Newsgroup sci.engr.mech 28436

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I am working on a fracture mechanics problem for my MS thesis using
ALGOR FEA software.  My model is too big for my PC and keeps crashing. 
Are there any ALGOR users out there that have the capability to run a
model with approximately 120,000 degrees of freedom on the APAK0H
(non-linear stress analysis) processor?  If so, would you be willing to
run my model for me.  I am a lowly graduate student, so I am hoping
someone will do this as a charity case.
-- 
Ed Haack, P.E.		
edhaack@sprynet.com
704-382-0811, 704-382-3797 fax

DC wrote:
> 
> Why doesn't a person electrocute himself when he turns on the
> ignition in a car, since he is holding a metal key contacting metal
> leads (to the battery) in the steering column, and moreover his body
> is touching the car's ground (its frame)?
> Thanks for clarifying this.
> 
> --
> From 75277.3335 at CompuServe
I ALWAYS wear rubber gloves when driving the car to prevent this.
JT
********************************************
      Jeff Thorssell/Baltimore
http://204.255.212.10/~jthorsse/eectest.html

>Gary Lynn Kerr said...To whom ever wrote that the term 
draftsMEN was not correct.  GET A LIFE!   
>And a female boss has a problem with it she has too much time 
on her hands....GET A LIFE! ....snip, snip, snip!
Here, here Katarina!  
Gary, it's rather sad you feel the way you do, maybe you'll get 
a life yourself one day.  In the meantime, will you take that 
attitude with your female boss when she has to reprimand you?  
(If you don't have a female boss yet, chances are you'll 
probably have one in the future).  Get rid of your appalling 
attitude before she gets rid of you!
______________________________________________________________
Jane Watson                     |           
Mechanical Engineer             | Views expressed here
Radar Systems Division          |  are entirely my own...
GEC-Marconi Avionics            |
______________________________________________________________

> But that is not the real issue, and that's what
>I wanted to talk about in the first place.  The real issue is that nobody
>seems to want to *try* the simple solution first.  What I want to know is
why
>that is? 
>
>Best Regards, Jon Priluck 
This was the case with the company I previously worked with.  We would sit
around in a design review meeting and think up problems that might
possibly occur.  Someone would come up with something that might happen,
and we would design around it.  Doesn't matter if the problem is real or
not, we gotta design this thing so that nothing could possibly go wrong. 
We would soon end up with a complicated mess that had no chance of
working.  I got the hell out of that company.
Sounds like you are in a similar position.  Also sounds like you are too
low on the ladder to really be heard, the guys above you are making the
decisions.  Well, you can leave.  Or you can be patient, stick it out, let
them do it their way, then maybe someday you will be near the top of the
ladder and can do it your way - start simple and make it more complex as
needed to solve problems that arise.
I wish you the best of luck,
Kevin

Alan Phang wrote:
> A tiny silver-plated conical cup in which sits a light-emitting semiconducting
> die is to be filled with a liquid chemical (which will blend well with epoxy)
> such that no air voids or bubbles are present in the cup.
> 
> As 300 of such cups need to be simultaneously filled, the most convenient way
> (or so it seems) is to VERTICALLY immerse the cups into a solution bath as
> shown below.
Do the cups have to be filled in batches, or would a rapid succesion be 
adequate? To prevent air being trapped, the cups would need to be
inserted 
into the solution at an angle less than the angle of the cup cone...
              / (<44 deg)
             /  
        ----/
  (>45deg) *| cup
            |
      ============== solution        
If it is possible for the leads, and the entire supporting mechanism to
be 
immersed, then the batch of cups could be inserted at the required
angle. 
As this seems improbable, a continuous rotating mechanism may be
applicable.
             -| |- cups
             -|.|- 
       _______/|\_________
                       solution
regards
--
Horst Weinert                          weinert@mech.und.ac.za
Manufacturing & Mechatronics           tel. +27 (0)31 260 1227
Dept. of Mechanical Engineering        fax. +27 (0)31 260 3217
University of Natal, South Africa
-- ------ --

