Welding Mode; Mma Welded With Coated Electrode; Installation; Tig Welding - Platec Beast 250E Manual De Instrucciones

GB
10
POTENTIOMETER WELDING MODE
POT1
POT2
PULSED TIG
E1
12

WELDING MODE

12.1

MMA WELDED WITH COATED ELECTRODE

12.1.1
I
NSTALLATION
Connect the electrode holder and the earth clamp to the
output sockets of the machine according to the polarity
required by the manufacture of the electrode that you
wish to use.
CAUTION! Make sure that the electrode does not touch
any metal part at all, since in this welding mode, the
output sockets of the machine are live.
12.1.2 M W W
MA ELDED ITH
To obtain good welds, it is necessary to weld on clean
metal pieces, which
contaminating agents. In preparing the edges to be
welded, take into account the thickness, type of joint,
position of weld and the requirements of the project.
Normally the edges are prepared in a "V" shape; but with
thicker items, it is recommended to have "X" shaped
edges (backweld) or "U" shaped edges (no backweld).
The manufacturers of the electrodes specify the optimum
welding current for each type of electrode. The type of
electrode to be used depends on the thickness of the
material to be welded and on its position.
Insert the chosen electrode into the electrode holder. To
strike the electric arc, rub the electrode against the
material to be welded connected to the earth (ground)
clamp. Once the arc is struck, lift the electrode holder
slowly to the normal welding distance.
To strike the arc better, an initial current is supplied which
is higher (hot-start) compared to the welding current. The
electrode on melting deposits in the form of drops onto
the piece to be welded and its outer coating is consumed
supplying the shielding gas for the welding.
To facilitate the fluidity of the welding arc, while the drops
are coming off, which can cause a short circuit between
the electrode and the weld pool, a momentary increase in
the welding current (arc-force) is given, thus preventing
the arc from going out.
If the electrode stays stuck to the piece to be welded,
there is an anti-stick function that, after a certain short-
circuit time, cuts off the power to the generator. Thus you
can detach the electrode without damaging it.
When the coating electrodes are used, you need to
remove the dross from the welding after every pass.
General information for choosing the electrode are given
in the table below; we remind the operator that all data
are for the purpose of information only.
WELDING
PARAMETER
MMA Arc force
TIG Base current
MMA Hot-start
Frequency
MMA
Welding current
TIG
C E
OATED LECTRODE
are free of rust or
Cod.006.0001.0159_INVERTER_250E_2.2_17/11/2010_page_10_of_32
250E
MIN MAX
0 100
10 90
0 100
0,5 250
10 250
5 250
THICKNESS OF
MATERIAL (mm)
1,5 ÷ 3
3 ÷ 5
5 ÷ 12
>12
12.1.3

TIG WELDING

12.1.4
I
NSTALLATION
Connect the TIG torch to the negative socket, P1.
Connect the earth clamp to the positive socket, P2.
This model of welding machine has not been provided
either with the control for gas flow (solenoid valve) or with
the torch button.
12.1.5
T W
IG ELDING
other
In TIG (Tungsten Inert Gas) welding the electric arc is
struck between a non-consumable electrode (pure
tungsten or an alloy) and the workpiece in an atmosphere
protected by an inert gas (argon).
The TIG lift-arc process is struck by contact. A low short-
circuit welding current is set to limit the tungsten inclusion
on the workpiece. This process does not guarantee a
weld of high quality at the start of the bead.
TIG welding is used for welding that must have an
optimum finished appearance with limited post-welding
work.
This requires correct preparation and cleaning of the
edges to be welded.
The rods of consumable material must have mechanical
properties comparable to those of the material to be
welded.
The protection gas used may be pure argon, helium or a
mixture of argon and helium or argon and hydrogen,
whose quantities will vary according to the use.
12.1.6 P
D
IRECT
Pulsed current allows a better control of the weld bath
and ensures a restricted thermally changed zone, with
fewer deformations and less danger of gas inclusion and
hot cracking.
When the frequency increases, a more stable and
concentrated welding arc is obtained. This allows you to
get a higher quality weld on thinner materials.
12.1.7
I P
NVERSE
Inverse polarity, on the other hand, allows you to weld
alloys covered with a refractory oxide coating (whose
melting point is higher than the metal), e.g. aluminium
(and its alloys) and magnesium.
As opposed to direct polarity, here you attach the TIG
torch to the positive socket, P2, and the earth clamp to
the negative socket, P1.
um NOTES
% Percentage of welding current
% Percentage of welding current
% Percentage of welding current
Hz -
A -
A -
∅
WELDING CURRENT (A)
ELECTRODE
(mm)
2 40 ÷ 75
2,5 60 ÷ 110
3,25 95 ÷ 140
4 140 ÷ 190
W P C
OLARITY ITH ULSED URRENT
OLARITY