Product Description; Hydraulic Steering System Operation; Warnings For The Correct Product Use - Ultraflex UC 69-1 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 equipped with a valve which prevents
outgoing fluid from returning along the same hose, allow 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 system needs a correct choice
of the pump for the cylinder. ULTRAFLEX produces different pump models,
which have different capacity (cm
While choosing 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 28 cm
the formula looks like this: 120/28=4,2. Accordingly, the steering wheel will turn 4,2 times 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, applications with more than 8 turns are also not recommended,
as the response of the boat to steer is slowly.
1.2 Warnings for the product correct use
DANGER
Do not modify the steering cylinder in any way to fit it to your 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
UC 69-I, UC 116-I, UC 168-I, UC 215-I and UC 293-I cylinders must not be installed on race boats.
WARNING
Cylinder UC 69-I can be installed on inboard engines up to 150 hp and only with single cylinder and single helm.
WARNING
All inboard cylinders can use standard KIT OB only if used with ULTRAFLEX UP Series hydraulic pumps whose
pressure relief valve (max pressure) is set at 70bar (1000PSI) while they must use KIT OB SVS if used with SVS
Series pumps or Master Drive systems.
NOTICE
Dual engine installations require the use of a tie bar.
Dual station installations require the use of 2 helms with non-return valve.
NOTICE
The maximum system torque must be calculated by the user according to the type of application used, the
helm number and features, the boat speed, the type of boat,etc.
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HYDRAULIC CYLINDERS FOR INBOARD ENGINES
of oil moved each steering wheel turn) and for each type of installation.
3
[1,7cu.in.] and the cylinder has a volume of 120 cm
3
Installation and Maintenance Manual
pump
l
l
l
hydraulic hose
l
cylinder
helm
[7,3cu.in.],
3