Principle Of The Metal Inert Gas Welding Procedure; Functional Principle Of The Rehm Megapuls Welding Unit; Correct Use - REHM MEGAPULS 250 Betriebsanleitung

Introduction

1.2.2 Principle of the metal inert gas welding procedure

During the metal inert gas welding process the arc burns between a melting wire
electrode and the work piece. Argon, carbon dioxide (CO ) or a mix of these or other
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gases are used as inert gas.
The wire electrode is wound by a feed motor from a spool and pushed through the
torch package to the contact tip.
The positive pole of the current source is attached to the current contact tip, to the
wire electrode and the negative pole on the work piece. An arc is formed between
the wire electrode and the work piece which melts the wire electrode and fuses it to
the work piece. The electrode is thus arc carrier and welding material at the same
time.
The wire electrode and the pool crater are protected from the oxygen in the air by
the inert gas that is released from the nozzles arranged concentrically around the
electrode.
When pulse welding, the short high current phases mean that droplets are
transferred from the additional material without short circuits.
Dual pulse welding is a special form of pulse welding and enables a considerable
improvement of the weld due to the slope transfer.
1.2.3 Functional principle of the REHM MEGAPULS welding
unit
The REHM MEGAPULS 250 inert gas welding unit is a primary stepped, steplessly
adjustable constant voltage source for the MIG/MAG process. The MEGAPULS 250
is based on modern inverter technology with fully digital control enabling welding
results of the highest quality in MIG/MAG welding as well as in pulse and double
pulse welding, in particular for steel, aluminium and galvanised sheets. Post-
production work caused by spatters is reduced to a minimum and ensures a high
level of economy. The MEGAPULS 250 is innovative, robust and simple to use,
making it the ideal solution for all welding tasks which require a high degree of
precision and reproducibility of results. It is particularly well suited to meet the
professional requirements of trade and industry and the automotive industry. The
MEGAPULS 250 is noted for its reduced dimensions and weight, is easy to transport
and is a product which achieves the highest technological level under all working
conditions. With its flexibility of use the MEGAPULS meets an optimum performance
also when TIG welding with lift arc ignition and when electrode welding.

1.2.4 Correct use

REHM welding units are designed to weld various metals, for example, alloyed and
non-alloyed steels, stainless steels, aluminium and CuSi3. You should also pay
attention to the special regulations pertaining to your area of application. If anything
is unclear, consult your safety officer or contact REHM's customer service
department.
REHM welding units are, unless explicitly permitted in writing by REHM; only for sale
to commercial and industrial users and only for use by such. They may only be
operated by persons trained in the use and maintenance of welding units.
Welding current sources may not be set up in areas with increased electrical risk.
These operating instructions contain rules and guidelines for the correct use of your
unit. Only when these are adhered to can it be described as correct use. Risks and
damaged caused as a result of a different type of use is the responsibility of the
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