CONWIP: a pull alternative to kanban

Re-Examining the Performance of MRP and Kanban Material Control Strategies for Multi-Product Flexible Manufacturing Systems

“…In addition, hybrid strategies that combine different features of push and pull have also been proposed in the literature. The CONWIP system proposed in Spearman et al (1990) and the POLCA system proposed in Suri (1998) are examples of such strategies. More recently, several researchers have proposed material control strategies that integrate advance demand information with pull control (Karaesmen et al, 2003).…”

“…Material control strategies that combine features of push and pull are referred to as hybrid strategies. Recently, several hybrid strategies such as CONWIP (Spearman et al, 1990) and POLCA (Suri, 1998) have been proposed.…”

Operational Management of Supply Chains: A Hybrid Petri Net Approach

“…Similarly, in the second operative condition the stored materials in the SC buffers are minimized and, if we wish to minimize the stocks of inventory of a sub-set of products, then (9) may be accordingly modified by a suitable vector c T . Moreover, the third operative condition aims at imposing an almost constant workinprocess in each buffer as a fraction of each capacity, similar to the previously described CONWIP management technique (Spearman et al 1990). In this case the storage costs are a priori limited and at the same time the SC does not evolve at its maximum productivity level.…”

“…Wellknown push systems are the Material Requirements Planning (MRP) approach and the Manufacturing Resources Planning technique (also known as MRP II) (Hopp & Spearman, 2004). Well-established pull strategies are the just-in-time technique based on Kanbans and the CONWIP (or CONstant Work-In-Process) strategy (Hopp & Spearman, 2004;Spearman et al, 1990), which is a generalized form of the Kanban policy: while the latter procedure establishes a fixed limit on work-in-process in a part of the system via the limited number of Kanban cards, the CONWIP strategy limits the total number of parts allowed in the whole system at any time, so that the SC is controlled at a constant level of work-in-process. Together with the operational planning and management policy, inventory systems play a very important role in SC management.…”

Toward learning autonomous pallets by using fuzzy rules, applied in a Conwip system

“…Therefore, a clever solution for dealing with such conditions is to employ advantages of several material flow control strategies [5]. For this purpose, some hybrid systems, e.g., Conwip, Polca, G-Polca, are practiced in several situations to overcome those problems [9,14,15]. It is claimed that these systems compensate the potential weaknesses of monopole systems and hinder them from getting failed or overproduction.…”