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chapterWhat The Establishment's Scientists Say
smartquoteWhat a textbfChutzpah? to say samething like that!
In this section exhibits the establishment ``experts'' reaction
the position that the ``common'' pQtwo diagram is improper.
Their comments are responses to the author's paper: ``The mathematical theory of
the pQtwo diagram'' (similar to Chapter refchap:pQtwo)footnoteThe
exact paper can be obtain free of charge from
Minnesota Suppercomputing Institute, http://www2.msi.umn.edu/publications.html
report number 99/40 ``The mathematical theory of the pQtwo diagram''
or by writing to the Supercomputing Institute, University of Minnesota,
1200 Washington Avenue South, Minneapolis, MN 55415-1227.
The paper was submitted to Journal of Manufacturing Science and Engineering.par
This part is for the Associate Technical Editor Dr. R. E. Smelser.
textbfI am sure that you are proud of the referees that you have chosen and
that you do not have any objection whatsoever with publishing this
information. Please send a copy of this appendix to the referees. I will
be glad to hear from them.
This concludes comments to the Editor.par
I believe that you, the reader should judge if the mathematical theory
of the pQtwo diagram is correct or whether the ``experts''
position is reasonable.
For the reader unfamiliar with the journal review process,
the associate editor sent the paper to ``readers'' (referees) which are anonymous
to the authors.
They comment on the paper and according to these experts the paper acceptance
I have chosen the unusual step to publish their comments because I believe
that other motivations are involved in their responses.
Coupled with the response to the publication of a summary of this paper in the Die
Casting Engineer, bring me to think that the best way to remove the information
blockage is to open it to the public.
Here, the referees
can react to this rebuttal and stay anonymous via correspondence
with the associated editor.
If the referee/s choose to respond to the rebuttal,
their comments will appear in the future additions.
I will help them as much as I can to show their opinions.
I am sure that they are proud of their criticism and are standing behind it 100%.
Furthermore, I am absolutely, positively sure that they are so proud
of their criticism they glad that it appears in publication such as this book.
sectionSummary of Referee positions
The critics attack the article in three different ways.
All the referees try to deny publication based on grammar!!
The first referee didn't show any English mistakes
(though he alleged that he did).
The second referee had some hand written notes on the preprint
(two different hand writing?)
but it is not the grammar but the content of the article
(the fact that the ``common'' pQtwo diagram is wrong) is the problem.
Here is an original segment from the submitted paper:
fboxparboxpagewidthboxThe design process is considered an art for
the 8-billion-dollar die casting industry.
The pQtwo diagram is the most common calculation, if any that all, are used
by most die casting engineers.
The importance of this diagram can be demonstrated by the fact that
tens of millions of dollars have been invested
by NADCA, NSF, and other major institutes
here and abroad in pQtwo diagram research.par
In order to correct ``grammar'', the referee change to:
doubleboxparboxpagewidthboxThe pQtwo diagram is the most common
calculation used by die casting engineers
to determine the relationship between the die casting machine and gating design
parameters, and the resulting metal flow rate.
It seems, the referee would not like some facts to be written/known.
textbfSummary of the referees positions:
Well, the paper was published before (NADCA die casting engineer) and the errors
in the ``common'' pQtwo are only in extreme cases.
Furthermore, it actually supports the ``common'' model.
Very angrily!! How dare the authors say that the ``common'' model is wrong.
When in fact, according to him, it is very useful.
The bizzarro approach!
Changed the meaning of what the authors wrote (see the ``ovaled boxed'' comment
This produced a new type logic which is almost absurd.
Namely, the discharge coefficient, cd, is constant for a runner or
can only vary with time.
The third possibility, which is the topic of the
paper, the fact that cd cannot be assigned
a runner system but have to calculated for every set of runner and die casting
machine can not exist possibility,
and therefore the whole paper is irrelevant.
Genick Bar-Meir's answer:
shadowboxparboxpagewidthboxLargetextrmtextbfLet me say what a smart man once said before:
I don't need 2000 scientists to tell me that I am wrong.
What I need is one scientist to show what is wrong in my theory.
Please read my rebuttal to the points the referees made.
The referees version are kept as close as possible to the original.
I put some corrections in a square bracket  to clarify the referees point.par
refereetextbfReferee comments appear in roman font like this sentence,
rebuttaland rebuttals appear in a courier font as this sentence.
sectionReferee 1 (from hand written notes)
refereeSome awkward grammar - See highlighted portions
refereeSimilarity of the submitted manuscript to the attached Die Casting Engineer
Trade journal article (May/June 1998) is Striking.
rebuttalThe article in Die Casting Engineer is a summary of the present article.
It is mentioned there that it is a summary of the present article.
There is nothing secret about it.
This article points out that the ``common'' model is totally wrong.
This is of central importance to die casting engineers.
The publication of this information cannot be delayed until
the review process is finished.
refereeIt is not clear to the reader why the ``constant pressure'' and ``constant power''
situations were specifically chosen to demonstrate the author's point.
Which situation is most like that found [likely found] in a die casting machine?
Does the ``constant pressure'' correspond closely to older style machines
when intensifyer [intensifier]
bottle pressure was applied to the injection system unthrottled?
Does the ``constant power'' situations assume a newer machines,
such as Buher Sc, that
generates the pressure required to achieve a desired gate velocity?
Some explanation of the logic of selecting these two situations would be helpful
in the manuscript.
rebuttalAs was stated in the article, these situations were chosen because
they are building blocks but more importantly to demonstrate that the
``common'' model is totally wrong!
If it is wrong for two basic cases
it should be absolutely wrong in any combinations of the two cases.
Nevertheless, an additional explanation is given in Chapter refchap:pQtwo.
refereeThe author's approach is useful?
Gives perspective to a commonly used process engineering method
(pQtwo) in die casting.
Some of the runner lengths chosen (1 meter) might be consider exceptional
in die casting - yet the author uses this to show how much in error an
``average'' value for cd can be.
The author might also note that the North American Die Casting Association and many
practitioners use a ratio of as a design target
The author" analysis reinforces this value as a good target, and that straying
far from it may results in poor design part filling problems (Fig. 5)
rebuttalThe reviewer refers to several points which are important to address.
All the four sizes show large errors (we do not need to take 1[m] to
The one size, the referee referred to as exceptional (1 meter),
is not the actual length but the represented length (read the article again).
Poor design can be represented by a large length.
This situation can be found throughout the die casting industry due to
the ``common'' model which does not consider runner design.
My office is full with runner designs with represent 1 meter length
such as one which got NADCA's
design awardfootnoteto the best of my understanding.
In regards to the area ratio,
please compare with the other referee who claim = 0.8 - 0.95.
I am not sure which of you really represent NADCA's position (I didn't find any
of NADCA's publication in regards to this point).
I do not agree with both referees.
This value has to be calculated and cannot be speculated as the referees
Please find an explanation to this point in the paper or in even
better in Chapter refchap:pQtwo.
refereeThere are several major concerns I have about this paper.
The [most] major one [of these] is that [it] is unclear what the paper
is attempting to accomplish.
Is the paper trying to suggest a new way of designing the rigging for a die
casting, or is it trying to add an improvement to the conventional pQtwo
solution, or is it trying to somehow suggest a `mathematical basis for the
rebuttalThe paper shows that 1) the ``conventional pQtwo solution''
is totally wrong, 2)
the mathematical analytical solution for the pQtwo provides an
excellent tool for studying the effect of various parameters.
refereeThe other major concern is the poor organization of the ideas which
the authors [are] trying to present.
For instance, it is unclear how specific results presented in the results
section where obtained ([for instance] how were the results in Figures 5 and 6 calculated?).
rebuttalI do not understand how the organization of the paper relates to the fact that
the referee does not understand how Fig 5 and 6 were calculated.
