The study of melting process of the new plugging material at thermomechanical isolation technology of permeable horizons of mine opening

The article presents the results of experimental and theoretical
studies, the purpose of which was to substantiate the technology of drilling
wells isolation using new thermoplastic composite material. The basis of
the proposed material is gravel, and secondary polyethylene terephthalate
acts as a binding material. The use of the proposed insulation material
avoids a number of disadvantages specific for traditional grouting mortars.
The technology of material application provides its melting in a well by
thermomechanical drilling. The article deals with the issues, related to the
substantiation of the optimal formulation of a thermoplastic composite
material based on secondary polyethylene terephthalate, and the
determination of rational operating parameters of thermomechanical
drilling, which allow to melt effectively the material at the bottom of a
well. The possibility of material application for the insulation of absorbing
horizons in borehole conditions has been proved. Based on the analysis of
the heat balance at the bottom of a well, the calculation procedure has been
proposed and the dependences of the velocity and time of
thermomechanical melting of the grouting thermoplastic composite
material on the operating parameters of drilling, thermal properties and
geometric characteristics of the drill bit, have been determined.