Georges Renault CVIS II, Руководство оператора

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TIGHTENING STRATEGIES
7 - STALL TORQUE CONTROLLED TIGHTENING
The recorded values are the following: final torque and final angle
Spindle stop
IF
stall time elapsed
OR torque > max. torque
OR angle > max. angle
Accept report
IF
min. torque
≤
final torque
≤
max. torque
IF min. angle
≤
final angle
≤
max. angle
8 - PREVAILING TORQUE CONTROLLED TIGHTENING
The recorded values are the following: mean torque, minimum torque read and maximum torque read.
This tightening strategy is used to check the tuning of a tightening
unit in static mode with the possibility of monitoring the linearity
of its torque transducer.
The stall torque tightening is also used when you want to keep a
constant torque on a joint, either to compensate a creep in a seal,
or to keep a load on a joint during a complex operation. During this
phase, as long as the motor has not reached its torque value, the
motor is controlled on the speed loop. When the stall torque is
reached, the torque control and stall are performed on the current
loop. The stall time can be set between 0.1 and 10 seconds.To
avoid the overheating of the motor, in this type of application it is
recommended to oversize the tightening unit.
The thermal contact located in the motor provides protection in
case of overheating.
The max. torque must be programmed to a value higher than the
desired stall torque.
This phase allows you to check the residual torque (prevailing
torque) of a mechanical assembly.
Examples of mechanical assemblies: gearbox, crankcase, etc.
This phase is useful to know if there is a mechanical "hard"
spot in the assembly and also to detect the absence of a
component in the joint (crankshaft or connecting rod bearing
shell, gear, control of the friction torque of a Nylstop nut)
when the residual torque is higher than the min. torque.
Two types of monitoring are available, according to an angle
or to a torque
1 Prevailing torque monitoring, with time- or angle-
controlled stop:
The initial timeout (threshold), expressed in time or angle
units, allows you to eliminate the "shock" when starting the
motor and the mechanism.The memorised result includes the
minimum and maximum values and the mean of the torque
measurements during the acquisition phase. The system stops
the acquisition of the torque and angle when the motor stops.
The torque pulse at the motor stop is not taken into account.
T o r q u e
S t a l l t i m e
M a x i
A n g l e
t h r e s h o l d
T i m e
F i n a l a n g l e
S t a l l t o r q u e
Angle
Time
Rise-delay
time
Data
acquisition
safety
Max
target angle
Min
Torque
mean
torque