The organization of the paper does not have anything do with his understanding
the concepts presented.
In regard to the understanding of how Figure 5 and 6 were obtained,
the referee should referred to an elementary fluid mechanics text book
and combined it with the explanation presented in the paper.
refereeSeveral specific comments are written on the manuscript itself; most of these
were areas where the reviewer was unclear on what the authors meant or areas
where further discussion was necessary.
One issue that is particularly irksome is the authors tendency in sections 1
and 2 to wonder [wander] off with ``editorials'' and other unsupported comments which
have no place in a technical article.
rebuttalPlease show me even one unsupported comment!!
refereeOther comments/concerns include-
refereewhat does the title have to do with the paper?
The paper does not define what a pQ2 diagram is and the results don't really
tie in with the use of such diagrams.
rebuttalThe paper presents the exact analytical solution for the pQtwo
The results tie in very well with the correct pQtwo diagram.
Unfortunately, the ``common'' model is incorrect and so
the results cannot be tied in
refereep.4 The relationship
is a result of the application of
Bernoulli's equation system like that shown in Fig 1. What is the rational or
basis behind equation 1; e.g.
with n =1, 1/2, and 1/4?
rebuttalHere I must thank the referee for his comment! If the referee had
serious problem understanding this point, I probably should have considered adding
a discussion about this point, such as in Chapter refchap:pQtwo.
refereep.5 The relationship between equation 1(a) to 1(c) and a die casting machine as
``poor'', ``common'', and ``excellent'' performance is not clear and needs to
be developed, or at least defined.
rebuttalsee previous comment
refereeIt is well known that cd for a die casting machine and die is not a
In fact it is common practice to experimentally determine cd
for use on dies with `similar' gating layouts in the future.
But because most dies have numerous gates branching off of numerous runners, to
determine all of the friction factors as a function of Reynolds number would be
quite difficult and virtually untractable for design purposes.
Generally die casting engineers find conventional pQ2 approach works quite well
for design purposes.
rebuttalThis ``several points' comment give me the opportunity to discusses
the following points:
I would kindly ask the referee, to please provide the names of any companies whom
``experimentally determine cd.''
Perhaps they do it down under (Australia) where the ``regular'' physics laws do
not apply (please, forgive me about being the cynical about this point.
I cannot react to this any other way.).
Please, show me a company that uses the ``common'' pQtwo diagram and it works.
Due to the computer revolution,
today it is possible to do the calculations of the cd for a specific design
with a specific flow rate (die casting machine).
In fact, this is exactly what this paper all about.
Moreover, today there is a program that already does these kind
of calculations, called DiePerfectTM.
Here the referee introduce a new idea of the ``family'' - the improved constant
In essence, the idea of ``family'' is improve constant cd in which
one assigned value to a specific group of runners.
Since this idea violate the basic physics laws and the produces the opposite
to realty trends it must be abandoned.
Actually, the idea of ``family'' is rather bizarre,
because a change in the design can lead
to a significant change in the value of cd.
Furthermore, the ``family'' concept can lead to a poor design (read about this in
the section ``poor design effects'' of this book).
How one can decided which design is part of what ``family''?
Even if there were no mistakes, the author's method (calculating the cd) is of course
cheaper and faster
than the referee's suggestion about ``family'' of runner design.
In summary, this idea a very bad idea.
What is cd =constant?
The referee refers to the case where cd is constant for specific runner
design but which is not the case in reality.
The cd does not depend only on the runner,
but on the combination of the runner system with the die casting machine
via the Re number.
Thus, a specific runner design cannot have cd ``assigned'' to it.
The cd has to be calculated for any combination runner system with die
I would like to find any case where the ``common'' pQtwo diagram
Please read the proofs in Chapter refchap:pQtwo showing why it cannot work.
refereeDiscussion and results A great deal of discussion focuses on the regions
where 0.1; yet in typical die casting dies 0.8
rebuttalPlease read the comments to the previous referee
refereeIn conclusion, it's just a plain sloppy piece of work
rebuttalI hope that referee does not mind that I will use it as the chapter quote.
referee (the Authors even have
one of the references to their own publications sited incorrectly!).
rebuttalPerhaps, the referee should learn that magazines change names and,
that the name appears in the reference is the magazine name at the time of
writing the paper.
refereeThe following comments are not arranged in any particular order.
refereeGeneral: The text has a number of errors in grammar, usage and spelling that
need to be addressed before publication.
refereep 6 paragraph - The firsts sentence says that the flow rate is a
function of temperature, yet the rest of the paragraph says that it isn't.
rebuttalThe rest of the paragraph say the flow
rate is a weak function of the temperature and that it explains why.
I hope that everyone agrees with me that it is common to state a common assumption
and explain why in that particular case it is not important.
I wish that more people would do just that.
First, it would eliminate many mistakes that are synonymous with research in
die casting, because it forces the ``smart'' researchers to check the major
assumptions they make.
Second, it makes clear to the reader why the assumption was made.
refereep 6 - after Eq 2 - Should indicate immediately that the subscript[s]
refer to the sections in Figure 1.
rebuttalI will consider this, Yet, I am not sure this is a good idea.par
refereep 6 - after equation 2 - There is a major assumption made here that
should not pass without some comment[s]footnoteIs the referee looking for one or several explanations?
``Assuming steady state '' - This assumption goes to
the heart of this approach to the filling calculation and establishes the
bounds of its applicability.
The authors should discuss this point.
rebuttalWell, I totally disagree with the referee on this point.
The major question in die casting is how to ensure the right range of filling time
and gate velocity.
This paper's main concern is how to calculate the cd and determine if the
cd be ``assigned'' to a specific runner.
The unsteady state is only a side effect and has very limited importance
due to AESS.
Of course the flow is not continuous/steady state and is affected by many parameters
such as the piston weight, etc,
all of which are related to the transition point and not to the pQtwo diagram
The unsteady state exists only in the initial and final
stages of the injection.
As a general rule, having a well designed pQtwo diagram will produce
a significant improvement in the process design.
It should be noted that a full paper discussing the unsteady state
is being prepared for publication at the present time.
refereeIn general the organization of the paper is somewhat weak - the introduction
especially does not very well set the technical context for the pQ2 method and
show how the present work fits into it.
rebuttalThe present work does not fit into past work!
It shows that the past work is wrong, and builds the mathematical theory behind
the pQtwo diagram.
refereeThe last paragraph of the intro is confused [confusing].
The idea introduced in the last sentence on page 2 is that the CD should vary
somehow during the calculation, and subsequently variation with Reynolds
number is discussed, but the intervening material about geometry effects is
inconsistent with a discussion of things that can vary during the calculation.
The last two sentences do not fit together well either - ``the assumption of
constant CD is not valid'' - okay, but is that what you are going to talk
about, or are you going to talk about ``particularly the effects of the gate
rebuttalFirstly, cd should not vary during the calculations
it is a constant for a specific set of runner system and die casting machine.
Secondly, once any parameter is changed, such as gate area, cd has to be
Now the referee's statement cd should vary, isn't right and therefore some
of the following discussion is wrong.goodbreak
Now about the fitting question.
What do referee means by ``fit together?''
Do the paper has to be composed in a rhyming verse?
Anyhow, geometrical effects are part of Reynolds number
(review fluid mechanics).
Hence, the effects of the gate area shows that cd varies as well and has to
So what is inconsistent?
How do these sentences not fit together?
refereeOn p 8, after Eq 10 - I think that it would be a good idea to indicate
immediately that these equations are plotted in Figure 3, rather than waiting
to the next section before referring to Fig 3.newline
Also, making the Oz-axis on this graph logarithmic would help greatly in
showing the differences in the three pump characteristics.
rebuttalMentioning the figure could be good idea but I don't agree with you
about the log scale, I do not see any benefits.
refereeOn p. 10 after Eq 11 - The solution of Eq 11 requires full information on the
die casting machine - According to this model, the machine characterized by
Pmax, Qmax and the exponent in Eq 1.