Mike Mitchell wrote:
> 
> Paul Skoczylas wrote:
> 
> > > While I can't think of a case in which a software error caused a
> > >  fatality let me assure you it is quite possible.
> >
> > I think the point being made is that it's not the software that is
> > reponsible, but the person who designed the software.
> >
> > -Paul
> 
> Oh yes indeed software has killed.  One example that sticks in my mind
> was a cancer x-ray treatment machine that had a bug to allow an x-ray
> technician to accidently set a dosage way above the limit.  The patient
> died a horrible and painful death.  It nothing to do with PE licenses
> either - the FDA software validation was fudged somewhere along the way.
>
The software didn't write or validate itself.  The people who wrote the
code and/or did the validation and error checking obviously missed
something.  It seems to me that it's like saying when a building
collapses, the building killed people, rather than the people who
designed/constructed the building killed people. 
-Paul

Jon Peltier wrote:
> 
> In article <55qaug$i5k@lore.sprynet.com>, koalmnr@m2.sprynet.com (M. C. (Mike) Albrecht) says:
> >
> >In article <327F82EA.32E4@mmm.com>, dfroell@mmm.com says...
> >>
> >>I am looking for a technique to quickly and easily identify hairline
> >>fractures and cracks in large steel and chrome cylinders.  The
> >>cylinders are stored on racks and weigh well over 500 lbs each.
> >>I would like to inspect them while they are stored on the racks.
> >>Can anyone help
> >
> >The simplest method is to use dye penetration method.  Were a colored
> >dye, uusally blue is sprayed on the metal, excess wiped off and the
> >surface checked for cracks.  Some dyes respond to ultraviolet light
> >making them more visible.
> >
> >A more time consuming method is to use a magnetic based fluid and
> >then scan for it.
> 
> A third technique would be an eddy current testing apparatus, but
> geometric constraints, the amount of surface to scan, and the ability
> to reach everywhere with the probe would limit its usefulness.  If you
> knew how & why the cracks formed, it would focus your search.
> 
> |----------------------------------------|
> |  Jon Peltier       Research Scientist  |
> |  AlliedSignal Research and Technology  |
> |  Morristown, NJ          201-455-2373  |
> |  Jon.Peltier@AlliedSignal.com          |
> |----------------------------------------|
The SIMPLEST method is also the cheapest and fastest, tap it with a
hammer, ALL simple castings will ring, used to check railway carriage
wheels this way. After a week or so you will develop an "ear" for it and
be 100% accurate, also detecting porosity and thinwalling.
Sorry, you don't have to send me $10,000 for a dumb product you don't
need.
later
JB

Dr. R.D. Kane wrote:
> 
> InterCorr/96 - The First Global Internet Corrosion Conference. This is
> the first corrosion conference where technical papers are
> presented, published and archived on the Internet. InterCorr/96 is
> pleased to announce the posting of the first technical society session
> sponsored by ASTM entitled, "Corrosion Tests and Standards: Application
> and Interpretation".
> 
> These papers will be posted over the period June through February, 1997.
> This innovative format provides for unlimited global access of the
> papers from the InterCorr/96 Web Site:
> 
> http://www.clihouston.com
> 
> There have been over 730 registrants from over 30 countries worldwide.
> Registration is complimentary provided by the corporate sponsors
> participating in the first Internet Virtual Tradeshow also found on the
> InterCorr/96 Web Site.
> 
> Dr. R.D. Kane
> 
> --
> CLI International, Inc.
> The Materials & Corrosion Specialists
> http://www.clihouston.com
> 
> CLI's New Specialty Equipment Division offers
> Equipment backed by service and experience.
Bit pretentious postic with a title, we can all do it mate, but some of
us aren't peacocks, we are REAL engineers.
later
JB

Max Edelhauser wrote:
> 
> Does anyone know of a manufacturer of a complete off-the-shelf assembly
> for Solar Panel + Mounting Post + Battery Charger + Battery  solution,
> like the road emergency celular phone sites along the highways?
> 
> Please let me know if you do. I would prefere an e-mail response, but a
> news group response is OK too.
> 
> - Max
I know of exactly the company you need.  They did some really nice work
for me last year.  Call, write, fax or e-mail:
Direct Power & Water Corp.
3455-A Princeton NE
Albuquerque, NM 87107
505-889-3585 Tel
505-889-3548 Fax
Email: dirpowdd@directpower.com
Talk to Jeff Randall or to Kevin Goodreau.
When I was at their shop a few months ago, they were building a lot of
cell-phone power systems (on poles) for a company that was setting up a
cell network in Indonesia.
Best wishes, I hope they can help.
-- 
M.E. Moore
Los Alamos, NM

I just drove down the New Jersey Turnpike. The toll collectors are enrolled
in an organization called "Brotherhood of Professional Engineers". I hope
they are not the ones designing the turnpike's bridges.

