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Parent - By deisel (*) Date 12-12-2012 19:26
That makes sense about the gases and the different sizes of the current. but does that mean the different polarities affect the gases differently? And to be an engineer requires a good understanding of mathematics doesn't it? I'm terrible at math
- - By deisel (*) Date 12-09-2012 01:43
Yea I spent 18 years bothering my dad with a ton of questions, now that I'm going to school I ask Larry all my questions.  As for the engineering degree I'm not so sure I'm cut out for that; I like hands on work too much and need to spend a few years working before I could afford more school.  I really appreciate your research welderbrent and everybody.  By the way that's really awesome that you understand the automotive aspect superflux. I have to study for my stick welding final but if I have time I'm going to do some searching for this subject
Parent - By RonG (****) Date 12-09-2012 22:20
Kara, FYI, Hands on people are some of the best Engineers.
- - By deisel (*) Date 12-12-2012 15:40
Sorry I haven't posted anything, I have limited access to the internet and I have to talk to Larry more first, he's good at translating physics into farmer talk.  Once I read through all the posts and get a good understanding of them I'll comment again.
Parent - - By Northweldor (***) Date 12-12-2012 19:22 Edited 12-12-2012 19:30
Deisel:

This is my attempt at explaining
" Why does SMAW have greater penetration with EP vs GTAW having greater penetration with EN ?"
(without much reference to particle physics,since I obviously don't know enough!).

First, I think most would agree that a major factor. in achieving penetration, is the heat transmitted to the weld puddle, by various means, through the arc,  in both processes. This is called thermal efficiency.

In GTAW,  the most heat energy is transferred to the weld puddle in EN, making this polarity more thermally efficient. When the polarity is switched to EP, then the major part of the heat energy is focused on the electrode, and this makes the weld puddle cooler and less penetrating than on EP, or less thermally efficient. Also heat energy is dissipated through the electrode into the shielding gas and electrode holder.

In SMAW, the most heat energy is transmitted to the weld puddle in EP, because most heat is concentrated on the electrode, as in GTAW, but since the electrode is being consumed, much of this energy is transferred directly back  to the weld pool with the molten metal, making the weld pool hotter. In SMAW - EN,  the weld pool is cooler since less heat being on the electrode also means less molten metal being transferred to the weld pool, and therefore, EN is less thermally efficient and penetrating.

This is also compounded with other factors in SMAW, such as the fact that the plasma column is directed and focused by the coating crater, (coating melting slower than the core metal) in a way similar to a hose nozzle. This is not as efficient in GTAW, which has a sort of pear-shaped column that is controlled mainly by the shape of the electrode. (In some automated GTAW processes, greater plasma control is achieved with a magnetic field). Another factor influencing thermal efficiency in GTAW EN and EP is that the weld pool is cooled by the feeding of the filler rod, and  the flow of shielding gas.  In SMAW, the slag cover slows the weld pool cooling and increases penetration well. THis is all coupled with the fact that, according to EsabU, there are 9 different purposes for the flux in SMAW, and many hundreds of ingredients which could affect penetration.

Given the above, you might expect SMAW to have greater thermal efficiency than GTAW, and in fact, it does.

I hope the above doesn't have many errors, and that someone will correct them quickly, if  it does. I also hope that it doesn't require too much translation.
Parent - - By deisel (*) Date 12-12-2012 19:33
That makes a lot of sense,  I think I understand now. So it is mostly a matter of where the heat is directed right? If tig welders used consumable tungsten which deposited filler instead of using filler rod we would use dcep in that process like in stick welding, correct?
Parent - By Northweldor (***) Date 12-12-2012 22:54 Edited 12-12-2012 22:57
I will have to think about those questions, because there are many gases, metal vapors, and additives involve in the SMAW plasma that also affect penetration and heat transfer. However, your idea does fit with EP being used in GMAW because the heat is directed to the end of the wire in short circuit welding, and GTAW is using a process more closely related. Also, I think we should wait and see what others think about this theory.
Parent - By Northweldor (***) Date 12-15-2012 22:21
"Should the governing mechanisms, driving the penetration depth to increase at DC EP with the common fusion welding processes (as listed), suddenly switch to act inversely? Just because the "consumable" welding electrode's being replaced by a "non-consumable"? Would that prove reasonable in a physics sense? I do really not know. "...

