Constant Surface Speed Control On/Off: G96/G97
Function and Purpose:-
This function controls automatically the spindle speed as the coordinates are changed during cutting in diametric direction so as to execute cutting by keeping constant the relative speed between tool tip and work piece.
Programming Format:-
G96 S__ P__ R__ ; Constant Surface Speed Control On
S = Axis for constant surface speed control
P = Surface speed
R = Spindle for constant surface speed control
G97 ; ………………….Constant Surface Speed Control OFF
Detailed Description:-
1. Axis for constant surface speed control is to be set by address P.
P1 : First axis
P2 : Second axis
X – Axis ( the first axis ) is automatically selected if argument p is omitted .
2. Spindle for constant surface speed control is to be set by address R.
R1: Turning Spindle for 1st chuck (left side chuck –upper turret or Right side chuck – lower turret)
R2: Turning spindle for 2nd chuck (Right side chuck –Lower turret or left side chuck –upper turret)
3. Control Change program and actual movement
G90 G96 G01 X20. Z50. S500 ; spindle Speed is controlled for a surface of 500 m/min
;
;
;
;
G97 G01 X20. Z50. F10. S500 ; Spindle Speed is controlled for 500 rpm
;
;
;
M02 ;
Notes:-
v The function is not effective for blocks of rapid motion (G00).
v The spindle speed calculated for the surface speed at the ending point is applied to the entire motion of a block of G00.
v The last value of S in the control mode of G96 is stored during cancellation of the control (G97) and automatically made valid upon resumption of the control Mode (G96).
Example:-
o G96 S500 ; 500 m/min or 500 Ft/min
o G97 S1000 ; 1000 rpm
o G96 X30.00 ; 500 m/min or 500 ft/min
v The constant surface speed control is effective even during machine Lock.
v Cancellation of the control mode G96 by a command of G97 without specification of S (revs/min) retains the spindle speed which has resulted at the end of the last spindle control I the G96 Mode.
Example:-
o G97 S500 ; 500 rpm
o G96 S350 ; 350 m/min or 350 ft/min
o G97 ; x Rpm
The speed X denotes the spindle speed of G96 mode at the end of the preceding block.
The constant surface speed control does not apply to the milling spindle.