
Next
time you consider paying $6000 to $12000 for that MIG power source,
keep in
mind that sound MIG welds can be made with
two car batteries
and a wire feed gun.
A
complete Pulsed MIG equipment package including the wire feed control is available
in North America in the price range of $4000 to $12500. What do you get for that
$8000 difference?
When
selecting MIG equipment for the weld shop, the weld shop decision maker has many
opportunities to throw good money out of the weld shop window.
<2007:
Pulsed has in the past two decades caused tremendous issues for shops that robot
weld common carbon steel and stainless applications.
After
years of painful, slow pulsed equipment development, I have found two pulsed MIG
power sources that can provide "limited" application weld benefits for
MIG welding carbon and stainless steel welds.
Most of the pulsed weld issues that are provided at this site are
not with the logical pulsed mode of weld transfer. The pulsed
issues are with the pulsed weld equipment manufactures who were responsible the
following.
[a]
Two decades of unqualified, exaggerated pulsed weld process hype that added to
the global weld shop confusion.
[b]
Providing faulty pulsed equipment to the welding market and providing no pulsed
product recalls. The bottom line is numerous, global weld shops were left with
erratic performing equipment that in many instances negatively affected both the
weld quality and productivity.
[c]
Weld equipment manufacturers who produced pulsed MIG equipment that is extremely
costly to repair and rarely made it through the product's warranty period.

Visit all the MIG and flux
cored programs at this site.
TO
LEARN FROM THE WELDING PAST, IS TO AVOID WELD MISTAKES AND THE WELD COST CONSEQUENCES
THAT WILL OCCUR IN THE FUTURE.
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1980s.
PULSED NORTH AMERICA:
MILLER ELECTRIC. THE INTRODUCTION
OF THE PULSEDSTAR PULSED MIG EQUIPMENT. THE BIRTH
PLACE OF NORTH AMERICAN PULSED BOVINE FECAL MATTER.
In
the nineteen eighties, the largest technical college in Vancouver Canada purchased
Miller's first pulsed MIG power source, the Miller "PulsedStar". This
pulsed equipment cost the college 300 to 400% more than a traditional CV. MIG
power source.
The Vancouver technical college was exited about it's
investment in new weld technology. For many weeks the instructors at the college
tried to get the Miller pulsed power source to produce a simple vertical up fillet
weld with an 0.045 (1.2mm) MIG steel wire on a 6 mm steel plate. All
position MIG weld capability was one of the prime features touted by the pulsed
MIG equipment manufacturers.
(Note:
Vertical up welds were not attainable from regular MIG equipment using spray transfer).
As the weld process control training manager for Linde, Western Canada,
I was considered an expert on the MIG process, I was also a strong advocate of
Miller welding equipmet. The Vancouver college asked if I would visit and see
what I could do with their costly pulsed MIG package. I was exited to work with
the so called new pulsed technology and scheduled a day to weld with the Miller
PulsedStar.
I set that PulsedStar power source at every possible wire feed,
voltage and pulsed frequency combination possible. The PulseStar simply could
not provide a suitable wire feed / pulsed parameter combination to MIG weld a
common "vertical up fillet" and to add
insult to injury, the pulsed welds made in the flat and horizontal weld positions
were vastly inferior to those made when the pulsed mode was switched off and the
traditional spray transfer was utilized.
For
many years after my introduction to the Pulsed Star I went around North America
turning the pulsed mode off and teaching the disgruntled Miller customers how
to set traditional spray and short circuit with this equipment.
It's
important for the reader to note, that in the nineteen eighties, up to the development
of pulsed MIG equipment, that without question Miller built some of the world's
best MIG equipment.
The Miller
Delta Weld product line, was for decades and still is my first choice for customers
who want the world's best performing, traditional, CV, MIG equipment.
AFTER
THE USELESS MILLER PULSEDSTAR THE UNSTABLE, FORGETTABLE PULSED MAXTRON FOLLOWED
: After the PulseStar came the pulsed Miller Maxtron. This unstable pulsed
MIG power source does not deserve one positive line in this web site.
WHO COULD ENVISION THE PROBLEMS
WITH THE THIRD PULSED POWER SOURCE FROM MILLER, THE INVISION:
After
the Miller Maxtron which provided no cost or quality weld benefits for carbon
steels or stainless welds, steel welds, Miller provided the pulsed Invision. This
power source went through more E-Prom changes than I have had pints of Guinness.
