PS
Calculating Full Hydraulic Steering Cylinder Displacement and Force
Specifications
Below is a chart to help with full hydraulic cylinder and steering valve selection. The
basic formula for figuring out how many turns lock to lock of your steering system is to
take the volume of the cylinder and divide it by the output displacement of the steering
valve.
C
volume of cylinder / cu in of orbital = turns lock to lock
example 25.82/7.6= 3.39 turns lock to lock
M
cylinder volume formula = piston area x stroke (note you must subtract the area or
volume that the rod displaces when figuing the volume of a cylinder on the rod side of
the cylinder)
area of a circle formula = 3.14(Pi) x radius squared
ot
example - a 1.75 bore cylinder has 1.75 diameter, which has a radius of .75 (diameter
divided in half = radius). 3.14 x .75 x .75 = a piston area of 1.766 You then multiply that
by your stroke to get displacement area or volume of your cylinder. 8 x 1.766 = 14.13
volume area
s
or
You also can take your piston area and muliply that by your pump pressure to figure the
force that the cylinder is able to produce.
pump Pres.
1500
1500
1500
1500
1500
1500
1500
1500
1500
1500
1500
rts
po
Steering Force
Bore shaft dia. length vol of cyl DE/ SE retract SE extend
1.5
0.625
6
8.14
2189
2649
1.5
0.625
8
11.68
2189
2649
1.75
0.75
6
10.89
2944
3606
1.75
0.75
8
15.70
2944
3606
2
1.25
6
9.03
2870
4710
2
1.25
8
15.31
2870
4710
2.25
1.25
6
14.03
4121
5961
2.25
1.25
8
21.98
4121
5961
2.5
1.5
6
15.31
4710
7359
2.5
1.5
8
25.12
4710
7359
2.5
1.5
10
34.93
4710
7359