Computer Graphics 
Full ot Part Time
486/Pentium PC or better Required
Will Pay Average $30/hour
Contractors Welcome
800/455-3558 inside U.S
818/865-6940 outside U.S

Check out a quality Web site that matches the quality of our
manufacturing services:
http://www.reliancetool.com

The Silicon Surfer wrote:
> 
> Jon Peltier wrote:
> >
> > In article <55qaug$i5k@lore.sprynet.com>, koalmnr@m2.sprynet.com (M. C. (Mike) Albrecht) says:
> > >
> > >In article <327F82EA.32E4@mmm.com>, dfroell@mmm.com says...
> > >>
> > >>I am looking for a technique to quickly and easily identify hairline
> > >>fractures and cracks in large steel and chrome cylinders. 
snip
> 
> The SIMPLEST method is also the cheapest and fastest, tap it with a
> hammer, ALL simple castings will ring, used to check railway carriage
> wheels this way. After a week or so you will develop an "ear" for it and
> be 100% accurate, also detecting porosity and thinwalling.
> 
> Sorry, you don't have to send me $10,000 for a dumb product you don't
> need.
> 
> later
> 
> JB
I spoke to a guy at Newcastle University (UK) two years ago who
described 
using resonance techniques, but with some computerized spectrum
recognition for pressure cylinders. Up to you whether you follow up
or not ...
Cheers
Ian Pain

dano@cyberramp.net wrote:
> 
 writes:
> >It seems to me that it's like saying when a building
> >collapses, the building killed people, rather than the people who
> >designed/constructed the building killed people.
> 
> Well, buildings don't design themselves, either.
> 
That's my point.  We blame the engineer or builder for the building, so
why would we blame the software instead of the programmer?
-Paul

In <3288918F.5DDB@cfer.ualberta.ca>, Paul Skoczylas  writes:
>Mike Mitchell wrote:
>> Oh yes indeed software has killed.  One example that sticks in my mind
>> was a cancer x-ray treatment machine that had a bug to allow an x-ray
>> technician to accidently set a dosage way above the limit.  The patient
>> died a horrible and painful death.  It nothing to do with PE licenses
>> either - the FDA software validation was fudged somewhere along the way.
>>
>The software didn't write or validate itself.  The people who wrote the
>code and/or did the validation and error checking obviously missed
>something.  It seems to me that it's like saying when a building
>collapses, the building killed people, rather than the people who
>designed/constructed the building killed people. 
Well, buildings don't design themselves, either.
>-Paul
      program signature
      write(*,*),'Dan Stephenson'
      write(*,*),'dano@cyberramp.net'
      stop
      end

> 
> In that case how about a motorbike 2-stroke?
> 
> --
> Dave Howell
Dave,
The problem with bike engines are that most have the gearbox intergral
with the engine and therfor the power to weight of them is not that
great.  The exception is the BMW's K and R series.  However the $2000 tag
feels a bit much at the moment for a second hand bimmer engine.  cf $600 -
800 for a car engine.
Bill

>Aside, dont you think the egg drop thing has been done
>enough?  Do our science teachers have no creativity?
      We haven't had an egg drop here at West Virginia University for about a 
decade.  The solution is too simple - one egg, one or more foam cartons the 
eggs come in.
      Our ASME students run a PUMPKIN drop.   Fifteen (or more) pounds of 
pumpkin falling ten stories - more exciting than a little egg in a paper box.  
Failure rates of about 50%, not 5%.

