Predicting Size Change From Heat Treatment

November 2, 2010

“By controlling the important variables, dimensional changes in heat treatment can be controlled.” Patrick McKenna

Variability is the enemy in our precision machining shops, and reducing variability is a key to sustaining our businesses and improving our capabilities.

When I talk about statistical process control with someone,  I listen closely to see if they are focused on the average (where the process is performing) or the standard deviation ( how the process is performing.)

If they are fixated on the average, I know I need to look at the data myself.  On the other hand if they are talking about standard deviations, I generally take their word on the data…

In the latest  issue of Production Machining Magazine, PMPA Technical Member Patrick McKenna from Nevada Heat Treating Inc., and Daniel Herring, the Herring Group Inc.  teach a nice class on how to reduce process variation in heat treat to minimize the post heat treat variability that all of us face.

Good advice here...

This is important if we are not to waste our production time trying to remove excess material because we left too much stock  for cleanup, or worse, finding the parts have shrunk in some critical dimension, rendering all of the parts ‘scrap.’

This article lists 9 variables NOT in control of the heat treater, and 14 that are under their control (furnace temperature uniformity, load configuration) or shared by the customer ( process selected, batch size, part size).

Not every order we produce is part of a long running job where we can control every input variable, but this piece does a great job of providing sensemaking on what can be a complicated and confusing subject.

I predict that you’ll keep this article in your “great to know” file.


Communicate Your Needs To The Heat Treater

June 10, 2010

The topic of  heat treatment is one part science and often it seems, two parts smoke and one part black magic.

Oh yes, and fire too.

If the definition of heat treating that you have is close to the definition of  steel that my neighbor has: “It’s dirty, it’s heavy, a magnet sticks to it and its made in fire,” then maybe you too could use an assist in figuring out how to communicate successfully with your heat treater.

We were pleased to see an article entitled ” How to Best Communicate Your Needs to the Heat Treater”  co- written by  PMPA Technical Member Nevada Heat Treating  Vice President Patrick McKenna.

It was feature article  in  the  April 2010 print edition of Industrial Heating magazine.

I predict that you will add it to your file of ‘articles you can use’ for sensemaking in this ever more complicated technical world that we harness for our customers.

You can read it at the link above.

Or contact Patrick at Nevada Heat Treating or Miles Free at PMPA and we’ll email you the article as a .pdf.

It will really be worth  your time before you send that next batch of parts out to take a ride through the Fire…


Nothing Is Made In The U.S. Anymore-FALSE!

May 27, 2010

“If U.S. manufacturing were a country by itself, it would be the eighth largest economy in the world.”

Guest post by Patrick McKenna, Vice President, Nevada Heat Treating, Inc. 

Heat treating what Americans make!

It happens to me fairly often. I’ll be at a party, or out to dinner with a group of people, and after someone in the group finds out I’m employed in manufacturing they will say “it’s really a shame that nothing is made in the U.S. anymore.”

It happened to me again last weekend. So I decided to look into the topic a bit more. I know we still make “things” here in the United States. I see it on a daily basis. Just how true is their comment that manufacturing has vanished in the U.S.?

I performed a little research on the topic and found the following statements in NAM’s (National Association of Manufacturers) “The Facts about Modern Manufacturing” 8th Edition (

“Between 1947 and 2008, both manufacturing GDP and overall GDP rose over sevenfold. It is generally unnoticed that the quantity of manufactured goods has continued to grow, leaving many people with the incorrect notion that little domestic value is produced in the United States anymore.”

“Manufacturing production is now at the highest point in its history and is keeping pace with that of the overall economy in terms of physical output.”

“…the quantity of manufactured goods produced in the United States has kept pace with overall economic growth since 1947, as both GDP and manufacturing have grown by about seven times.”

“Over the last ten years ending in 2008, manufacturing value added has increased 22 percent.”

Total manufacturing activity in the United States—measured in terms of physical output—continues to grow.”



The United States still has the largest manufacturing sector in the world, and its market share (around 20 percent) has held steady for 30 years.”
“One in six private sector jobs is still in or directly tied to manufacturing.”

“Fifty-seven percent of all U.S. exports are in manufactured goods.”
“If U.S. manufacturing were a country by itself, it would be the eighth largest economy in the world.”
“U.S. manufacturing share of global manufacturing value added has barely budged from its 1980 level of 22 percent.”


We lead the world in "making stuff"

 Is the U.S. manufacturing sector still facing challenges? Yes

Has China gained market share of the global manufacturing sector? Yes

Does U.S. manufacturing face increased pressure from legislation? Yes

The U.S. manufacturing industry has challenges like every other business sector, but to the people who say that manufacturing has disappeared, I would offer the following quote…
“The reports of my death have been greatly exaggerated.”– Mark Twain