BS ISO 13728:2012 pdf download

BS ISO 13728:2012 pdf download.Ships and marine technology一Ship’s mooring and towing fittings – – Panama chocks.
6 Materials
The following rnatenal shaH be used for manutacttxing the Panama chocks:
— Chock: steel casting matenal having a yield point of not less than 235 N/mm2 or equivalent.
The carbon contents of the steel casting shall not be more than 0,23 % considenng weldability.
7 Construction
The foundation of the Panama chocks shall be determined by considering the actual load directio.i The foundation and welding connections to the hull shall be guaranteed reliable transmission of the maximum loading of the Panama chocks to hull construction without any plastic deformation or cracks,
8 Manufacturing and inspection
8.1 All surfaces of the Panama chocks, including welding, shall be free from any visible flaws or imperfections.
82 All surfaces In contact with the ropes shall be tree from surface roughness or irregularities likely to cause
damage to the ropes by abrasion.
8.3 The Panama chocks shall be coated extemally with an anti-corrosion protective finish,
9 Marking
9.1 The safe working load (SWL) intended for the use of the Panama chocks shall be noted in the towing and mooring plan available on board for the guidance of the shipmaster. as specified in MSC!Circ. 1175.
9,2 The actual SWL on board shall be determined by considering the foundation and under deck reinforcement, and it shall be marked on the towing and moonng plan. The actual SWL slial not be over the SWL indicated in this International Standard
9.3 The Panama chock shall be clearly marked with its SWL by weld bead or equivalent, The SWL shall be expressed in tonnes (letter ‘t) and be located so that it is not obscured during operation of the fitting.
EXAMPIE SWL XXX I
9.4 The SWL mark shall be placed on the foundation of the chock or on deCk.
9.5 The radii of edges and corners not shown In Figure 1 shall be of minimum 25 mm.
A.1 General
The Panama chocks were designed in accordance with the technical requirements of the Panama Canal as
listed below:
Bearing surface radius: not less than 180 mm.
Single chock: opening area: min. 650 cm2, 305 x 230 mm, 45,36 t SWL.
Double chock: opening area: min. 900 cm2, 355 x 255 mm, 64,00 t SWL.
The strength of the Panama chocks was evaluated by finite element model analysis and determined based on the design criteria.
A.2 Loading
The Panama chocks shall be designed to withstand the horizontal and vertical load cases.
The horizontal and vertical loadings were considered individually,y but both loadings were not considered simultaneously.
A.2.1 Case 1一Horizontal loading