| THE
SIMPLIFICATION OF
MIG & FLUX CORED WELD COSTS.
Followed
by
Metric Weld Conversion Data.
What's the actual weld cost per part?
WELD SHOPS AND GLOBAL WELD COST APATHY:
You may not want to walk into a welding shop, examine that very
common 1/4 (6 mm) MIG fillet weld and ask the shop manager or supervisor, what
does one foot (32 cm) of that 1/4 fillet weld cost?
Its
difficult in the global weld industry to find weld personnel that have control
and understand their weld costs.
I
doubt you will find that there is no more than one manufacturing manager in a
hundred,
that knows the weld deposition rate being achieved by the welders or robots they
walk by each day.
|
View
all MIG and flux cored programs at this site.
IT'S TIME FOR CHANGE:
In the world where managers and supervisors believe that welders
have to “play around”
with their weld controls, it’s not hard to understand
why many managers fail to understand the fundamental weld process correlation
between the welds, the MIG wire feed settings, the weld
deposition rates and the weld costs.
[]
WELD COST FACT: NO ONE USES MORE FLUX CORED WIRE THAN A SHIP YARD.
[]
WELD COST FACT: NO ONE HAS GREATER WELD REPAIR COSTS THAN
A SHIP YARD.
2007 WELD REALITY:
WITH WELD REWORK COST PER-SHIP TOO FREQUENTLY MEASURED IN
THE MILLIONS OF DOLLARS, LESS THAN THREE PERCENT OF GLOBAL SHIP YARDS
HAVE ESTABLISHED BEST WELD PRACTICES AND PROVIDED THEIR EMPLOYEES WITH MIG AND
FLUX CORED WELD PROCESS CONTROL TRAINING:
TAKE
A LOOK AT THE
MULTI-MILLION DOLLAR COST SAVINGS ONE USA SHIP YARD ATTAINED, USING ED'S UNIQUE
MIG AND FLUX CORED BEST WELD PRACTICES / PROCESS TRAINING PROGRAMS.
During
the first four months of 2007, Ed  and
Tom O'Malley presented one of Ed's weld  process
control training programs to Aker Kvaerner, an international ship Builder, located
at the the Philadelphia Naval Ship Yard.
The 300
plus welders in the yard used E71T-1 (1.2 mm) flux cored wires to weld
all position, vee groove, 12 to 25mm, steel joints with ceramic backing. Like
any ship yard the weld focus was always on skills training and skills capability.
All the welders had to pass the all position, flux cored weld qualification tests
and weld in accordance to the pre-qualified weld procedures. The weld rework costs
per-ship was measured in the millions. Many North American and European weld equipment
/ consumable vendors and weld engineers e were asked to resolve the numerous weld
issues, however the costly weld rework increased each year.
The
ship yard contracted with Ed to reduce the weld rework costs. After Ed established
the ground work for uniform Best Weld Practices with the weld equipment and consumables,
all the welders and supervisors in the yard participated in one of Ed's unique
Weld Process Control Training Programs.
The training program focussed
on flux cored Weld Process Controls,consumable knowledge
and optimum weld process techniques for all position, vee groove welds
with ceramic backing. In a time of welder shortage, when many companies find it
difficult to interrupt their daily productivity, management take note. Ed's unique
training program required only eight hours, four
hours classroom and four hours hands on. In a few weeks the training for the 300
plus welders was complete and the ship yard QA department started to analyze the
results..
 Three
months after Ed's process control the training, the ship yard NDT results indicated
a 50% reduction in the required weld rework per-ship.
The ship yard reported that the reduced weld rework, labor and NDT costs, had
so far resulted in a cost savings of
approx. 4.5 million dollars per-ship.
THE
COST BENEFITS FROM HIGH IMPACT, ONE DAY, CUSTOM TRAINING: Examine the real
world ship yard weld cost reduction and benefits for Ed's unique training program.
The training program required 300 x 8 man/hr. = 2400 man
hours at an approx. $30/hr, = base labor cost for the ship yard of $72,000.
To this add the actual training costs of approx. $100,000
= for a total training costs of approx. $172,000.
Savings,
four plus million dollars per-ship and training costs
less than $200,000. An unreported fact from this
yard was the changes that Ed established in the new weld procedure wire feed settings.
The increased flux cored wire feed rates, (weld deposition rates) increased the
daily weld productivity per-man in a range from 20 to 40%.
