Stiga Park Series Workshop Manual page 41

Edition Manual
2014-03-31 Workshop Manual, GGP Park 3 Steering
machine. This is particularly noticeable during
cold weather.
Mainly, the hydraulic assisted system works
similar to the mechanical system. The different
is a torque booster (D), atttached to the steering
shaft between the steering wheel and the
sprocket (A).
A oil flow from the HST is flowing through the
torque booster via a filter.
As the driver turns the steering wheel, there
occour a pressure drop over the torque booster.
The pressure drop, multiplied with the flow,
gives a moment (Ma), which is added to the
moment from the driver (Md) and applied on the
sprocket (A) as a moment (Ms).
The following items are shown in the figure:
A Sprocket of driving the steering chain.
D Torque booster.
Mh Steering power (moment) from the
hydraulic transmision.
Md Hand power (moment) from the driver.
Ms The sum of Ma and Md as steering power
(moment on sprocket A).
Hydraul connections
The hydraul lines have two alternative
connections:
• Pressure plate with O-rings around the tubes.
• Banjo fitting.
Pressure plate
Always mount new O-rings when assembling.
Banjo fitting
The connection have no gaskets.
Always tighten the nipples with 70 Nm when
assembling. See the figure.
Chapter
70 Nm
A
Ms
Md+Mh=Ms
Page
Md
D
70 Nm
Mh
3