The ornamental design of an pipe insertion apparatus, as shown and described.
FIG. 1 is a front view of an pipe insertion apparatus in cooperation with such pipe showing my new design, the rear view being a mirror image thereof; and,
FIG. 2 is a perspective view of the arrangement of FIG. 1.
The broken lines are provided for illustrative purposes only, and form no part of the claimed design. In addition, the portions of the arrangement for inserting the pipe that are not shown in the drawing do not form any part of the claimed design.