 Some
of you may wonder what's the difference between this type of weld training
program and the MIG and flux cored weld training you could expect in any North
American, Korean, Chinese, Japanese, European ship yard or any manufacturing facility?
Answer:
For decades conventional training in ship yards or manufacturing
plants has focussed on the welders skills. It's not
unusual for weld personnel to have weeks of hands on training and then find they
still play with the weld controls or utilize the weld controls
in a very limited manner. Most trained weld personnel lack process and
consumable expertise and this limits the weld quality and productivity potential
they could achieve.
The training I provided, as with all my training
programs, enables each individual to achieve flux
 cored
weld process optimization for the consumables and for the all position vee groove
applications. If the welder who took the eight 8 hour process control training
had limited skills, the ability to instantly set optimum parameters for the consumable
and weld joints provided instant dramatic improvements in their weld ability.
As you can see, on the left picture we have a weld made by an individual
with poor skills, poor techniques and poor settings. These two vertical up, vee
groove, weld samples using flux cored wires and CO2, were made by the same welder.
On the left before and on the right after the eight hours
of process control training. When the welder had good skills, this type
of training will increase the welders weld quality and productivity capability.
What was also important, each welder became aware of the unique parameters and
technique requirements for the variable gap root over the ceramic. The variable
parameter requirements for consistent side wall fusion on all the fill passes
and unique, uniform, parameter / technique requirements for the cap stringer passes.
The improvements by all the welders was immediately noticed
by the ship yard QA management who measured the dramatic improvements evident
with NDT and radiographs. The bottom line is of course the dramatic
four plus million dollars cost reduction which came from the reduction
in the required daily weld rework.
 By
the way, few global ship yards or manufacturing facilities examine the cost effectiveness
of the training programs they develop. Instead of an eight hour training program,
provide a forty hour welder training program for 300 welders in any North American
facility, and the minimal labor training and associated costs will be approx.
$500,000. Plus the facility will have lost 12000
production hours.
Many
thanks to the Aker Kvaerner
management for recognizing the training necessary
for their organization, and special thanks to Tom O'Malley the owner of Excell.
Tom's company is the prime weld products supplier to the Philadelphia Naval Ship
yard. Tom provided the facilities and equipment for the training. Tom also assisted
Ed with the program in both the classroom and for the hands on training. Tom is
one of those rare owners of a weld supply company that actually spends many hours
per-week evaluating weld processes equipment and consumables.
THERE
IS ONE WAY TO QUICKLY ATTAIN BEST WELD PRACTICES AND WELD PROCESS CONTROL EXPERTISE.
My
unique MIG and flux cored Best Weld Practices and Process Control training resources
are available in both book and CD form. I developed these materials over 30 years.
Ed's CD training programs,
 ROBOTS
AND WELD COSTS ....When a manufacturing company invests
in costly robots and fixtures, the robot purchase is in most instances intended
to reduce the costs of manual weld production”. The
sad reality is too many robot welds require extensive manual weld repairs.
The
prime factors that control the robot weld production efficiency potential are;
[1] optimizing the robot wire feed rates utilized,
[2] controlling
the part fit,
[3] controlling the weld size and length,
[3] optimizing
the robot movement / motion times,
[4] maintaining the robot arc on times,
[6]
eliminating the causes of the robot down time,
[7] the robot weld rework times.
The primary influence on robot weld efficiency
is the required robot “arc on time” a time regulated by the wire feed
rate attained. The wire feed rate controls the robot weld speed.
It's
unfortunate that some Japanese robots do not provide the robot wire feed rate.
These robots will have the robot programmer select "weld amps". I have
been in numerous Panasonic robot weld cells and the companies do not have a clue
as to the weld wire feed rates produced. So much for manufacturing and Japanese
focus on weld productivity.
To control MIG weld costs someone in the
plant has to understand the relationship between the desired welds, the weld wire
size, the wire feed rates and weld deposition attained. This process subject is
part of the fundamental weld process expertise that should be common knowledge
in all plants that MIG and flux cored weld. 
The
following book and training resources provides the process control data that all
engineers, managers, supervisors and technicians need to control
weld costs: 
ASK
A WELD SHOP MANAGER OR SUPERVISOR THE COST OF A MIG WELD AND THEY WILL TELL YOU
THEY DON'T KNOW, BUT THEY DO KNOW THE COST OF THE WELD WIRE
OR GAS.
Weld
process control knowledge is
the key component to implementing effective WELD BEST PRACTICES AND WELD PROCESS
CONTROLS, this sounds logical and yet few managers look for individuals that have
this process expertise.