Electrode:

What is wrong with my answer above?
Parent - - By Lawrence (*****) Date 12-20-2012 14:39 Edited 12-20-2012 14:42
Ok Northwelder..

Since you asked.

I really loved and appreciated your helpful posts..    I've put as few posts into this thread as possible... Diesel already knows what I think... Thus I turned her loose on you all   :)

The only small part I can't personally get my brain around is this:  (and I'm not sure I can communicate my question back to you clearly enough)

"In SMAW - EN,  the weld pool is cooler since less heat being on the electrode also means less molten metal being transferred to the weld pool, and therefore, EN is less thermally efficient and penetrating."

I agree that less heat will be found EN on a SMAW electrode end... This part makes sense...  But the remainder of heat should be at the puddle right?   So why less heat in the weld overall, that would lead to less penetration?

When I run this particular scenero through my foggy head... I visualize E6013 or E7014 electrodes that are by design able to run EN, EP and AC.

I will NOT say anything is wrong... Just parts I don't fully grasp myself just yet.
Parent - By Northweldor (***) Date 12-21-2012 13:32
Lawrence:

I agree that this statement is weak, and I think I better do some more research, especially on the differences in actual deposition rates for dual polarity rods. I was assuming that the physical transfer of molten metal outweighed the increased heat of the weld plasma on the weld pool, and that may be wrong. Thanks for pointing that out!
- - By Northweldor (***) Date 12-19-2012 12:35
electrode seems to have lost interest.

Would anyone explain what is wrong with my explanation of the answer to the original question, posted above? I don't see anything in electrode's explanation that doesn't agree with mine, but I may have missed something. If so, could you point it out?
Parent - - By welderbrent (*****) Date 12-19-2012 16:14
He may not be available at the present.  He stated a couple of compliments about your posts during part of this.  No one said there was necessarily anything wrong with your position.  To a great extent many of the posts/opinions here all play an interacting role in the complete answer.  And, only extensive scientific research can truly answer and/or confirm the conclusions stated.  But, he posted as briefly and accurately as he could, from his perspective, how to reach the answer from physics and mathematics.  And even at that it left some question as to the absoluteness of the conclusion.

Have a Great Day,  Brent
Parent - - By Northweldor (***) Date 12-20-2012 13:29
Brent:

I fully realize that SHE might be busy, and will look forward to a reply from her sometime in the future.

However, you have the wrong idea. I'm not looking for compliments!

I was hoping to get evaluation and criticism from the many more experienced and knowledgeable people on here, with regard to whether my answer above is a  valid response to the question Lawrence and Deisel posed. I would like your evaluation, for example, which you really didn't give above.

I disagree that "...only extensive scientific research can truly answer and/or confirm the conclusions stated. ..."  I think most of the research on polarity effects in fusion welding has already been done, but is difficult to find and interpret in answer to the specific question above. I am presently looking further, and have found many GTAW/GMAW studies, fueled by economics, but so far, nothing bearing directly on this question. So, you, or anyone, who would like to evaluate what i said above as an answer, would be welcome, and might point me in a different direction!
Parent - - By jwright650 (*****) Date 12-20-2012 13:48
Hi Ron....I agree, this thread has been very interesting...wish I had more to add but most of you guys have covered things pretty well. I'm thinking the answers are here somewhere, but as a simpleton, I don't know how to extract them so that I can understand them and be able to explain it to someone else who may ask the same question.(as in Lawrence's case with a student)
Parent - - By Northweldor (***) Date 12-21-2012 13:49
John:

It was your comment at the very beginning that pointed me in this direction, when you said that you thought that the reason was rooted in a consumable vs a non-consumable electrode, so if you can point out more directly what you had in mind at the time, I would appreciate it.  I plan to continue researching this whenever I have time.
Parent - By jwright650 (*****) Date 12-21-2012 14:20
If I get a few minutes(we are having our Christmas breakfast-luncheon today here at work), I will try to type out what I was reading in that book and see if you guys think it helps us get any farther down the road towards a simpler explanation.
Parent - - By electrode (***) Date 12-20-2012 17:46
Sir,

is it I who's meant when you're saying: "Electrode: What is wrong with my answer above?"?

and

"electrode seems to have lost interest."?