	This egg-drop mechanism has been suggested as a design problem
	in ASME design competition; however I forget if that was this 
	year though.
        Is it fair to have advantage in this competition by taking help
	from professionals?
							snehasis
--
India-monsoon and marigold, dung and dust, colors and corpses ,
smoke and ash, snow and endless myth- is a cruel, unrelenting
place of ineffable sweetness. It is the most difficult and most 
rewarding of places to travel.
-James O'Reilly

For Sale: Coal Crusher, Pennsylvania Crusher Type K; Single Roll; Size
30 X 72A; Feed Size 30" max.; 125 Tons/Hr. Capacity.  This unit is used
but in good condition.  New spare parts for the unit are available. 
For more information, contact Rick Davis (812) 866-4934, fax (812) 866-
5022) or respond via e-mail.

Gary Lynn Kerr wrote:
> 
> To whom ever wrote that the term draftsMEN was not correct.  GET A LIFE!
> When the word men/man is used in a word it is generic and means mankind.
> And a female boss has a problem with it she has too much time on her
> hands.  Also that same feMALE boss probably would not liked being
> referred to as feMALE/woMEN.  As I said before GET A LIFE!
> 
> On Sat, 9 Nov
> 1996, Jim Weir wrote:
> 
> > Peter  shared these priceless pearls of wisdom:
> >
> > ->ATTENTION ALL ENGINEERS AND DRAFTSMEN:
> >
> > I'd suggest before you get out into the real world with a female boss that
> > you find another word for "draftsMEN".
> > >
!!!!!! AMEN !!!!!!!
People who try to change a language to suit their views should study the
lexicon of it first. Words do not mean what we want, they mean what are.
-- 
No Electrons Were Harmed In The Production of This Article.
RGZ
             http://homepage.interaccess.com/~rgzinn
               <------------ C.A.V.I.------------>                
               |= Goldsmith Yamasaki Specht Inc.=|               
               |=  900 N. Franklin st. ste. 510 =|               
               |=    Chicago, IL. 60610-2134    =|               
               |=  GooD DesigN is GooD BusinesS =|
               |=       Ph.  312-266-8404       =|
               |=       Fax. 312-266-2315       =|
               <--------------------------------->
Respectfully
Raymond G. Zinn
rgzinn@interaccess.com
November 12, 1996
1:39 pm

José Emiliano de Llano wrote:
> 
> Primero saludaos a todos los que veais este mensaje, soy un novato en esto
> de las comunicaciones, es mi primer día de News. Ya me pasaré por aquí más
> a menudo.
> Oscar, que alegría un tío que habla castellano por aquí. Soy compañero del
> gremio de la construcción, soy Ingeniero Técnico de Obras Públicas, de
> Madrid. Trabajo en una constructora.
> Según me parece entender en tu mensaje habeis creado una página WEB en la
> Escuela de Caminos ya me pasaré por allí, seguro que es interesante.
> Bueno espero que sigamos en contacto, eres mi primer contacto en esto de
> las news.
> Hasta otro rato.Hola jose, tambien nuevo en esto. me dedico a la mecanica de suelos y 
estoy en gerona. nos volveremos a comunicar, hasta otra.

Javier wrote:
> 
> On 30 Oct 1996 18:52:53 GMT, "José Emiliano de Llano"
>  wrote:
> 
> >
> >Primero saludaos a todos los que veais este mensaje, soy un novato en esto
> >de las comunicaciones, es mi primer día de News. Ya me pasaré por aquí más
> >a menudo.
> >Oscar, que alegría un tío que habla castellano por aquí. Soy compañero del
> >gremio de la construcción, soy Ingeniero Técnico de Obras Públicas, de
> >Madrid. Trabajo en una constructora.
> >Según me parece entender en tu mensaje habeis creado una página WEB en la
> >Escuela de Caminos ya me pasaré por allí, seguro que es interesante.
> >Bueno espero que sigamos en contacto, eres mi primer contacto en esto de
> >las news.
> >Hasta otro rato.
> >
> Hola José Emiliano, coincido contigo en casi todo, soy novato en las
> News, soy ITOP, y estoy en Burgos.
> Nos volveremos a comunicar. hasta pronto.
> Saludos:
Hola Javier, trabajo en mecánica de suelos en Gerona, o mejor dicho, 
vivo en gerona pero trabajo por toda espana. Hasta otra.

