Iranian Classification Society Rules

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Section 1 Classification Registry


101. Definitions


1. Single point mooring


A simple point morring(hereafter referred to as “SPM") which permits a vessel to weathervane while the vessel is moored to a fixed or floating structure anchored to the seabed by a rigid or ar- ticulated structural system or by catenary spread mooring. Examples of such system are CALM, SALM, tower mooring, etc.


2. Fixed SPM


A tower mooring and a single anchor leg mooring(SALM) which are gravity based(fixed or pain- ned) system are defined here as fixed SPMs.


3. Floating SPM


A catenary anchored leg mooring(CALM) is an example of a floating SPM.


4. Anchor leg


Mooring element connecting the single point mooring structure to the point and is essential for sta- tion keeping of the system.


5. Buoyancy element


A buoyancy member provided to support the weight of mooring equipment or risers, and designed to resist differential pressure from submergence and internal pressure.


6. Cargo


Any fluid transferred between the moored vessel and the pipe line end manifold(PLEM) such as crude oil, petroleum product petroleum gas, slurry, and bunkers.


7. Hawser


Mooring line between SPM structure and moored vessel.


8. Hose


Conduit designed to convey fluids between supply and delivery points with significant relative movement and able to tolerate large deflections. Typically, a hose is comprised of a string or series of short hose segments joined together at flanged ends.


9. Floating hose


Hose or hose string located between the SPM structure and the moored vessel for the purpose of conveying fluid. When not connected to a moored vessel it remains connected to the SPM structure and floats on the sea water surface.


10. Underbuoy hose


Hose or hose string located between the SPM structure and the pipe line end manifold (PLEM) for the purpose of conveying fluids.


11. Main bearing


The bearing which supports the load from the mooring and hawser and provides the moored vessel to rotate or weathervane about the mooring structure.


12. Product swivel


image

A mechanism which provides for passage of cargo or product while allowing the


a mechanism for


main structure to

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weathervane freely with respect to the fixed or anchored structure without significant leakage at the rated design pressure.


13. Flexible riser


Conduit designed to convey relative movement and able one continuous length, used submerged.


14. Swing circle


The swing circle is the area


fluids between supply and delivery points with or without significant to tolerate large deflections. A flexible riser is usually comprised of for relatively greater water depth sand constructed to be used totally


swept by the moored vessel as it revolves about the mooring point.


102. Classification registry


1. SPM built and surveyed in accordance with the Guidances of this Society (hereafter referred to as "the Guidances") or with alternative arrangements equivalent to the Guidances will be assigned a class in the Registration Master Book.


2. SPM classed with the Society are, for continuation of the classification, to be subjected to the peri- odical surveys, and are to be maintained in a good condition in accordance with the requirements of the Guidances.


3. When a SPM classed with the Society makes an alteration or modification of such an extent as to influence to the SPM's original performances, the plans have to be submitted for the Society's ap- proval before the work is commenced and the alteration work has to be supervised by the Surveyor.


103. Class notations


1. The class notations assigned to the SPM classed with the Society are to be in accordance with the followings:

(1) For SPM built under the supervision of the Society.

+ ICS - Single Point Mooring

(2) For SPM considered to be fit as the result of surveys by the Surveyor after construction.

ICS - Single Point Mooring

2. The following data on SPM will be published in the Record.

(1) Latitude and longitude of the location of the mooring

(2) Length over all and displacement of the ship it is designed to moor

(3) Depth of water at the site

(4) Maximum hawser tension where applicable

(5) General types of cargo and other fluids which the mooring is designed to handle.


104. Classification certificate


1. Where single point moorings have undergone the classification survey during or after construction to the satisfaction of the Surveyor and approved by the Classification Committee, the single point moorings will be classed and entered in the Registration Master with the issue of the Classification Certificates.


2. Where single point moorings have undergone the special survey to the satisfaction of the surveyor, the classification certificate is issued newly.


105. Survey report

On completion of the Classification Survey, Special Survey, Annual Survey and Occasional Survey, the Survey Reports will be issued. Survey results, the date and description of the next surveys, etc. are to be stated in the Survey Reports. The Survey Reports will be used as notice to the Owners.

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106. Guidances for classification


1. Application of guidances


These Guidances are applicable to unmanned SPM and are generally intended for temporary moored vessels. These Guidances are applicable to those features of the system that are permanent in na- ture and can be verified by plan review, calculation, physical survey or other appropriate means. Any statement in the Guidances regarding other features is to be considered as a guidance to the designer, builder, owner, et al.


2. Related regulations


The Society may require to apply the "Rules for Classification of Steel Ships" for items not speci- fied in this Rules.


3. Owner's responsibilities

(1) Responsibilities of report

When any of the following cases occurs, the Owner is to report to the Society without delay:

(A) When the SPM is sustained with a sea casualty by which her present class is deemed affected.

(B) When the Owner is changed.

(C) When the SPM is withdrawn.

(2) Cooperation of survey

(A) When a ship is to be surveyed, it is the duty of the Owner to inform the Surveyor of the correct place and items of survey.

(B) The owner, master or their representatives are to attend the survey according to the items to

be examined and are to give necessary assistances.

