Abstract:
In order to prevent distortion caused by heat which affects the material deformation, the
properties controlled are required. The properties changes and the placement of the mounting position
will effect the weld strength that causes cracks and broken joints, therefore it affects the safety of
machine construction. Thus, the objective of this paper is to control the shape of cross member
backbone assembly by gas metal arc welding (GMAW). The welding is produced by an automatic
robot Yaskawa-MA1440 type. In order to obtain the good quality of the result, the welding shape is
controlled by a parameters combination of voltage, current, and speed. Yaskawa-MA1440 type is
used as the automatic welding machine. The main material used is cold rolled steel coil sheet
MJSC270D-OD with a thickness of 1.2 mm. In addition, to control the welding shape, the specified
shape design standard is followed include travel speed, gas flow, welding direction, torch tip distance
to the workpiece, torch angle and welding angle. The results of visual and dimensional were also
examined in this research. Furthermore, the macrostructure i.e. leg length, fusion penetration, throat
thickness have been analyzed and confirmed based on the standards used in the auto body vehicle part
company. The appropriate parameters for the finest welding shape are defined at the horizontal
position using an electric current of 120 A and the welding voltage of 18 V (± 1 V). Thus, the
measurement control of macrostructure is defined as reference parameters for mass production of
cross member backbone assembly.