1. With all due respect. You should address to me personally when obviously talking about me.

2. Calm yourself. Neither 'electrode' has "lost interest" on what's driving him for over 3 decades nor this seems likely to occur someday.

3. I kindly ask you to take this advice serious. You should not try to open Pandora's box when discussing with me, since I believe you might see things, terrifying to you.

Hence, I wish you to act respectful by all means, when phrasing about me or directly corresponding with me.

Learning this simple lesson, separates the men from the boys.

Having said this, I would like to quickly come to your "answer" whichever is meant here but; I guess it is this, you're speaking about:

http://www.aws.org/cgi-bin/mwf/topic_show.pl?pid=240924#pid240924

To be honest and free and frank. You wouldn't receive any compliment from me for this.

I think, what you're doing is mingling ingredients taken from different sources, hoping then to hit the nail - at least this is my perception and definitely not meant offending.

But if this is o.k. to you. Well Sir, then of course it should be o.k. to me as well. At the end of the day, this is an open forum.

So, keep on going hence to cite from "EsabU" leaflets that try to tell you there's "many hundreds of ingredients which could affect penetration", or quote from cool looking colourful "Praxair handbooks", that want to make you believe to have understood the "physics of an electron" but ruminating theories proven obsolete for long already.

Why not using your own brain instead, which I can learn you're apparently blessed with? Hence, and for sure, I do not consider you a member of this funny group of "welders":

http://www.youtube.com/watch?v=p_-2Apzy5mc&feature=related 

I'm sure thus you will find the discrepancies in your "answer" by yourself, or as already been written in the Holy Scripture: "Be doers of the word and not hearers only, deluding yourselves." (Letter of James 1:22).

What a pity. I not know whether this was really necessary, moreover so shortly before Christmas.

Look at the young lady. Her interest was pure, only driven by her thirst for knowledge, entirely free of any vain affectation.
The reason for me contributing some simple basic considerations to this thread.

Your way however, of "asking" or rather demanding answers is something that's just boring to me in person.

Funny, that obviously you didn't understand one single piece from all the 8843 words (if I did count correctly) that I have been writing along this thread.

Again. No offence. Just my impression. And now, to assure you "Northweldor". I will close this case.

P.S. Thanks to "welderbrent" however, who could put my mind at rest. Reading his kind response: http://www.aws.org/cgi-bin/mwf/topic_show.pl?pid=241210#pid241210, which I am fully, I repeat, fully, agreeing with, makes me hoping that at least one (1) fellow did understand what I was actually meaning.
Parent - By Northweldor (***) Date 12-21-2012 14:02
electrode:

Wow! I'm not sure what I did to cause you to unleash the vitriol above, but I think this is a very offensive reaction to whatever it was (inserting "no offence" doesn't make it less offensive). Perhaps, when you calm down, you can pm me, and try to make my little brain understand.:confused:
- - By deisel (*) Date 01-30-2013 20:37
Hi, :)

Break is over, has been for a couple weeks I just haven't gotten enough time to post. I have another although unrelated question.  GMAW has open circuit voltage, and I was just wondering since the gun has a trigger mechanism controlling the current if it would be at all possible or practical to use high frequency to start the arc.  And why is GTAW the only process, (that I am aware of) that uses super imposed high frequency to start the arc instead of open circuit voltage?  I realize it needs high frequency with ac but is that the only reason it uses high frequency instead of open circuit voltage?
Parent - - By RonG (****) Date 01-30-2013 21:46
I should think the main function of the Hi-Freq in GTAW is to preserve the fine pointed electrode and keep Tungsten out of the weld. I have a lift start machine at home and it can be hard on the Tungsten. Just saying,,,
Parent - - By welderbrent (*****) Date 01-30-2013 22:15
AAAWWW, but the question for this girl is...WHY is it hard on the tungsten and would it also be of benefit in other applications/processes? (right Diesel?)

It is also used for GTAW-EN to start the arc in order to maintain tungsten quality, arc start quality, etc.  Can't tell you why or how at the moment.  Will have to start looking things up and/or someone else will climb in and do their normal wonderful jobs.

Have a Great Day,  Brent
Parent - By RonG (****) Date 01-30-2013 23:59
Lol ok!
Same as in "Scratch Start" GTAW (the EN goes without saying) “Lift Start” requires the Tungsten to make contact with the work and the only accessible place is the point and as a result the point will deteriorate.

