Page 4 - Marine_EN

APPLICATION ACTUATORS

All over the world, goods are transported by ship or pipeline from the producer to the
consumer. To ensure safe loading and unloading, for example, ball valves are opened,
throttled or closed via a hydraulic rotary actuator. When used in explosion-hazard areas
such as on oil tankers, explosion-protected valves with corresponding certificates are
used.

FUNCTION
The rotary actuators of the ball valves are usually controlled
directly from the ship bridge or the command centre. In the
event of a power failure, the industry standard stipulates that
all ball valves must be completely closed via the accumula-
tor operation. So-called 3/2-way poppet valves are used for
a leakage-free hydraulic circuit, while 4/2- and 4/3-way spool
valves allow only an almost leakage-free hydraulic circuit.
On platforms that draw their energy from power generators,
valves with reduced power are mostly used. Especially with
valves in continuous operation, the power requirement can
be significantly reduced.

COMPONENTS
Screw-in cartridges or flange valves from the standard range

can often be used to control the rotary actuators. These are
available as leakage-free poppet valves or as low-leakage
directional spool valves in explosion-protected execution. In
order to meet special requirements or constructions, more
and more customer-specific valves are being developed and

adapted to the various rotary actuators.

SPECIALTIES

• Standard valves with customer-specific adaptations possible
• Available as standard or Ex-protection execution
• Valves with power reduction
• Valves in various corrosion protection classes up to K10

PAGE 2 | WANDFLUH MARINE | APPLICATION | ACTUATORS