Clarke MIG220TE, Operating & Maintenance Instructions

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MIG WELDING - PRINCIPLES OF OPERATION
MIG (Metal Inert Gas) welding is a process in which a power wire electrode is fed continuously
into the weld pool at a controlled, constant rate. The wire is connected to the positive side of a
rectified voltage supply. The workpiece is connected to the negative side of the supply. When the
wire is fed, it comes into contact with the workpiece and an arc is struck. The arc melts the wire
and the material, fusing it together. The wire, which is fed by the wire feed motor is fed into the
weld pool, burning itself off at a rate dependent upon the selected wire feed speed. To protect the
weld pool from oxidation and impurities during the welding process, a shielding gas flows over
and around the weld pool. This gas flow must be sufficient to protect the weld, but not be
wasteful.
NOTE: Poor gas coverage will result in poor welding. Excessive gas coverage is
wasteful and expensive
.
BENEFITS OF MIG WELDING
• 50% faster welding time.
• Operator training time kept to a minimum.
• There is no slag removal, thus eliminating almost all post-welding
cleaning operations.
• Minimum waste of welding consumables.
• Overall, a faster more efficient way of getting the job done.
• Less heat - less distortion.
• Ability to weld thin material.
DECLARATION OF CONFORMITY
We declare that this product complies with the following standards/directives
•
93/68 EEC
•
89/336 EEC
•
73/23 EEC
•
98/37 EC
•
EN50 119
•
EN 60 974-1
Signed
L.E. Fergusson
Engineering Manager