If you switch poles (GTAW-EP) you will not maintain a point on the Tungsten, due to the fact we have already established being, the majority of the heat would be in the electrode.
Parent - - By OBEWAN (***) Date 01-30-2013 22:47
The difference is mostly due to the use of a non-consumable vs. a consumable electrode.  If you have not already covered the subject of short circuiting mode for GMAW you soon will.  In short circuiting mode, the wire touches the work and shorts out, and then burns back with an arc, over and over again at a very high frequency.  Only spray arc GMAW mode has a continuous arc.  So, if you are going to weld in spray arc mode it would only have probably one short circuit.  With either mode we don't care that the electrode stubs out because it is a consumable, unlike the tungsetn which we do not want in our welds.
Parent - - By welderbrent (*****) Date 01-31-2013 04:13
Okay Obewan, now then, aren't there some models of SMAW portable machines that incorporate a high frequency while welding?  You hear the arc 'squeek' the whole time you are welding (reminds me of fingernails on a chalkboard when in grade school).  Or is that a different function that is causing that?  And are there any benefits if that is what it is? 

Have a Great Day,  Brent
Parent - - By ssbn727 (*****) Date 02-01-2013 05:57
To answer your question Brent... That noise you hear is HF but, it utilized for a totally different purpose than what traditional HF is used for GTAW.
What I'm talking about is the inverter within the power source is acting like a supercharger in order to generate more power output even though the size of the components are much smaller when compared to a traditional AC/DC Power source... The inverter increases the frequency of electricity from 60 hz in the US, to quite a few thousand hertz in order to increase it's throughput even though from the input side of the power source, very little electricity is being drawn in by the power source when compared to older types of power sources that depended on a greater draw of electricity and need much, much larger components in order to achieving comparable output...

These inverter type power sources are also more efficient than the older types as well as less costly to operate because of the fact that they draw much less electricity @ the input side and they're more portable also... There's whole lot more to explain but, I'm tired and need to get some shut eye so, if anybody else wants to jump in please, be my guest!:eek::lol::wink::cool:

Respectfully,
Henry
Parent - - By welderbrent (*****) Date 02-01-2013 19:24 Edited 02-01-2013 19:26
Thank you Henry.  Actually...I understand most of that.  i was asking the questions in line with what Obewan had already posted to keep some of the HF conversation going and trying to keep it focused on the different processes themselves, not so much the machine.  But, your answers do explain some of the basis for the condition and that it is indeed an HF operation.

So, in your opinion and great amount of expertise and knowledge (and that is meant as a compliment) does this improve the actual arc condition and resultant weld quality when initiating the arc?  Running the bead? Finished weld and it's metallurgical properties?

We have already covered some ground as to it's purpose with GTAW and extending tungsten life especially at start up of the arc.  But how about SMAW, which came up in previous posts as to some of this young lady's questions about the purpose and application for all processes.

So, back to what I had asked in lite of her question and Obewan's comments, how does this assist with SMAW on these machines when it comes to the arc itself?  Or...does it?

Have a Great Day,  Brent
Parent - - By RonG (****) Date 02-01-2013 21:22
Brent, Kara; I could offer some experience in using Hi-Freq just to start SMAW. If that enters into the question, but I am unsure that is the question being posed.
Parent - - By welderbrent (*****) Date 02-02-2013 03:36
Break is over, has been for a couple weeks I just haven't gotten enough time to post. I have another although unrelated question.  GMAW has open circuit voltage, and I was just wondering since the gun has a trigger mechanism controlling the current if it would be at all possible or practical to use high frequency to start the arc.  And why is GTAW the only process, (that I am aware of) that uses super imposed high frequency to start the arc instead of open circuit voltage?  I realize it needs high frequency with ac but is that the only reason it uses high frequency instead of open circuit voltage?

This quote from her above post should answer that question Ron.  Her curiousity about the uses of HF want to know all aspects, applications, processes using it and why, etc are expressed and are reaching out to us for answers. 

So, GTAW is not the only process using HF.  For starting and/or running.  BUT, what are the reasons for it's usage?  We have seen that one, with GTAW, is to extend tungsten electrode life.  It also makes the arc initiation smoother, easier, cleaner.  Does it do the same when utilized with SMAW?  How about the effects of the HF portable SMAW machines previously mentioned? 

