Frequency converter of roof lowering control
Abstract
When studying the manifestations of rock pressure, the question often arises about the magnitude of deformations of the host rocks. For example, it is very important to determine the development of deformations in the remaining pillars and the roof of the chambers during the chamber and pillar system of field development. Many methods and devices are known for both direct and remote control of the magnitude of deformations of the host rocks, but they are not always applicable. In particular, it refers to the case when blasting operations during the clearance excavation do not give an opportunity to fix the beginning of the process of chamber roof lowering by the devices of direct control or remote control with the wire system of information transmission. To solve this problem we need devices, the placement of which will exclude the influence of blasting operations on their operability. This requirement is satisfied by the devices allowing measurements via radio communication channels. Therefore, the development of new radio-technical devices and methods of control, which will ensure reliability and safety of measurements of the magnitudes of deformation of the host rocks in production conditions, is of great importance.
References
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