To effectively manage a weld shop and maximize the daily robot weld quality and
productivity, management, supervisors and engineers must provide their employees
with a weld process control training program that provides;
[a]
PRODUCTIVITY: The weld process fundamentals that focus on the application's
weld deposition rate potential for the part thickness, weld size, wire size and
weld transfer mode utilized.
[b] QUALITY:
The weld process fundamentals required to attain "consistent" optimum
weld quality.
[c] EQUIPMENT / CONSUMABLES
COSTS: The weld process knowledge necessary to implement effective robot / manual
weld best practices. [D]
WELD CONTROLS: The weld process knowledge necessary to implement weld process
controls.
IT'S
HARD TO TALK ABOUT A SUBJECT YOU DON'T UNDERSTAND:
 This
week in the global weld industry, its unlikely you will find one manager in a
hundred who takes the time to have a discussion with their employees on how to
control the weld department costs.
The weld reality. Most weld
decision makers will show more concern for the costs of their weld consumables,
rather than on how to minimize their weld rework or maximize the weld deposition
rates.
While the focus is too often on
weld consumable costs, the MIG wire and gas typically account for only 12 to 15%
of the total cost of a MIG steel weld.
| 
He is a a weld supervisor, we have to
cut
out his "play around organ"
The
first step in controlling MIG weld costs
is
understand the wire feed control
 WITH
A TRADITIONAL "NONE DIGITAL" WIRE FEED CONTROL SIMPLY DIVIDE THE CONTROL
INTO TEN CLOCK SETTINGS BETWEEN 7 AND 5 O'CLOCK.
EACH WIRE FEED TURN
DELIVERS APPROXIMATELY 70 in./min PER WIRE FEED TURN.
WITH AN 0.035 (1mm) STEEL OR STAINLESS WIRE, EACH WIRE FEED TURN WILL
DELIVER 1.1 POUNDS PER TURN: SET THE WIRE FEED CONTROL AT THE FIFTH TURN THE 12
O'CLOCK POSITION AND THE WIRE FEEDER WILL DELIVER?
With the standard, ”none digital” wire feeder, set the typical spray
transfer wire feed setting of 3 o'clock position, (eighth turn). This wire feed
position with the 035 wire would deliver approximately 8.8 lbs/hr.
To set a digital or robot control with this spray transfer setting remember the
three o'clock position is the eighth turn 8 x 70 ipm = 560 ipm.
Check out
Ed's unique, simple weld clock process
control method on this web site or in his training resources or books. It’s
easy to teach because it’s easy to remember.
 ROBOTS
AND MANUAL WELD QUALITY: The number one controlling
factor of setting optimum quality MIG welds for any weld weld transfer mode is
to understand where you set the MIG wire feed setting and
to ensure that the wire feed setting is at the wire feed rate you set.
 ROBOTS
AND AND WELD COSTS: The number one method of controlling MIG weld costs is understanding
the wire feed setting and the weld deposition rate attained.
The majority
of welds produced daily in the industrial world are based on 3/16 - 1/4 - 5/16
(4 - 6 - 8 mm) fillet welds. Is it therefore reasonable that all the weld personnel
at your company should be aware of the wire feed settings and weld deposition
rate potential for the MIG and flux cored wire they daily use?
Ask
three of the most experienced weld personnel in your organization what the weld
deposition rate per/hr is that they are achieving on your most common welds and
watch the confusion in the replies. After three very different replies to a very
logical weld question, ask yourself when are you going to get serious about being
in the welding business and when are you going to arrange weld
process control training for your employees?
MY
PROCESS CONTROL BOOKS SIMPLIFY THE TASK OF ASSOCIATING
WIRE FEED SETTINGS WITH WELD WIRES / WELD SIZES AND WELD DEPOSITION RATES. USE
THESE BOOKS, OR MY ROBOT WELD PROCESS
CONTROL TRAINING PROGRAMS TO TAKE YOUR ORGANIZATION UP A NOTCH. THE PROCESS TRAINING
WILL ENSURE ALL YOUR WELD PERSONNEL ARE AWARE OF THE MANUAL OR ROBOT WELD DEPOSITION
RATES THEY SHOULD STRIVE FOR WHEN WELDING YOUR PARTS.