Now, I must admit, Kara has made me curious about this application.  But, I am mainly attempting to push this discussion on as I don't think we have totally answered her question yet. 

Please, any of you who have the knowledge to guide her, re-read the last few posts here and see what you can do.

Have a Great Day,  Brent
Parent - - By DaveBoyer (*****) Date 02-02-2013 04:25
HF start on SMAW helps get the arc started without the scratching & pecking to get electrical contact. This is a greater issue on restarts with rods that have flux protruding past the melted off end of the rod.

I have read & heard that it has been done, but the instructions on the HF boxes that I am familliar with caution against using HF with a regular SMAW electrode holder, as they are not insulated particularly well.

HF requires insulation designed for it, as the voltage is high, and power is "transmitted" like in radio broadcast due to the frequency.

This brings up a question for those who have used HF starting on SMAW: Did You use a special electrode holder ?

Brent, if there is still any question concerning the inverter DC welders, the high frequency is not present on the output. The high frequency allows an inductor to charge capacitors with high frequency pulses which generates less heat in the unit when compared to a transformer. Heat generated in the machine is just wasted energy.
Parent - - By Lawrence (*****) Date 02-02-2013 08:30
I have *NEVER* seen or heard anything about safely using superimposed high frequency in the SMAW process... Ever.

Could you imagine HF jumping out through every nick and thin spot on a SMAW work or stinger lead?  The HF may affect either or both dependent on polarity eh?

Could you imagine an SMAW electrode end with a blue HF foxfire continually radiating from it?    An arc striking every time the electrode end or stinger jaws were within an inch of something conducting to the work lead?

Never never never do this !

If anybody is considering trying this please don't.

This is not a technique you even want to experment with one time!

NO NO NO!
Parent - - By aevald (*****) Date 02-02-2013 22:57
Hello Lawrence, not to put a kink in all of the responses here regarding HF and SMAW but, Midstates produced an AC SMAW machine probably of late 50's to early 60's vintage that had an HF unit mounted on top of it. I owned one and ran quite a few different rods with it and in many ways it was pretty nice to use and work with. I also hooked up a dry-rig GTAW torch and did quite a bit of aluminum welding with it. It was a fixed amperage application, but you could still paste together quite a few things much better than some of the other alternatives. I have no idea as to the level of HF that it produced, although it was likely relatively low compared to newer versions and applications as they apply to todays GTAW systems. Best regards, Allan
Parent - - By Lawrence (*****) Date 02-02-2013 23:04
Pics... Pics...  

It sounds like those systems were deliberatly designed to do that...  Which has a big impact on safety eh?

No kink at all...  I suspected there would be some responses in the woodwork.
Parent - By ssbn727 (*****) Date 02-02-2013 23:13
That Arc Pig is a good high end additional tool for maintenance welding but IMHO, it doesn't pass muster for being applied to a situation where it would be used as part of a robust production system.

Respectfully,
Henry
Parent - By aevald (*****) Date 02-05-2013 01:23
Hello Lawrence, took some time to get back to this. I have long since sold the machine that I had and described in my post. However, I have included a link of a "newer" unit, likely based on the same sort of applications as the machine that I owned and containing similar circuitry. The machine in the link could provide AC welding with HF if you hooked up a GTAW torch and operated it on a fixed amperage. Definitely a poor-man's tig rig or well suited to Farm Code welding. Best regards, Allan

  http://yabe.chudov.com/Mid-States-180-AC-Welder/
Parent - - By ssbn727 (*****) Date 02-01-2013 23:27
When welding with the SMAW process, there's no need for HF - Period! So to answer your second question, the answer is it doesn't assist at all when compared to not using it with the SMAW process... So the last question is a resounding no... With that being said, My opinion with respect to your first batch of questions is this... Read the first sentence I wrote in this post because that's it!:eek::confused::roll::lol::wink::cool: Stop comparing apples with oranges in order to avoid confusion within this topic...

An excellent book to read over is: "Modern Welding Technology by the late, Truly Great Howard B. Cary, Past President of The American Welding Society, Welding Engineer/Consultant ... I've got the 4th edition and his explanation to this long running query is pretty elaborate and yet, it definitely clarifies the differences between arc welding with a non-consumable and a consumable electrode and the various nuances between the different welding processes involved... The ISBN # is: 0-13-241803-7.