>Thhe oficial point where voltage is considered dangerous is 78 volts....
>..voltage above 78 volts is cnsiderd high voltage and below its not
>some product are often labled with Max. Occ. voltage 78 volts.
>The Direct current is actually much worse to get shocked by in high voltage
>then Alternating current.
>Yeggster
Well, lets not forget that it is the amperage that kills you,  no the
voltage.  I can place my hand on a Vand der Graff generator that is
producing in excess of 10,000 V and not be harmed.  However, it is
only producing a fraction of a mA.  It only takes a few amps to stop
your heart.
------------------------------------------------
Sean Dotson           --Mercury Productions Inc.
sdotson@mpinc.com	    --Digital Design and
http://www.mpinc.com		  --Distribution
------------------------------------------------

C. Southern (southc@hiwaay.net) wrote:
: What's a good pre/post processor for use with Cosmic NASTRAN? I will
: be generating my models with AutoCAD. Any suggestions?
I would recommend hypermesh.  A PC version is available.  check out
www.altair.com

Please check out http://www.tetraprec.com/tetra if you are interested
in machine tool accuracy, and a revolutionary new instrument to
measure it.  Tetra Precision offers both sales and service to meet
your high precision machine tool calibration needs.

>  I am looking for a RUbber Diaphragms suppliers
> for valves industries.
Restraint... I must show restraint... no  won't say it.

Jane, Watson wrote:
> 
> >Gary Lynn Kerr said...To whom ever wrote that the term
> draftsMEN was not correct.  GET A LIFE!
> >And a female boss has a problem with it she has too much time
> on her hands....GET A LIFE! ....snip, snip, snip!
> 
> Here, here Katarina!
> 
> Gary, it's rather sad you feel the way you do, maybe you'll get
> a life yourself one day.  In the meantime, will you take that
> attitude with your female boss when she has to reprimand you?
> (If you don't have a female boss yet, chances are you'll
> probably have one in the future).  Get rid of your appalling
> attitude before she gets rid of you!
I have a female boss already,  and she is open enough to realize that when I say 
draftsman or designer,   I mean the same thing.  She calls them the same...  Why 
does everything have to be so "politically correct".  Why would you be offended 
to be called a draftsman if that is what you have studied to be?  What would you 
rather be called?  A draftswoman?  Geeez....    I agree with Gary,  get a life! 
IM(not so)HO!!!
-- 
Andy Kidd   kidd@inetdirect.net   http://netdirect.net/~kidd
"He who knows not, and knows not that he knows not, is a fool. Shun him.
He who knows not, and knows that he knows not, is a child. Teach him.
He who knows, and knows not that he knows, is asleep. Wake him.
He who knows, and knows that he knows, is wise. Follow him."---Author unkown

Is anybody here to help me to increase the efficiency
of a water ram?
I suppose the efficiency in pumping water is only a few
percentage.Before I start to measure it I want find out
the possibility of increasing it.
Thanks in advance,Martin

In article ,  writes:
> Path: 
actcom!news.new-york.net!news.wctc.net!feeder.chicago.cic.net!chi-news.cic.net!ddsw1!news
mcs.net!www.nntp.primenet.com!nntp.primenet.com!feed1.news.erols.com!howland.erols.net!n
ewsfeed.internetmci.com!in1.uu.net!ott.istar!istar.net!news.nstn.ca!coranto.ucs.mun.ca!sl
ip2.engr.mun.ca!andy
> From: andy@engr.mun.ca (Andy Harbin)
> Newsgroups: sci.engr.mech
> Subject: Aluminum finned tubing
> Date: Fri, 8 Nov 1996 00:47:57
> Organization: Memorial University
> Lines: 18
> Message-ID: 
> NNTP-Posting-Host: slip2.engr.mun.ca
> X-Newsreader: Trumpet for Windows [Version 1.0 Rev A]
> 
> I'm looking for a supplier of high grade (ie 6061-T6 if possible) finned 
> tubing for a liquid to air heat exchanger for a custom application.  Design 
> criteria are high efficiency, high strength and light weight - hence the high 
> grade required.   If anyone knows of a supplier of such could you please put 
> me in contact with them.  
> 
> Otherwise I'd like to know what is the grade of the 
> aluminum used in standard aluminum tubing and its material properties (ie 
> tensile stregnth, burst pressure of say of 3/8" OD with 0.049" wall).
> 
> I can provide more information to those that wish it.
> 
> Thank's for the help.
> 
> Andy Harbin
> Senior Mechanical Engineering Student
> Centre for Cold Ocean Resources Engineering (C-CORE)
> Memorial University of Newfoundland, CANADA
> 
You should try either Lytron at Woburn,MA and/or LIMCO at Long Island,NY.
Lytron`s are inner fins in welded tubes (high pressure), while LIMCO is the 
usual plate & fins (brazed) type.
Lytron/Tom Mathers (617) 933 7300
Hope you found the above helpfull.
Avi :)

