Kanban systems

Pull scheduling. This ensures that production is pulled by demand and not just pushed, for example, by forecasts which may result in levels of stock that are either too high or too low. Pull scheduling is usually implemented through a simple but effective signal card system (the kanban system). 

In the remainder of this chapter, we first provide a more detailed discussion of JIT/TPS in Section 2, including its philosophy and implementation issues. In Section 3, we examine the kanban system, widely used in JIT for control of production and inventory, and present a case study of JIT/kanban implementation. Section 4 follows with an examination of JIT s relation to complementary approaches such as total quality management (TQM) and total productive maintenance (TPM), together with a case study of their joint implementation. In Section 5, we examine lean production as an extension of JIT, explore the relationship of JIT to theory of constraints (TOC), and conclude with a brief consideration of applications to service industries of JIT, TOC, and other manufacturing-based approaches. 

The Japanese term kanban simply means card or ticket. They are typically enclosed in a protective vinyl cover and contain the following information part number and name, process name where the kanban is to be used, number of units in the standard conteiiner and type of packing, number of kanban cards issued, preceding process outbound stockpoint number, and subsequent process inbound stockpoint number. There is a one-to-one correspondence between the cmds themselves and the standard parts containers that they represent. Furthermore, the cmds eilways circulate together with the actual material flow. Through the kanban system, workers understand their operations procedures and standards and learn and share the information required for process control. In this way, kanban functions as an information system as well as a means of visueil control. 

This tentative number of kanbans is reconsidered monthly because the daily leveled production requirement may differ under the new monthly production schedule. In addition, the number of kanbans is sometimes further reduced by systematically removing them from circulation in the system. The resultant reduction of work-in-process inventory will stress the production system and reveal the weakest point for further improvement. Thus, the kanban system is part of the approach used in JIT to move toward the goal of stockless production and achieve continuous improvement of the production system. 

As previously noted, the kanbtui system is particularly appropriate for high-volume, repetitive manufacturing environments. However, in comparison to the situation when the kemban system was originally created, many industries now face tremendous increases in the variety of pr ucts and parts coupled with lower volumes for each individueil item. This is seen also in the automobile industry, where more than 50% of parts now have their respective kanbans circulate less than once per day (Kuroiwa 1999). Such a low frequency of circulation leads to undesirably high levels of work-in-process inventory, and the kanban system ends up functioning the same way as the classic double-bin inventory system. 

Figure 5 Analogy of Drum-Buffer-Rope in (a) Theory of Constraints and (b) Kanban System.

Kuroiwa, S. (1999), Just-in-Time and Kanban System, in Seisan Kanri no Jiten, T. Enkawa, M. Kuroda, and Y. Fiikuda, Eds., Asakura Shoten, Tokyo, pp. 636-646 (in Japanese). 

Sugimori, Y., Kusunoki, K., Cho, E, and Uchikawa, S. (1977), Toyota Production System and Kanban System Materialization of Just-in-Time and Respect-for-Human System, International Journal of Production Research, Vol. 15, No. 6, pp. 553-564. 

TABLE 5 Comparison of Approximation and Simulation for p, , for a Kanban System with = 2... 

Chang, T. (1996), A Fuzzy Rule-Based Methodology for Dynamic Kanban Control in a Generic Kanban System, Ph.D. dissertation, Purdue University, West Lafayette, IN. 

Chang, T., and Yih, Y. (1998), A Fuzzy Rule-Based Approach for Dynamic control of kanbans in a generic kanban system, International Journal of Production Research, Vol. 36, No. 8, pp. 2247-2257. 

Sugimori, Y., R Cho Kusunoki S. Uchikawa 1977. Toyota production system and Kanban system materialisation of just-in-time and respect-for-human system. International Journal of Production Research, 15(6) 553—564. 

Kanban systems to pull product through the plant and the supply chain ... 

The two approaches will hone different skills. JIT will develop one type of capability — comprising manufacturing cells, kanban systems, and the like. Software solutions will develop another skill set — technology and system implementation. Both might reach the same end point eventually in terms of lead times and production flow. However, the skills... 

Kanban systems to pull product through the factory and supply chain. These systems create links between operations, notifying upstream operations when to move and make production units. The tool supports the demand-driven supply chain. 

In supply chain management (SCM), linkages play the roles of eon-ductor and sheet music. The SCOR model from the Supply-Chain Couneil is an example of one method for coordinating the supply chain. Another example, in the Toyota Production System, is the kanban system that signals the need for more parts. Proactive systems deseribed in Chapter 30 that use business rules to automate decision making are another example. The decision to use any particular technique at a point in time is an important supply chain design feature. 

Kanban Systems—it is an information system that is used to ascertain that production occurs when the demand is created downstream (www.fibre2fashion.com). Kanban is a system to control the logistic chain from a production point of view, and is not an inventory control system. Kanhan as a tool in lean manufacturing to achieve IfT. 

Kanban literaUy means card . Originally developed by Toyota in the 1980s, a Kanban was usually a printed card in a transparent plastic cover that contained details of specific information such as part number and quantity. It is a means of pulUng parts and products through the manufacturing or logistics sequence as needed just-in-time . Most Kanban systems are now computerized. Kanban is fully explained in Chapter 13. 

A Kanban system may nse either a single card or a two cards (move and pro-dnction) system. The dual card system works well in a high up-time process for... 

The system has been modified in many applications and in some facilities although it is known as a Kanban system, the card itself does not exist. In some cases the empty position on the input or output areas is sufficient to indicate that the next container is needed. 

The company adopted for each product, a simple single card Kanban system consisting of five stages as shown below (Figure 13.2). 

The pilot exercise was successful. It achieved an improvement in customer service which rose from 84 per cent to an excellent 98 per cent and inventory was also reduced. The Kanban system was extended to nine additional key products. The manual system was retained for the above five stages, although both the planning and stock adjustment processes were supported by MFG-Pro, the ERP system. 

Kanban It is a Japanese word for card. The basic kanban system is to use cards to trigger movements of materials between operations in production so that a customer order flows through the system. Computer systems eliminate the need for cards but the principle is the same. As a job flows through the factory, completion of one stage of production triggers the next so that there is no idle time, or queues, between operations. Any one job can be tracked to determine the stage of production. A Kanban is raised for each customer order. The kanban system enables production to be in batches of one. 

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