The Supermarket

Just in time

"Just in time" was originally a management system used for manufacturing industry

JUST-IN-TIME (JIT) PRODUCTION

JIT is a management philosophy that strives to eliminate sources of manufacturing waste by producing the right part in the right place at the right time. Waste results from any activity that adds cost without adding value, such as moving and storing. JIT (also known as lean production or stockless production) should improve profits and return on investment by reducing inventory levels (increasing the inventory turnover rate), improving product quality, reducing production and delivery lead times, and reducing other costs (such as those associated with machine setup and equipment breakdown). By applying a JIT system, The supermarkets place pressure on the manufacturers to hedge against problems that may arise. The general idea is to establish flow processes by linking work centers so that there is an even, balanced flow of materials throughout the entire production process. To accomplish this, an attempt is made to reach the goals of driving all queues toward zero and achieving the ideal lot size of one unit.

Keys to Successful JIT Implementation

1. Stabilize and level the Manufacturing Production Systyem with uniform plant loading: create a uniform load on all work centers through constant daily production. Produce roughly the same mix of products each day, using a repeating sequence if several products are produced on the same line. Meet demand fluctuations through end-item inventory rather than through fluctuations in production level.
2. Reduce or eliminate setup times: aim for single digit setup times (less than 10 minutes) or "one-touch" setup -- this can be done through better planning, process redesign, and product redesign.
3. Reduce lot sizes (manufacturing and purchase): reducing setup times allows economical production of smaller lots; close cooperation with suppliers is necessary to achieve reductions in order lot sizes for purchased items, since this will require more frequent deliveries. The supermarket facilitates this via the internet link witht the suppier.
4. Reduce production and delivery lead times: delivery lead times can be reduced through close cooperation with suppliers, often via internet link up.
5. Preventive maintenance: use machine and worker idle time to maintain equipment and prevent breakdowns
6. Flexible work force: workers should be trained to operate several machines, to perform maintenance tasks, and to perform quality inspections. In general, the attitude of respect for people leads to giving workers more responsibility for their own work.
7. Require supplier quality assurance and implement a zero defects quality program: errors leading to defective items must be eliminated, since there are no buffers of excess parts. A "quality at the source" program must be implemented.
8. Small-lot (single unit) conveyance: use a control system such as a card system to convey parts between work stations in small quantities (ideally, one unit at a time).

The supermarkets have daily diliveries of goods they have much smaller store areas at the site this coists less to build. The use of JIT can however cause problems Most Supoermarkets are able to sell petrol cheeply becauise they can buy large quantities every day and keep little stock. When in 2000 protesters blocked the dilivery lorrys supermarkets ran out the next day wheras more traditional garages had a week to two weeks supply.

The advantages usually out weigh the disadvantages you never hear of a supermarket garage goping out of bussiness!

© LEV