Weld
Cost 1
Weld Cost 1: THE
WELD DEPOSITION RATE: In the following example MIG welding
24 parts an hour, the parts are made out of 1/4 (6 mm) carbon steel parts. We
learn from the clock method that the weld deposition rate attained by the welder
to spray transfer the 1/4 fillet weld, using an 0.045 (1.2mm) wire, is
9
lb/hr (4.5kg/hr).
Weld
Cost 1:THE MIG WIRE COSTS:
If the manual MIG welders arc on
time per-hour is 20 minutes, the welder deposits 3 lb/hr. The carbon steel, MIG
wire cost IS $1 per/lb. The hourly MIG wire cost was $3
an hour.
Weld
Cost 1:THE
MIG WELD GAS COSTS: The
argon CO2 cylinder mix was $40.00 per-cylinder. A typical
full size gas cylinder will deliver on average approximately 300 cuft. The cylinder
gas cost is 13 cents per-cubic foot.
The MIG gas flow rate per/hour
is 30 cuft/hr. The welder average an arc on time of 20 minutes per hour results
in a gas use of 10 cuft/hr. 10 cuft x 13 cents = a MIG gas cost of $1.30
an hour. Weld
Cost 1:THE
MIG WELD LABOR COSTS: The average,
2007 hourly "welder's wage" in the US is $13 an hour, with benefits
it’s approx. $20 an hour.
Note; some companies when trying to evaluate welding costs, like to add the total
white collar overhead including the kitchen sink and the coffee machines on the
backs of the blue collar labor cost. In weld cost calculations this overhead is
an unnecessary distraction to the weld cost formula.
With an overhead
of $20 / hr, plus $3 / hr for wire and $1.30 hr for weld gas, the total hourly
cost per welder is $24 hour. Producing 3 lb/hr results
in a weld cost per pound of weld metal deposited at $8
per/lb. Producing 24 parts an hour, the weld cost
per-part is a $1.
HOW
TO REDUCE THOSE WELD COSTS.
Weld
Reality. An engineer, manager or supervisor
who had read one of my books would be aware that for the 1/4 (6 mm) fillet weld,
the welders could increase their wire feed control to readily attain a weld deposition
rate of 12 lb/hr (5.4 kg/hr).
The
25% an hour increase in weld deposition allowed 25% more parts per-hour from 24
to 30 parts. With the 12 lb, the 20-minute arc results in a weld deposition rate
of 4 lb/hr (1.8 kg/hr). The overhead costs are increased
by a dollar for the extra one pound of wire utilized. Labor, weld wire and gas
therefore cost $25 Divide this overhead by 4 lb/hr
= $6 lb. Divide the $25 by 30 parts and you have
approximately $0.83, a saving of 17 % per-part from
a simple single turn of the wire feed control.
FOCUS
ON WIRE FEED CONTROL FOR WELD COST CONTROL
|
AT 9 LB/HR | AT
12 LB/HR |
COST PER PARTS $1 |
COST PER
PART 0.083c |
A simple turn of the MIG wire feed control at most
weld shops can reduce by 15 to 20%.
|
WELD
CO$T FOCUS. A focus by management and supervision
on wire feed rates and the weld deposition rate potential
typically can reduce a companies daily weld costs from 15
to 50%. This is one good reason to think a little less about pulsed welding
and a little more about investing a few dollars for providing each welding individual
with a MIG process-training book.
KIS: To manage your weld costs, first I would recommend
you keep the training it simple. When evaluating weld costs, forget the costs
of white-collar overhead, forget the cost of the plant, the utilities, the manufacturing
equipment utilized or that Mercedes Benz sports car owned by the company VP. Simply
focus on the average total labor costs plus the benefits cost of the individuals
employed in the welding area.
Quoting
on this manual MIG weld trailer job was simple.
 Five
hundred trailers were required by the Smith Alloy Corporation. Each trailer had
a total of forty feet (12 m) of 1/4 (6mm) fillet weld. The MIG weld wire used
was an E70S-3. The wire size 0.045 (1.2 mm). The cylinder weld gas, argon - 10%
CO2.
The company that got the contract to build the trailers had five
MIG welders who each work an 8-hour day. The welder labor overhead was $25 an
hour. How long will it take to complete the job and what will be the welding cost?
 Using
my robot and manual MIG weld process control training books
this is how you would take 8 simple steps
to approach this task.
[1] How much MIG weld
wire is required? The 1/4 (6mm) fillet requires
0.11 lbs of weld per foot of weld. That's 0.11 x 40 feet = 4.4 lbs of filler metal
required per trailer x trailers = 2.200 pounds of
MIG wire for all the trailers.
