BS ISO 03730:2012 pdf download

BS ISO 03730:2012 pdf download.Shipbuilding and marine structures- Mooring winches.
4.2 Material stresses
The winch manufacturer shall be responsible for determining the strength requirements of the component parts
of the wrnch to withstand all loads of the respective nominal sizes of mooring winches, as specified r Table 2.
4.3 Strength requirements
4.3.1 Winch drum load
The allowable calculated stresses of any affected part of the winch, based on simple elastic theory, shall not be greater than 0,4 times the upper yield strength (R.i) or the 0.2 % proof strength. non-proportional extension (Rpo2) of the material.
4.3.2 Maximum torque of prime mover
The allowable stresses in the affected parts shall not be greater than 0,9 times the upper yield strength (Reti) or the 0.2 % proof strength. non-proportional extension (RPo,2) of the material.
4.3.3 Winch holding load
The allowable calculated stresses of the affected parts shall not be greater than 0,9 times the upper yield strength (Reji) or the 0,2 % proof strength, non-proportional extension (Rp02) of the material
4.3.4 Other requirements
Related requirements of OCIMF should also be satisfied for mooring winches used in tankers
4.4 Operating devices
The direction of motion of the operating devices shall be such that the rope is hauled-in by clockwise movement at a hand-wheel or aank handle or alternatively movement of a hand4ever towards the operator, and vice versa.
If it has been agreed between the purchaser and manufacturer, the rope may be hauled in by antclockwise movement at a hand-wheel or crank handle.
The direction of motion of the operating devices shall be clearly and permanently marked.
Whatever the form of motive power, the operating devices shall, when under manual control, be arranged to return to the braking or stop position automatically, unless otherwise agreed between the purchaser and manufacturer.
4.5 Brakes
4.5.1 Automatic braking system
Electric winches shall be provided with an automatic braking system which operates when bringing the operating device to the stop or braking position, and also when there is no power on the winch. The brake shall be capable of holding a load on the hawser of 1,5 times the drum load and of stopping the drum rotation from its maximum speed without suffering damage.
For winches of hydraulic or steamdnve, when bringing the operating device to the stop or braking position. and also when there is no power on the winch, the drum shall be capable of holding a load on the hawser of 1.25 times the drum load, and the movement of the rope shall be controlled within 1.0 m!min.
4.52 Drum brake
All drums shall be provided with a drum brake capable of maintaining the holding load specified in 5.2.
For mooring winches used in tankers, the structure and performance of drum brakes should satisfy the requirements of OCIMF.
For tankers, they should also satisfy the requirement of OCIMF That each ship should reserve a complete set of brake test devices.
4.6 Drum design
4.6.1 Design rope
4.6.1.1 Steelwireropes
For design purposes, the drum shall be based on 6XJBWS.IWRC or 6x41WS.IWRC steel rope manufactured from 1 770 N/mm2 tensile grade wire in accordance with C.9 of ISO 2408.
The above requirement does not preclude the use of other types of steel wire rope in service.
4.6.1.2 Synthetic fibre ropes
General synthetic fibre ropes or high modulus synthebc fibre mooring lines may be used.
4.6.2 Drum diameter
4,6,2.1 Round strand wire ropes
The drum diameter shall be not less than 16 times the diameter of the rope.
4.6.2.2 Synthetic fibre mooring lines
The drum diameter shall be not less than 6 times the diameter of the synthetic fibre mooring line.
For high modulus synthetic fibres, the ratio of drum diameter and rope shall meet the requirements of the rope
manufacturer.
4.6.3 Drum capacity
Drum capacity shall be of two capacities. normar and Thigh. The minimum length of design rope to be stored on normal-capacity drums is given in column 12 of Table 2. High-capacity drums shall store twice the length of rope of normal-capacity drums.
4.6.4 Drum length
a) The drum length of normal-capacity drums shall be such that the total length of the design rope can be accommodated in not more than five layers. If it has been agreed between the manufacturer and purchaser, the layers should be applicable to other layers.
b) The drum length of high-capacity drums shall be such that the total length of the design rope can be accommodated in not more than eight layers.
c) The large loads should not be applied while more than four layers of rope are reeled on the drum, otherwise short life of rope will result, It is recommended that a split drum should be used, and the number of layers on the storage section may be increased,
d) The length of the working part of a split drum: for steel wire ropes and high modulus synthetic fibre ropes, the length of the working part of the drum shall be enough for winding oSlO turns; for general synthetic fibre ropes, it shall be enough for winding of 5-6 turns.