Product Description; Hydraulic Steering System Operation; Warnings For The Correct Product Use - Ultraflex UC 95-OBF Manuel D'installation Et D'entretien

ULTRAFLEX

1 PRODUCT DESCRIPTION

1.1 Hydraulic steering system operation

All ULTRAFLEX hydraulic steering systems are designed in conformity with UNI-EN-ISO 10592 and A.B.Y.C. P21
regulations. All ULTRAFLEX steering systems can operate at temperatures between -18°C (0°F) and +77°C (+170°F).
All the components are made for the marine environment, using materials and working processes which offer
long life and safety under the most extreme conditions. A hydraulic steering system consists of a steering pump,
a cylinder tied to the rudder or to the outboard or sterndrive engine and
the connecting hoses (see picture). Under normal operating conditions,
a turn of the steering wheel will pump the oil, which flows in through the
hoses to the cylinder, according to the turn direction. With the consequent
cylinder movement the oil will flow to the pump through the hoses and
at the same time moves the engine or the helm which are connected
to the cylinder. The pumps are equipped with a nonreturn valve, which
prevents outgoing fluid from returning along the same hose. It also allows
the operation of the steering systems with two or more steering stations.
The cylinders are double acting and may be balanced or unbalanced.
In the unbalanced cylinders the two chambers have different volumes
and so they need a different number of turns of the steering wheel and
a different rotation effort. The balanced cylinders have same number of
steering wheel turns in order to move the helm from the center to the
end stroke in the two opposite directions. A well balanced steering sys-
tem needs a correct choice of the pump for the cylinder. ULTRAFLEX produces different pump models, which have
different capacity (cm of oil moved each steering wheel turn) and for each type of installation. While choosing
3
the pump it is important to consider the cylinder volume. The number of starboard and port turns is determined
by the ratio between the cylinder volume and the pump capacity.
Example: if the pump has a capacity of 20 cm
formula looks like this: 94/20=4,7. Accordingly, the steering wheel will turn 4 times and an half before the cylinder
will completely turn from one side to the other. In case of installations with double cylinders connected in parallel
the cylinder volume must be added. Applications with less than 4 turns are not recommended, as they need a
higher effort, also applications with more than 8 turns are also not recommended, as the response of the boat
to steer is slowly. The maximum operating pressure is 7,0MPa (70 bar) (1000 PSI).

1.2 Warnings for the correct product use

WARNING
Before beginning the installation, check the mounting compatibility of the UC95-OBF cylinder to the engine by
consulting the attached document "Application Guide" contained in the packaging.
DANGER
Do not modify the steering cylinder in any way to fit it to your engine application, otherwise the cylinder will no
longer operate in safety and it will endanger the boat and the occupants.
WARNING
All ULTRAFLEX steering systems must not be installed on boats equipped with engines whose maximum horsepower
is higher than the horsepower rating approved by boat manufacturer.
WARNING
ULTRAFLEX hydraulic steering systems must not be installed on race boats.
DANGER
It is forbidden to disassemble the components which are supplied preassembled to avoid compromising the
product integrity.
[1,2cu.in.] and the cylinder has a volume of 94cm
3
HYDRAULIC CYLINDER FOR OUTBOARD ENGINE
Installation and Maintenance Manual
pump
engine
-
cylinder
h y d r a u l i c
hose
[5,7cu.in.], the
3
page 7
of 79