks, which is caused by unregulated foreign fishing; the disappearance of valuable fish species occurs, the oppression and death of many species of ichthyofauna (in the Volga, the natural spawning grounds of white fish have completely disappeared, only 12% of sturgeon fish survived; thickets of seaweed (kelp) in some areas of Primorye have disappeared; the incidence of valuable fish species and the accumulation of harmful pollutants in it are increasing (in the muscle tissues of sturgeons, there is an accumulation of chlororganic pesticides, with lei of heavy metals, mercury). The results of the check showed that organic compounds of pguty were found in 156 out of 193 fish samples from various parts of the Vetluga, Cheboksary and Kuibyshevsky reservoirs in concentrations from 0.005 to 1.0 mg / kg of fish weight [6][7][8].…”