Hello all!
We need an induction furnace, and we need it fast (within the next month
or two--if this sounds slow, you don't know the induction furnace
industry!).  We are looking for a 35-60 kW, 10-30 kHz power supply, and a
furnace designed for melting 20-50 lbs of metal.
We would be interested in talking to anyone with a used furnace to sell.
Please send me e-mail at:
asudhal@trinova.com, or
atuls@umich.edu
or call me at
313-741-5318
or fax me at
313-741-5333
or write to me at:
Atul Sudhalkar
Aeroquip Corporation
2323 Green Road
Ann Arbor, MI 48105
I'll check this newsgroup for the next few days, but would prefer one of
the above means of communication!
Thanks!
Atul

In article <32867158.5C10@infinet.com>, mwcraig  wrote:
>thad kimo wrote:
>> 
>> i am writing a term paper for my material science engineering class and
>> need information (books, articles, & websites)on precipitation-hardened
>> stainless steels which protect flight deck recorders from various
>> elements.  i need to know its durability, how it is tempered, & what
>> other possible alternatives are for these recorders.  submission of
>> references would be greatly appreciated.
>Try the American Society for Testing and Materials (ASTM). I know of one spec 
>for precipitation-hardened stanless steel is ASTM A747 (just like the plane) 
>but I think this spec is for castings.  You are probably interested in sheet 
>or plate.  Look in the ASTM index.  Another place to look is the Ameican 
>Society of Metals (ASM) "Metals Handbook". 
ASTM A564   Standard Specification for Hot-Rolled and Cold-Finished
Age-Hardening Stainless Steel Bars and Shapes
ASTM A693   Standard Specification for Hot-Rolled and Cold-Finished
Age-Hardening Stainless Steel Plate, Sheet, Strip
ASTM A705   Standard Specification for  Age-Hardening Stainless Steel Forgings
there's a lot more plus an SAE AMS spec for each alloy, ex:
AMS 5629 PH13-8 Mo   bars, shapes, forgings (VIM + CEVM)
AMS 5864 PH13-8Mo Plate [VIM+CECM]  solution treated
etc.
Harry
A professional is a person who can do his best at a time when he doesn't 
particularly feel like it. -Alistair Cooke

Jeff Thorssell wrote:
> 
> DC wrote:
> >
> > Why doesn't a person electrocute himself when he turns on the
> > ignition in a car, since he is holding a metal key contacting metal
> > leads (to the battery) in the steering column, and moreover his body
> > is touching the car's ground (its frame)?
> > Thanks for clarifying this.
> >
> > --
> > From 75277.3335 at CompuServe
> 
> I ALWAYS wear rubber gloves when driving the car to prevent this.
> 
> JT
> 
> ********************************************
>       Jeff Thorssell/Baltimore
> http://204.255.212.10/~jthorsse/eectest.html
Not me - I get someone else to start it for me.

We're looking for a Mech E to start 1/1/97 in our Imaging Division. Please
email or fax me your resume at (408)247-3875
Job Description:
Senior Mechanical Engineer to support color ink jet printer product
development. Background in one or more of the following areas required:
Mechanical design emphasizing dynamics and mechanism design, print head/ink
systems, color science. Will serve as mechanical lead for entry-level color
ink jet printer development from investigation phase through to production.
Responsibilities will include conducting technology investigations and
competitive analysis, developing test plans for evaluating print quality
and printer engine performance, working closely with product design,
product test, product safety and other support groups. Experience working
with OEM vendors is a plus. Requires BSME (MSEE preferred) plus 5 years of
relative experience. Imaging Science graduates with a mechanical background
will also be considered.