4. Governmental regulations


The Society may require to apply governmental regulations for items not specified in the Guidances.


107. Plans and design data to be submitted


1. Plans


Plans showing the scantlings, arrangements, and details of the principal parts of the structure, asso- ciated piping and equipment of each SPM to be built under survey are to be submitted for review and approved before construction is commenced. These plans are to clearly indicate the scantlings, joint details and welding, or other methods of connection. In general, plans are to include the fol- lowing where applicable.

(1) General arrangement

(2) An arrangement plan of watertight compartmentation, including the location, type and disposition of watertight and weathertight closures

(3) Structural arrangement showing shell plating, framing, bulkheads, flats, main and bracing mem- bers, joint details, as applicable

(4) Details of watertight doors and hatches

(5) Welding details and procedures

(6) Corrosion control arrangement

(7) Type, location and amount of permanent ballast, if any

(8) Bilge, sounding and venting arrangements

(9) Hazardous areas

(10) Electrical system one line diagrams

(11) Location of fire safety equipment

(12) Mooring arrangement

(13)

Mooring components including anchor leg, associated hardware, hawser, and hawser load-de-

flection characteristics

(14) Foundations for mooring components, industrial equipment, etc. structure

(15) Anchoring system showing the size of anchor, holding capacity


showing attachments to hull of piles, pile sizes, and ca-

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pacity, etc.

(16) PLEM (Pipe Line End Manifold)

(17) SPM main bearing

(18)

Cargo or Product swivel including swivel driving mechanism, swivel bearing, electrical swivel

details

(19) Product or cargo system piping schematic drawing with bill of materials

(20) Design data of equipment, piping, and related components including min. and max. design pressure and temperature

(21) Ancillary piping system schematic drawing with bills of material

(22) Floating and underbuoy hoses/flexible risers

(23) Telemetry/Control system

(24) Navigation aids

(25) Methods and locations for NDT

(26) Plans for conducting underwater inspections in lieu of drydocking

(27) Test and inspection plan for all major load carrying or pressure retaining components including cargo or product swivel, electrical swivel, bearings

(28) Test procedures

2. Site chart


To demonstrate that navigational considerations have been taken into account in establishing the mooring location, a site chart of the mooring are is to be submitted in accordance with Ch 3 which shows as follows :

(1) Location of the mooring

(2) Potential navigation hazard

(3) Existing & planned navigation aids

(4) Bottom contour elevations

(5) Maneuvering area

(6) Swing circle

3. Site condition reports


Reports on subjects including the following are to be submitted in accordance with Ch 3, Sec 1.

(1) Environmental conditions of wind, waves, current, seiche, tide, visibility, temperature, and ice.

(2) Water depth at berth and throughout the maneuvering area, bottom soil conditions, and subsur- face hazards.

4. Calculations


In general, where applicable, the following calculations are to be submitted:

(1) Structural design in accordance with Ch 3, Sec 3

(2) Stability calculations in accordance with Ch 3, Sec 3

(3) Mooring and anchorage in accordance with Ch 3, Sec 4

(4) Piping in accordance with Sections Ch 4, Sec 1 and Sec 2

(5) Calculations for all pressure retaining and load bearing components in accordance with Ch 4

(6) Swivel stack static and dynamic analysis in accordance with Ch 4

5. Additional plans


Where deemed necessary by the Society, submission of additional plans and calculations other than those specified above may be required.


108. Information booklet & maintenance manual


1. For each SPM, a document is to be submitted. This document is to include as follows :

(1) Recommendations regarding operation and maintenance of the SPM facility

(2) The design criteria for the SPM

(3) Information regarding the mooring area

(4) Components of the SPM.

2. Items included in Information Booklet & Maintenance Manual

(1) Site chart

(2) Design vessel data, including deadweight length, draft and distance from bow to manifold.

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(3) Environmental design criteria with various sizes of vessels, including the operating wind, wave, current and tides.

(4) Design cargo transfer criteria, including type of cargo and design maximum working pressure,

temperature, flow rate, and minimum valve closing times including the vessel's manifold valves.

(5) Plans showing the general arrangement of the single point mooring component and details of those component required to be handled during operation or inspected during maintenance, in- cluding details of access to these components.

(6) Description of navigation aids and safety features

(7) Recommended procedure for the mooring disconnecting a vessel at the SPM.

(8) Recommended procedure for connecting disconnecting floating hose to a tanker's manifold.

(9) Recommended

maintenance schedule and procedures for the SPM facilities, including a check

list of items recommended for periodic inspection. Where applicable, procedures for adjusting anchor leg tension, removal and reinstallation of hoses, inspection of flexible rises, adjustment of

buoyancy tanks, and replacement of seals in the cargo swivel are to be included.

(10) Recommended cargo system pressure testing.

3. The information Booklet & Maintenance Manual is to be submitted for review, by the Society sole-

ly to ensure the presence of the above information which is to be consistent with the design

formation and limitations considered in the SPM's classification. The Society is not responsible the operation of by the SPM.


The information Booklet & Maintenance Manual required by these Guidances may contain formation required by flag Administrations.

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