Finally the Miller Accupulse. If you used
this equipment on robot steel / stainless applications using pulsed and the adaptive
arc mode, you may have been getting arc instability, arc
ignition issues, arc outage or wire burn back issues to the contact tips. Many
of the pulsed adaptive arc issues that Miller had on their <2004 equipment
were similar issues they had on their pulsed equipment made a decade earlier.
2007: Keep in mind for the last two decades, pulsed MIG equipment was
typically sold to weld shops where traditional, low cost, none pulsed CV MIG equipment
was utilized. The approx. $2000 CV equipment provided great MIG and FCAW application
potential, good arc stability and for many weld shops the CV equipment lasted
ten to twenty years.
It's logical to wonder why the MIG equipment manufactures
you are loyal to, did not thoroughly test their pulsed MIG equipment before selling
it to your company.
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For
those weld shops that purchased pulsed MIG equipment before 2005 and noted arc
instability, (especially on robot welds) or short longevity, the MIG equipment
manufacturers are not likely to compensate you for their poor performing, over
priced MIG weld equipment. It's beneficial that all weld decision makers be aware
of the potential short falls and idiosyncrasies of the pulsed equipment purchased.





2003:
MILLER AND PULSED MIG DILEMMA.
A VP at a tier one supplier, asked that I analyze it's numerous weld process issues.
This company had purchased over 100 Miller Invision 11, Pulsed MIG units. The
MIG weld equipment was required for the companies new robot lines and manual weld
repair stations. After three months in production the shop found it had become
impossible to produce consistent, MIG weld quality. There was welding chaos at
the plant and the daily robot weld repair rate was over
60%.
The plant management team had no doubt what the cause of the
welding
problem
was, they had placed the responsibility for the weld issues on the shoulders shop
floor workers. After evaluating the weld issues, in my report I spelled out that
the majority of weld faults were not caused by the robots or workers. The
weld issues predominately were caused by the Miller weld equipment selected by
the management.
It's
a pity this tier one company management and engineers had minimal MIG weld process
expertise. These managers also did not understand the meaning of equipment ownership.
If the management had purchased Miller or Lincoln's "none pulsed" lower
cost, more durable, CV MIG equipment, they would have saved
the plant approx. $600,000,00 on the MIG equipment purchase and with a
little MIG weld process control training for the management, engineers and employees
they could have got their daily weld repair rate to less than
5%.
2005:
MILLER AND PULSED MIG DILEMMA.
In February 2005, I was
asked to assist a Canadian tier one auto supplier with it's automated steel welds.
The welds were made with the latest Miller Accupulse MIG equipment. Each part
required two simple yet critical welds that were only 20 to 25 mm in length. When
I examined the small welds two things stood out.
[1] Over 70% of the Accupulse weld length was a concave
smooth surface crater.
[2] In the middle of each weld crater was a
large pore and with many of the crater pores you could see without magnification
one or two cracks propagating into the crater.
The large weld
crater and large weld pore was strictly a result of the Accupulse equipment. Irrespective
of what weld data I placed into the ridiculous palm pilot weld control, the results
were the same, "a large crater with a large pore".
I worked for more than 10 hours to get rid of the crater and pore issues however
it was hopeless. Also there was no control for the MIG wire burn back and this
function was automatically controlled by the power source. I believe that the
power source delivered an excessive high voltage for the wire burn back and this
voltage resulted in the crater defects.
The Miller Accupulse crater
defects had gone on for months. Miller's response to the engineers at the auto
company was that the equipment was still in the Beta phase (they seem to provide
the Beta excuse for just about most MIG electronic power source they had built
between 1980 and 2000. The Miller solution to the serious weld defects was at
the end of the weld re-strike the arc.
However due to limitations in the automated equipment and PLC controls
there was no way to re-strike the arc. FOR FOUR YEARS, the Canadian auto company
produced parts in which the small length welds had more crater than weld and the
majority of the welds had cracks. Many of the parts welded would eventually lead
to failure, however as they were only American car parts, who gives a dam.
There
were grave cost consequences for the weld issues generatyed at the plant.
The apathetic weld management at the plant could have readily sued Miller. However
to sue a company over weld issues, you need management and engineers who understand
and can prove the root cause for their daily weld issues. You won't find many
too managers or engineers in the auto / truck industry that have this fundamental
weld process expertise.
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HOW
PULSED MIG EQUIPMENT
INFLUENCED MY CAREER: