The ornamental design for a pipehangar, as shown and described.
FIG. 1 is a top plan view of a pipe hangar showing my new design with the
bottom plan view being a mirror image, the exception being the direction
in which the vertically placed flange is turned;
FIG. 2 is a front elevational view thereof;
FIG. 3 is a side elevational view thereof with the opposite view being a
mirror image thereof; and,