WÄRTSILÄ WARTSILA 20, Руководство по эксплуатации продукта

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Fig 17-2 Connection engine/two-bearing generator (4V64F0001B)
Dimensions [mm]
Engine
min D K L
D
1
130 140 150 120 W 4L20
160 180 190 150 W 6L20
160 180 190 150 W 8L20
160 180 190 150 W 9L20
17.2 Clutch
In many installations the propeller shaft can be separated from the diesel engine using a clutch.
The use of multiple plate hydraulically actuated clutches built into the reduction gear is
recommended.
A clutch is required when two or more engines are connected to the same driven machinery
such as a reduction gear.
To permit maintenance of a stopped engine clutches must be installed in twin screw vessels
which can operate on one shaft line only.
17.3 Shaft locking device
A shaft locking device should also be fitted to be able to secure the propeller shaft in position
so that wind milling is avoided. This is necessary because even an open hydraulic clutch can
transmit some torque. Wind milling at a low propeller speed (<10 rpm) can due to poor
lubrication cause excessive wear of the bearings.
The shaft locking device can be either a bracket and key or an easier to use brake disc with
calipers. In both cases a stiff and strong support to the ship’s construction must be provided.
To permit maintenance of a stopped engine clutches must be installed in twin screw vessels
which can operate on one shaft line only. A shaft locking device should also be fitted to be
able to secure the propeller shaft in position so that wind milling is avoided. This is necessary
because even an open hydraulic clutch can transmit some torque. Wind milling at a low
propeller speed (<10 rpm) can due to poor lubrication cause excessive wear of the bearings.
The shaft locking device can be either a bracket and key or an easier to use brake disc with
calipers. In both cases a stiff and strong support to the ship’s construction must be provided.
17-2 Wärtsilä 20 Product Guide - a13 - 6 September 2016
Wärtsilä 20 Product Guide 17. Power Transmission