Now, I've got a question for some folks in here beside Larry & Al... What type of components make up an inverter type power source? Btw, I already know the answer so please don't educate me... Just the facts folks! Just the facts.:eek::roll::wink::cool:

Respectfully,
Henry
Parent - By DaveBoyer (*****) Date 02-02-2013 03:53
Diodes, oscillator circuits, transitors, inductors, capacitors,  & magic smoke that MUST stay inside if it is going to work.
Parent - - By welderbrent (*****) Date 02-02-2013 04:18
Henry,  I don't think I am mixing apples with oranges.  Just trying to find some answers.  Kara said she doesn't get on the internet much, and we already know how questioning she is.  So, I am just trying to guide the discussion. 

Regarding Obewan's posts, the following one you agreed with, why are manufacturer's experimenting with SMAW usage for HF?  You say there is "no need".  That may be true.  That does not mean there is not an application.  Will it aid in initiating 7018 electrodes so there are fewer stuck electrodes (Obewan's suggestion in his following post)?  You say, "it doesn't assist at all when compared to not using it".  Yet, it is getting some attention.  And how would one know if it has not been experimented with?  That would have been a simple answer to aid in Kara's desire to know.  And you did give a reference.  Does he actually go into why HF is of no need or assistance with SMAW?

Sorry you feel that way Henry ("that's it").  I admit this is not an area of knowledge for me.  But I would like to see Lawrence's student find her answers.  I think answers can be given without being critical of the one asking the questions.  See, it isn't me...Kara asked, I just re-directed and expounded upon the answers with more questions that were basically hers in the first place. 

But, I am curious, as to your question, what does it matter in regards to any of Kara's question what the components are in an inverter type power source?  They may not be truly HF.  And that may not be your point.  But will that direct us at all toward an answer as to the application of HF to processes beyond GTAW?  (Again, Kara's question, not mine) 

But, I would rather see you take it out on me and rant on me instead of on this inquisitive young lady.  So, if this is so far below you and so petty of a topic with no purpose in expanding the science and knowledge of welding then do rant on against me.  But, please do it in private in a PM.  This thread does not need to be contaminated with ridicule, belittling, and demeaning.

Have a Great Day,  Brent
Parent - - By Lawrence (*****) Date 02-02-2013 08:34 Edited 02-02-2013 08:39
I believe  (Henry will Correct me if I'm wrong)

That Henry was discussing the High Frequency alternating current that is developed *WITHIN* an inverter power supply...    This phenomena allows the inverter power supply to be small and light...    Power supplied on aircraft for example is done this fashion.

I don't think Henry was discussing HF superimposed into the welding circuit of SMAW on DC or AC

I think the confusion in this part of the thread is due to a misunderstanding of this.

NO HIGH FREQUENCY on the business end...(work leads, stinger lead) of SMAW... NO no no

Let's please steer the discussion in another safer direcion.
Parent - - By ssbn727 (*****) Date 02-02-2013 12:57 Edited 02-02-2013 13:01
Thank you Larry for clearing that up for me!!!:wink::cool: I was referring to a comment from Brent regarding the high pitched noise emanating from a typical inverter power source which is basically HF being produced inside but, is not used as part of the welding circuit at all. In other words the components that make that noise are not directly part of welding output circuit so there's no super imposing going on there.

Brent, I'm sorry if you think that I was ridiculing you because in my mind at least, that wasn't my objective... In fact, I believe if that indeed was my intention I would have done a much better job than what you perceived to be a form of ridicule... Finally, to resonate even further on the use of HF with SMAW, Please do not try using this without first considering the safety precautions one must make before experimenting... In fact, as Larry also mentioned earlier, I don't recommend doing this at all... I hope Kara is reading this.

If there's too much flux over the tip of a low-hy electrode whether the electrode is new or already used, anyone can simply remove it with their properly covered other hand, or if one wants to get fancy, one can put a slight chamfer via belt grinder on the starting end of the the electrodes to be used in order to insure good starts prior to performing the actual welding therefore, there's no need for HF.:lol:

Finally, there are three processes that indeed use HF as part of their operation: #1 is GTAW, #2 is PAW, and #3 is Atomic Hydrogen although this process is hardly used anymore...

