Thermocorer for Rapid Drilling Tunneling and Excavating.

摘要

The potential of drilling bore-holes and tunnels by the dynamic kerf-melting technique is investigated. This technique, Thermocoring,uses an electrically heated tubular screw pump attached to a radially slotted annular flat drill-head,which resembles a shell end-mill with slot jets. The rotating screw heats and pumps the viscous lava through the drill-head. Experiments have demonstrated concept feasibility by dynamic kerf-melting 2in. diameter holes in low-melting-temperature,non-spallable rock simulants,such as solidified glycerin and fuzed salt,using inexpensive steel components. Advance rates of 2500ft/hr in solid hard salt were recently achieved using pumped molten salt,super-heated to 200C above its melting temperature. As a result, a new mechanism of melt drilling is hypothesized having measured energy requirements one-tenth those of direct bulk melting and offering the potential for advance rates in earth-strata far beyond present technology,with concomitant cost savings. As a result, Thermocoring may offer solutions to many of mankind's most urgent earth-centered ecological,scientific,raw material and energy supply problems.