Is there a final authority for the definition of engineering terms?

Maybe something like The Handbook of Chemistry and Physics or the AWS (American Welding Society) but for engineering.

I tried NIST and ASME. Search on Google and similar was surprisingly unhelpful.

Basic engineering texts have been suggested but they can differ.

Thanks,

Tom Walz

Thomas J. Walz
Carbide Processors, Inc.
www.carbideprocessors.com

Good engineering starts with a Grainger Catalog.

A court of law will define it for you - if you ever get in trouble......

Do you have specific terms in question? I think you're chasing a wild goose in general; there's nothing like a BIPM for just terms. The French had attempted to "standardize" their language and prevent bad words, like "hamburger" from entering their lexicon and failed miserably.

TTFN
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No.

"final authority" = god ?, or in his/her absense, the customer

Originally it was a discussion about running band saws. The terms 'stress' and 'strain' were being used. Everything got sidetracked discussing what each term meant.

I was hoping for a set of definitions from a highly authorative source.

Tom

Thomas J. Walz
Carbide Processors, Inc.
www.carbideprocessors.com

Good engineering starts with a Grainger Catalog.

there are different definitions for stress and strain, based on the reference area ...
true stress is based on the true area (eg, in a tension specimen the material necks, reducing the area)
engineering stress is based on the original area.

similarly for strain.

these should be well defined in pretty much any text.

tomwalz,

The terms "stress" and "strain" are defined in your mechanics of materials textbook. Perhaps there is some question as to what kind of stress and strain it is.

The phrase "stress and strain" is used with gay abandon all over the place by non-technical people, and it means whatever they choose it to mean, neither more or less.

--
JHG

I'm probably also guilty of misusing stress and strain in non-engineering conversations.
It seems absurd that a group of engineers could deliberately misuse the words after correction and not realize the difference.

ASTM E6 Standard Terminology Relating to Methods of Mechanical Testing defines stress and strain and similar terms.

http://www.astm.org/Standards/E6.htm

ASTM has multiple terminology standards, as do other organizations like ISO.

The problem is that we tend to use English words that have other meanings in other contexts. If strain was called, "Wapbamboop," one could safely define the word and concept and expect some level of consistency; it's just that no one would remember the word itself.

So, it's a double-edge sword; you can use words that have connotations that relate to your particular definition and risk a continually morphing definition, or you can use word that has no other definition, and risk people not remembering the word, and therefore, not using that word anyway.

However, it's the nature of language to evolve, even for very specific engineering terms. People use the term CDROM all the time, but really don't have any idea what the acronym means. That's evident when you see an R/W CDROM being advertised...

TTFN
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IRStuff,
As I read this thread I was composing my answer, then saw that you had given my answer so the best I can do is a star for you.

This discussion is the reason that every contract has a "definitions" section. If a term is material to understanding then you define it and both parties sign and that is the definition for the duration of that contract. Next contract the same terms can have different definitions. Fundamentally if you can't express a concept mathematically (which you can with "stress" and "strain") then it is subject to interpretation, confusion, and manipulation.

David Simpson, PE
MuleShoe Engineering

"Belief" is the acceptance of an hypotheses in the absence of data.
"Prejudice" is having an opinion not supported by the preponderance of the data.
"Knowledge" is only found through the accumulation and analysis of data.

Wapbamboop? Thank you IRStuff, I needed that just now.

Good on ya,

Goober Dave

Haven't see the forum policies? Do so now: Forum Policies

We can't even keep acronyms straight, even the ones we created within the company. Generally, within a couple of years, the original meaning of an acronym has faded into the dim mists of history. Not all documents create acronym tables, and not all documents are readily searchable for acronyms.

Most well-organized defense contracts have a "System Requirements Review" for the purpose of ensuring that the customer and contractor are on the same page with respect to the meaning and intent of each specification paragraph. The end result of that is often a specification interpretation document, to ensure that "I know that you believe you understand what you think I said, but I’m not sure you realize that what you heard is not what I meant" doesn't occur. Of course, that's often wishful thinking, at best.