In article , andy@engr.mun.ca (Andy Harbin) wrote:
>I'm looking for a supplier of high grade (ie 6061-T6 if possible) finned 
>tubing for a liquid to air heat exchanger for a custom application.  Design 
>criteria are high efficiency, high strength and light weight - hence the high 
>grade required.   If anyone knows of a supplier of such could you please put 
>me in contact with them.  
>
>Otherwise I'd like to know what is the grade of the 
>aluminum used in standard aluminum tubing and its material properties (ie 
>tensile stregnth, burst pressure of say of 3/8" OD with 0.049" wall).
Look in ASTM B404. Standard Specification for Aluminum and Aluminum-Alloy
Seamless Condenser and Heat-Exchanger Tubes with Integral Fins
alloys covered 1060, 3003, Alclad 3003, 5052, 5454, 6061.
A professional is a person who can do his best at a time when he doesn't 
particularly feel like it. -Alistair Cooke

bikerbabe in black leather wrote:
> 
> In article <5665u7$3pu@Nntp1.mcs.net>, Tommy E.   wrote:
> >
> >>From: DC, 75277.3335@CompuServe.COM
> >
> >>>What completes the grounding circuit in an electrical system?
> >>Let's say a refrigerator shorts and the current goes to ground (thus
> >>protecting anyone touching the refrigerator).
> >>The current goes through a wire down to metal pipe down to the earth
> >>itself, but how does it come back from the soil in the back or front
> >>yard to complete the circuit to the refrigerator in the house?
> >>Thanks for help and info.
> 
> To clear up a bit of a misnomer, ground has several meanings.  In
> general it's used to indicate something that is at zero volts with
> respect to a source.  The earth ground is used mainly for protection
> from lightening or similarly induced voltages, and is used to ensure
> that all wires into a  house are at the same ground voltage with
> respect to each other.  This includes phone lines and cable.(snip)
For power, ground is a reference. At the main breaker box, the typical 
single phase residential power line has a pair of wires at 240VAC and a 
center tap that will give you 120 from it to either of the other two 
wires.  At the main box this center tap is connected to ground and 
becomes the zero voltage reference and the return path for neutral.  
Ground and neutral are the same thing at the main box - and ONLY at the 
main box because there is power running thru the neutral wires and none 
thru thru the ground, (normally), and the resistive drop will cause a 
slight voltage difference between the two at an outlet that is carrying 
a load there or from others along that circuit from the main.  
So to your question, the power from a faulty hot lead goes to ground if 
the refrigerator is grounded. It completes the circuit back to the main 
box where ground is connected to the center tap where it flows back to 
the transformer. -- it does NOT flow down a pipe into the earth any 
significant amount. If the bad connection conducts enough current the 
main breaker will trip.   If the refrigerator is not grounded it becomes 
a real hazard in a kitchen where there are many places to touch a 
good ground connection such as the sink or other grounded electrical 
appliances. 
It is important to verify that ground circuits are not open anywhere from 
the outlet on back to the main box.  An open ground at the main will let 
a fault from any single '3 prong plug' appliance anywhere in the house 
present a shock hazard to ALL the other supposedly 'grounded' appliances 
in the house connected by their 3 prong plugs to that 'live ground'.  
This is extremely dangerous especially in bathrooms with wet people and 
portable electric heaters, etc.  
The practice 30 years ago, (when '3 prong' 120VAC plugs were very rare), 
many states allowed the ground wire to be wrapped around the romex 
sheathing and clamped in a non-conductive strain relief to connect to the 
enclosure via the clamp.  In time, the clamp nuts loosen, the box 
corrodes resulting in a poor ground path.  Many do-it-yourself types 
blindly trust that the outlet box is ground when there really isn't one 
there.  Always check it.  I unwrap the ground wire and connect it to the 
box and the outlet and do it at each box all the way back including the 
main. (Be sure that any wire isn't close to fatigue failure.)
GFI circuits check that the amount of current that flows thru the hot 
side is no greater than that flowing thru neutral.  Any difference means 
the power is flowing somewhere else to ground and the circuit is then 
electronically interrupted.  The allowable difference is sensed in the 
range of micro-amps I believe..(?)  It only takes a very small amount of 
electrical current through the heart to cause fibulation in some people. 
Mike (Intended for reference not practical application)

