SPOT WELDING -
A resistance welding process in which fusion is produced by the heat
obtained from the resistance to the flow of electric current through the
workpieces held together under pressure by electrodes. The size and
shape of the individually formed welds are; limited by the size and
contour of the electrodes.
STRAIGHT POLARITY -
The arrangement of direct current arc-welding leads where the work
is the positive pole and the electrode is the negative pole of the
TACK WELD -
A weld made to hold parts of a weldment in proper alignment until the
final welds are made.
A localized fusion of metals produced by heating to suitable tempera-
tures. Pressure and/or filler metal may or may not be used. The filler
metal has a melting point approximately the same or below that of
the base metals, but always above 800° F (427° C).