Section 3 Surveys After Construction

301. Annual surveys

1. Due range

Annual surveys are to be carried out within three(3) months before or after each anniversary date.

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2. Survey items

At each Annual Survey, the SPM is to be generally examined so far as can be seen and placed in satisfactory condition as necessary.

(1) Hatch

(A) Coaming

(a) Coamings including deck connection

(b) Hatch cover plating, stiffeners and brackets

(B) Hatches fitted with mechanically operated steel covers

(a)

Hatch cover(cover plating, stiffener),

(b) Cross joints

(c)

Gaskets, cleats and dogs

(C) Exposed steel hatch covers are to be examined to confirm structural integrity and capability of maintaining weathertightness.

(D) Where significant wastage of hatch covers is noted, thickness gaugings are to be carried out

and renewals made as necessary. Proper operation and functioning of hatch covers and se- curing arrangements is to be confirmed.

(2) Manholes, scuttles

(3) Ventilators, air pipes together with flame screens, scuppers and discharges serving spaces in the SPM.

(4) Watertight bulkheads, bulkhead penetrations, and the operation of any doors in the same.

(5) Guard rails, lifelines, and access ladderways.

(6) Verification of loading guidance and stability data as applicable.

(7) Verification that no alterations have been made to the SPM which affect the classification.

(8) Anchoring and mooring equipment including verification of mooring chain tensions.

(9) Confirmation that electrical equipment in hazardous locations has been properly maintained.

(10) Product lines, swivel, seal

(11) Confirmation that there are no potential sources of ignition in or near the cargo area and that access ladders are in good condition.

(12) Cargo equipment and piping apparatus including supports, gland seals, remote control and

shut-down devices.

(13) Bilge pumping system.

(14) Ventilation system including ducting. dampers and screens.

(15) Verification that cargo discharge pressure gauges and level indicator systems are operational.

(16) Structural areas of the SPM hull or buoy particularly susceptible to corrosion, including spaces used for salt-water ballast as accessible. Thickness gaugings may be required.

(17) Lights, navigational aids, etc., if applicable.

302. Special surveys

1. Due range

(1) Special Surveys are to be carried out at a date not exceeding 5 years from the completion date of classification survey or the due date of the previous Special Suruey.

(2) If the Special Surveys are carried out at a date which shall be more than 3 months earlier than

the due date of Special Survey, the next Special Survey shall be assigned at th date of 5 years after the completion date of concerned Special Survey.

(3) Special consideration may be given to Special Survey requirements in the case of single point

moorings of unusual design in lay-up or in unusual circumstances.

(4) Special Surveys may be commenced at the 4th Annual Survey after Classification Survey or

previous Special Survey and be progressed during

the succeeding year with a view to com-

pletion by the due date. As part of the preparation for the Special Survey, the thickness meas-

urement as the required for the forthcoming Special

Survey are to be taken to the extent acces-

sible and practicable in connection with the 4th Annual Survey.

(5) Where the Special Survey is commenced prior to the 4th Annual Survey, the entire survey is normally to be completed within l5 months if such work is to be credited to the Special

Survey. In this case, items are tank test, thickness measurement and docking survey.

2. Requirements of surveys

Special Survey of the SPM hull or buoy is to include compliance with the foregoing Annual

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Survey and Drydocking Survey requirements and in addition, the following requirements as listed below are to be carried out as applicable.

(1) Floating SPM system

(A) The following items are to be examined externally and internally for damage, fractures, or excessive wastage. Thickness gauging of plating and framing may be required where wastage is evident or suspected. Suspect areas may be required to be tested for tightness, non-de- structive tested or thickness gauged. External thickness gaugings may be required to confirm corrosion control.

(a)

SPM buoy or platform structure including bracing members

(b) Tanks, cofferdams, void spaces, sponsons, chain lockers, machinery spaces

(c)

Watertight bulkheads and decks

(d) All other internal spaces

(e)

The following compartments and spaces may be waived provided that upon a general examination, the Surveyor considers their condition to be satisfactory.

(i) Tanks and other normally closed compartments filled with foam or corrosion in-

hibitors

(ii) Tanks used only for lube oil, light fuel oil, diesel oil, or other non-corrosive prod- ucts

(B) Mooring components including chain stoppers, hawser padeyes, etc.

(C) Foundations and supporting headers, brackets and stiffeners from cargo transfer related appa- ratus, where attached to hull or deck structure.

