3.2
Operation Method of the Adjusting Device
The adjustable turbine nozzle ring is driven by two servomotors mounted on
the adjustment device. The motor speed is reduced and the torque
increased by means of a planetary gear unit. A Cardan joint transfers the tor-
que from the servomotor to the spindle drive. There is one spindle drive for
each servomotor.
In each spindle drive is a shaft with axial needle bearings. This shaft rotates
as the torque is applied. The rotational motion of the spindle shaft is con-
verted into a translational motion by means of a slotted nut.
The motion of the nuts of both spindle drives is transferred to the carriers
fastened to the setting ring, thereby inducing a rotational motion of the set-
ting ring.
There are setting levers evenly distributed around the circumference – one
setting lever per turbine guide vane – mounted in the setting ring. The setting
levers are positively connected to the turbine guide vanes, which are
mounted in the outer guide ring. The torque imparted by the setting ring to
the levers induces a rotational motion of the turbine guide vanes.
NOTE
For the adjustment of the turbine nozzle ring, the two servomo-
tors, operated in parallel, must be rotated in opposite directions.
Servomotors
(512.020)
Spindle drive
(511.001)
Setting ring
(510.003)
Adjustable
turbine guide vanes
2013-12-04 - de
3 Design
3.2 Operation Method of the Adjusting Device
MAN Diesel & Turbo
3
EN-US
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