VI. Speaking.

Discussion points:

1. The future of manufacturing.

2. Benefits of flexible systems.

3. Types of cells.

4. Structure of a cell.

5.The importance of manufacturing flexibility for a future factory.

6. The main criterion for effectiveness of manufacturing flexibility.

UNIT 8

FLEXIBLE MANUFACTURING SYSTEMS

I. Reading.

Ex.1. Read the text and translate it.

BENEFITS OF FLEXIBLE MANUFACTURING SYSTEMS

1. There are benefits to be obtained through the use of FMS technology:

High Capital Equipment Utilization

Typically, the throughput achieved for a set of machines in an FMS will be up to three times that achieved by the same machines in a stand-alone job shop environment. The FMS achieves high efficiency by having the computer schedule every part to a machine as soon as it is free; simultaneously moving the part on the automated material handling system and downloading the appropriate NC program to the machine. In addition, the part arrives at a machine already fixtured on a pallet (this is done at a separate load station) so that the machine does not have to wait while the part is set-up… (A).

2. Reduced Capital Equipment Costs

The high utilization of equipment results in the need for fewer machines in the FMS to do the same work load. Reduction of 3: 1 is common when replacing machining centers in a job-shop situation with an FMS… (B).

3. Reduced Direct Labor Costs

Since machines are operated completely under computer cont­rol, machinists are not required to run them. The only direct labor involved is that of less skilled personnel to fixture and de- fixture the parts at the load station, plus a system supervi­sor. However, labor cost reduction is somewhat offset by the need in the factory for skills which may not be currently present, such as computer specialists… (C).

4. Responsiveness to Changing Production Requirements

An FMS has the inherent flexibility to manufacture different products as the demands of the marketplace change or as en­gineering design changes are introduced… (D). Also, required spare part production can be mixed in without significantly dis­rupting the normal FMS production activities.

5. High Product Quality

The high level of automation, reduction in the number of fixturings and the number of machines visited, better de­signed permanent fixtures, and greater attention to part/mac­hine alignment all result in good individual part quality and excellent consistency from one workpiece to another. This also results in greatly reduced costs of rework… (E).

6. Operational Flexibility

Operational flexibility offers another increment in producti­vity. In some systems, the FMS can run virtually untended during the second and third shifts. This nearly «unmanned» mode of operation is currently the exception rather than the rule. But it should become increasingly common as better sensors and computer controls are developed to detect and to handle unanticipated problems, such as tool breakages, part flow jams, etc. In this operational mode, inspection, fixturing, and maintenance can be performed during the first shift.

7. Capacity Flexibility

With correct planning for available floor space, an FMS can be designed for low production volumes initially and, as de­mand increases, new machines can be added easily to pro­vide the extra capacity required.