Push and pull production systems: Issues and comparisons

Concerns about American manufacturing competitiveness compel new interest in alternative production control strategies. In this paper, the authors examine the behavior of push and pull production systems in an attempt to explain the apparent superior performance of pull systems. They consider three conjectures: that pull systems have less congestion; that pull systems are inherently easier to control; and that the benefits of a pull environment owe more to the fact that WIP is bounded than to the practice of ‘pulling’ everywhere. The authors examine these conjectures for analytically tractable models. In doing so, they not only find supporting evidence for the present surmises but also identify a control strategy that has push and pull characteristics and appears to outperform both pure push and pure pull systems. This hybrid system also appears to be more general in its applicability than traditional pull systems such as Kanban.