I've come to the conclusion that engineers ought to have minored in English if they ever expect to run into a specification, just so that they have at least an inkling of what a requirement really says or means.

TTFN
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That's all fine but "stress" and "strain" are not acronyms. And yes, they have different meanings in different fields, medical for example. In the engineering field, their definitions come from the equations and formulas used to calculate them. They are two different but related things. Think of it this way: stress is a measurement force and area; strain is a measurement of length, or change in length. When you stretch a rubber band the stress is the "force" or "pressure" it feels. The strain is the amount it stretches.

We can't even settle on what "engineering" means around here.

Quote (IRstuff)

The problem is that we tend to use English words that have other meanings in other contexts. If strain was called, "Wapbamboop," one could safely define the word and concept and expect some level of consistency; it's just that no one would remember the word itself.

...

You should read up on the Underground Grammarian, the late Richard Mitchell. His book Less Than Words Can Say, is linked on the site. In it, he argues among other things, that people copy terminology from people they admire. Michell did not use the example of "stress and strain", but his reasoning still works. Someone will talk about the stresses and stains of a relationship, because they admire the precision and repeatability of what architects and engineers do. Any other cool terminology you invent will be copied accordingly.

--
JHG

Possibly, but I think if Mitchell implied the latter, it's a bunch of crock. "Stress" predates any modern usage related its engineeing usage: http://machaut.uchicago.edu/?resource=Webster%27s&...

If anything, it's the other way around. Engineers, being efficient people make use of existing words that fit the concept, rather than inventing new words. Even then, new words are often morphed from existing words or combinations thereof. Case in point: "computer" meant a human being given a task of performing mathematical calculations, until it got morphed into describing an electrical circuit that did the same, "transistor" is a combination of "transfer" and "resistor." "Resistor" has its roots in "resist" which predates any electrical engineering usage: http://machaut.uchicago.edu/?resource=Webster%27s&....

I do agree with Mitchell that people do tend to use new phrases as a kind of wave propagation phenomenon, e.g., "at the end of the day," which became quite popular, got overused, and is now roundly shunned. But, I'm not convinced that it's an overt process as described; I think it's more of a peer pressure thing, or overexposure in the media, as opposed to deciding on Monday to copy the speaking style of the Prime Minister of GB, since he was hardly "admired," even on a good day.

TTFN
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I use "McGraw-Hill Dictionary of Scientific and Technical Terms."

Charlie
www.facsco.com

Y14.38 is a start for acronyms but doesn't go as far as you're talking.

In the electrical world we have the IEC 60050 series of standards, which is also published online as the International Electrotechnical Vocabulary. I am not unsure if an equivalent exists for other disciplines.

The title should probably be changed to "International except the USA Electrotechnical Vocabulary". The US could then publish its own "International Electrotechnical Vocabulary" for domestic use.

are you out there Tom ?

is this good stuff, or not ?

I'm here and appreciative.

I had hoped something would gel into a generally accepted opinion.

Here is the problem I am trying to solve. I work with plant floor people in sawmills, etc Many of these people are very bright but are not engineers. Often they will describe the problem in the best terms they know and an engineer will tell them that what they are describing is impossible. This usually ends the discussion with the plant floor people feeling humiliated. However the machine still runs wrong and the plant still makes bad lumber.

I was looking for the ultimate reference to so that plant floor guys would not be put down because of their vocabulary.

The problem with this thread is that it seems to be full of intelligent, sophisticated people who are well aware of the problems involved.

My impression is that the folks here listen politely to mechanics, maintenance people, customers, etc. These people seem to work out a mutual definition of terms that is situation specific and they seem to do it without embarrassing anyone.

So it is not really a technical problem but a people problem.

Tom

Thomas J. Walz
Carbide Processors, Inc.
www.carbideprocessors.com

Good engineering starts with a Grainger Catalog.

