When performing roughing and other such operations during turning, these functions permit to command in a single block the machining program which is normally commanded in several blocks. In other words, they simplify the machining program. The following types of fixed cycles for turning are available.
G-code:-
G90 or G77 = Longitudinal Turning Cycle
G92 or G78 = Threading Cycle
G94 or G79 = Transverse Turning Cycle.
Programming Format:-
G90 X__ Z__ R__ F___ ;
Or
G77 X__ Z__ R__ F__ ;
Same for G92, G94
X = X cutting point
Z = Z turning length
R = Taper Value (Radial)
F = Feed Rate.
Longitudinal turning cycle G90 or G77:-
1. Straight turning
2. Taper turning
Threading cycle G92 or G78
1. Straight turning
2. Taper turning
Transverse turning cycle G94 or G79
1. Straight turning
2. Taper turning