ISO 13929 pdf download.Small craft — Steering gear — Geared link systems
1 Scope
This International Standard specifies the minimum level of requirements for construction, operation and installation of geared link steering systems on all types of small craft of hull length up to 24 m. It excludes steering systems covered by ISO 8848 and ISO 9775.
2 Terms and definitions
For the purposes of this International Standard, the following terms and definitions apply. 2.1 geared link system system in which rotation of the steering wheel positions the rudder blade by means of gearboxes, which converts the rotary motion to a push/pull force on the rudder operating lever, via a draglink assembly 2.2 draglink component linking the rack operating lever to the rudder operating lever, which transmits the push and pull forces and allows rotational and angular misalignment 2.3 rudder operating lever component fixed to the rudder, transmitting the torque to the rudder shaft from the steering system 2.4 rack operating lever component fixed to the shaft of a steering system which rotates in relationship to movement of the steering wheel and achieves a corresponding movement of the rudder operating lever via the draglink 2.5 maximum output force force that the system can supply upon application of a 450 N force tangentially to the wheel
4 Constructional requirements
4.1 General 4.1.1 Steering rating The steering system type shall be rated according to both its maximum permissible output torque and the corresponding rudder torques produced both at rudder midships and full lock. The manufacturer’s specification for the maximum permissible output torque shall be used to determine the tangential torque tests as specified in 6.3. 4.1.2 Fasteners All threaded fasteners whose integrity affects safe operation of the steering system shall be provided with a means for locking. 4.1.3 Materials The choice and combination of materials shall be such as to minimize the risk of corrosion and galvanic action. 4.2 Specific 4.2.1 Rudder angle The steering system manufacturer shall specify the maximum rudder angle. 4.2.2 Compass interference Materials used in the various components of the steering system as supplied shall not affect the accuracy and reliability of a compass mounted on the pedestal, if used, whatever the steering angle may be. 4.2.3 Draglink The construction of the draglink shall be such that it will allow ? 20 mm of length adjustment and a minimum of 1 5 ? angular misalignment. Means shall be provided to secure the draglink after adjustments (see Figure 2). Where the rudder lever and the operating lever are in the same plane and there is no angular misalignment, a clevis fitting is permissible.