Sunday, January 23, 2011

Taylorism Applied to Metals Engineering

Frederick Winslow Taylor

Frederick Winslow Taylor wrote The Principles of Scientific Management in 1911 after decades of implementing his philosophy in diverse industries throughout the United States. It chronicles much of his method and the measurable gains that accrued to customers, employers and employees in the form of reduced prices driving increased consumption, a quadrupling of productivity and increases in wages of up to 70%.

Midvale Steel Company

Taylor’s account of his 1880 consulting engagement for the Midvale Steel Company is a powerful demonstration of quantitative methods’ potency. He quintupled productivity in the Metal Cutting department after collecting data, identified the 12 variables affecting metal work process time and distilled the information into several equations governing the processes.

Taylor first oversaw the collection of performance statistics for a specific metal-working machine, which would be the first of some ‘30,000 to 50,000 experiments’ conducted in an effort to reduce production times. A prerequisite for this task was identifying all pertinent variables… yielding the following:

Variables Affecting Metal-Work Processing Time

1) Type of material to be cut. i.e. ‘chilled iron’ or ‘very soft, low-carbon steel’
2) Chemical composition of the steel from which the tool is made.
3) ‘Thickness of the shaving… to be removed by the tool.’
4) ‘Shape or contour of the cutting edge of the tool.’
5) Is the tool water cooled or air cooled?
6) Depth of the cut.
7) Duration of the cut.
8) Lip and clearance angles of the tool.
9) ‘Elasticity of the work and of the tool on account of producing chatter.’
10) Diameter of the casting or forging which is being cut.
11) Pressure of the chip or shaving upon the cutting surface of the tool.
12) The pulling power and the speed and feed changes of the machine.

Taylor then derived several formulae which defined the relationships between these variables, for example:

          P = 45,000 D 14/15 F 3/4
          V = 90/T 1/8
          V = 11.9/ (F 0.665(48/3 D) 0.2373 + (2.4 / (18 + 24D))

At the time it was written though, it still required several hours of manual effort by a mathematician to solve these equations. A bottleneck which rendered their use infeasible because the cutting times were usually shorter than the calculation time. Another fifteen years of research were invested before slide-rules of approximating solutions were developed.


“By means of this slide-rule, one of these intricate problems can be solved in less than a minute by any good mechanic whether he understands mathematics or not, thus making available for every-day, practical use the years of experimenting on the art of cutting metals.”  The immediate benefit was improved productivity, but the magnitude of this improvement yields strategic implications...

The first company to derive these rules could maximize their throughput, maximize per worker productivity, and gain a significant advantage over their competitors. A competitive advantage that could not be duplicated without an exhaustive investment in data collection, years of experimentation and a spark of creativity surrounding the reduction of the formulae into slide rules.

Strategic Commentary

I am rather amazed reading this story because after deriving the laws governing the optimal cutting of metals and the creation of slide-rules to perform the computations, Taylor published his results in an academic journal! Even if Taylor wasn’t inclined to keep the information proprietary, I’m dumbfounded that Midvale permitted him to publish his results, thereby squandering any competitive advantage that could be gleaned. The book plainly indicates that the quantitative insights and use of the slide-rules quadrupled productivity and in some cases had a ten-fold increase! The owner of such knowledge could profitably buy competitors on the assumption that the productivity gains would pay for the purchasing premium (a la Cemex), or simply outprice their competition based on their productivity advantage (a la Carnegie Steel).

When all is said and done though, I guess that’s why Taylor is remembered as an engineer...  and not as an industrialist.

The Principles of Scientific Management by Frederick Winslow Taylor