METHOD AND COMPOSITION FOR REDUCING WEAR IN A CUTTING HEAD OF A TUNNEL BORING MACHINES

摘要

A METHOD OF REDUCING WEAR IN A CUTTING HEAD OF A TUNNEL BORING MACHINE, BY MEANS OF THE ADDITION AT THE CUTTING HEAD OF A FOAMED AQUEOUS LIQUID COMPOSITION, WHICH COMPRISES A FOAMING AGENT AND A LUBRICANT, THE LUBRICANT BEING SELECTED FROM THE GROUP CONSISTING OF HIGH MOLECULAR WEIGHT POLYETHYLENE OXIDES AND BENTONITE. PREFERRED FOAMING AGENTS ARE ANIONIC AND NONANIONIC SURFACTANTS. WEAR RATED OF CUTTING ELEMENTS OF TBMS BORING IN HARD ROCK ARE CONSIDERABLY REDUCED. A WEAR-REDUCING FOAMABLE CONCENTRATE IS ALSO DESCRIBED.