(D) Survey of parts of the SPM which are underwater and inaccessible to the Surveyor may be accepted on the basis of an examination by a qualified diver carried out in the presence of the Surveyor. Survey by ROV(remotely operated vehicle), in lieu of a diver, is to be spe- cially considered. The under water examination is to be carried out in accordance with an approved procedure using two (2) way audio visual communication.

(E) At each Special Survey, thickness gaugings are to be carried out where wastage is evident or suspect At Special Survey No. 2 and subsequent Special Surveys, representative gaugings will be required.

(F) Special attention should be paid to the following areas.

(a) Splash zones on the hull, related structure

(b) In ballast tanks, and free-flooded spaces

(G) Where inspection of under water joints is required, sufficient cleaning is to be carried out in

way of, and water clarity is to be adequate to permit meaningful visual, video, camera or NDT examination as required. Every effort should be made to avoid cleaning damage to special coatings.

(H) All openings to the sea, together with the cocks and valves connected therewith are to be examined internally and externally while the SPM is in drydock, or at the time of under- water examination in lieu of drydocking and the fastenings to the shell plating are to be re- newed when considered necessary by the Surveyor.

(2) Fixed SPM system

(A) A drydocking survey or equivalent underwater inspection of the SPM shall be carried out.

This survey shall include examination of the following areas.

When underwater inspection in lieu of drydocking survey is requested, the underwater in- spection procedures including all NDT and structural detail inspection are to be submitted for review and approval. Surveyor is to use those approved procedures as basis for their surveys.

Any suspect areas where axcessive corrosion is evident shall be thickness gauged.

(a)

Entire hull structure of the SPM body

(b) Protective coating, cathodic protection system

(c)

Chain stoppers and their locking devices

(d) Floating hose connecting spool pieces, if applicable, and the underwater part of the flex- ible riser spool pieces.

(B) In any case gaugings shall be taken on the hull of the SPM when it has undergone service for 15 years or more.

(C) An examination shall be made on all anchor chains for excessive corrosion and wastage. In particular the areas to be specially examined are the areas having the most relative move-

ment between the chain links down sections of the catenary

and these areas are normally in way of the part of the chains. The chains shall also be

seabed touch inspected for

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loose studs and link elongation and sufficient representative locations shall be gauged for wear and wastage. Areas susceptible to corrosion such as the wind-and water areas are to be specially gauged.

(D) A close examination shall be carried out on all mooring components and accessibles struc- tural members which carry mooring loads. These structures include ;

(a)

chain stoppers, structures in way of the chain stoppers

(b) structural bearing housing and turret areas

(c)

structures in way of the mooring system components for the off-loading vessels.

(E) A general inspection shall also be carried out on the degree of scour or exposure in way of the anchor or anchor piles to ascertain that these components are not over exposed an ex-

tent that may cause a pull up on the anchors/piles.

(F) An examination shall be carried out on the main bearing of the SPM system.

This examination shall include visual inspection of bearing, if accessible, for water egress into the structural housing, corrosion, pitting and excessive wear. If the bearing is in- accessible at least the weardown shall be ascertained and the condition of the bearing seals verified. If disassembled the bearing rollers and the racer housings shall be specially examined.

(G) For other unconventional types of SPMs, special attention shall be paid to inaccessible part of structures. Suspect areas may have to be subjected to some form of NDT. Areas that are

inaccessible shall at least be verified in order by gauging the boundary structures.

(H) The chain tensions shall be checked and where found not in compliance with the of specifi- cations shall be readjusted accordingly. Excessive loss of chain tensions shall be

investigated. Tensions are normally checked by way of measuring their catenary angles and

their relative catenary water depths. Every SPM has its own designed acceptable chain ten- sions corresponding to a given chain angle with 1-2 degree tolerance.

(I) Fluid and electrical swivels shall be disassembled and examined for wear and tear and the

seals shall be examined for deterioration. Upon completion of the reconditioning of the fluid swivels, they shall be hydrostatically tested. Similarly the electrical swivels shall be in- sulation tested.

(J)

During underwater inspection of the SPM system the flexible risers shall be examined in- cluding all the support buoyancy tanks. Risers shall be inspected for kinks in high stress areas such as areas in way of the end flanges, areas in way of the arch support clamps and the bottom of all looped areas. Should spreader bars be fitted to separate more than one ris- er string they shall be inspected for excessive wear and tear. Excessively worn shackles and chain links of the spread bar system shall be renewed. Hydrostatic tests may be required to be carried out on the risers as deemed necessary by the attending Surveyor.

