Operation Management

Case study Making Hotplates

A group of 10 workers were responsible for assembling Hotplates (instruments for heating solutions to a given temperature) for hospital and medical laboratory use. A number of different models of hotplates were being manufactured. Some had a vibrating device so that the solution could be mixed while being heated. Others heated only test tubes. Still others could heat solutions in a variety of different containers.
With the appropriate small tools, each worker assembled part of a hotplate. The partially completed hotplate was placed on a moving belt, to be carried from one assembly station to the next. When the hotplate was completed, an inspector would check it over to ensure that it was working properly. Then the last worker would place it in a specially prepared cardboard box for shipping.
The assembly line had been carefully balanced by industrial engineers, who had used a time and motion study to break the job down into sub assembly tasks, each requiring about three minutes to accomplish. The amount of time calculated for each sub assembly had also been “balanced” so that the task performed by each worker was supposed to take almost exactly the same amount of time. The workers were paid a straight hourly rate.
And also the partially completed hotplate was placed on a moving belt, to be carried from one assembly station to the next. When the hotplate was completed, an inspector would check it over to ensure that it was working properly. Then the last worker would place it in a specially prepared cardboard box for shipping. The assembly line had been carefully balanced by industrial engineers, who had used a time and motion study to break the job down into sub assembly tasks, each requiring about three minutes to accomplish. The amount of time calculated for each sub assembly had also been