Pretty good Dave! What about a transformer, relays, cooling fans, thyristors, IGBT or MOSFET transistor banks, etc.... The magic smoke turns into that high pitched noise so, even that is converted for efficient use!!!:twisted::yell::lol::wink: Btw,if anyone didn't get that, it was a joke!:yell::wink::eek::roll::lol::cool:

That's my story and I'm sticking to it!!!

Respectfully,
Henry
Parent - - By welderbrent (*****) Date 02-02-2013 14:04 Edited 02-02-2013 14:12
Thanks for those replies guys, I need to make my apologies for being overly sensitive there.  There are no excuses for my bad reaction, just took it wrong and I should not have.  I also now note the many smilies and other emotion indicators you posted with it Henry.  :roll:

And thank you as well for some of the added information regarding this issue.  I find this to be very informative.  I had never considered it until some of the comments made led me to push the line of discussion that way.  I hope many, including Kara, have also found it informative.

How often do we go through our working routines without ever questioning these things and never knowing the why and how of the process.  And that added info most definitely did help my feeble mind to further understand how the process works better Henry.  Thank you.  And, thanks to Kara for asking the original question.  It did bring some good information and comments.

In other places during the course of this thread I have made reference to the Welding Handbook series with vol 1 'Welding Science & Technology' and vol 2 'Welding Processes' being of particular interest.  I was going to look at them more over this week end but ended up having to work.  The 3 hrs of driving each day with 10 hrs or more at the job site is starting to wear on me and my time to accomplish other things (like time with my wife who is also wearing out with me being gone).

One more thing, it is good to see you able to spend a little more time here Henry. 

Have a Great Day,  Brent
Parent - - By ssbn727 (*****) Date 02-02-2013 14:29
Hey Brent, It's okay buddy! Every thing's cool!

However, can you please do all of us who care about you a favor??? Please get some quality time and rest that very inquisitive & beautiful mind of yours okay?:lol::wink:

Slowly but surely, one day at a time Brent, I'm feeling a slight bit better and my overall condition is stable which is good enough for me, so thanks!

Respectfully,
Henry
Parent - - By welderbrent (*****) Date 02-02-2013 21:58
Just for your information (THREAD HIJACK!! :lol: )

To top off the hours, just before Christmas I got one of the bugs going around.  Nope, didn't take time off work.  In fact, the fabricator worked Monday, New Year's Eve.  And we have worked most Saturdays.  Plus, I have been getting back to Prescott and doing some welding at my shop there.

Between Christmas and New Year's I left early one day and went to the doc.  I had Bronchitis, Pneaumonia, sinus infection, and the coughing had ripped my larynx so I couldn't talk.  They gave me an inhaler, meds, but no special cough syrup because I am allergic to Codeine.  So I suck on Ricola Herbal cough drops like they are going out of style.  The flap of skin in the throat from the ripped larynx tickles the throat and makes you want to cough.  It also usually gets infected which slows down the healing.  I got it twice because the guys at the shop wouldn't stay home when they got sick either and the anti-biotics wiped out my immune system.  Both times I ran about a 103 temp for three days.

This has not been one of my better winters.  I am definitely run down.

But, I am working and enjoying it.  Thanks for the admonition to take care of myself.  I do need to watch it more.

Have a Great Day,  Brent
Parent - - By ssbn727 (*****) Date 02-02-2013 22:59
C'mon Brent!!!!

What??? Do you want to end up like me??? You better take better care of yourself brother!!!
Especially if you want to continue enjoying the work that's been coming your way because being on O2 24/7 is not fun at all!!! I can no longer go to the Y for a daily swim and when I can, it has to be supervised because of my handicap and this is all because I thought I was indestructible... Yeah Right!!!

So look where I'm at now and ask yourself if you'll be comfortable looking forward to what my life is now like if you don't want to prioritize your health as being unquestionably the number one priority on your list of things you MUST DO!!!

Seriously! Think about what I just told you, over, and over again if you have to, and let it ferment in your head enough so that it's the only thing you can think about because you really need to take better care of yourself, especially if you want to continue enjoying the times you have with your family!!!

