Q-factor monitoring
Q-factor (process stability / process quality)
The Q-factor is an indicator which expresses the stability or repeatability of the forming process
from stroke to stroke as a percentage number. A low Q-factor (e.g. less than 90%) would result
from a very unstable process where the forming force curves are changing significantly from stroke
to stroke. As a consequence, this would lead to fairly wide envelopes with little sensitivity.
Subsequently, this would also have an adverse effect on the consistency of parts quality.
Alternatively, a calm and stable process will produce high Q-readings of e.g. 95% or better
indicating the high degree of repeatability. Such a process can be monitored very closely with tight
envelope curves.
A separate Q-factor is being calculated for every sensor channel, and is shown as Q on the single
curve screen for this sensor. In addition, you can program a limit value QL which allows to set a
required minimum Q-reading. If the current Q-factor drops below your desired minimum
(e.g. because of an unstable forming process caused by poor material quality or other
inconsistencies), the machine can be stopped.
Calm and stable process with a high Q
Unstable process with a lower factor Q
How to set QL (Q-Limit)
- select the desired sensor chanel
- touch the field QL (field appears blue)
- set the new value vor QL
(compare picture above)
- if necessary correct the value by C
- confirm by E
SK 7
V5.2 E 10/04
SK7-18
