Eaton Compressor & Fabrication C-STOV-MC001-E1 - Manual (Page 91)

EATON Char-Lynn Steering Catalog C-STOV-MC001-E1 July 2006 91
Sizing and
Application
Ackermann Type
Steering Continued
Differential Cylinder Cross Connected Cylinder
Balanced Cylinder Opposed Cylinder
D =
4A
+ d 2
D =
2A d 2
2
+
D =
4A
D =
D
4A
+ d 2
d
Note:
d
D
.15
2
( ) ( )
Step Two:
Force Required
F = T
r
F = Force required for the axle.
T = Kingpin torque as determined in Step 1.
The value calculated in Step 1 is the total torque for the
axle. If the steered axle is power driven, double this value
to approximate the additional dynamic loads.
r = Effective radius arm about the kingpin axis at which
the cylinder force is applied. The effective radius is the
minimum distance from kingpin to the axis of the cylinder
… not the actual length of the arm.
Cylinder Area
A = F
P
A = Cylinder area for the axle cylinder set.
F = Force
required
P = Hydraulic pressure
For vehicle with a steered axle that can never be overloaded
use 80% of the steering circuit relief valve setting. For
moderately loaded vehicles use 60%. For vehicles that can be
severely overloaded use 30%.
Cylinder Diameter
Once the required cylinder
set area is determined, the cylinder diameter can be calculated.
D = Inside diameter of cylinder.
d = Rod diameter as required.
Cylinder Stroke
S = Stroke Length
The cylinder stroke is determined by axle geometry. That is, the
required stroke is a function of the radius arm and the total
angle through which the arm turns.
d 2 V = S x
4
2D 2 — Cross Connected
Cylinder
d 2 V = S x
4
D 2 —
Differential Cylinder
(Small Volume or
Balanced Cylinder)
V = S x
4
x D 2
Differential Cylinder
(Large Volume)
Cylinder Volume V = Volume V = S x A
( ) ( )
( ) ( )
The volume of oil required to move cylinder rod(s) through
the entire stroke.