I apologize if you think I'm being a bit harsh and yet if it were me and our circumstances were reversed, I would hope at least that you would tell me the same as a friend.:cool:

Respectfully,
Henry
Parent - By welderbrent (*****) Date 02-03-2013 00:37
Oh, I understand and appreciate your admonitions Henry.  I was like this when young and in recent years with things going well at the shop had stopped being like that.  BUT, this job is my first involvement with this particular inspections group and I am lead on the job and just let the responsibilities of work take priority over my health and family. 

Believe me, it was a hard lesson.  My exercises have slipped, time with the wife, kids, grandkids, etc.

But, I did have a great summer with my wife as last Aug was our 35th anniversary.  We went to HI, a family reunion in Lake Tahoe, and a trip to see my folks in OR in Sept.

Since then things have gone rather downhill.

But, thanks again and now.....back to the thread (end of HIJACK)

Have a Great Day,  Brent
Parent - By DaveBoyer (*****) Date 02-03-2013 03:11
Low power transformers for control circuits, high power transformers are NOT used, inductors take that place. Relays, possibly but why not use a transistor in the 21st century? IBGT and MOSFET are transistors. Yes, cooling fans keep that magic smoke inside longer.

Have You seen or used the Arc Pig ? I have only "seen" them on eBay, and another unit that looks the same but had a different name on it.
Parent - - By deisel (*) Date 02-02-2013 17:22
So inverters use high frequency as a power supply?
I knew from Larry that hf is impractical for smaw. I was wondering with gmaw though if hf could be used in place of open circuit voltage seeing as it has the trigger and the hf wouldn't constantly be jumping around at the electrode end like it would with smaw since there is no rheostat or trigger mechanism for smaw.
Parent - By Lawrence (*****) Date 02-02-2013 18:19 Edited 02-02-2013 18:25
No, HF in the weld circuit for GMAW (GMAWP is not part of this conversation)

The function of the inverter is to take AC current from the power company and turn it into welding circuit power... It does this in a different way than a transformer rectifier type power supply.... The short part of the explanation is that the inverter makes high frequency AC (inside the power supply) and changes it to whatever output is requred... For SMAW/GTAW that would be CC direct current... For GMAW/FCAW it would be CV direct current.

Read this Diesel
http://www.millerwelds.com/resources/articles/welding-inverters-decrease-maintenance-downtime/
Parent - - By OBEWAN (***) Date 02-01-2013 22:02 Edited 02-02-2013 01:08
I suppose there are others if you want to class an inverter as high frequency, but the arc frequency is not based upon a spark gap ocsillator like an old school TIG welder.  And, I forgot about SMAW welding.  My schooling predates Inverter technology, so I am just now getting up to speed regarding the details of their electrical theory.  We did use them at my last employer for manual and automated GTAW systems; but, I just used the technology and did not question the details.  I do have inverters on my reading "to do list" now.  I know there are several equipment suppliers now making "marketing claims" about new arc conditioning features for SMAW and GTAW.  We did not have this technology when I was in welding school; and I had occasional troubles with stuck electrodes for SMAW and GTAW when I was learning how to weld.  I was not certain at times whether it was my skill (or lack) or the machine capabilites.  LOL
Parent - - By ssbn727 (*****) Date 02-01-2013 23:43
I agree OBEWAN (Steve)! Back in the day, we didn't have any of these new-fangled inverter type power sources that are being produced nowadays and I also have been urged to try out the new arc conditioning features as well... Now I look at them with a healthy dose of skepticism because all types of claims have been made over the years, and while some of them have passed muster, there have been quite a few disappointments made over the years in claiming this or that only to find out that one could have achieved the same without the gadget that was bought and ended up as a paper weight on an office desk.:eek::roll::lol::wink::cool:

Respectfully,
Henry
Parent - - By RonG (****) Date 02-02-2013 04:55
To clarify my uncertainty on the Hi-Freq and SMAW issue. I have used Hi-Freq hundreds of times because our work almost always involves extremely expensive finished machined equipment. Clean starts are a must.

False or bad starts are simply not acceptable and as often as not we are working in a very confined space so we use a Fiberglass sleeve on the electrode to help prevent other mishaps.

But!  The Hi-Freq start is just that, and once the arc is established there is no Hi-Freq even with Inverter machines so I was not sure if it was worth mentioning.
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