01/2018
60 / 80
6159933780
Issue no: 09
CVIL II
11 - TIGHTENING STRATEGY GUIDE
11.1 - Torque control
11.1.1 - Normal mode (continuous)
Torque control strategy is the most common use.
It offers the insurance that the torque has really been
applied to the assembly but doesn’t give the complete
insurance that the assembly is correctly done.
For example the parts could be not tighten enough or
not tighten at all when there is joint issues, i.e. "cross
threads", missing washer, broken bolt, larger size of bolt;
low quality bolt (even if the torque has been aplied by
the tool).
This strategy is selected when there is a wide angle
dispersion and consequently it is not possible to detect
the joint issues.
Some examples of joints:
● Drum washing machine
● Seat mechanism
● Outside rear mirors
● Cooling/heating components
Torque
Time
Target
Target torque
Search
sequence
Run down
speed
Final
speed
Run down torque
Max
Min
The recorded value is: peak torque
Spindle stop
● IF torque ≥ target torque
Accept report
● IF min. torque ≤ peak torque ≤ max. torque
Accept report with current monitoring (optional)
● IF min. torque ≤ peak torque ≤ max. torque
● AND min. current ≤ final current ≤ max. current
11.1.2 - Pulse mode (hybrid)
The "Torque control" strategy is effective only with joint
from 0° to 200°.
It offers the insurance that the torque has really been
applied to the assembly but does not give the complete
insurance that the assembly is correctly done.
For example, the parts could be not tighten enough or
not tighten at all when there are joint issues, i.e. "cross
threads", missing washer, broken bolt, larger size of bolt;
low quality bolt (even if the torque has been applied by
the tool).
Torque
Time
Target torque
Pulse threshold
Run down
torque
Target
Max
Min
Run down speed
Continuous
Pulse
Final speed
The recorded value is: peak torque
Spindle stop
● IF torque ≥ target torque
Accept report
● IF min. torque ≤ peak torque ≤ max. torque