[2]
How much will the weld wire cost?
The 0.045 filler
metal cost $0.90 cents / lb x 4.4 lbs/part = $3.96 weld wire costs per trailer,
or the wire cost for 500 trailers is $1980.00. [3]
How many man-hours are required?
Using my simple weld clock parameter method, you would be aware of where the welders
will have to set the 0.045 wire feed to weld the 6 mm fillet and that the weld
deposition rate would be approx., 12 lb/hr. However the manual arc on time per/hr
for the average welders is only 20 minutes. The welders deposited approximately
4 pounds per/hr. The 500 trailers will use 2200 pounds, divide by the 4 lb/hr,
the job will require
550 man hours. [4]
The weld gas costs, and how many cylinders required?
A cylinder of argon CO2 costs
$40 cyl. The cyl contains 330 cuft ($0.12 per cu/ft). The gas flow is 30 cuft/hr
but the welders arc on time is 20 min, so the gas used is only 10 cuft/hr x 0.12
cents = $1.20 / hr for the gas. The job requires 550 hrs x $1.20 = $660
for the gas, (550 hrs x 10 cuft = 5500 cuft divide by a cyl 330 cuft = 17-18
cylinders required for the project. [5]
The total weld consumables cost per trailer: The
cost of consumables for the job is weld wire, $1980, + gas $660, = $2640 divide
by 500 trailers or $5.28 per trailer. [6]
The labor cost per / trailer. The cost of
labor is 550 man hours required x $25/hr = $13.750.00 or labor per trailer $27.50. [7]
Total weld cost per trailer is
$5.28 for consumables + $27.50 for labor
= $32.78 per
trailer. [8]
The time required to weld all the parts. The time
required to do the job with 5 welders (40 hour / day). The job requires 550 man/hours
divide by 40 requires 14 days.
Ed
has a point. The bottom line, this weld cost approach is simple. Last time I saw
Miller, or was
it the Licoln or Hobart rep? I asked for a manual weld cost analysis, these guys
used a computer and delivered pages of confusing weld cost data. Now
I have finally got down to figuring out the real costs of the manual
MIG welds, I will see if we can do anything about weld cost reduction by using
robots.
For those individuals
making "weld cost decisions" consider Ed's process control training
programs for either MIG and flux cored or at least read "his
books. For
those interested in how the manual weld costs are reduced using a robot for welding
the 500 trailers, scroll down.
Quoting
this job with a Robot is made simple.
We will now quote the trailer
welds using a robot.
Each of the 500 trailers has forty feet (12 m) of 1/4 (6mm) fillet weld. We will
weld with an 0.045 (1.2 mm) MIG wire, and an argon - 10% CO2 cylinder mix.
We will use one robot with two operators. One robot operator works days,
the other is on the afternoon shift. The weld labor overhead is $25/hr. How long
will it take to complete the job and what's the welding cost per. How will it
compare to the above manual welding operation?
USING
THE EIGHT STEP METHOD: [1]
How much weld wire required?
A
1/4 6mm fillet requires 0.11 lbs per foot of weld x 40 feet = 4.4 lbs of filler
metal required per part x 500 = 2.200 lbs of MIG
wire required. [2]
How much will the weld wire cost?
The 0.045
filler metal cost $0.90 cents/lb x 4.4 lbs/part = $3.96 per part, or the wire
cost for 500 parts is $1980.00. [3]
How many robot / man hours required?
Using my clock parameter method you would know the robot
is set to deposit the 0.045 wire feed at a weld deposition rate of 12 lb/hr. However
in contrast to the manual welders, the robots weld faster and the arc on time
per / hr is increased to 40 minutes per-hour. With the increased arc on time the
robot deposits 8 pounds per / hr for two shifts. The two shifts (16 hrs a day
x 8 lbs / hr = 128 lbs per day). The 500 parts require 2200 pounds of weld metal,
divide by the 8 lb/hr deposited the job will require 275
man hours. (Its actually less when you look into the weld
speed benefits, I have got to save something for my process control weld books,
right).
For
the 500 welded parts, the robot with the increased arc on time will require <275
man hours. The manual welding job as discussed required 550 man hours for the
same application . |
[4] The robot gas costs and how many cylinders required?
