Abstract: The invention relates to an apparatus for cutting an oval hole in the wall of a pipe. The pipe secured to a baseplate (1) of the apparatus is cut for an oval hole by means of a tool (20) having its cutter head (24) rotated about its axis while it is driven along a circular path in relation to a carriage (2) of the apparatus. The carriage (2) is mounted on the baseplate (1) by way of linear runners (3). Adapted for rotation along with a drive pulley (4) of the tool (20) is a cogged wheel (10), which through the transmission of a cam lever (11) is adapted to drive a shaft (12) having its rotational motion transmitted on the one hand to drive a gear (22) and on the other hand to work the carriage (2) back and forth in relation to the baseplate (1), a round-trip displacement (2xa) being equal to a difference between the major axis and the minor axis of a desired ellipse.

Abstract: The invention relates to an apparatus for cutting an oval hole in the wall of a pipe. The pipe secured to a baseplate (1) of the apparatus is cut for an oval hole by means of a tool (20) having its cutter head (24) rotated about its axis while it is driven along a circular path in relation to a carriage (2) of the apparatus. The carriage (2) is mounted on the baseplate (1) by way of linear runners (3). Adapted for rotation along with a drive pulley (4) of the tool (20) is a cogged wheel (10), which through the transmission of a cam lever (11) is adapted to drive a shaft (12) having its rotational motion transmitted on the one hand to drive a gear (22) and on the other hand to work the carriage (2) back and forth in relation to the baseplate (1), a round-trip displacement (2xa) being equal to a difference between the major axis and the minor axis of a desired ellipse.

Abstract: An apparatus and method for making an elongated hole in a pipe which includes drilling a rotating conical tool through the pipe wall by pushing the conical tool in the direction of its rotating axis to a desired depth, then simultaneously lifting and tilting the conical bit so as to mill one end of an elongated hole. The rotatable conical tool may be lifted and tilted in the opposite direction to further mill the pipe and elongate the hole. Tilting is effected relative to a pivot point located above the top pipe surface and in a plane extending through a center axis of the pipe, and the angle of inclination can be adjusted for determining the length of the finished hole.