The wording of this sentence, however, might be indicating that there is some
information to be had on the machine other that these three parameters.
I do not think that that is what the authors intend, but this is confusing.
rebuttalThis is exactly what the authors intended.
The model does not confined to a specific exponent or function, but rather gives
Every die casting machine can vary between the two extreme functions,
as discussed in the paper.
Hence, more information is needed for each
individual die casting machine.
refereep 12 - I tend to disagree with the premises of the discussion
following Eq 12.
I think that Qmax depends more strongly on the machine size than does Pmax.
In general, P max is the intensification pressure that one wants to achieve
during solidification, and this should not change much with the machine size,
whereas the clamping force, the product of this pressure and platten are, goes
On the other hand, when one has larger area to make larger casting, one wants
to increase the volumetric flow rate of metal so that flow rate of metal so
that fill times will not go up with the machine size.
Commonly, the shot sleeve is larger, while the maximum piston velocity does not
rebuttalHere the referee is confusing so many different concepts that it will
take a while to explain it properly.
Please find here a attempt to explain it briefly.
The intensification pressure has nothing to do with the pQtwo diagram.
The pQtwo does not have much to do with the solidification process.
It is designed not to have much with the solidification.
The intensification pressure is much larger than .
I give up!! It would take a long discussion to teach you the fundamentals
of the pQtwo diagram and the die casting process.
You confuse so many things that it impossible to unravel it all for you
in a short paragraph.
Please read Chapter refchap:pQtwo or even better read the whole book.
refereeAlso, following Eq 13, the authors should indicate what they mean by ``middle
range'' of the Oz numbers. It is not clear from Fig 3 how
close one needs to get to Oz=0 for the three curves to converge again.
rebuttalThe mathematical equations are given in the paper.
They are very simple that you can use hand calculator to find how much close
you need to go to for your choice of error.
A discussion on such issue is below the level from an academic paper..
refereeBesides being illustrative of the results, part of the value of an example
calculation comes from it making possible duplication of the results elsewhere.
In order to support this, the authors need to include the relationships
that used for CD in these calculations.
rebuttalThe literature is full of such information.
If the referee opens any basic fluid mechanics text book then he can
find information about it.
refereeThe discussion on p 14 of Fig 5 needs a little more consideration.
There is a maximum in this curve, but the author's criterion of being on the
``right hand branch'' is said to be shorter fill time, which is not a criterion
for choosing a location on this curve at all.
The fill time is monotone decreasing with increasing A3 at constant A2, since
the flow is the product of Vmax and A3. According to this criterion, no
calculation is needed - the preferred configuration is no gate whatsoever.
Clearly, choosing an operating point requires introduction of other criteria,
including those that the authors mention in the intro.
And the end of the page 14 discussion that the smaller filling time from
using a large gate (or a smaller runner!!??) will lead to a smaller machine
just does not follow at all.
The machine size is determined by the part size and the required
intensification pressure, not by any of this.
rebuttalOnce again the referee is confusing many issues; let me interpret again
what is the pQtwo diagram is all about.
The pQtwo diagram is for having an operational point at the right gate
velocity and the right filling time.
For any given , there are two possible solutions on the right
hand side and one on the left hand side with the same gate velocity.
However, the right hand side has smaller filling time.goodbreak
And again, the referee confusing another issue.
Like in many engineering situations, we have here a situation in
which more than one criterion is needed.
The clamping force is one of the criteria that determines what machine should
The other parameter is the pQtwo diagram.
refereeIt seems that they authors have obscured some elementary results by
doing their calculations.footnoteIf it is so elementary how can it be
obscured.goodbreak I have broken-out this paragraph for purposes of
ovalboxparboxpagewidthboxFor example, the last sentence of the middle paragraph on p 15 illustrates that
as CD reaches its limiting value of 1, the discharge velocity reaches its
This is not something we should be publishing in 1998.
rebuttalThere is no mention of the alleged
fact of ``cd reaches its limiting value of 1.''
There is no discussion in the whole article about
``cd reaching its maximum (cd=1)''.
Perhaps the referee was mistakenly commenting on different articles (NADCA's book or
an other die casting book) which he has confused with this article.
refereeRegarding the concluding paragraph on p 15:
refereeThe use of the word ``constant'' is not consistent throughout this paper.
Do they mean constant across geometry or constant across Reynolds number, or
rebuttalTo the readers: The referee means across geometry as different geometry
and across Reynolds number as different Re numberfootnoteif the interpretation is not
correct I would like to learn what it really mean..
I really do not understand the difference between the two cases.
Aren't actually these cases the same?
A change in geometry leads to a change in Reynolds number number.
Anyhow, the referee did not consider a completely different possibility.
Constant cd means that cd is assigned
to a specific runner system, or like the ``common'' model in which all
the runners in the world have the same value.
refereeAssuming that they mean constant across geometry, then obviously,
using a fixed value for all runner/gate systems
will sometimes lead to large errors.
They did not need to do a lot calculation to determine this.
rebuttalAnd yet this method is the most used method in
the industry(some even will say the exclusive method).
refereeConversely, if they mean constant across Reynolds number,
i.e. CD can vary through the run as the velocity varies, then they
have not made their case very well.
Since they have assumed steady state and the P3 does not enter into the
calculation, then the only reason that mention for the velocity to vary during
the fill would be because Kf varies as a function of the fill fraction.
They have not developed this argument sufficiently.
rebuttalLet me stress again the main point of the article.
cd varies for different runners and/or die casting machines.
It is postulated that the velocity does not vary during run.
A discussion about is an entirely different issue related to
the good venting design for which remains constant.
refereeIf the examples given in the paper do not represent the characteristics of a
typical die casting machine, why to present them at all? Why are the ``more
detailed calculations'' not presented, instead of the trivial results that are
rebuttalThese examples demonstrate that the ``common'' method is erroneous and
that the ``authors`'' method should be adopted or other methods based on scientific
I believe that this is a very good reason.par
chapterMy Relationship with Die Casting Establishment
I cannot believe the situation that I am in.
The hostility I am receiving from the establishment is unbelievable, as
individual who has spent the last 12 years in research to improve the die
At first I was expecting to receive a welcome to the club.
Later when my illusions disappeared, I realized that it revolves around
money along with avoiding embarrassment to the establishment due to exposing
of the truths and the errors the establishment has sponsored.
I believe that the establishment does not want people to know that they had
invested in research
which produces erroneous models and continues to do so, even though they know these
research works/models are scientifically rubbish.
They don't want people to know about their misuse of money.
When I started my research, I naturally called what was then SDCE.
My calls were never returned.
A short time later SDCE developed into what is now called NADCA.
I had hoped that this new creation would prove better.
Approximately two years ago I wrote a letter to Steve Udvardy,
director of research and education for NADCA ( a letter I never submitted).
Now I have decided that it is time to send the letter and to make it
open to the public.
I have a long correspondence with Paul Bralower, former director of
communication for NADCA, which describes my battle to publish important information.
An open letter to Mr. Baran, Director of Marketing for NADCA, is also attached.
Please read these letters.
They reveal a lot of information about many aspects
of NADCA's operations.
I have submitted five (5) articles to this conference (20th in Cleveland)
and only one was accepted (only 20% acceptance compared to 70% to any
Read about it here.
