6. fine tuning of production using kanban

These rules are quite self-explanatory. For more information, refer to the reference indicated.

Other types of Kanbans

We also found three other types of kanbans that exist for special circumstances only.

They are discussed briefly as follows:

1. Express kanban - used when shortages of parts occur

2. Emergency kanban - used to replace defective parts and other uncertainties such as machine failures or changes in production volumes

3. Through kanban - used when adjacent work centers are located close to each other. It combines production and withdrawal kanbans for both stages onto one, through, kanban

Conclusion

There are many advantages to using the JIT philosophy.

Among the basic advantages of JIT are reduced finished goods and WIP inventory levels, shorter product flow times, and increased worker productivity allowing for lower production costs, and greater production customer responsiveness.

JIT objectives are met by using pull-based production planning and control systems.

The best known form of pull-control is our kanban control.

Kanban is a simple-to-operate control system, which offers the opportunity to delegate routine material transactions on the shop floor.

A number of attractive qualities contribute to the growing popularity of kanban control.

Kanban is simple (mechanically) and relatively inexpensive to implement and operate.

Simply determining the quantity and location of kanbans controls the amount of inventory.

It is a distributed control system, where complex system behavior is controlled by simple local rules.

Visual controls provide a direct form of communication and make clear what must be done by managers, supervisors, and operators.

Perhaps the most attractive aspect of kanban, and the one that often makes it difficult to implement, is its requirement for, and facilitation of, environmental improvement.

The reduction of WIP and visual control makes problems more noticeable.

This supports the saying that in order to eliminate waste, you must find it first.

The tighter coupling between processes creates a dependence, which is lacking in many push environments and forces awareness to problems.

Despite many sources of attractiveness, kanban control is not without its drawbacks.

Kanban is often cited as being applicable only in certain environments.

Issues of kanbans appropriateness in a particular production system revolve around general operating characteristics as well as environmental conditions.

The general operating characteristics required can be summarized as the repetitive manufacturing of discrete units in large volumes which can be held relatively steady over a period of time.

It is stated that kanban is difficult, or impossible to use when there are:

(1) job orders with short production runs, or

(2) significant set-ups, or

(3) scrap loss, or

(4) large, unpredictable fluctuations in demand.

Even spite these problems, kanban will be the system many companies will and should use in the near future.

Even in trying to establish an effective kanban, one must consider availability of relevant system information.

References

[1] Davis W.J. and Stubitz S.J. "Configuring a KanBan System Using a Discrete Optimization of Multiple Stochastic Pesponses," int. J. Prod. Pes., 25, 721-740, 1987.

[2] Philipoon P.R. Pees L.P., Taylor, B.W. and Huang P.Y., "Dynamically Adjusting the Number of Kanban Systems in a JIT Production System Using Estimated Values of Lead Time." IEE Yrans., 199-207, 1987

[3] Spearman M.L., Woodruff D.J. and Hopp W.J., "CONWIP: A pull Alternative to Kanban, Int. J. Prod. Res.. 28, 879-1566, 1990

[4] Singh, N. (1995) "Systems Approach to Computer-Integrated Design and Manufacturing" , John Wiley & Sons, Inc. page 630-631.

Kanban