| 摘要 |
The invention relates to a device for forming a collar around a hole in the wall of a pipe. The device comprises a rotary body (8) which in a plane perpendicular to the rotary shaft is elliptical in cross-section and in the plane of the rotary shaft substantially circular in cross-section. The body is provided with curved support surfaces (12) located in the plane of the rotary shaft, collaring means (14) being movable along said surfaces from an inserting position adjacent to the rotary shaft to a collaring position in a point on the body with the biggest elliptical cross-section. |
