National Mineral Resources University (Mining University), Saint Petersburg, Russian Federation:

V. V. Buevich, Postgraduate Student, buevich.v@bk.ru

V. V. Gabov, Professor, gvv40@mail.ru

D. A. Zadkov, Associate Professor, dzadkov@yandex.ru

P. А. Vasileva, Associate Professor, polina_vasileva2013@mail.ru

The article discusses the possibility of adapting sections of mechanized roof supports to the variable geological and mining factors dealing with flat seams of medium thickness in longwall complex-mechanized coal face. Adaptation is provided by the rock pressure regulation of the pressure change rate in the piston cavities of hydraulic legs with static work load on the roof support. The proposed technical solution allows to separate process regulation function of rock pressure in the roof settling process from the protection function of the shields to be overloaded. Rock pressure regulation is provided by continuous regulation of fluid flow from the piston cavity into the complex hydraulic system which eliminates the sharp pressure drop in the elements of the hydraulic system sections, dynamic loads on the roof support in the regulating process. It also partly transfers potential energy of roof rock settling in the hydraulic system of the complex. Nonimpulsive rock pressure regulation leads to intensity decrease of crack formation processes directly in roof and rock caving in longwall face, to volume reduction of dangerous works stowing cavities formed over roof support, stability increase of coal mining technological process and safety works in coal faces. In the case of sharp roof block collapse at the limited capacity of an adjustable throttle, the piston emphasis in the top part of the pressure amplifier is provided in the block design. In this case pressure increase in piston cavity of hydraulic legs causing relief valve actuation in the protection mode against overloads is possible.

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