Siemens SINUMERIK Series

W4: Grinding-specific tool offset and tool monitoring
17.5 Constant grinding wheel peripheral speed (GWPS).
Extended Functions
Function Manual, 03/2013, 6FC5397-1BP40-3BA1
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17.5 Constant grinding wheel peripheral speed (GWPS).
17.5.1 General information
What is GWPS?
A grinding wheel peripheral speed, as opposed to a spindle speed, is generally programmed
for grinding wheels. This variable is determined by the technological process (e.g. grinding
wheel characteristics, material pairing). The speed is then calculated from the programmed
value and the current wheel radius.
Note
GWPS can be selected for grinding tools (types 400- 499).
Speed calculation
The formula for calculating the speed is as follows:
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*:3
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Note
Grinding wheel peripheral speed can be programmed and selected for grinding tools (types
400- 499).
The wear is considered when calculating the radius (parameter $TC_TPG9).
This function also applies to inclined wheels/axes.
The associated wear and the base dimension as a function of the tool type are added to the
parameter selected by $TC_TPG9.
The sum total is divided by "cos" ($TC_TPG8) when the value of parameter $TC_TPG8
(angle of inclined wheel) is positive, and is divided by "sin" ($TC_TPG8) when the value is
negative.
When is the speed recalculated?
The speed is recalculated in response to the following events:
● GWPS programming
● Change in the online offset values (wear parameters).