Page 180 - CITS - Welder - Trade Theory

WELDER - CITS

Causes Remedy
Excessive heat input. Use restraint (clamp) to hold base metal in position
Make tack welds along joint before starting welding
Improper weld technique
operation.
Select lower voltage range and/or reduce wire feed
Insufficient heat input.
speed.
Increase travel speed.
Weld in small segments and allow cooling between
welds.

Flux cored arc welding - Description, advantage, welding

wire for flux cored arc welding, types coding as per AWS

and specification- Trouble shooting in MIG welding.

Objectives: At the end of this lesson you shall be able to
• describe the flux cored arc welding
• explain the flux welding MIG wire.
• explain the flux cored wire specification.

Introduction
Flux Cored Arc Welding (FCAW) Fig.1 is an arc welding process in which the heat for welding is produced by an
arc established between the flux cored tubular consumable electrode wire and the work piece.

There are two major versions of the process, namely self shielded type (in which the flux performs all the functions
of shielding) and the ‘gas shielded type’, which requires additional gas shielding.
The gas shielded type FCAW is widely employed for welding of carbon steel, low alloy steel and stainless steel in
flat, horizontal and overhead positions.
However, the self shielded type FCAW is mainly used for carbon steel welding and the quality of weld produced
by this type is generally inferior to that of welds made with gas shielded type.
Equipment: The noticeable differences in the equipment used for GMAW and FCAW, are in the construction of
welding torch and feed rollers.

Fig 1

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CITS : C G & M - Welder - Lesson 49 - 60