PURPOSE: To prevent the interruption of operation due to the biting of a burr, etc., and to improve the operating efficiency of boring by using double core tubes for boring composed of a rotating core tube body and a separate auxiliary tube not turned.
CONSTITUTION: A cylindrical core tube 2, the inside of which is hollowed, the nose side of which is opened, at a nose of which a cutting blade 4 is fixed and which is made of steel, is installed to a shaft 6, and a cylindrical auxiliary tube 3, the inside of which is hollowed, the nose side of which is opened and which is made of steel, is fitted into the core tube body 2, and welded to a fixed shaft 5 and fastened, thus constituting double core tubes 1. When the core tube body 2 is rotated through the shaft 6 and a reinforced concrete structure 15 is cut by the cutting blade 4, the burr of a reinforcing bar cut is wrapped into the hollow of the auxiliary tube 3, and biting between the outer surface of a concrete post 18 cut and the inner surface of the main body 2 of the burr is prevented. Accordingly, the lowering of operating efficiency can be prevented.
KONDO NOBUHIRO
KAMIYAMA YOSHINORI
KAWASATO TAKESHI
HIRAGA TOMOAKI
| JPS603385A | 1985-01-09 | |||
| JPS4984295A | 1974-08-13 |