" folks here listen politely to mechanics, maintenance people, customers, etc"

You left off wives

TTFN
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Ooh IRstuff, that's a bit sexist shouldn't it at least be spouses

tomwalz - any chance you could come up with your own glossary of terms and distribute it? Maybe have it on your website or similar? This way you could customize to your situations - maybe give fairly relevant examples.

Tom

Kenat more or less hit on the nail.
being it's a lumber saw mill,
I find that most of the floor people are very bright & will try to help.
the terminology should be easy to teach those that are willing to learn.
that is the key. some will not want to be bothered by it.

I have been one of the guys who has too suck it up & listen to what the floor needs are.
and yes the problem with some engineers is lack of humility.
& some floor personnel are just plain hard to work with.

Management must make the effort to have classes of what needs to be learned.
otherwise you are in boat with no paddle trying to scoot up stream.

Mfgengear

The problem here Tom, is that you are trying to be a sociologist and not an engineer. Why are you even attempting to change the climate of culture with your trades people? Does their terminology really matter? Your job is to engineer a solution that will solve certain issues, hopefully making your plant more profitable.

Strain is simply elongation or deformation over initial length, hence a unitless number. Stress is simply force over area, can be normal or shear. End of story. As mentioned by a number of knowledgeable individuals in this forum, stress and strain are mathematical formulations of a particular physical phenonema, hence have a pointed, well defined value. This is first year engineering, statics or equivalent.

I just can't see educating people with engineering terminology as a viable solution to the plant cranking out a crappy product. Mind you, that problem is self correcting, when your competitors gain market share, your plant will most likely get dismantled and shipped to some third world nation.

Problem solved.

Regards,
Cockroach

Cockroach

What Tom is trying to resolve is process improvement, so his plant does not close down.
I give Tom A+ for trying, instead of some who do nothing.
Thats what separate the people who excel.
give more than 100% of what is needed.

Thats All
Mfgenggear

Tom:

Wow... what a change in meaning or direction for a thread..., from your OP and your 17AUG12, 14:58 post to your 21AUG12, 14:04 post. Even you have trouble expressing your problem in terms we can all understand, almost like the “plant floor people” I don’t think you want an exact meaning for every tech. term in the world. You want some discussion about, or a method for, how you come to a meeting of the minds with two people who speak different lingos about the same general topic or problem. Be a real good listener, and keep drawing them out, everyone likes talking about what they think they know, and they won’t walk away feeling humiliated. Don’t “tell them,” rather keep ‘asking them’ to clarify because you don’t understand that term or their meaning. Maybe you even have to kinda play the dumb one for the moment; what does he think is causing that problem, what if he did this or that, what does he think the result would be, etc. etc. Leave them with the certain/absolute feeling that you want to help them solve their problem, not just sell them another band saw blade.

You’ve touched on a universal problem which we all have to deal with, whatever the levels of the interacting parties. Look at it this way, if you are the guy who knows the most about the topic under discussion, you have to be the teacher, without being condescending. Again, be a good listener, those guys have a lot to teach us and tell us. Parrot their comments and thoughts back to them, using your own terminology, maybe more technically correct terms, but maybe some completely different term which you think will cause a meeting of the minds. You’re trying to get ‘what-cha-ma-callit’ and stress to mean the same thing in this particular discussion. Come across as wanting to learn and understand their problems, whatever terminology they use. Ask lots of questions to draw them out, make them explain the same problem from slightly different angles. Do this a number of times, in part because you are not sure you understand what they are getting at. If all his answers or explanations point in the same direction or to the same conclusion, then you know you are getting someplace, a meeting of the minds, whatever they call it. Then explain his problem back to him, as you understand it, to see if he agrees, despite your crazy terminology. Again, inform and teach them the correct terms, gently please. Use real life examples (i.e. the rubber band by Jboggs, 20AAUG, for stress and strain) and sketches, grading crayons on slabs work fine, sometimes.

