The ornamental design for a chemicalmixingmachine, as shown and described.
FIG. 1 is a front perspective view of a chemical mixing station according to the invention;
FIG. 2 is a rear perspective view of a chemical mixing station according to the invention;
FIG. 3 is a front elevation;
FIG. 4 is a side elevation;
FIG. 5 is a top elevation;
FIG. 6 is a bottom elevation; and,
FIG. 7 is a rear elevation.
The broken line showing of the chemical mixing station is included for the purpose of illustrating portions of the chemical mixing station and forms no part of the claimed design.