Abstract
The paper focuses on project scheduling classification issues according to the type of constraints and optimization directions. Special attention was paid to production scheduling, presenting the basic issues in relation with product flow organizational criterion. Open-cluster issue was formulated and analyzed with the use of modern heuristics. Solution was evaluated with multiple criteria, mainly on the basis of time characteristics. Production process flow relations, in coordinates determined by operation sequence at particular workplaces, as well as the production type factor were presented.