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MAX 503 IP54 - ATX
COD. 6913000050
6.0
6.0
6.0
6.0 ---- ELECTRODE WELDING (
ELECTRODE WELDING (
ELECTRODE WELDING (
ELECTRODE WELDING (MMA)
MMA)
MMA)
MMA)
6.1
6.1
6.1
6.1---- PROCEDURES AND
PROCEDURES AND
PROCEDURES AND
PROCEDURES AND TECHNICAL DATA FOR E
TECHNICAL DATA FOR E
TECHNICAL DATA FOR E
TECHNICAL DATA FOR ELECTRODE
LECTRODE
LECTRODE
LECTRODE
WELDING
WELDING
WELDING
WELDING
- Arc welding with coated electrodes is a procedure with which two metal parts are joined by
exploiting the heat generated by an electric arc which is sparked between a fusible electrode
and the material to be welded.
- Current generators for the electric arc (welding machines) may be fed with direct current or
alternating current; the former can weld any kind of electrode, while the latter can weld only
electrodes intended for alternating current.
- The constructive characteristic of these generators ensures an excellent degree of stability of
the arc even when its length varies as the electrode moves closer or farther away, due to the
movement of the welding operator’s hand.
- The electrode is composed of two fundamental parts:
a) the core, which is of the same material as the base (aluminium, iron, copper, stainless steel)
and has the function of inserting material in the join.
b) the coating, composed of various mineral and organic substances mixed together; its
functions are:
- Gas protection . A part of the coating, volatised at arc temperature, sends air away from the
welding zone, creating a column of ionised gas which protects the molten metal.
- Supply of bonding and scarifying elements. A part of the coating melts and supplies elements
to the weld pool which combine with the base material, forming slag.
- It may be said that the manner of melting and the characteristics of the deposit of each
electrode derive from the type of coating and from the core material.
- The principal types of coating are:
- Acid coatings. These coatings offer good weldability and may be used with either alternating
current or direct current, with the electrode gun connected to the negative pole (direct polarity).
The weld pool is very fluid, so electrodes with this coating are essentially suitable for welding
on a flat surface.
- Rutile coatings. These coatings give the weld seam an extremely good appearance, so they
are widely used . They can weld with either alternating current or direct current, with both
polarities.
- Basic coatings. These are used essentially for welds with a good mechanical quality, even
though the arc tends to splash and the appearance of the weld seam is inferior to that
produced with the rutile type. They are generally used with direct current, with the electrode on
the positive pole (inverse polarity), even though there are basic electrodes for alternating
current. Basic coatings are very greedy for humidity, so they must be kept in a dry place, in well
closed boxes.
It must also be remembered that steels with a carbon content of more than 0.6% must be
welded with special electrodes.
- Cellulose coatings. These are electrodes that weld with direct current, connected to the
positive pole; they are essentially used for welding pipes, on account of the viscosity of the pool
and the high degree of penetration. They need generators with suitable properties.
TECHNICAL
DESCRIPTION
ENGLISH
Summary of Contents for MAX 503 IP54-ATX
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