During my battle to ``insert'' science in die casting, many curious things
have taken place and
I wonder: are they coincidental? Read about these and
please let me know what you think.
section*Open Letter to Mr. Udvardy
9701 West Higgins Road, Suite 880
Rosemont, IL 60018-4721
hbox to textwidthhss January 26, 1998
hbox to textwidthSubject: Questionable ethicshss
Dear Mr. Udvardy:
I am writing to express my concerns about possible improprieties
in the way that NADCA awards research grants.
As a NADCA member, I believe that these possible improprieties could
result in making the die casting industry
less competitive than the plastics and other related industries.
If you want to enhance the competitiveness of the die casting
industry, you ought to support die casting industry ethics
and answer the questions that are raised herein.
Many of the research awards raise serious questions and concerns
about the ethics of the process and cast very serious
shadows on the integrity those involved in the process.
In the following paragraphs I will spell out some of the things I have found.
I suggest to you and all those concerned about
the die casting industry that you/they should help to clarify these questions, and
eliminate other problems if they exist in order to increase the die casting
industry's profits and competitiveness with other industries.
I also wonder why NADCA demonstrates no desire to participate
in the important achievements I have made.
On September 26, 1996, I informed NADCA that Garber's model on the critical slow
plunger velocity is unfounded, and, therefore so, is all the
other research based
on Garber's model (done by Dr. Brevick from Ohio State University).
To my great surprise I learned from the March/April 1997 issue of Die Casting Engineer
that NADCA has once again awarded Dr. Brevick with a grant to
continue his research in this area.
Also, a year after you stated that a report on the results from Brevick's
could be obtained from NADCA,
no one that I know of has been able to find or obtain this report.
I and many others have tried to get this report, but in vain.
It leaves me wondering whether someone does not want others to
know about this research.
I will pay $50 to the first person who will furnish me with this report.
I also learned (in NADCA's December 22, 1997 publication)
that once more NADCA awarded Dr. Brevick with another grant to do research
on this same topic for another budget year (1998).
Are Dr. Brevick's results really that impressive?
Has he changed his model? What is the current model?
Why have we not heard about it?
I also learned in the same issue of Die Casting Engineer that
Dr. Brevick and his colleagues have been awarded another grant
on top of the others to do research on the
topic entitled ``Development and Evaluation of the Sensor System.''
In the September/October 1997 issue, we learned that
Mr. Gary Pribyl, chairman of the NADCA Process Technology Task Group,
is part of the research team.
This Mr. Pribyl is the chairman of the very committee which
funded the research.
Of course, I am sure, this could not be.
I just would like to hear your explanation.
Is it legitimate/ethical to have a man on the
committee awarding the chairman a grant?
Working on the same research project with this Mr. Pribyl
was Dr. Brevick who also received a grant mentioned above.
Is there a connection between the fact that Gary Pribyl cooperated with
Dr. B. Brevick on the sensor project and you deciding to renew Dr. Brevick's
grant on the critical slow plunger velocity project?
I would like to learn what the reasoning for continuing to fund
Dr. Brevick after you had learned that his research was problematic.
Additionally, I learned that Mr. Steve Udvardy was given
a large amount of money to study distance communications.
I am sure that Mr. Udvardy can enhance NADCA's ability in distance learning and
that this is why he was awarded this grant.
I am also sure that Mr. Udvardy has all the credentials needed for such research.
One can only wonder why his presentation was not added to the NADCA proceedings.
One may also wonder why there is a need to do such research when
so much research has already been done in this area by the world's
foremost educational experts.
Maybe it is because distance communication works differently for NADCA.
Is there a connection between Mr. Steve Udvardy being awarded this grant and
his holding a position as NADCA's research director?
I would like to learn the reasons you vouchsafe this money to Mr. Udvardy!
I also would like to know if Mr. Udvardy's duties
as director of education include knowledge and research in this
If so, why is there a need to pay Mr. Udvardy additional monies to do
the work that he was hired for in the first place?
We were informed by Mr. Walkington on the behalf of NADCA in the Nov-Dec
1996 issue that around March or April 1997, we would have the
software on the critical slow plunger velocity.
Is there a connection between this software's apparent delayed appearance and the
fact that the research in Ohio has produced totally incorrect and off-base results?
I am sure that there are reasons preventing NADCA from completing and publishing this
I would just like to know what they are.
I am also sure that the date this article came out (Nov/Dec 1996)
was only coincidentally immediately after I sent you my paper and proposal
on the shot sleeve (September 1996).
What do you think?
Likewise, I learned that Mr. Walkington,
one of the governors of NADCA, also received a grant.
Is there a connection between this grant being awarded to Mr. Walkington
and his position?
What about the connection between his receiving the grant and his former position as
the director of NADCA research?
I am sure that grant was awarded based on merit only.
However, I have serious concerns about his research.
I am sure that these concerns are unfounded, but
I would like to know what
Mr. Walkington's credentials are in this area of research.
The three most important areas in die casting are
the critical slow plunger velocity, the pQtwo diagram,
and the runner system design.
The research sponsored by NADCA on the critical slow plunger velocity
is absolutely unfounded
because it violates the basic physics laws.
The implementation of the pQtwo diagram is also absolutely unsound
because again, it violates the basic physics laws.
One of the absurdities of the previous model is the idea that plunger diameter has
to decrease in order to increase the gate velocity.
This conclusion (of the previous model) violates several physics laws.
As a direct consequence, the design of the runner system (as published
in NADCA literature) is, at best, extremely wasteful.
As you also know, NADCA, NSF, the Department of Energy, and others sponsoring research
in these areas exceed the tens of millions, and yet produce
I am the one who discovered the correct procedure in both areas.
It has been my continuous attempt to make NADCA part of these achievements.
Yet, you still have not responded to my repeated requests for a grant.
Is there a reason that it has taken you
years to give me a negative answer?
Is there a connection between any of the above information and how long it has taken
Please see the impressive partial-list of the things that I have achieved.
I am the one who found Garber's model to be totally and absolutely wrong.
I am also the one responsible for finding the pQtwo diagram implementation
to be wrong.
I am the one who is responsible for finding the correct pQtwo diagram
I am the one who developed the critical area concept.
I am the one who developed the economical runner design concept.
In my years of research in the area of die casting I have not come across
any research that was sponsored by NADCA which was correct and/or
which produced useful results!!
Is there any correlation between the fact that all the important discoveries (that
I am aware of) have been discovered not in-but outside of NADCA?
I would like to hear about anything in my area of expertise supported
by NADCA which is useful and correct?
Is there a connection between the foregoing issues and the fact that so many
of the die casting engineers I have met do not believe in science?
More recently, I have learned that your secretary/assistant, Tricia Margel,
has now been awarded one of your grants and is doing research on pollution.
I am sure the grant was given based on qualification and merit only.
I would like to know what Ms. Margel's credentials in the pollution research
Has she done any research on pollution before?
If she has done research in that area, where was it published?
Why wasn't her research work published?
If it was published, where can I obtain a copy of the research?
Is this topic part of Ms. Margel's duties at her job?
If so, isn't this a double payment?
Or perhaps, was this an extra separated payment?
Where can I obtain the financial report on how the money was spent?
Together we must promote die casting knowledge.
I am doing my utmost to increase the competitiveness of the die casting
industry with our arch rivals: the plastics industry, the composite material
industry, and other industries.
I am calling on everyone to join me to advance the knowledge of the die casting
Thank you for your consideration.
Genick Bar-Meir, Ph.D.
ccNADCA Board of Governors
Anyone who care
about die casting industry
section*Correspondence with Paul Bralower
Paul Bralower is the former director of communications at NADCA.
I have tried to publish articles about critical show shot sleeve and the pQtwo
diagram through NADCA magazine.
Here is an example of my battle to publish the article regarding pQtwo.
You judge whether NADCA has been enthusiastic about publishing this kind of information.
