What Are the Pros and Cons of a Flexible Manufacturing System?

Flexible manufacturing system refers to some equipment connected by a transmission system. The transmission device places the workpiece on other connection devices and sends it to various processing equipment, so that the workpiece processing is accurate, rapid and automated. The flexible manufacturing system has a central computer-controlled machine tool and a transmission system, which can sometimes process several different parts at the same time. ^[1]

Flexible manufacturing refers to a manufacturing system that can adapt to changes in processing objects with computer support. There are three types of flexible manufacturing systems:

Flexible manufacturing unit

A flexible manufacturing unit consists of one or more CNC machine tools or machining centers. The unit can automatically change tools and fixtures as needed to process different workpieces. The flexible manufacturing unit is suitable for processing complex shapes, simple processing procedures, long processing hours and small batches. It has greater equipment flexibility but lower personnel and processing flexibility.

Flexible manufacturing system

Flexible manufacturing system is a production system based on CNC machine tools or machining centers and equipped with material conveying devices. The system is automatically controlled by an electronic computer, which can meet the processing of multiple varieties without stopping the machine. The flexible manufacturing system is suitable for processing parts with complicated shapes, many processing procedures and large batches. Its processing and material transfer flexibility is large, but personnel flexibility is still low.

Flexible automatic production line

Flexible automatic production line is a production line that combines multiple adjustable machine tools (mostly special-purpose machine tools) and is equipped with automatic conveying devices. This production line can process large-sized parts of different specifications. The flexible automatic production line with low flexibility is close to the automatic production line for mass production; the flexible automatic production line with high flexibility is close to the flexible manufacturing system for small batch and multi-variety production.

Advantages of flexible manufacturing systems:

Flexible manufacturing system is a kind of technically complex and highly automated system. It organically combines technologies such as microelectronics, computer and system engineering, and ideally and satisfactorily solves the contradiction between high automation and high flexibility in mechanical manufacturing. The specific advantages are as follows.

1. High equipment utilization. After a group of machine tools are incorporated into the flexible manufacturing system, the output is several times higher than the output of this group of machine tools when the single machine is dispersed.

2. Work in process is reduced by about 80%.

3. The production capacity is relatively stable. The automatic processing system consists of one or more machine tools. When a fault occurs, it has the ability to degrade operation. The material transfer system also has the ability to bypass the faulty machine tool by itself.

4. High product quality. During the processing of parts, loading and unloading are completed at one time, the processing accuracy is high, and the processing form is stable.

5. Flexible operation. The inspection, mounting and maintenance of some flexible manufacturing systems can be completed in the first shift, and the second and third shifts can be produced normally without supervision. In an ideal flexible manufacturing system, its monitoring system can also deal with unforeseen problems during the operation process, such as tool wear and tear replacement, logistics blockage and dredging.

6. The product has great ability to respond. The cutters, fixtures and material transport devices are adjustable, and the system has a reasonable plane layout, which is convenient for adding or removing equipment to meet market needs.

7. Significant economic effects. The main technical and economic effect of adopting FMS is that it can arrange the processing of required parts in time according to the needs of assembly operations and achieve timely production, thereby reducing the inventory of blanks and work-in-process, and the corresponding working capital occupation, and shortening the production cycle; Improve the utilization rate of equipment, reduce the number of equipment and plant area; reduce the direct labor, can realize continuous "unmanned production" 24 hours a day and night under the condition of less care; improve the consistency of product quality.

The development trend of flexible manufacturing systems has roughly two aspects. ^[3]

FMS technology is based on group technology. It determines the process according to the group of processing objects, selects the appropriate numerical control processing equipment and the storage and transportation system of workpieces, tools and other materials, and is controlled by the computer. Batch efficient production of a variety of workpieces within a certain range (ie "flexible"), and the ability to change products in a timely manner to meet market demand.

FMS has two functions of processing and manufacturing and part of production management, so it can comprehensively improve production efficiency. The scope of FMS's process is continuously expanding and can include blank manufacturing, machining, assembly and quality inspection. Most of the FMSs put into use are used for cutting, but also for stamping and welding.