A heuristic approach for U-shaped assembly line balancing to improve labor productivity

The assembly line balancing problem is a non deterministic polynomial type planning problem for mass production. Layout design changes constitute a major decision that yields investment for assembly operations and numerous heuristics have been reported in the literature for solving the line balancing problems. U-shaped assembly layout offers several benefits over traditional straight-line layout in implementation of lean manufacturing and Just-In-Time technology. In the paper an attempt has been made to evaluate labor productivity in U-shaped line system and straight line system. A Critical Path Method (CPM) based approach for U-shaped assembly line has been applied for assigning the task to the work stations for assembly line layout. Results show that the CPM based U-shaped approach performs better and improve the labor productivity of assembly line layout.