TAP HOLE EXCAVATION APPARATUS

摘要

PURPOSE: An iron notch excavating apparatus is provided to pulverize excavated refractories by generating relative rotation of a dual drilling bit, thereby facilitating removal of the refractories. CONSTITUTION: An iron notch excavating apparatus(50) comprises a dual rotation type excavating member(60) and a rotation transfer member(52). The dual rotation type excavating member has an excavating member having a dual structure where a drilling bit is included and is able to move relatively according to the rotation direction. The rotation transfer member is connected to the dual rotation type excavating member. The dual rotation type excavating member comprises a first rotation part(62) which excavates refractories corresponding to the outer circumference; a counter rotation connection keeping part(65) which keeps the connection between the first rotation part and the rotation transfer part in a relatively movable manner; a second rotation part(72) which is fixed to the rotation transfer part inside the first rotation part and excavates or pulverizes refractories. The counter rotation connection keeping part includes a spiral connecting part(66) which has a certain length and is installed on one end of the rotation transfer part; a cross section reduction part(67) which moves along the spiral connection part by using a screw thread for link with the spiral connecting part and is installed on the other end of the first rotation part; a front holding part and a back holding part which restrict movement of the cross section reduction part in the axial direction and is installed in the rotation transfer member.