stayer MIG250CM Instructions D'emploi page 32

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GENERAL USAGE INSTRUCTIONS
SPECIFIC MMA WELDING INSTRUCTIONS
(COATED ELECTRODE)
In this type of electric arc welding, the electrode itself
produces heat through an electric arc due to the environment
protection, the improved electrode coating and the filler metal
of the electrode metallic soul merging while welding.
You must choose the adequate electrode (type and size)
according to the work you are going to do. The electrode we
recommend because of its medium characteristic, validity for
most of the works and easiness to find, is the E-6013. Better
known as "rutile electrode". The coated electrode welding
material par excellence is carbon steel.
After confirming all the security measurements and the
equipment inspection, cleaning, preparing and holding the
welding piece, the cords are connected according to the table
indications. For a casual use of the E-6013 electrode, the
negative polarity output (marked with a -) will be plugged to
the piece through the earth clamp. The positive polarity output
(marked with a +) will be plugged to the electrode holder
clamp, which will have the working electrode connected to
its bare extreme.
The welder must wear their individual protection equipment,
using mask or welding helmet, all adequate for working and
covering every inch of their skin to avoid radiation or welding
splashing. The arc priming welding will take place. There are
various procedures, being the piece scraping the simplest
one.
Once the arc is started, the electrode will be put at an
approximated distance equal as the same electrode diameter.
Then, the welding progress will start, pulling back as if an
Occidental right-handed person was writing.
The electrode must be kept in an almost vertical position
(65º to 80º), regarding to the horizontal one, and balanced
regarding to weld coating.
Depending on the pass type (filler or initial) and the union
coverage needs, keep going in a straight line, a zig-zag
movement or small circles. A good welding position, speed
and intensity adjustment will result in a nice and soft sound,
similar to the one of a good barbecue roast.
When a proper work is done, the resulting cord will be
homogeneous, with uniform half-moon surface marks. The
transversal profile will not be either protuberant nor collapsed.
The formed dirt will be easily removed.
Once the weld rod is done, you must remove the dirt with a
hammer before doing a possible following one.
Specific TIG welding instructions
In the electric arc made by protected tungsten electrode
through inert gas welding, the consumable material is not
the own electrode but a filler rode of a similar or compatible
material when welding.
In comparison with the coated electrode system, the TIG
system presents less productivity and a higher difficulty
but with a higher-quality welding on all metals and their
alloys, including all the stainless metals and situations of
low-thickness unions with or without filler. There is no dirt,
projections or smoke in the welding.
As a general rule, plug the output contrary to the usual TIG
torch electrode connexion to the negative terminal of the
equipment, while the earth clamp to the positive one. Prepare
and secure the piece. Adjust the current intensity according
to the material type necessities and the union to be made,
firstly trying it out on a testing piece. Refer to the tables and
specialized literature or to regulated professional qualification
for further information about it.
Inert gas should be provided to the torch (usually pure argon)
coming from a cylinder through a pressure reducer system.
It must be able to adequately regulate the necessary gas
flow. All the units need a TIG torch (not included – STAYER
references 38.71 and 38.73) with a direct connection to
the flowmeter and gas control through the gate valve,
incorporated in the TIG torch itself.
Once the arc is started, you now must proceed to execute
the welding according to its needs. As a general orientation,
you should keep going in a conversely way to the electrode
welding so that, instead of pulling it back, the focus will be
on the welding coating. Tilt the torch in order to focus it on
a very close vertical position (70º to 80º) with respect to the
horizontal and central one, regarding to the welding coating.
Slowly deposit the filling rod material, successively
approaching it to the fluxed material coating. To end, simply
calmly separate the torch until the arc is interrupted. Then,
close the manual gas gate valve. Lastly, close the inert gas
cylinder general valve.
Specific MIG/MAG wire welding instructions
The welding torch should keep a correct position for the gas
to conveniently protect the melting pool. Hold the torch with
both hands and try to get a fixed support point for a higher
cord stability.
It is recommendable an inclination, with respect to the vertical
one, of 10º. The free wire length will be contained between 8
and 20mm in order to get a better observation of the molten
pool and avoid the gas nozzle projections adherence. Avoid
working with airflows that may snatch the welding cord
technical gas.
Possible problems and solutions to MIG/MAG wire
welding:
INTERRUPTED THIN WELDING CORD
a ) Excessive wire progress speed
b ) Low gas output (begin with 5-7l/min and open the
manometer tap if necessary)
VERY HIGH WELDING CORD
a ) Very low wire progress speed
b ) Low welding current
UNSTABLE ARC – WELDING POROSITY
a ) Distant torch from the piece
b ) Dirty piece, with oil, grease, rust.
c ) Not enough gas flow. Check the gas regulator and cylinder
content
STUCK WELDED WIRE IN THE CONTACT TIP
a ) Very low wire progress speed
b ) Torch too close to the piece
c ) Momentaneous welding circuit interruption. Possible
causes:
1. Rusty contact tip
2. Wire progress mechanism difficulty
3. Wire and contact tip have different diameters
4. Damaged torch connection
5. Low pressure on wire progress
6. Tangled wire coil or normal wire progress stopped or
hindered due to wrongly placed wire
LACK OF WELDING PENETRATION
a ) Too high torch progress speed
b ) Low welding current
c ) Very low wire progress speed
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