A cylinder of argon - CO2 costs $40 cyl. The cylinder
contains 330 cuft ($0.12 per cu/foot). The gas flow is 30 cuft/hr, however the
robot's arc on time is 40 min, so the gas used is 20 cuft/hr x 0.12 cents = $2.40/
hr for the gas. The job requires 275 hrs x $2.40 = $660 for the gas. As the robot
weld speeds will be approx 20% quicker with the robot you can expect a 20% reduction
in the weld gas cost. Gas cost $528
[5]
The total consumable cost:
The cost of consumables for the job, MIG
wire $1980, + gas $528, = $2508 divide by 500 trailers or $5
per part. [6]
The labor cost per trailer.
The cost of labor is 275 robot / man x $25/hr = $6.875.00 or labor per trailer
is $13.75. [7]
Total weld cost per trailer.
$13.75 labor = $5 consumables = $18.75 [8]
The Costs.The
robot costs for welding the trailers was $6.875.00.
The manual labor costs for the same parts was $13.750.00.
The
total manual weld cost per trailer was $32.78.
Using a robot reduced
the weld cost to $18.75 per trailer.
|
:
 A
LOW COST, FAST SOLUTION TO YOUR ROBOT AND MANUAL WELD ISSUES.
Ed
whas resolved over 200 global companies weld issues on the phone.
If you
are having robot issues that affect your weld quality productivity or down time,
or if you want the best method and procedure for those manual welds, call Ed at
828 658 3574, (eastern standard time USA). The one day weld resolution fee is
$375 paid with Visa or MC.
Ed
will visit you facilty and provide hands on , instant solutions to all your robot
/ manual weld issues and a unique simple process control training program. In
one to three days you will experience dramatic improvements in your MIG and flux
cored weld quality and productivity.
|
HOW
DO I KNOW HOW MUCH WELDING
WIRE TO ORDER FOR A WELD JOB?
First determine the average fillet or groove
weld size. Use the following guidelines, and when you come to the final MIG weld
wire amount add 10% as a cushion factor. If you are going to use flux cored wires
add 20% to the MIG wire recommendations. For the metric users, 1 lb / ft of weld
to 1 kg/m, x by 1.488. The
following is the approximate amount of MIG filler metal required per foot of weld.
All the weld cost data you need for any MIG or FCAW application can be found in
my "Management Engineers Guide To MIG"
book.
CARBON
STEEL or STAINLESS WELD WIRE
REQUIRED PER FOOT OF WELD:
This
structural steel company wants to MIG weld 5 bridge structures. Each structure
has approximately 5000 feet of 1/4 fillet welds. The welders will use 0.045 MIG
wire. The manager wants a quick quote on the following. [a]
How much weld wire required? [b]
How much weld gas required? [c]
how many man hours to weld?
The above table tells you that a 1/4 6 mm fillet requires 0.11 lb/foot of weld.
5000 feet x 0.11 requires 550 pounds of weld metal. Add 15% for cushion factor.
Use my clock method to determine that the spray setting will deposit for this
application 12 lb/hr. Use the average arc on time of 20 minutes per/hr. The manual
MIG welder therefore deposits on average 4 lb/hr.
To deposit the 4 lb/hr
for the 550 lbs/ of weld will require 138 hrs of labor. You now know on average
a manual MIG weld uses 10 cuft.hr of gas x 138 hrs requires 1380 cuft add 15%
as a cushion 1587 cuft. Each gas cylinder requires approx 300 cuft of gas = 6
cylinders per unit.
WELD
COST REDUCTION WITH CLADDING ON
WATER WALL BOILER APPLICATIONS.
 
Ed's
contribution to the power and
waste management industry
2007:
Welding Services (WSI) is the largest contractor in North America and primarily
involved in repairs and refurbishment in the power, waste energy and nuclear industries.
In terms of water wall cladding, WSI has clad approx. 80% of the North American
boilers. Each year WSI uses hundreds of thousands of pounds of Inconel 625-622
and stainless MIG wires for cladding the water wall tubes.
While WSI has
produced some of the most innovative, automatic MIG cladding equipment available
in North America, WSI did not have a resident MIG process control expert who had
the expertise necessary to make radical improvements to it's water wall clad MIG
welds. Ed was contracted for this work by the WSI engineering manager. In less
than 6 months, as the following slides show, Ed not only dramatically improved
the water wall overlay weld quality but also reduced the
amount of overlay typically required by > 25%.
As many in the
power industry are aware, with any cladding application "less weld and less
heat provides the best results. Apart from the high cost of >$20 lb for the
Inconel weld wires, the boilers operate more efficiently when the clad surface
is thinner and the clad weld pass thickness is uniform.
