When rudder is on starboard 35 and then order is given to port 30 or 35, the variable discharge pump gets huge error signal gives maximum pumping rate but when it reaches 30 in port the error signal remains very less and it is much lesser than the error between 0 degree and 5 degree because when at 0 the error is maximum because floating lever link is at 90° to the radius. Again as the error between 30 and 35 is less, the pumping rate also becomes very less and at higher angles the travel of ram is more for each deg movement as compared to mid position. Moreover the feedback system on the steering gear gradually reduces the speed of the gear with in the last 5 degrees of the gears full rotation. If we put to 35 then the hunting gear will start to reduce the pump stroke and achieving this in a time frame of 28 sec will not be possible. So the test is done from 35° to 30°.
3 responses to “WHY RUDDER IS TESTED FROM 35 DEGREE ON ONE SIDE TO 30 DEGREE ON OTHER SIDE”
Why 28sec is necessary?
its a Solas requirement
THE RUDDER movement is limited to 35 degree – 30 degree angles when ship moving at max speed or normal speed ?