In the volume 38 of IIE Transactions (2006), Dolgui et al. introduced a line balancing problem in the machining environment, characterized by a number of particularities in comparison with the well-studied assembly line balancing problem, for example, parameterized operation times, non-strict precedence constraints and simultaneous operations performing. An exact method based on MIP formulation was suggested for solving small and medium size problems. In this paper, a number of effective pre-processing procedures are derived in order to decrease the problem size and reduce the number of variables and constraints. Their application allows solving even large-size problems to optimality. Experimental results are reported.