EXCAVATION SCREW OF A JACK TUBE FORMING A REGULAR JACKING ROUTE AND SMOOTHLY DISCHARGING SOIL BEING ELIMINATED FROM THE UNDERGROUND

摘要

PURPOSE: An excavation screw of a jack tube is provided to improve a discharge of soil by preventing the soil from being accumulated on a jacking route and to prevent the surface deformation of the ground caused by the formation of the jacking route underground.;CONSTITUTION: An excavation screw(100) for a jacking pipe comprises a main screw unit(101), an inner screw unit(102), a rotary shaft(103), and an outer wing(104). The main screw unit comprises a through-hole(111). The inner screw unit is arranged in the inside of the through hole of the main screw unit. The inner screw unit comprises an inner wing(121). The inner wing is formed in to a spiral form along the outer circumference of the inner screw unit. The rotary shaft is connected into the inner screw unit, thereby rotating the inner screw unit and the main screw unit. The outer wing is formed into a spiral form along the outer circumferences of the rotary shaft and the main screw unit. The outer wing is rotated in the inside of a jacking pipe(110) as the main screw unit rotates.;COPYRIGHT KIPO 2012