Even after Mr. Bralower said that he would publish it I had to continue my struggle.
textbflarge He agreed to publish the article but
At first I sent a letter to Mr. Bralower (Aug 21, 1997):
Paul M. Bralower
9701 West Higgins Road, Suite 880
Rosemont, IL 60018-4721
Dear Mr. Bralower:
Please find enclosed two (2) copies of the paper ``The mathematical theory
of the pQtwo diagram'' submitted by myself for your review. This
paper is intended to be considered for
publication in textslDie Casting Engineer.
For your convenience I include a disk DOS format with Microsoft WORD
for window format (pq2.wid) of the paper, postscript/pict files of the
figures (figures 1 and 2). If there is any thing that I can do to help
please do not hesitate let me know.
Thank you for your interest in our work.
Dr. Genick Bar-Meir
a short die casting list
He did not responded to this letter, so I sent him an additional one
on December 6, 1997.par
parindent 0 pt
Paul M. Bralower
9701 West Higgins Road, Suite 880
Rosemont, IL 60018-4721
Dear Mr. Bralower:
I have not received your reply to my certified mail to you dated August
20, 1997 in which I enclosed the paper "The mathematical theory of the
pQtwo diagram" authored by myself for your consideration (a cc
was also sent to Larry Winkler from Hartzell). Please consider publishing
my paper in the earliest possible issue. I believe that this paper is of
extreme importance to the die casting field.
I understand that you have been very busy with the last exhibition and
congress. However, I think that this paper deserves a prompt hearing.
I do not agree with your statement in your December 6, 1996 letter to
me stating that "This paper is highly technical-too technical without a
less-technical background explanation for our general readers .
I do not believe that discounting your readers is helpful. I have
met some of your readers and have found them to be very intelligent, and
furthermore they really care about the die casting industry. I believe
that they can judge for themselves. Nevertheless, I have yielded
to your demand and have eliminated many of the mathematical derivations
from this paper to satisfy your desire to have a "simple" presentation.
This paper, however, still contains the essentials to be understood clearly.
Please note that I will withdraw the paper if I do not receive a reply
stating your intentions by January 1, 1998, in writing. I do believe this
paper will change the way pQtwo diagram calculations are made.
The pQtwo diagram, as you know, is the central part of the calculations
and design thus the paper itself is of same importance.
I hope that you really
do see the importance of advancing knowledge in the die casting industry,
and, hope that you will cooperate with those who have made the major progress
in this area.
Thank you for your consideration.
Dr. Genick Bar-Meir
ccBoxter, McClimtic, Scott, Wilson, Holland, Behler, Dupre,
and some other NADCA members
psYou probably know by now that Garber's model is totally and absolutely
wrong including all the other investigations that where based on it, even
if they were sponsored by NADCA. (All the researchers agreed with me in
the last congress)
Well that letter got him going and he managed to get me a letter in
which he claim that he sent me his revisions. Well, read about it
in my next letter dated January 7, 1998.
Paul M. Bralower,
9701 West Higgins Road, Suite 880
Rosemont, IL 60018-4721
Dear Mr. Bralower:
Thank you for your fax dated December 29, 1997 in which you alleged
that you sent me your revisions to my paper ``The mathematical theory of
the pQtwo diagram.'' textbfI never receive any such thing!! All
the parties that got this information and myself find this paper to of
I did not revise my paper according to your comments on this paper,
again, since I did not receive any. I decided to revised the paper since
I did not received any reply from you for more than 4 months. I revised
according to your comments on my previous paper on the critical slow plunger
velocity. As I stated in my letter dated December 6, 1997, I sent you the
revised version as I send to all the cc list. I re-sent you the same version
on December 29, 1997. Please note that this is the last time I will send
you the same paper since I believe that you will claim again that you do
not receive any of my submittal. In case that you claim again that you
did not receive the paper you can get a copy from anyone who is on the
cc list. Please be aware that I changed the title of the paper
(December, 6, 1997 version) to be "How to calculate the pQtwo
I would appreciate if you respond to my e-Mail by January 14, 1998.
Please consider this paper withdrawn if I will not hear from you by the
mentioned date in writing (email is fine) whether the paper is accepted.
I hope that you really do see the importance of advancing knowledge
in the die casting industry, and, hope that you will cooperate with
those who have made the major progress in this area.
Dr. Genick Bar-Meir
pstextbfYou surely know by now that Garber's model is totally and absolutely
wrong including all the other investigations that where based on it
He responded to this letter and changed his attitude
rightlineJanuary 9, 1998.
Dear Mr. Bar-Meir:
Thank you for your recent article submission and this follow-up e-mail.
I am now in possession of your article "How to calculate the pQ2 diagram
correctly." It is the version dated Jan. 2, 1998. I have read
it and am prepared to recommend it for publication in Die Casting Engineer.
I did not receive any earlier submissions of this article, I was confusing
it with the earlier article that I returned to you. My apologies.
However I am very pleased at the way you have approached this article.
It appears to provide valuable information in an objective manner, which
is all we have ever asked for. As is my policy for highly technical
material, I am requesting technical personnel on the NADCA staff to review
the paper as well. I certainly think this paper has a much better
chance of approval, and as I said, I will recommend it. I will let
you know of our decision in 2-3 weeks. Please do not withdraw it-give
us a little more time to review it! I would like to publish it and
I think technical reviewer will agree this time.
Well I waited for a while and then I sent Mr. Bralower a letter
dated Feb 2, 1998.
Dear Mr. Bralower,
Apparently, you do not have the time to look over my paper as you promise.
Even a negative reply will demonstrate that you have some courtesy.
But apparently the paper is not important as your experts told you and
I am only a small bothering cockroach.
Please see this paper withdrawn!!!!
I am sorry that we do not agree that an open discussion on technical
issues should be done in your magazine. You or your technical experts do
not have to agree with my research. I believe that you have to let
your readers to judge. I am sure that there is no other reasons to your
decision. I am absolutely sure that you do not take into your consideration
the fact that NADCA will have to stop teaching SEVERAL COURSES which are
wrong according to this research.
Thank you for your precious time!!
Please note that this letter and the rest of the correspondence with
you in this matter will be circulated in the die casting industry. I am
sure that you stand by your decision and you would like other to see this
correspondence even if they are NADCA members.
Here is the letter I received in return a letter
from Paul Bralower Feb 5, 1998.
Dear Mr. Bar-Meir:
I'll have you know that you have inconvenienced me and others on our
staff today with your untoward, unnecessary correspondence. If you had
a working telephone or fax this e-mail would not be necessary. As
it is I must reply to your letter and take it to someone else's office
and have them e-mail it to you right away.
I tried to telephone you last week on Thurs. 1/29 with the news that
we have agreed to publish your article, ``How to Calculate the pQtwo
diagram correctly.'' I wanted to ask you to send the entire paper,
with graphics and equations, on a disk. Because of the current status
of our e-mail system, I would advise you not to e-mail it. Send it
on any of the following: Syquest, Omega ZIP or Omega JAZ. Use Microsoft
Office 97, Word 6.0 or Word Perfect 6.0.
The problem is I couldn't reach you by phone. I tried sending
you a fax several times Thurs. and last Friday. There was no response.
We tried a couple of different numbers that we had for you.
Having no response, I took the fax and mailed it to you as a letter on
Monday 2/2. I sent Priority 2-day Mail to your attention at Innovative
Filters, 1107 16th Ave. S.E., Minneapolis, Minn, 55414. You should
have received it today at latest if this address is correct for you, which
it should be since it was on your manuscript.
Now, while I'm bending over backwards to inform you of your acceptance,
you have the nerve to withdraw the paper and threaten to spread negative
gossip about me in the industry! I know you couldn't have known I
was trying to contact you, but I must inform you that I can't extend any
further courtesies to you. As your paper has been accepted, I expect
that you will cancel your withdrawl and send me the paper on disk immediately
for publication. If not, please do not submit any further articles.
