GSK GSK988TA, Manual

Page: 131 / 531

Chapter 2 G Commands
113
Ⅰ
Programming
Surface speed=spindle speed× |X| × π ÷1000 (m/min)
Spindle speed: r/min
|X|: absolute value of X absolute coordinate value (diameter value) π≈ 3.14
Fig. 2-66
In G96, the spindle speed is changed along with the absolute value of programming path X
absolute coordinate value in the course of cutting feed (interpolation), but it is not changed in G00
because there is no actual cutting and is counted based on the surface speed of end point in the
program block.
In G96, Z coordinates axis of workpiece system must consist with the axes of spindle (rotary axis
of workpiece), otherwise, there is different between the actual surface speed and the defined one.
When the constant surface speed is valid, G50 Sxxxxx can limit max. spindle speed (r/min). The
actual spindle speed is the limit value of max. speed when the spindle speed counted by the surface
speed and X coordinate value is more than the max. spindle speed set by G50 Sxxxxx. After the
system powers on, max. spindle speed limit value is not defined and its function is invalid. Max.
spindle speed limit value defined by G50 Sxxxxx is reserved before it is defined again and its function
is valid in G96. Max. spindle speed defined by G50 Sxxxxx is invalid in G97 but its limit value is
reserved.
Note 1: G96, G97 are modal in the same group, and one of them is valid in the same time. G97 is initial word
and is valid after the system is turned on.
Note 2: In G96, S value executed is reserved in G97. there is no new S is executed and the S value in the last
G96 state is recovered to the current valid surface speed after the system returns to G96 state, the
system outputs the least surface speed in G96 when there is no saved value.
Note 3: From G96 to G97, if none of S code (r/min) is executed in the program block in G97, the last spindle
speed in G96 is taken as S code in G97, namely, the spindle speed is not changed at this time;
Note 4: The constant surface speed control function is still valid when the machine is locked(X, Z do not move
when the system executes X, Z motion codes);
Note 5: In G96, when the spindle speed counted by the cutting surface speed is more than max. speed of
current spindle gear, at this time, the spindle speed is limited to max. one of current spindle gear;
Note 6: In thread cutting, To gain the precise thread machining, it should not be adopted with the constant
surface speed control but the constant rotational speed (G97) in the course of thread cutting;
Note 7: No.3031 sets the numerical digit permitted by S.