Ultraflex UP25 F, Руководство по установке и обслуживанию

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PUMP FOR HYDRAULIC SYSTEMS
Installation and maintenance manual
1.2 Warnings for the correct product use
1 PRODUCT DESCRIPTION
1.1 Hydraulic steering system operation
UFLEX
steering systems must not be installed on race boats.
All
UFLEX
steering systems must not be installed on boats equipped with engines whose maximum horsepower
is higher than the horsepower rating approved by boat manufacturer.
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
WARNING
DANGER
l
engine
hydraulic hoses
cylinder
l
l
l
pump
The pumps UP25NV F and UP33NV F cannot be used with unbalanced cylinders and with double steering
system.
WARNING
All
UFLEX
hydraulic steering systems are designed in conformity with UNI-EN-ISO 10592 and A.B.Y.C. P21
regulations. All
UFLEX
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 located on the dashboard, 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 nonreturn
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 pumps series "NV" are not equipped with a
nonreturn valve so they cannot be used with two or more steering
systems. The cylinders are double-acting and they can be balanced
or unbalanced. In unbalanced cylinders the two chambers have
different volumes and therefore they require a different number of
steering wheel turns and a different steering wheel rotation effort with the same movement in the two
directions. The unbalanced cylinders cannot be used with the pumps series "NV". The balanced cylinders
require the same number of turns of the steering wheel to move the helm from the centre to the end of
stroke in the two opposed directions.
A well balanced steering system needs a correct choice of the pump for the cylinder.
UFLEX
produces different
pump models, which have different capacity (cm
3
of oil moved each steering wheel turn) and for each type of
installation. 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
3
[1,7cu.in.] and the cylinder has a volume of 120 cm
3
[7,3cu.in.], the
formula looks like this: 120/28=4,2. Accordingly, the steering wheel will turn about 4 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, also applications with more than 8 turns are not recommended, as the response
of the boat to steer is slowly.