Generic POLCA—A production and materials flow control mechanism for quick response manufacturing

Abstract

A production and materials flow control mechanism for quick response manufacturing (QRM) is proposed. This is called generic paired-cell overlapping loops of cards with authorization (GPOLCA). It is an adaptation of the POLCA mechanism developed as part of the QRM strategy. GPOLCA implements an input-output control order release strategy based on an inventory of production authorization cards instead of materials. It is best suited for companies that manufacture large variety of products with variable demand. A description of GPOLCA is made together with a comparative study of its performance in relation with other mechanisms namely MRP and POLCA. The results show that GPOLCA attains better performance.Keywords: Production control; Simulation; QRM; GPOLCA IntroductionIn today's changing manufacturing world with new paradigms such as mass customization and global manufacturing operations and competition, companies need greater capabilities to respond quicker to market dynamics and varying demands. The adoption of suitable production and materials flow control (PMFC) mechanisms, combined with the implementation of emergent technologies, can be of great value for improving performance and quality of manufacturing and of service to customers. Quick response manufacturing (QRM) can be an effective competitive strategy for companies that work on a make-to-order (MTO) basis of large product variety ranges with variable demand, or even for companies that work on a engineering-to-order (ETO) basis (Suri, 1998). QRM focuses on reducing lead times throughout all the production supply chain activities of an organization. Externally, QRM means responding to costumers needs by providing quick design and manufacture of products. Internally, it means reducing lead times for all tasks, improving quality, reducing costs and increasing the speed of response. PMFC strategies for QRM must address the need and the capability of firms to respond quickly to highly changing product demand requirements. This is usually not possible with inventory replenishment strategies such as the one implemented by the Toyota Kanban System (TKS), (Suri, 1998). Paired cell overlapping loops of cards with authorization (POLCA) is a hybrid push-pull PMFC mechanism developed as part of the overall strategy of QRM. According to Suri (1998), POLCA is a mechanism that overcomes the limitations of pull systems in high-variety and/or customization product environments, demonstrating its apparent relevance for the MTO and ETO sector. Suri (1998) uses the pull and push concepts as defined by Spearman and Zazanis (1992). These authors consider push systems as those that control throughput (TP) by establishing a master production schedule and measure work-in-process (WIP), and pull systems as those that control WIP and measure TP against the required demand. In this paper, a new PMFC mechanism, called Generic POLCA (GPOLCA) is proposed, to address QRM under MTO and ETO environments. The performance of GPOLCA is evaluated and compared with MRP and POLCA in...

Load-Based Generic Polca: Performance Assessement Using Simulation

“…[3,9], it is assumed that all materials are available and all necessary information regarding shop floor routing and processing times is known upon the arrival of an order to the shop. Orders flow into a pre-shop pool (or backlog) to await release according to the LB-GPOLCA method.…”

“…Two modifications proposed in the literature that resulted in increased effectiveness are Generic POLCA [3] and Load-Based POLCA (LB-POLCA) [4]. Generic POLCA changed the original loops structure of POLCA: a job cannot start processing on the first workstation (or cell) until all the cards for entire job processing are available to be attached to it.…”

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

“…Consequently, some special approaches to the existing material flow systems have been placed in order to handle requirements in one side and constraints on the other side. Therefore, some novel hybrid methods are introduced which combine the advantages of both material flow approaches as push and pull [8,9].…”

“…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.…”

Multi-item quick response system with budget constraint

“…Since 1990s quick response systems that enable the retailers to place two different orders with their suppliers before the selling season have been popular in supply chains of seasonal products such as fashion apparel, footwear, and toys (Fisher and Raman, 1996;Iyer and Bergen, 1997;Perry et al, 1999). Reducing lead times throughout all the production-supply chain activities is a primary focus of quick response manufacturing strategy (Fernandes and Carmo-Silva, 2006). Instead of placing a traditional single order, in a quick response setting, a retailer can implement the following strategy: an initial order is placed long before the selling season when the supplier is willing to commit to a low supply price, and a second order is placed at a time closer to the selling season when the retailer has a better assessment of the potential demand.…”