As per SOLAS, Regulation 29 Steering gear
- Unless expressly provided otherwise, every ship shall be provided With a main steering gear and an auxiliary steering gear to the satisfaction of The administration. The main steering gear and the auxiliary steering gear Shall be so arranged that the failure of one of them will not render the other One inoperative.
- All the steering gear components and the rudder stock shall be of Sound and reliable construction to the satisfaction of the administration. Special consideration shall be given to the suitability of any essential Component which is not duplicated. Any such essential component shall, Where appropriate, utilize anti-friction bearings such as ball-bearings, roller-bearings or sleeve-bearings which shall be permanently lubricated or Provided with lubrication fittings.
- The design pressure for calculations to determine the scantlings of piping and other steering gear components subjected to internal hydraulic Pressure shall be at least 1.25 times the maximum working pressure to be Expected under the operational conditions , taking Into account any pressure which may exist in the low-pressure side of the System. At the discretion of the administration, fatigue criteria shall be Applied for the design of piping and components, taking into account Pulsating pressures due to dynamic loads
- Relief-valves shall be fitted to any part of the hydraulic system which Can be isolated and in which pressure can be generated from the power Source or from external forces. The setting of the relief valves shall not Exceed the design pressure. The valves shall be of adequate size and so Arranged as to avoid an undue rise in pressure above the design pressure.
- The main steering gear and rudder stock shall be:
- of adequate strength and capable of steering the ship at Maximum ahead service speed which shall be demonstrated;
- capable of putting the rudder over from 35 degree on one side to 35 degree On the other side with the ship at its deepest seagoing draught And running ahead at maximum ahead service speed and, under The same conditions, from 35 degree on either side to 3O degree on the other Side in not more than 28 seconds ;
- Operated by power where necessary to meet the requirements of a rudder stock of over 120 mm diameter in way of the tiller, Excluding strengthening for navigation in ice; and
- So designed that they will not be damaged at maximum astern Speed; however, this design requirement need not be proved by Trials at maximum astern speed and maximum rudder angle.