The ornamental design for a drum for washingmachine, as shown and described.
FIG. 1 is the front/right-side/top perspective view of a drum for washing machine showing our new design;
FIG. 2 is the front elevational view thereof;
FIG. 3 is the rear elevational view thereof;
FIG. 4 is the left-side elevational view thereof;
FIG. 5 is the right-side elevational view thereof;
FIG. 6 is the top plan view thereof;
FIG. 7 is the bottom plan view thereof; and,
FIG. 8 is the enlarged partial view of a cut-away portion with cross-sectional view of FIG. 1.
The dashed broken lines are for environmental purposes only and form no part of the claimed design. In particular, the dashed broken lines on the outside surface of the drum of washing machine shown in the figures represents unclaimed surface pattern.