My response to Paul M. Bralower.
rightline Feb 9, 1998
Dear Mr. Bralower:
Thank you for accepting the paper "How to calculate the pQtwo
diagram correctly". I strongly believe that this paper will enhance the
understanding of your readers on this central topic. Therefore, it will
help them to make wiser decisions in this area, and thus increase their
productivity. I would be happy to see the paper published in Die Casting
As you know I am zealous for the die casting industry.
I am doing my utmost to promote the knowledge and profitability of the die
casting industry. I do not apologize for doing so.
The history of our correspondence
makes it look as if you refuse to publish important information about the
critical slow plunger velocity. The history shows that you lost this paper
when I first sent it to you in August, and also lost it when I resubmitted
it in early December. This, and the fact that I had not heard from you
by February 1, 1998, and other information, prompted me to send the email
I sent. I am sure that if you were in my shoes you would have done the
same. My purpose was not to insults anyone. My only aim is to promote the
die casting industry to the best of my ability. I believe that those who
do not agree with promoting knowledge in die casting should not be involved
in die casting. I strongly believe that the editor of NADCA magazine (Die
Casting Engineer) should be interested in articles to promote knowledge.
So, if you find that my article is a contribution to this knowledge, the
article should be published.
I do not take personal insult and I will be glad to allow you to publish
this paper in Die Casting Engineer.
I believe that the magazine is an appropriate
place for this article. To achieve this publication, I will help you in
any way I can. The paper was written using LaTeX, and the graphics are
in postscript files. Shortly, I will send you a disc containing all the
files. I will also convert the file to Word 6.0. I am afraid that conversion
will require retyping of all the equations. As you know, WORD produces
low quality setup and requires some time. Would you prefer to have the
graphic files to be in TIFF format? or another format? I have enhanced
the calculations resolution and please be advised that I have changed slightly
the graphics and text.
Thank you for your assistance.
Dr. Genick Bar-Meir
section*Is the battle over?
Well, I had thought in that stage that the paper would finally be published as
the editor had promised.
Please continue to read to see how the saga continues.
Dear Paul Bralower:
To my great surprise you did not publish my article as you promised.
You also did not answer my previous letter.
I am sure that you have a good reasons for not doing so.
I just would like to know what it is.
Again, would you be publishing the article in the next issue? any other
published at all? In case that you intend to publish the article,
can I receive a preprint so I can proof-read the article prior to the
Thank you for your consideration and assistance!!
Then I got a surprise: the person dealing with me was changed.
Why? (maybe you, the reader, can guess what the reason is).
I cannot imagine if the letter was an offer to buy me out.
I just wonder why he was concerned about me not submitting
proposals (or this matter of submitting for publication).
He always returned a prompt response to my proposals, yah sure.
Could he possibly have suddenly found my research to be so important.
Please read his letter, and you can decide for yourself.
Here is Mr. Steve Udvardy response on Fri, 24 Apr 1998
I have left voice mail for you. I wish to speak with you about what
appears to be non-submittal of your proposal I instructed you to
forward to CMC for the 1999 call.
I can and should also respond to the questions you are posinjg to
I can be reached by phone at 219.288.7552.
Since the deadline for that proposal had passed long before,
I wondered if there was any point in submitting any proposal.
Or perhaps there were exceptions to be made in my case?
No, it couldn't be; I am sure that he was following the exact procedure.
So, I then sent Mr. Udvardy the following letter.
April 28, 1998
LopeningDear Mr. Udvardy:
Thank you very much for your prompt response on the behalf of Paul
As you know, I am trying to publish the article on the pQtwo diagram.
I am sure that you are aware that this issue is central to die casting
engineers. A better design and a significant reduction of cost would
from implementation of the proper pQtwo diagram calculations.
As a person who has dedicated the last 12 years of his life to improve
the die casting industry, and as one who has tied his life to the
success of the die
casting industry, I strongly believe that this article should be
And what better place to publish it than ``Die Casting Engineer''?
I have pleaded with everyone to help me publish this article.
I hope that you will agree with me that this article should be
If you would like, I can explain further why I think that this article
I am very glad that there are companies who are adopting this
I just wish that the whole industry would do the same.
Again, thank you for your kind letter.
psI will be in my office Tuesday between 9-11 am central time
I am sure that Mr. Udvardy did not receive the comments of/from the referees
(see Appendix refchap:referee).
And if he did, I am sure that they did not do have any effect on him whatsoever.
Why should it have any effect on him?
Anyhow, I just think that he was very busy with other things so he did
not have enough time to respond to my letter.
So I had to send him another letter.
LopeningDear Mr. Udvardy:
I am astonished that you do not find time to answer my letter dated
Sunday, April, 26 1998 (please see below copy of that letter).
I am writing you to let you that there is a serious danger in continue
to teach the commonly used pQtwo diagram. As you probably know (if you do
know, please check out IFI's web site www.dieperfect.com),
the commonly used pQtwo diagram as it appears in NADCA's books violates
the first and the second laws of thermodynamics, besides numerous other
common sense things. If NADCA teaches this material,
NADCA could be liable for very large sums of money to
the students who have taken these courses. As a NADCA member,
I strongly recommend that these classes be suspended until the
instructors learn the correct procedures.
I, as a NADCA member, will not like to see
NADCA knowingly teaching the wrong material and moreover being sued for
I feel that it is strange that NADCA did not publish the information
critical slow plunger velocity and the pQtwo diagram and how to do them
I am sure that NADCA members will benefit from such knowledge.
I also find it beyond bizarre that NADCA does not want to cooperate with
made the most progress in the understanding die casting process.
But if NADCA teaching the wrong models might
ends up being suicidal and I would like to change that if I can.
Thank you for your attention, time, and understanding!
Dr. Genick Bar-Meir
psHere is my previous letter.
Now I got a response. What a different tone.
Note the formality (Dr Bar-Meir as oppose to Genick).
May 19, 1998
LopeningDear Dr Bar-Meir,
Yes, I am here. I was on vacation and tried to contact you by phone
before I left for vacation. During business travel, I was sorry to not
be able to call during the time period you indicated.
As Paul may have mentioned, we have approved and will be publishing
your article on calculating PQ2. The best fit for this is an upcoming
issue dedicated to process control. Please rest assured that it will
show up in this appropriate issue of DCE magazine.
Since there has been communications from you to Paul and myself and
some of the issues are subsequently presented to our Executive Vice
President, Dan Twarog, kindly direct all future communications to him.
This will assist in keeping him tied in the loop and assist in getting
responses back to you. His e-mail address is Twarog@diecasting.org.
Why does Mr. Udvardy not want to communicate with me and want me to write to
Executive Vice President?
Why did they change the title of the article and omit the word
I also wonder about the location in the end of the magazine.
I have submitted other proposals to NADCA, but really never received a reply.
Maybe it isn't expected to be replied to? Or
perhaps it just got/was lost?
section*Open letter to Leo Baran
In this section an open letter to Leo Baran is presented.
Mr. Baran gave a presentation in Minneapolis on May 12, 1999,
on ``Future Trends and Current Projects'' to ``sell'' NADCA to its
At the conclusion of his presentation, I asked him
why if the situation is so rosy as he presented, that so many companies
are going bankrupt and sold.
I proceeded to ask him why NADCA is teaching so many erroneous models.
He gave me Mr. Steve Udvardy's business card and told me that he has no
knowledge of this and that since he cannot judge it, he cannot discuss it.
Was he prepared for my questions or was this merely a spontaneous reaction?
Dear Mr. Baran,
Do you carry Steve Udvardy's business card all the time?
Why do you not think it important to discuss
why so many die casting companies go bankrupt and are sold?
