164 Chapter 9

Manufacturing technology is the technology of process control. It is machines, human labor, and the organization of work brought together to control a manufacturing process. Whenever the approach to process control shifts significantly, many parameters change. These shifts suggest six epochs in manufacturing. The new technology dictates changes in the nature and organization of manufacturing, and in the machines used to effect those changes.

The English system of manufacture originated in the late 18th century with the invention of general-purpose machine tools, such as lathes, that could be used to fabricate a variety of workpieces. The American system of manufacture that emerged in the mid-1800s emphasized precision and interchangeability of parts.

The era of scientific management began in the late 1800s with the works of Frederick Winslow Taylor, a U.S. mechanical engineer whose principles of manufacturing management are known as Taylorism. Recognizing that the workers themselves were limiting the speed and efficiency of machines, Taylor claimed that these activities could be measured, analyzed, and controlled with techniques analogous to those applicable to physical objects. Using job analysis and time study, he determined a standard rate of output for each job. This approach placed control in the hands of management, which could monitor a worker's productivity by comparing his or her output against a standard.

Next came the era of process improvement, in the mid-20th century, based on statistical process control (SPC). Invented in the U.S. in the 1930s, SPC assumes that machines are intrinsically imprecise, since the identical procedure will produce different results on the same machine at different times. It emphasized «outliers» (out-of-control) situations rather than mean performance;

directed management's attention away from the worker toward machines. Whereas scientific management is concerned with manufacturing problems in essentially static forms, SPC is concerned with the dynamism of the processes.

Numerical control (NC) arrived in the 1970s with the microprocessor. NC combines the versatility of general-purpose machines with the precision and control of special-purpose machines. It emphasized adaptability above stability. It also implies experimentation, learning, place and nature of work.

Manufacturing entered the computer-

to shift — to change (in position or direction), move from one place to another укр. змінювати;

переміщати

lathe — укр. верстат

intrinsic — being part of the nature or character of

someone or something; Synonym: inherent укр.

внутрішньо властивий, притаманний за природою

mean— average укр. середній; звичайний;

пересічний

numerical control — укр. числове програмне

управління

versatile — having many different uses укр.

універсальний, багатоцільовий, різнобічний,

intelligence — укр. інтелект, розвинені логіко-

інформащйні можливості

extension — укр. продовження

cohesive — укр. згуртований

integrated era in the late 1980s. Computer-integrated manufacturing (CIM) is based on information about, and models of functional expertise that make it possible to examine and systematize the interactions among functions. Recognizing these interactions and predicting their consequences constitutes system intelligence. The systems enabled by CIM are extraordinary, to say nothing of versatility in the form of new products and processes.

Each of six manufacturing epochs focused on a particular aspect of process control — from accuracy, precision, and reproducibility to stability, adaptability, and versatility.

The first three epochs embraced mechanization, with manufacturing conceived in terms of increasing efficiency and control. The engineering focus was on machines, and labor was required to adapt to machines and, ultimately, to become yet another machine. Now the emphasis is on versatility and intelligence. Machines have come to be viewed as extensions of the mind that can enhance cognitive abilities of human beings. This shift, based on information technology, suggests new managerial imperatives (like building small cohesive teams), broadens the role of engineering management, and starts treating manufacturing as a service.