With water wall
clad applications, the minimum, single pass weld clad chemistry required is 20%
Chrome. To attain the minimum Chrome requirements the pulsed MIG weld procedures
had to ensure the weld dilution was less than 8%.
The vertical down welds not only have to attain minimum weld dilution with consistent
weld fusion on the carbon steel boiler tubes. The weld passes I developed were
not only thinner they also supplied an improved transition with the weld pass
tie-ins. Of course from a weld productivity perspective, the two gun weld procedure
must be for a single operator deposit
> 26 lbs/hr.
A
typical cross section sample of an
"optimum water wall MIG clad weld.
The
variable weld clad thickness and uneven distribution
of welds from weld pass
to weld pass is typical.
MIG
Clad (vert down) with Inconel or stainless wires < 2006
With
global clad applications, due to lack of MIG weld process expertise and lack of
weld process controls, many stainless and Inconel overlay boiler welds have numerous
weld irregularities and will require extensive weld repairs.
The
poor clad weld quality will contribute to decreased
boiler life or require
premature weld repairs.
On
left, traditional clad method for vert down 622 overlay (as welded not cleaned).
On right Ed's first attempts at process improvements, again as welded not
cleaned.
 
Typical
Water Wall Boiler Tubes as used in the
Waste Management and Power Industry:
Ed's
first approach in 2005 to water wall clad welds.
An untouched sample of Inco
625 on water wall tubes.
After
approx. six months of weld process improvements.
The final 622 clad weld results
(top picture) developed by Ed in 2006.
Ed's MIG clad welds have
a smooth finish similar to a laser / powder overlay.
Bottom
picture. Old method and the field welds rarely looked that good.
Note:
All photos are untouched and no weld cleaning except brushing was provided.
With
Clad welds on boilers, less is always better,
unless you sell weld consumables. 
Tremendous
benefits were attained for the boiler
industry with Ed's new, "thinner"
single pass
MIG procedures developed in 2004 - 2005.
Weld
process expertise will always ensure that any
weld process utilized runs
without weld spatter.
2006: Ed's weld on the left,
typical clad welds on the right:
 The
vertical down 622 Inconel / stainless clad MIG welds were derived from a low cost,
six thousand dollar power source, a MIG gas mix developed by Ed. (See gas data
section). These welds required 28% less Inconel and stainless MIG wire per sq/foot.
. The welds also required an engineering manager that believed that there was
more to MIG welding than asking the advice of a Lincoln sales rep or pulling a
gun trigger. It also helped that WSI had excellent, well designed automated weld
equipment that compensated for the curves (wire stick out voltage variations)
when welding of the boiler tubes. Ed's clad development was complete in 2006.
WSI applied for the Patent during 2006.
THE METRIC WELD TABLES
Metric and Weld Deposition Rates.
Weld Deposition
Rates: = lb/hr x 0.4536 = kg/hr.
Weld Deposition Rates: = 1 lb/ft x 1.49 =
kg/m
Weld Deposition Rates: = Ib/in x 17.85 = kg/m.
Weld Deposition Rates:
= lb/min x 27.216 = kg/hr.
Weld Deposition Rates: kg/hr x 2.205 = lb/hr.
Metric and
Gas Flow Rates.
Flow
cuft x 28.317 = liters
Flow 0.47195 liter/min = 1 cuft/hr.
cuft x 1728
= cubic inch.
cuft x 0.02832 = cubic meter.
cuft/hr x 0.4719 = liters/min
cuft/min x 28.31 = liters/min.
liters/min x 2.119 = cuft/hr.
cu/meters/min
x 0.002119 = cuft/hr.
cuft x 7.4805 = gal US.
liters x 0.03531 = cuft.
gal/hr x 0.06309 = liter/min
gal/hr x 0.13368 = cuft/hr
gal/min x 8.0208
= cu/ft/hr.
gal/min x 3.785 = liter/min
gal x 3.785 = liter
liters/sec
x 127.13 =cuft/hr
Metric and
Thermal Conductivity.
Joules
Per inch = Volts x Amps x 60, Divide by weld speed ipm
Watt per meter kelvin
w/m.k
Heat input joules (j) energy J = watts/second
1 watt = 1 joule/sec
1 Kw/hr = 3,600,000
ft/ib = J x 1.356
1 joule = 0.73756 ft/ib.f
j/inch
x 39.37 = j/m
j/m x 0.0254 = j/inch
kj/inch x 39.37 = kj/m
Btu x 1054.4
= joules
btu/lb x 2.326 = kj/kg
cal/g x 4.1868 = kj/kg
Metric
and Fracture Toughness.