(K) Floating hoses shall be examined for kinks, surface cracks chaffing damages, etc. Hydrostatic and vacuum tests may be required to be carried out on the floating hose string as deemed necessary by the attending Surveyor.

(L) The entire compliment of safety equipment shall be examined in proper order. Safety equip- ment includes lifebuoys, obstruction lights, portable fire extinguishers, blinker lights for the floating hose strings, etc.

(3) Mooring hardware

(A) The complete mooring system including anchor, chains, chain stoppers, mooring line con- nectors, securing devices and pilings as applicable are to be examined Arrangements are to be made for examination of all underwater areas. Areas not accessible by divers may be ex- amined by ROV(remotely operated vehicle). All chain and accessories are to be checked for damage or wastage.

(B) Removal of one section of the mooring system for examination out of the water will be re- quired at Special Survey No. 4 (20 years of service).

(C) Mooring system component (flexible or rigid) for mooring of the attached vessel are to be

examined throughout provided this equipment is associated with the classed SPM. NDT of high stressed joints in rigid mooring connection may be required at the Surveyors discretion. Flexible hawsers are to be examined for wear and filament breakage. Items found worn may require replacement.

(4) Cargo hoses or flexible risers

(A) Cargo hoses

Cargo hoses forming part of the SPM classification are to be removed disassembled, pres- sure tested to rated working pressure and examined at each Special Survey. This requirement

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applies to all hoses that have been in service for five(5) years. In the event cargo hoses have been renewed or replaced with new hoses within the five(5) year period the above re-

quirements may be modified and removal and

testing deferred until the hose has been in

service five(5) years. Vacuum testing of cargo hoses is required in association with Special Survey or after five(5) years of service as indicated above.

(B) Flexible risers

An inspection manual for risers included as part of the SPM classification is to be sub- mitted to the Bureau for approval. The manual is to include procedures for the following:

(a)

Underwater examination of the flexible risers including arch support buoyancy tanks.

(b) Examination of high stress areas such as areas in way of the end flanges, in way of the arch support clamps and the bottom of all looped areas.

(c)

Examination of wear and tear on spreader bars, if fitted which separate one riser string

from another.

(d) Hydrostatic testing of flexible risers to be carried out to working pressure.

(5) Safety equipment

Safety equipment of the SPM is to be examined and tested as required by the attending Surveyor. Refer to Ch 4, Sec 4 for requirements applicable to the safety equipment.

(6) Swivel and cargo transfer equipment

Swivel assemblies, foundations, seals and associated piping assemblies are to be examined

externally. pressure retaining sections which convey corrosive or erosive materials are to be opened and examined internally. Thickness gaugings may be required to be taken on cargo transfer pipe lines and associated exposed equipment. Upon completion of the examination, the swivel assembly is to be hydrostatically tested to design pressure and the sealing capability of

the swivel is to be verified through one complete revolution.

(7) Electrical installations

Satisfactory operation of equipment is to be verified and circuits are to be inspected for possi- ble development of physical changes or deterioration. The insulation resistance of the circuits is to be measured between conductors and between conductors and ground. These values are to be

compared with those previously measured. Any large and abrupt decrease in insulation resistance

is to be further investigated and either restored to normal or reviewed as indicated by the con- ditions found.

303. Drydocking surveys or equivalent

1. Due range

An examination of the underwater parts of each SPM and associated mooring hardware is to be made at intervals not exceeding five(5) years. This examination is to align with the due date of the Special Survey.

2. Requirements of surveys

(1) Underwater parts of each SPM and associated mooring hardware

(2) External surfaces of the SPM

(3) Prior to examinatiorn, all mooring and anchoring attachments are to be cleaned including all openings to the sea, if any. Anchor legs including connecting hardware are to be examined over the full length from the lowest exposed point at the seabed to the connection point at the SPM.

304. Lay-up and reactivation

1. The Society is to be notified by the Owner that an SPM has been laid-up or otherwise removed from service. No periodical surveys are to be carried out for classed SPM when they are laid-up. Lay- up procedures and arrangements for maintenance of conditions during lay-up may be submitted to the Society for review and verification by survey.

2. In order to put the laid-up ship into service, the ship has to receive the heaviest kind of survey amongst all the due surveys during laid-up period.

305. Alterations

No alterations which affect or may affect classification are to be made to the hull or machinery of

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a classed SPM unless plans of the proposed alterations are submitted and approved by the Society before the work of alterations is commenced and such work when approved is carried out to the satisfaction of the Surveyor.