Tolomatic User Guide:
IMA-S Integrated Motor Rod-Style Actuator - Stainless Steel
• 34 •
7:
R E P A I R A N D M A I N T E N A N C E
BALL SCREW LUBRICATION (Example Calculation)
Cycle Details:
Product: IMA-S 33 BN
V
RMS
: 1.66 in/sec
T
RMS
: 400 lbf
T
MAX
: 400 lbf
Step 1:
Calculate your actuator's power output.
P
IMA
= 1.66 in/sec • 400 lbf • 0.113 = 75
(watts)
Step 2:
Select the appropriate actuator power level.
P
C
P
C
= 105 = IMA-S 33 BN
Step 3:
Calculate the Power Factor.
K
P
=
105
= 1.4
75
Step 4:
The lubrication interval (
t
l
) for a given cycle is then calculated as:
t
l
= 9000
(hours) =
K
P
> 1
ROLLER SCREW
• For optimal performance and rated life, periodic re-lubrication is required.
100
1,000
10,000
100,000
1
0
2
3
4
Cycle RMS Velocity (in/sec)
Lubrication Inter
val (hrs)
5
6
7
8
Figure 6-3: Roller Screw Lubrication Interval Graph
Step 1:
Select the Basic Lubrication Interval (
t
BL
) based on the cycles RMS Velocity (
V
RMS
).
t
BL
= 4500 x (
V
RMS
)
-1.57
(hours)
Step 2:
Determine the Thrust Correction Factor (K
T
) based on the ratio of the