Metric Meganewton meter MN.m-3/2
ksi.in 1/2 x 1.099 = MN.m-3/2
MN.m-3/2 x 0.910 = ksi/in ½
Metric and Electrode Force.
Metric Newton = N
pound force x 4.448ton = newtons
kilogram force x 9.807 = newtons
newton
x 0.2248 = lbf
Metric and Area.
in/sq
x 645.2 = mm/sq
mm/sq x 0.001550 = in/sq
in/sq x 6.451 = cm/sq
ft/sq
x 0.09290 = m/sq
Metric and Speed.
ipm
x 0.4233 mm/sec
mm/sec x 2.362 = ipm
in/sec x 0.0254 = m/sec
ft/sec
x 0.3048 = m/sec
ft/hr x 0.00008466 m/sec
ft/min x 0.00508 = m/sec
km/hr x 0.027777 = m/sec
mph x 1.609 = km/h
cm/sec x 1.9685 = ft/min
cm/sec x 0.32808 = ft/sec
m/sec x 196.85 = ft/min
Metric and
Impact Strength.
Metric
= Joules = J
1 ft/lb = 1.355818 J
ft/lb x 0.13825728 = kg/m
Metric
and Volume.
cu/in
x 16.387 = cu/cm
cu/in x 0.00057870 = cuft
cu/in x 0.000016387 = cu/m
cuft x 0.02831 = cu/m
cu/in x 16390.0 = cu/m
cu/cm x 0.000035315 = cuft
cu/cm x 0.061024 = cu/inch
cu/cm x 0.00026417 = gal US
cu/m x 35,315 =
cuft
cu/m x 0.00061`024 = cu/inch
liquid gallon to cu/m x 0.003785
Weld
Current Density Electrode Area Square inch
Divide by Weld Amp
Weld current density metric = amp per square
millimeter = A/mm2
WIRE 0.030
area = 0.00071 in/sq
WIRE 0.8 mm area = 0.00458 cm/sq
WIRE 0.030 area
= 0.00071 in/sq
WIRE 0.035 area = 0.00096 in/sq
WIRE 1mm area = 0.006193
cm/sq
WIRE 0.045 area = 0.00160 in/sq
WIRE 1.2mm area = 0.1032 cm/sq
WIRE 0.062 area = 0.00307 in/sq
WIRE 1.6mm area = 0.0198 cm/sq
Metric and Length.
1 meter = 3.281 ft
1mm = 0.03937 inch
1inch x 25.4mm
mm x 0.03937 = inch
1 meter x 39.370
inch
ft x 304.8 = mm
mm x 0.003281 = ft
ft x 0.3048 = meter
yard
x 0.9144 = meter
Metric and Weight.
oz x 0.02834 = kg
lb x 0.4535 = kg
Short ton 2000 lb x 907 = kg
Long ton 2240 lb x 1016
= kg
Tensile strength x 1000 = ksi
Metric Megapascal MPa
I MPa = 145.03
psi
kPa = 0.14503 psi
psi = 0.00689 MPa
mpa x 0.145 = ksi.
Metric and
Pressure (psi).
Metric Kilopascal
kPa.
psi x 6894.575 = Pa
kPa x 0.1451 = psi
psi x 0.068948 = bar
psi x 6894.8 = newtons/sqm
1 psi = 0.0068 MPa
1 bar x 100000 = Pa
ksi x 6.894 = MPa
Pa x 0.000145 = psi
lb/sqft x 4.788 = Pa
N/sqmm
x 1000000 = Pa
Pa x 0.000145 = psi
Pa x 0.02089 = psi.
Pa x 0.02068
= lb/sqft
Pa x 0.000001 N/sqmm
bar = 14.5 psi
ksi x 6.894757 = MPa
psi x 0.006894 = MPa
DON'T FORGET, INVEST IN YOURSELF, CONSIDER MY WELD
BOOKS AS THEY WILL KEEP ON GIVING.
Visit
all the MIG and flux cored Best Weld Practices
and Weld Process Control Programs
at this Site.
E-Mail
Ed. ecraig@weldreality.com.
For phone or inhouse weld resolutions call
Ed at 828 658 3574.
Visit
Ed's Robot and Manual Process Control Training resources.
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metrc_weld_conversions | 