Is it not important for us to discuss why there are so many
financial problems in the die casting industry?
Don't you want to make die casting companies more
And if someone tells you that the research sponsored by NADCA is rubbish,
aren't you going to check it?
Discuss it with others in NADCA?
Don't you care whether NADCA teaches wrong things?
Or is it that you just don't give a damn?
I am sure that it is important for you.
You claimed that it is important for you in the presentation.
So, perhaps you care to write an explanation in the next NADCA magazine.
I would love to read it.
section*Is it all coincidental?
I had convinced Larry Winkler in mid 1997 (when he was
still working for Hartzell), to ask Mr. Udvardy why
NADCA continued support for the wrong models (teaching the erroneous
Garber's model and fueling massive grants to Ohio State University).
He went to NADCA and talked to Mr. Udvardy about this.
After he came back, he explained that they told him
that I didn't approach NADCA in the right way.
(what is that?)
His enthusiasm then evaporated,
and he continues to say that, because NADCA likes evolution and not
revolution, they cannot support any of my revolutionary ideas.
He suggested that I needed to learn to behave before NADCA would
ever cooperate with me.
I was surprised and shaken.
``What happened, Larry?'' I asked him.
But I really didn't get any type of real response.
Later (end of 1997) I learned he had received NADCA's design award.
You, the reader, can conclude what happened; I am just supplying you
with the facts.
Several manufacturers of die casting machines, Buler, HPM, Prince, and UBE
presented their products in Minneapolis in April 1999.
When I asked them why they do not adapt the new technologies,
with the exception of the Buler, the response was complete silence.
And just Buler said that they were interested; however, they never later called.
Perhaps, they lost my phone number.
A representative from one of the other companies even told me
something on the order of
``Yeah, we know that the Garber and Brevick models are totally wrong, but
we do not care; just go away-you are bothering us!''.
I have news for you guys: textbfthe new knowledge is here to stay
and if you want to make the die casting industry prosper, you
should adopt the new technologies.
You should make the die casting industry prosper so that you will
prosper as well; please do not look at the short terms as important.
The next issue of the Die Casting Engineer
(May/Jun 1999 issue) was dedicated to machine products.
Whether this was
coincidental, you be the judge.
I submitted a proposal to NADCA (November 5, 1996)
about Garber/Brevick work (to which I never received a reply).
Two things have happened since: I made the proposal(in the proposal I demonstrate that
Brevick's work from Ohio is wrong) 1) publishing of the article by Bill Walkington
in NADCA magazine about the ``wonderful research'' in Ohio State University
and the software to come.
2)a ``scientific'' article by EKK.
During that time EKK also advertised how good their software was for shot sleeve
Have you seen any EKK advertisements on the great success of
shot sleeve calculations lately?
Here is another interesting coincidence,
After 1996, I sent a proposal to NADCA, the cover page of DCE showing the
beta version of software for calculating the critical slow plunger velocity.
Yet, no software has ever been published.
Is it accidental that the author of the article in the same issue
was Bill Walkington.
And after all this commotion I was surprised to learn
in the (May/June 1999) issue of DCE magazine
that one of the Brevick group
had received a prize (see picture below if I get NADCA permission).
I am sure that Brevick's group has made so much progress in the last year that
this is why the award was given.
I just want to learn what these accomplishments are.
mnoteput the picture of Brevick, Udvardy and price guy
For a long time NADCA described the class on the pQtwo diagram
as a ``A close mathematical description.''
After I sent the paper and told them about how the pQtwo diagram
is erroneous, they change the description.
Well it is good, yet they have to say that in the past material was wrong and
now they are teaching something else.
or are they?
I have submitted five (5) papers to the conference ( in Cleveland)
and four (4) have been rejected on the grounds well, you can read the letter
Here is the letter from Mr. Robb.
rightline17 Feb 1999
The International Technical Council (ITC) met on January 20th to
review all submitted abstracts. It was at that time that they
downselected the abstracts to form the core of each of the 12
sessions. The Call for Papers for the 1999 Congress and Exposition
produced 140 possible abstracts from which to choose from, of this
number aproximately 90 abstracts were selected to be reviewed as final
papers. I did recieve all 5 abstracts and distribute them to the
appropriate Congress Chairmen. The one abstract listed in your
acceptance letter is in fact the one for which we would like to review
the final paper. The Congress Chairmen will be reviewing the final
papers and we will be corresponding with all authors as to any changes
revisions which are felt to be appropriate.
The Congress Chairmen are industry experts and it is there sole
discretion as to which papers are solicited based on abstract topic
and fit to a particular session.
It is unfortunate that we cannot accept all abstracts or papers which
are submitted. Entering an abstract does not constitue an automatic
acceptance of the abstract/or final paper.
Thank you for your inquiry, and we look forward to reviewing your
Dennis J. Robbgoodbreak
I must have submitted the textbfworst kind of papers otherwise.
How can you
explain that only 20% of my papers (1 out of 5) accepted.
Note that the other researchers' ratio of acceptance on their papers is 65%,
which means that other papers are three times better than mine.
Please find here the abstracts and decide if you'd like to hear such
topics or not.
Guess which the topic NADCA chose, in what session and on what day (third day).
subsection*A Nobel Tangential Runner Design
The tangential gate element is commonly used in runner designs.
A novel approach to this runner design has been developed to achieve
better control over the needed performance.
The new approach is based on scientific principles in which the
interrelationship between the metal properties and the geometrical
parameters is described.
subsection*Vacuum Tank Design Requirements
Gas/air porosity constitutes a large part of the total porosity.
To reduce the porosity due to the gas/air entrainment,
vacuum can be applied to remove the residual air in the die.
In some cases the application of vacuum results in a high quality
casting while in other cases the results are not satisfactory.
One of the keys to the success is the design of the vacuum system,
especially the vacuum tank.
The present study deals with what are the design requirements on the
Design criteria are presented to achieve an effective vacuum system.
subsection*How Cutting Edge technologies can improve your Process Design
A proper design of the die casting process can reduce the
lead time significantly.
In this paper a discussion on how to achieve
a better casting and a shorter lead time
utilizing these cutting edge technologies is presented.
A particular emphasis is given on the use of the simplified
subsection*On the effect of runner design on the reduction of air
entrainment: Two Chamber Analysis
Reduction of air entrapment reduces the product rejection rate and always
is a major concern by die casting engineers.
The effects of runner design on the air entrapment have been
disregarded in the past.
In present study, effects of the runner design
characteristics are studied.
Guidelines are presented on how to improve the
runner design so that less air/gas are entrapped.
subsection*Experimental study of flow into die cavity: Geometry and
The flow pattern in the mold during the initial part of the
injection is one of the parameters which determines
the success of the casting.
This issue has been studied experimentally.
Several surprising conclusions can be drawn from the experiments.
These results and conclusions are presented and can be used by
the design engineers in their daily practice to achieve better casting.
At the 1997 NADCA conference I had a long conversation with
Mr. Warner Baxter.
He told me that I had ruffled a lot of feathers in NADCA.
He suggested that if I wanted to get real results, I should be politically active.
He told me how bad the situation had been in the past and how much NADCA had improved.
But here is something I cannot understand: isn't there anyone who cares
about the die casting industry and who wants it to flourish?
If you do care, please join me.
I actually have found some individuals who do care and are supporting my efforts
to increase scientific knowledge in die casting.
Presently, however, they are a minority.
I hope that as Linux is liberating the world from Microsoft, so too we can
liberate and bring prosperity to the die casting industry.
After better than a year since my first (and unsent) letter to Steve Udvardy,
I feel that there are things that I would like to add to
the above letter.
After my correspondence with Paul Bralower, I had to continue to press them
to publish the article about the pQtwo.
