Case Study - Examining All Operations in a Process

Case Study 27 of Industrial Engineering ONLINE Course
Industrial Engineering Case Studies Collection

The Process Chart is a device for visualizing a process as a means of improving it. Every detail of a process is more or less affected by every other detail; therefore the entire process must be presented in such form that it can be visualized all at once before any changes are made in any of its subdivisions (operations). In any subdivision of the process under examination, any changes made without due consideration of all the decisions and all the motions that precede and follow that subdivision will often be found unsuited to the ultimate plan of operation. - Gilbreth (1921). Process chart method was developed by Gilbreth.
Process Charts - Gilbreths - 1921

The illustration given below is based on the one given the book "Operation Analysis" by Maynard and Stegemerten

In a plant manufacturing large electrical apparatus,  certain copper segments were required to be bent to a radius. They were  first rough-bent on a bulldozer and then were formed by hand to the exact radius by a bench operation. The operation required many man-hours per each copper segment. A methods efficiency engineer was asked to study the job to reduce the time. As he examined all the operations of the process related to the copper segments, he found that the segments with the radii were transported to another department  six round bars were brazed to them. At the start of this operation, the brazer took a mallet and flattened the segments that were given the radius, thereby totally destroying the radius that had just been formed so expensively. After he had brazed the six bars in place, he bent the segments roughly to radius again and shipped them to the assembly floor. There they were assembled to the finished apparatus, and they functioned satisfactorily and no complaints were received from users.

The operation in current practice was developed to produce  the radius  to two decimal places that was specified in the drawing.  When the segments reached the brazer, he had difficulty in holding the six bars in place during brazing when the copper segment is in bent state.  The brazer,  an experienced man, based on his knowledge of the end use of the item was flattening the radius, brazing as required, and roughly bending them again. The segments performed their, function satisfactorily in the finished apparatus. This further processing of the items going on for months and years was not observed owing to the physical separation of the two department. It  was only  detected by  the  investigation of methods efficiency engineer during his study of the operation to reduce the time taken to do the operation.

Examining all operations,  subsequently became "Eliminate, Combine, Rearrange, Simplify - ECRS Method." The illustration above is an instance of elimination of an upstream activity based on the understanding of what is happening in the subsequent operations. Inspection requirement and process of final product inspection is also part of subsequent operations.

Updated 21 May 2021

Pub 13 June 2020