The ornamental design for a submersiblepump, as shown and described.
FIG. 1 is a perspective view of a submersible pump showing our new design;
FIG. 2 is a front view thereof;
FIG. 3 is a rear view thereof;
FIG. 4 is a right side view thereof;
FIG. 5 is a left side view thereof;
FIG. 6 is a plan view thereof;
FIG. 7 is a bottom view thereof; and,
FIG. 8 is a sectional view thereof taken along a line 8-8 in FIG. 2.
The broken lines included in FIGS. 6 and 7 are for the purpose of illustrating portions of the submersible pump and form no part of the claimed design.