Draw him out, ask him to explain it another way, and keep asking questions or for clarification as soon as you think your thinking is not paralleling his. Maybe don’t insist on exactly correct terminology, because you may not get it. You do have to have fairly simple definitions and explanations of the terminology you are using when asked. Obviously, you have to know your own business well enough to make it mesh with their’s or with their problem. I’ve always looked at good craftsmen and workers, with admiration, for what they make look so easy, for what they know so well and for what I can learn about what they are doing. And, we all face these same problems, whether it’s a carbide tipped band saw blade which isn’t tracking or running true, or a machine part or weld which keeps breaking, or a beam which vibrates or deflects too much. And we have to draw that other party out because, as likely as not, we don’t speak exactly the same lingo. And, it isn’t a “highly authoritative source” which will solve this problem btwn. people from such different backgrounds, but rather coming to a meeting of the minds about what the problem is, with some real finesse, whatever they call it. Of course, we have to be humble in our interactions too, so we don’t come across as know-it-all jerks.

I have lurked this thread since the OP. I wanted to post this, but thoughtI might come off sounding like a Smart Alec. However, after Tom's last post, I think it applies.

Tom, have you tried the Grainger Catalog?

I originally meant that jokingly, but in light of your last post, I think that is where your answer lies.

rp

I can usually understand what people are trying to explain, but I tend to have the opposite problem. People ask me a yes/no question and sometimes I have to say no because of the terminology.

"Was your suitcase in the trunk of the cab?"

No. It IS in the trunk of the cab, that just drove off. I can still see the cab, and it hasn't jumped out by itself, so it is still in there.

I think specific langunage and engineering go hand in hand, it is all about thought process.

Reminds me of that old line:

"Have you stopped kicking your dog yet?"

Somehow a yes or no answer doesn't quite fit.

DOL

Originally it was a discussion on Linkedin about big band saws in saw mills and the meaning of “stress” and “strain”. These are actually complex tools in spite of being essentially a single piece of steel.

The group was following the excellent advice above and was working its way toward an understanding of terms used.

Then someone posted, identifying themselves as an engineer with decades of engineering and design experience. His post was to the effect that he was an expert and that no one in the discussion knew what they were talking about because they were misusing all the terms.

So I got wondering if there really is a definitive source.

Thomas J. Walz
Carbide Processors, Inc.
www.carbideprocessors.com

Good engineering starts with a Grainger Catalog.

Seems to me that if the usage of stress and strain contradicts that of "Roark's Formulas for Stress and Strain" then it's wrong. So, perhaps, one should refer to Chapter 1 in Roark's for his definitions.

TTFN
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IRstuff,

Chapter 2 in my copy of Roark's.

Once the terms stress and strain are defined in a mechanics of materials book, all sorts of fancy math takes place. If someone has a different definition of stress and strain to the point of affecting all that math, then we all are in trouble.

--
JHG

I've got a pretty old partial copy from Mathsoft, dated 1992

TTFN
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Tom,

First, I don't remember any sawmill floors where people could actually talk to each other - too high of a noise level.

Second, not to denegrate sawmill folks (my maternal grandfather was a sawyer and after I found out what that meant in the sawmill world, I lamented that he had already passed and we couldn't discuss it) but most sawmill folks I ever worked with couldn't understand engineering terminology even if there was a book of definitions that could be handed to them. Not that they didn't have some good ideas and a good grasp of what the problem was, but some concepts just didn't get through and all the explaining in the world wouldn't convince them (try to describe why a centrifugal pump's output pressure decreases as the flow increases...).

You have to laud them when they have a good idea, even if they butchered engineering terminology in describing it and on other occasions just agree to disagree when their idea is way off base due to their not being confused by the facts we learned while getting an engineering education.

rmw

rmw

I do not agree, but hey that's what makes the world go round.
I believe it is possible once management is on track.

Continuous Improvement & it would be class , student type of environment.
let me ask if there is any one here that knows it all. :>)
we either Jack of all trades or specialized. yes & no?

Mfgenggear