And this in turn has other problems which were highlighted by Cusumano (1994). Firstly the time which is wasted while the vans are stuck in traffic jams, this can result in late deliveries, the inventory which is used in transporting inventory and lastly the scrap material which is wasted (e.g. petrol or diesel burned). JIT unconditionally presumes a level of input cost constancy such that it is advantageous to stock inputs at today's prices. If input prices are anticipated to rise storing inputs may be sought-after. The leading problem with Just in Time strategy is that it leaves the supplier and downstream consumers open to supply shocks and large supply or demand changes. For internal causes this was seen as a feature rather than a bug by Ohno, who used the analogy of lowering the level of water in a river in order to expose the rocks to explain how removing inventory showed where flow of production was interrupted. Once the barriers were exposed, they could be removed; since one of the main barriers was rework, lowering inventory forced each shop to improve its own quality or cause a holdup in the next downstream area." If the stock levels reach the minimum there are many consignments of the same part coming all over the day, there is a possibility that they may incur an interruption in the flow of supply. And thus to tackle this kind of problem the firm has to use many suppliers to have the desired goods at the required time. Toyota uses two suppliers in order to avoid any disruption in the course. Toyota believes in keeping up high value relations with its total supplier network. Therefore, a strong, long-standing relationship with a small number of suppliers is chosen to temporary, price-based relationships with contending suppliers. Toyota has also been using a durable relationship with its old suppliers. And they also send their workers to their suppliers to enhance the performance of the supply. This long-term relationship has also been used by Toyota to send Toyota staff into their suppliers to improve their suppliers' processes. These involvements are lasting for twenty years and therefore result in better margins for Toyota, the supplier and as well as lower final costs and a more consistent supply sequence. As noted by Liker (2003) and Womack and Jones (2003), it would finally be advantageous to establish coordinated flow and associated JIT all the way back through the supply flow. However, nobody followed this in detail all the way back through the procedures of the raw materials. Most of the raw materials cannot be grown or discovered instantly and hence require time in accordance with the weather and natural play. The part of JIT which is presently supposed to be impossible is the synchronized part of flow. However the part of this that is currently viewed as impossible is the synchronized part of flow and the linked part of JIT. However these two can be enforced in remote process islands within the raw materials flow. (Wikipedia)

Lean manufacturing is a general procedure management philosophy, which came up from the Toyota Production System (also known as TPS) and also from some other sources. It is well-known and popular for it centers on decreasing of the real Toyota seven wastes, in order to increase overall client value but has a number of latest key perspectives on how to do this. Lean is often associated with six sigma for the reason that the methodology's stress on reduction of process variation (or its converse smoothness) and Toyota's combined usage (with the TPS). The constant and permanent progress of Toyota company from a small manufacturing company to a leading and most popular car company stresses on our mind to find out what made it grow faster and with a constant speed. The answer is its different way of production and processes, the plans and the strategies; it had made "lean" a burning matter in management science in the first decade of the 21st century.

U.S. production firms always try to raise the profit margin and for the achievement of this goal they kept on seeking for effective policies that will improve or tend to improve the quality of output, decrease cost and build up a competitive place to enlarge their market share, beginning efforts can be associated to Eli Whitney and Henry Ford.

The Machine That Changed the World," a book written by James Womack in 1990. Womack's book was a clear-cut explanation of the history of automobile manufacturing joint with a study of Japanese, American, and European automotive assembly plants. The popularity of "lean manufacturing" theory in the factories of America was made in large part by the Massachusetts Institute of Technology lessons of the process from mass production toward production as written and described in Womack's book.

A new slogan was coined, as to which is now frequently referred to as "Lean Manufacturing." (Peterman, pg 24)

Peterman stated...

These consist of waste in several areas including: machine setup, inspection, waiting, storage, and transport, order dealing out, machine collapse and so on.
These activities often contribute to lower qualities. Examples include: damage during transportation, rework double handling; misidentification in storage; loss in storage; setup adjustments that results in a marginal product; breakdowns of machines instead of preventive maintenance; and inspection vs. process capability. The most awful waste of time, however, is usually a lack of communication or miscommunication among operators of different components during the procedure between raw material and the finished good. (Peterman, 2001, p. 24)

To manufacture a new product, lean manufacturing requires a reduced amount of everything in contrast with mass production: reduced waste, reduced human effort, reduced investment in tools, reduced manufacturing space and reduced engineering time. William M. Feld described five fundamental elements for lean management in the book "Lean Manufacturing" (p. 4).

Manufacturing flow: The aspect that address physical modification and design standards that are arranged as part of the cell.

Organization: The aspect focusing on people's roles/functions, training in new ways of working, and communication.

Process Control: The aspect directed at monitoring, controlling, stabilizing and pursuing ways to improve the process.

Metrics: The aspect addressing visible, result-based performance measures; targeted improvement and team rewards/recognition.

Logistics: The aspect that provides definition for operating rules and mechanisms for planning and controlling the flow of material.

Steve L. Hunter lists ten steps to put into practice a lean/JIT production system:

Reengineer the manufacturing system

Reduce setup

Integrate quality control

Integrate preventive maintenance

Level and balance the system

Integrate a pull system

Control inventory

Implement a vendor program

Utilize computer integrated manufacturing (CIM) benefits

It was noticed that stock lessening is not the only objective of lean/JIT implementation; it is a very noticeable advantage. Less workspace is now required due to the use of smaller lot sizes and reduced inventory levels. Much of this inventory was accumulated between and within work centers. By decreasing inventory, companies have been capable to essentially shift work centers closer together, freeing up space and reducing material handling distances. This falls in a neater, more structured facility that provides for speedy recognition of bottlenecks and fewer lost parts.

In addition, this reduction in inventory and lot sizes encourages quick feedback from downstream work centers when there is a quality crisis. This feedback results in a reduction in scrap and rework, and ultimately a higher level of overall quality. Reduced inventory and lot sizes also result in improved inventory turns. Inventory turn increases have been noted at Haworth (a twofold increase), Hewlett-Packard (a threefold increase), Richardson-Vicks Homecare Products (a threefold increase), IBM, Raleigh (a fourfold increase), and Harley-Davidson (a sixfold increase).

The introduction of precautionary preservation and the use of smaller, more flexible machinery combine to yield increased equipment consumption. One chief firm was able to change from three lines running three shifts to two lines running one shift with no change in output. Lean manufacturing methods have ended up in chief productivity enhancements and expenditure savings

Conclusion

Just in Time is rapidly getting fame in the world of business. People frequently articulate JIT as a 'Complete management'. It is designed to reduce waste, increasing cost proficiency, and achieving a reasonable profit. It helps in reducing the expenses of a company and emphasizes on the service provided to the customers. It believes in improving the quality and the delivery of the products. The cost incurred in the form warehousing and stockholding is also significantly reduced.

The lean/JIT producer combines the compensation of skill and mass production, while avoid the high cost of the past and the inflexibility of mass production. Lean/JIT manufacturers position their sights unambiguously on excellence: continually declining overheads, nil defects, nil inventories, and infinite merchandise range. Lean/JIT manufacturing is the fresh model for manufacturing, replacing a mass-production technique that has survived for more than 70 years. Lean techniques are applicable not only in manufacturing, but also in service-oriented…