THE CELL AND JIT

With greater emphasis on Just-In-Time (JIT) production, there must be the efficient use of all resources including people, material, equipment, and processes. The FMC concept provides additional flexibility and the dependable quality required for the production line.

Rather than following past practices of producing large quantities of finished products to keep in inventory, the trend today is to produce just enough product to meet the immediate demand. In a growing number of applications where this production technique has been implemented, experience has shown that the cost of converting to JIT using a well-designed cell is totally offset by reductions in inventory and corporate taxes.

Not only is changeover time minimal, but also JIT helps insure that quality parts are produced. Instead of the traditional 3-5% scrap and rework allowances, JIT results in no more than 0.5% scrap and rework because of the accuracy of the system and the reduced number of parts made to order.

JUSTIFYING CELLS

Before starting to justify a cell, the decision that a cell can meet the manufacturing requirement must be made. The decision should only be arrived at after a thorough investigation by management of all of the problems facing the company. Typically, such problems will include:

• Increased competition

• Inability to change rapidly to meet market demands

• Increased material costs

• Decline of skilled personnel

• Shortage of floor space to accommodate future production needs

Most accounting procedures are not set up to evaluate the true cost factors involved in an FMC installation. With these known inadequacies, management must develop new measurements with which to evaluate these investments. Besides the obvious benefits of increased productivity and reduced manufacturing costs, it is important to consider the hidden factors as well. These include improved product quality, improved material-handling efficiency, shorter setup and run times, less work-in-process, reduced inventories, and shorter lead times. Shortening parts manufacturing lead times can shorten the response time to customer orders and lead to smaller finished-goods inventories.

The return on the investment for a FMC cell, when properly set up and operated, should show positive results in a very short period of time. The strategic values in the marketplace will be an added bonus and will far outweigh the investment.

EFFECTS of CELLS on PURCHASING

Cell technology has a major effect on purchasing procedures. Because of shorter throughput and more predictable scheduling, purchased materials will be along the lines of Just-In-Time inventory. These procedures will affect the ordering procedures and the method of dealing with material suppliers.

Suppliers will be required to be more responsive to short-term, small-quantity orders, rather than the more traditional large quantities and long-term orders. This change can cause a hardship on the supplier, requiring a different type of contract if a good source of material to produce a specific family of parts is to be maintained.

FMC ADVANTAGES

• Improved use of capital investment through reduced material-in-process (MIP) eliminates the cost of having parts waiting at each machine station.

• The production philosophy of having more material than required, to cover rework and scrap, can be altered.

• Most machining operations will be completed within the cell, reducing the parts being queued in the manufacturing process.

• A company that previously used 22 machines to process 325 parts, now completed them with 7 machines in one cell reducing the work-in-process from 20-30% and raising output by 150%.

• The saving in setup reduction amounted to 35% and the operation was carried out in 15% less floor space.

• The cell improves product quality and reduces scrap and rework.

• Increased machine tool uptime, greater flexibility, improved quality, greater total productivity, and the elimination of part handling time.

• At least a 50% reduction in scrap and rework with the possibility of reducing this to near zero.

• Consistent quality levels and improved productivity from each hour of effort reduces the cost of labor.

• Indirect labor costs are much lower with the short movement of parts from machine to machine within a cell and the reduction of material storage.

Because of the faster throughput of manufactured parts, the most important feature of the FMC is its ability to rapidly react to market changes. The faster changeover of material reduces the possibility that a manufacturer will have a huge inventory of finished material if the market requires a different product or different model of current product.

The capacity for wider job variety and the need for higher skill levels are features of the cellular approach. This, combined with the opportunity for operator teamwork, leads to higher productivity and better quality.

For more information on GROUP TECHNOLOGY AND CELLULAR MANUFACTURING see the Websites: www.cv.com  www.glmachinetools.comwww.hmssoftware.com

Copyright 2004, Industrial Press, Inc., New York, NY