Feedrate For Chamfer/Rounding Frc, Frcm - Siemens SINUMERIK 828D Function Manual

V1: Feedrates
17.4 Feedrate control
17.4.8

Feedrate for chamfer/rounding FRC, FRCM

General
The machining conditions can change significantly during surface transitions to chamfer/rounding. Hence, the
chamfer/rounding contour elements require dedicated, optimized feedrate values to achieve the desired surface
quality.
Function
You can program the feedrate for the chamfer/rounding with FRC (non-modal) or FRCM (modal).
The feedrate value is interpreted according to the type of feedrate active:
G94, G961, G971:
G95, G96, G97:
The FRC/FRCMvalue is applied depending upon the machine data:
MD20201 CHFRND_MODE_MASK
Bit 0 = 0:
Bit 1 = 0:
Reason: The feedrate type (G94,G95,G96,G961 etc.) and thus the conversion to the internal format must be
consistent within the block for F and FRC/FRCM.
Empty blocks
When chamfer or rounding is active, the possible number of blocks containing no traversing information is limited.
The maximum number is defined in machine data:
MD20200 CHFRND_MAXNUM_DUMMY_BLOCKS.
The possible blocks without traversing information in the compensation plane are pure dummy commands and
are called empty blocks. For this reason, they may only be written between two blocks with traversing
information.
Boundary conditions
• Feedrate interpolation FLIN and FCUB is not possible for chamfer/rounding.
• FRC/FRCM has no effect if a chamfer is being machined with G0; the command can be programmed according
to the F value without error message.
• FRC is only effective if a chamfer/rounding is programmed in the same block or if RNDM has been activated.
• FRC overwrites the F or FRCM value for chamfer/rounding in the current block.
• FRC/FRCM must be set to a value greater than zero.
1404
Feedrate in mm/min, inch/min or
Revolutional feedrate in mm/rev or inch/rev
FRC/FRCM from following block (default setting)
FRC/FRCM from preceding block (recommended setting)
o
/min
Function Manual, 09/2011, 6FC5397-0BP40-2BA0
Basic Functions