Bosch Rexroth Tightening System 350 - Page 83

3 608 878 300 Tightening Technology | Bosch Rexroth AG 83/641
System 350 | 3 608 878 300/2019-03
Fig. 4–11: Power diagram for a 3-step tightening process
If a torque/power curve such as in Fig. 4–11 is assumed, the average power is calculated as follows:
Tightening:
Pre-tightening:
Final tightening:
The power loss can be calculated using table 4–14 as well as the following formulas.
Table 4–15: Formula abbreviations for the calculation of total power loss
Formula abbreviations:
TCycle time
P
G
Base load, according to the equipment
t
1
Tightening cycle time
t
2
Pre-tightening duration
t
3
Final tightening duration
P
1
Tightening power loss
P
2
Pre-tightening power loss
P
3
Final tightening power loss
n Number of channels
P
v
Power loss
Tightening Pre-tightening Final tighteningBase load
t
1
10
55min
1–
---------------------
60s
1min
-------------
10,9s==
P
1
P
1
6W==
P
2
P
2, max
P
2, min
–
2
--------------------------------------
P
2, min
+
419 W 0 W–
2
------------------------------------
0 W+ 210 W===
t
2
1
20 min
1–
-----------------------
60 s
1 min
--------------
 3 s==
t
3
0,5
20 min
1–
-----------------------
60 s
1 min
--------------
 1,5 s==
P
3
P
3, max
P
3, min
–
2
--------------------------------------
P
3, min
+
838 W 419 W–
2
-------------------------------------------
419 W+ 629 W== =