A mechanized work transfer system in which a robot assembly riding on a horizontal rail and driven by an external motor acts to convey a basket carrying work along a row of processing stages on a work bench. The assembly includes a robot provided with an elevator operated by an internal motor which serves to lower the basket at each stage on the work bench and to deposit it into a processing tank for a predetermined dwell period, after which the basket is hoisted out of the tank and transferred to another stage where the procedure is repeated. To render the assembly substantially immune to corrosive vapors emanating from the tanks, the robot housing is sectioned into left and right compartments, the left compartment being reserved for those moving and stationary components which can be fabricated of corrosion-resistant materials. The right compartment is reserved for the internal motor and other metal components which are vulnerable to corrosive vapors, this compartment being purged by a gas to prevent the entry of vapors therein.