REHM MEGAPULS 250 Betriebsanleitung Seite 89

Operation
MIG/MAG welding
torch
Torch-
equipment
Wire feed spirals
Wire feed setting
The required amount of inert gas will depend on the wire diameter, the size of
the gas nozzle, the level of current used and the movement of air within the work
place. The required volume of gas for mixed gases is approx. 7... 16 l/min, for
Argon approx. 10 ... 18 l/min.
Rough formula for estimating gas settings:
For steel: Wire diameter x 10
For stainless steel: Wire diameter x 11
For aluminium: Wire diameter x 12
The gas-cooled MIG/MAG torches recommended by REHM are to be connected
to the REHM MEGAPULS 250 unit. Water-cooled torches can only be used in
conjunction with a REHM water cooling unit.
The accessories selected for the torch will depend on the welding task in hand
and must be chosen to suit.
Contact tips
Contact tips are consumable parts and must be replaced from time to time. You
should ensure that the contact tips are selected to suit the wire diameter you are
using.
Special contact tips are available for aluminium welding tasks, these are
available in various wire diameters and can be found in the REHM welding
accessory catalogue.
Gas nozzles
Gas nozzles are available in various forms and can be found in the REHM
welding accessory catalogue
Wire feed spirals must be selected in accordance with the material type and wire
thickness used. The range can be found in the REHM welding accessory
catalogue
The notes given by the torch manufacturer should also be taken into account
(see instructions).
The following information must be taken into account in order to ensure secure
wire feeding:
Feed rollers must be selected to match the wire diameter.
Secure wire feeding is ensured by the 4-roller system.
You must ensure that the pressure on the wire exerted by the feeder rollers is set
correctly. When using aluminium the pressure should be as low as possible but
still permit safe transportation of the wire. When using steel and stainless steel,
the pressure should be such that the wire spool can still be halted by hand even
during operation.
CAUTION: When welding the side panel which protects the wire feed area from
access must be closed in order to prevent injury (e.g. bruising).
The wire feed rate must be set in such a way as to ensure a smooth and stable
arc. When increasing the welding energy, the wire feed rate increases
automatically and can be corrected, if necessary, using the wire feed rate
correction knob.
= Amount of gas in litres.
= Amount of gas in litres.
= Amount of gas in litres.
GB
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