Page 384 - Lewmar

9. Steering

Rotary Sprocket Drives – To suit Constellation™ & Mamba™

Lewmar offer 3 sizes of powerful and compact rotary drive units, which employ conventional chain and sprocket connection to
the steering system.
The high-effi ciency, twin-stage, epicyclic gearbox is grease fi lled, which allows mounting in any attitude. The wide mounting
platform is slotted to aid chain tensioning. Rotary drives are generally used on cable and push-pull steering systems and it is
necessary to calculate the correct driven sprocket, which is dependent on the turns (mechanical advantage) of the steering
system.

Lewmar can supply fully machined sprockets for your steering system in steel or stainless steel upon request, as well as chain
and master links.

Please refer to the graph to calculate the correct sprocket
size. The turns lock to lock is referred to at the position on
the steering where the driven sprocket is to be mounted.

Turns Lock to Lock Steering system

Sprocket Ratio

MAX OUTPUT NO LOAD MAX RUDDER AVGE CURRENT
POWER VOLTAGE TORQUE SPEED TORQUE CONSUMPTION WEIGHT
    .  RPM  .   
⁄ "    ⁄ .  . .
⁄ "    ⁄ .  . .
⁄ "    ⁄ .  . .
/ "    .  . .
   

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