Sunduck Kim  wrote
> Are there any online education by internet?
> I want to know the information about online education of mechanical
engineering.
	If it is about continuing education, my local newspaper this morning
happens to carry an article from the New York Times listing many Website
addresses of colleges or universities offering online continuing education
classes.   But unfortunately none of the listed classes concerns
engineering.  There are some on computer science, natural science, and
social science.  After all, mechanical engineering education involves
laboratory experiments and design classes and projects.
	John Cheung, PhD, Singapore 

On 12 Nov 1996, it was written:
> 
> >Gary Lynn Kerr said...To whom ever wrote that the term 
> draftsMEN was not correct.  GET A LIFE!   
> >And a female boss has a problem with it she has too much time 
> on her hands....GET A LIFE! ....snip, snip, snip!
>  
> Here, here Katarina!  
> 
> Gary, it's rather sad you feel the way you do, maybe you'll get 
> a life yourself one day.  In the meantime, will you take that 
> attitude with your female boss when she has to reprimand you?  
> (If you don't have a female boss yet, chances are you'll 
> probably have one in the future).  Get rid of your appalling 
> attitude before she gets rid of you!
>
> Jane Watson                                
> Mechanical Engineer                            
> 
Jane,
	I have worked for several women and I'm sure that I will work for
and with many more.  The terms salesman, draftsman, mailman, ...  have
been in use for more years than we have been around.  Everyone was OK with
these terms until a feminist decided that they were degrading to women.
Since the terms are GENERIC I do not see how this can be the case.  Where
do we stop???  Do we change mankind to humankind?  That doesn't work
either because human contains "man" also.  How about personkind?  Do we
also change woman to womyn??  People should be able to use the term of
their choice without the fear of retribution form the oppossing camp.  I
feel that Katrina was out-of-line when she wrote her comment about the
survey.  I also feel that any boss that that takes offense to the original
terms has too much time on their hands.  I have asked several female
friends and co-workers about this topic and they all agree with my point
of view.  On a related topic, using the term he/she is even worse.  Choose
one or the other or use a generic term.  Enough for today.
Gary

I am looking for free software about finned excchangers
calculation,possibly with source file.
Andrea Lucchetti
Rome.

Paul Skoczylas wrote:
> 
> Walter Driedger wrote:
> >
> > >On Thu, 24 Oct 1996 07:32:44 -0400, Yan Seiner, PE (cardinal@hargray.com)
> > >said...
> > >>
> > >>Software to my knowledge has never been the direct cause of a fatality.
> > >>If ever there was a fatality due to software failure, it ws because
> > >>someone did not take the time to learn about the limitations of the
> > >>software and maybe did not perform a sanity check on the results.
> > >>
> > >>In other words, the person who built the system should have insured that
> > >>the software results are correct; or in the case of a control system,
> > >>built the system so that mechanical limitations come into play before
> > >>anyone is injured.
> > >>
> >
> > While I can't think of a case in which a software error caused a
> >  fatality let me assure you it is quite possible.
> 
> I think the point being made is that it's not the software that is
> reponsible, but the person who designed the software.
> 
> -Paul
This same point can be made for a hardware failure that leads to a 
fatality.  Either the designer failed to account for how the hardware 
can fail (mechanical or electrical failure conditions and wear) or did 
not account for the interaction with other system components (effect of 
part A failing causes part F to fail).  A person is always ultimately 
responsible.
BTW if you are interested in cases where software is "blamed" for 
failures resulting in damage or death - look at the ACM Software 
Engineering Notes.  Also the book SAFEWARE by Nancy Leveson documents 
several cases such as the Therac-25 where software replaced hardware 
(mechanical) interlocks and killed several people.  The software 
designer disappeared.
This does not make a case for licensing, but does call for better 
regulations on life-critical systems.  The aviation field does the best 
job of this.  Medical and other transportation systems need to catch up.
Jim Chelini

Sounds like a contest I once had in school.  The winner (not me)used a
round hard foam ball that was hollowed out.  On the inside, he suspended
the egg on rubber bands from multiple directions.  The result was a
shell, that no matter how it landed, kept the egg from impacting the
side of the case due to the elasticity of the rubber bands.  
Using steel casing or water on the inside adds to the mass and the
impact.  Keep it light and use "springs' to solve your problem.
As far the critisms for asking for help....Advise is free.  Making it
work is engineering........
					Good luck,
						James S.