METHOD OF BORING HARD ROCK BY MEANS OF TUNNEL BORING MACHINE

摘要

FIELD: mining.;SUBSTANCE: method of boring hard rock by means of tunnel boring machine equipped with disks of hardened steel projecting from cutting head consists in supply of foamed water liquid to cutting head; this composition corresponds to surface active substance -SAS and lubricating material - polyethylene oxide with molecular wt from 4.500.000 to 8.000.000. The said ingredients are measured separately in a water form, are added into water and are transformed into a foam using anionic or nonionic SAS; the said composition is obtained by dilution of concentrate with water on site.;EFFECT: reduced wear of cutting components; increased boring efficiency.;4 cl