This process is also described in the preceding section.
You, the reader, must be the judge of what is really happening.
Additionally, open questions/discussion topics to the whole die
casting community are added.
What happened to the Brevick's research?
Is there still no report?
And does this type of research continue to be funded?
Can anyone explain to me how NADCA operates?
Is NADCA, the organization, more important than the die casting industry?
chapter Density change effects
In this appendix we will derive the boundary condition for phase change with
a significant density change.
Traditionally in die casting the density change is assumed to be insignificant
in die casting.
The author is not aware of any model in die casting that take this phenomenon into
In materials like steel and water the density change isn't large enough or it does
not play furthermore important role.
While in die casting the density change play a significant role because a large
difference in values for example aluminum is over 10%.
Furthermore, the creation of shrinkage porosity is a direct consequence of the
captionThe control volume of the phase change
A constant control volumefootnoteA discussion on the mathematical aspects are
left out. If explanation on this point will be asked by readers I will added it.
is constructed as shown in figure refphase:fig:cv.
Solid phase is on the right side and liquid phase is on the left side.
After a small time increment the moved into the the dashed line at a distance .
The energy conservation of the control volume reads
d over dt int_V rho h dV =
- int_A rho h v_i dA +
int _A k Px T oPx n dA
Analogy the mass conservation for the control volume is
d over dt int_V rho dV =
- int_A rho v_i dA
The equations (refphase:eq:energyConservation) and
(refphase:eq:massConservation) do not have any restrictions of the liquid movement
which has to be solved separately.
Multiply equation (refphase:eq:energyConservation)
by a constant results in
d over dt int_V rho h_l dV =
- int_A rho h_l v_i dA
Subtraction equation (refphase:eq:mass_hl) from equation
d over dt int_V rho (h-h_l ) dV =
- int_A rho (h - h_l ) v_i dA +
int _A k Px T oPx n dA
The first term on the right hand side
composed from two contributions: one) from the liquid side and two) from solid side.
At the solid side the contribution is vanished because
is zero due to is identically zero
(no movement of the solid, it is a good assumption).
In the liquid phase the term is zero (why? mnoteput explanation or
question) thus the whole term is vanished we can write the identity
int_A rho (h - h_l ) v_i dA equiv 0
where is the velocity at the interface.
The first term of equation (refphase:eq:energy_hl ) can be expressed in the
term of the c.v.footnoteplease note some dimensions will canceled each
other out and not enter into equationsssss
mnotemaybe the derivations are too long. shorten them?
d over dt int_V rho (h - h_l ) dV & = & overbracerho_s Atwo (h_s - h_l )
- rho_s Aone (h_s - h_l ) ^solid +
overbraceleft( cdots (h_l - h_l ) right)^liquid = 0
& = & ( rho_s (h_s - h_l ) ) dx odt = rho_s (h_s - h_l ) v_n
liquid side contribution is zero since
and the solid
contribution appears only in transitional layer due to transformation liquid to solid.
The second term on right hand side of equation (refphase:eq:energy_hl) is simply
int _A k Px T oPx n dA =
k_s Px T oPx n - k_l Px T oPx n
Thus, equation (refphase:eq:energy_hl) is transformed into
rho_s (h_s - h_l ) v_n = k_s Px T oPx n - k_l Px T oPx n
It is noteworthy that the front propagation is about 10previously was calculated.
Equation (refphase:eq:rightSide) holds as long as the transition into solid is
abrupt (sharp transition).
For the case of where the transition to solid occurs over temperature range
we have create three zones.
Mathematically, it is convenient to describe the
the mushy zone boundaries by two boundary conditions.
The creation of voids is results of density changes which change
the heat transfer mechanism from conduction to radiation.
The location of the void depends on the crystallization and surface tension
The possibility of the ``liquid channels'' and the flow of semi-solid and even
solid compensate for this void.
Yet, one has to take into consideration the pressure effect
The liquidation temperature and the latent heat are affected somewhat by the
At pressure between the atmospheric to typical intensification pressure the
temperature and latent heat are effected very mildly.
However, for pressure near vacuum the latent heat and the temperature are
effected more noticeably.footnoteI have used Clapyron's equation to estimate the change in temperature
to be over 10 degrees (actually about [C]).
However, I am not sure of this calculations and I had not enough time to check it
in the literature.
If you have any knowledge and want to save me a search in the library, please drop
me a line.
The velocity of the liquid metal due to the phase change can be related to the front
propagation utilizing the equation (refphase:eq:massConservation).
The left hand side can be shown to be
The right hand side is reduced into only liquid flow and easily can be shown
to be .
left( rho_s - rho_l right) v_n + rho_l v_l = 0 nonumber
left( hatrho - 1 right) = v_l over v_n
where is the density ratio, .
chapter Fanno Flow
The flow of air trough the venting system is a flow of compressible
There are three ideal models that can potentionaly discribe
The flow of the air/gas is adiabtic i.e. no heat transer is negligible
and can be ignored.
This is the case where process is very fast and heat transer mechanisms are
considerably slower (see more discusion about dimensionless number in
This kind of is known as Fanno flow.
another possiblity is there is an heat transer and the simplist possible
case is when this heat transfer is a constant.
The heat transfer is significant in case where there is chemical reactions
sometime refered to as combusion.
This flow is named on Lard Reyleigh.
A case between the two previous case is the isothermal case.
The flow is has heat transfer but is low enogh to keep the temperature
This is the case when a gas flows for a long distance (in order of
kilometers). In such cases,
the gas temperatue is equal to sorronding temperature.
If the sounding are in uniform temperature (that is simplist case
which we like) is call isothermal case.
Mathematicaly, it is the simplist case footnote I prefere to teach this
material first in my casses. The real simplist case is the isontropic flow
for which the pressure is constat in const conduct area..
In die casting, the air/gas flows from the cavity to sourding in
very rapid manner.
This situation is very close the first model we discribed before.
Hence, we can assume that for many of the cases the flow is resinably
adiabticfootnotein poor design the metal drops flow with the
air and solidfied. The heat is relead to the air and the air temperature
is increased. This analysis is much more complicated and depented on the
flow. Presently, there is no model to account for it and to find the error
in the assumption of idiabic flow..
Therefore, we introduce the Fanno flow and again in a simplist form.
captionControl volume of the gas flow in constant cross section
Consider a gas flows through a conduit with a friction (see Figure
mnoteadd a figure with an element volume very thin
The mass conservation for the control volume is
rho_1 Vone = rho_2 Vtwo
The energy conservion (under the consriction of ideabtic flow) reads
T_0_1 = T_1 + V_1^2 over 2 C_p0
= T_2 + V_2^2 over 2 C_p0
The force acting on the gas is the friction and
the momentum conservation reads
-AdP -tau_w dA = mdot dV
For simplfy the presentation/footnotenot nessarly for the presentation
can be close to circular we assume the conduit to be a circular
-dP + tau_w dA_w over A = mdot over A dV
is equal to .
Utilizing the definiation of the firction factor
and we obtain the following
-dP - 4 over D f dx ( 1/2 rho V^2 ) = mdot over A dV
Utilizing the definition of the sound speed one can obtain the following
- dP over P - 4 f dx over D left( kM^2 over 2right) =
kM^2 dV over V
Converting the exprestion for () and for * in term of the
Mach nubmer yeilds
4 f dx over D = left( 1 - M^2 right) dM^2
kM^4 ( 1 + k-1 over 2M^2
Intergating last equation yeild
4 over D int^x_max_x f dx =
1 over k 1 - M^2 over M^2 + k+1 over 2kln k+1 over 2M^2
over 1+ k-1 over 2M^2
The results of this equation are ploted in Figure
captionFanno flow as a function of fld
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copyright Dec , 2006
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