摘要 |
A stabilizing attachment for a boring head is provided. The attachment includes a clamp for engaging a rotatable head plate of the boring head, a pair of support arms extending axially of the annular clamping ring, and a transverse plate carried by the support arms at their outer ends. The transverse plate supports a shaft on which is mounted an anti-friction bearing, the outer race of which engages an opening in the wall of a pressure vessel. A bit carried by the head plate of the boring head moves in an annular path to cut a gasket seat about the opening. A method of cutting an annular groove in a wall, utilizing a stabilizing attachment for a boring head which engages in an opening in the wall. |