Automatic ear-hanging machines have been developed recently in order to reduce amount of manual labor in scallop aquaculture. This paper present theoretical and numerical analysis of conditions for production cost reduction. Operating inferiority concept of MAPI (Machinery and Allied Products Institute) was used in calculation model of the production cost calculation. Then, required minimum throughput qmin (g) and operation time rtmin, (g) was presented as functions of amual inferiority gradient g. Numerical analysis allowed finding out the following figures : 1. Estimates of the upper and lower values of amual inferiority gradient, gmax and gmin. 2. Mechanization is effective when amual inferiority gradient of the machine meets the condition :
