SECTION 3 Survey

301. General

1. Drilling systems classed with the Society are to be subjected to the following surveys to maintain the classification. Periodical surveys of drilling systems are to be carried out at periodical surveys of the unit in which the drilling systems are installed.

(1) Special Surveys

(2) Annual Survey

(3) Occasional Surveys

2. Damage, failure and repair

(1) Examination

Damage, failure, deterioration or repair to the drilling system or components which affects Classification is to be submitted by the Owner for examination by the Surveyor at the first

opportunity.

(2) Repairs

Where repairs to the drilling system or components that may affect classification are planned in advance, a complete repair procedure, including the extent of the proposed repair and the need for the Surveyor’s attendance, is to be submitted to and agreed upon by the Surveyor reason-

Guidance Relating to the Rules for the Classification of Mobile Offshore Drilling Units 2015 29

ably in advance. Failure to notify the Society in advance of the repairs may result in suspen- sion of the drilling system’s classification until such time as the repair is redone or evidence is submitted to satisfy the Surveyor that the repair was properly completed. This requirement ap- plies also to repairs during voyage.

This requirement is not intended to include maintenance and overhaul to hull, machinery and equipment in accordance with recommended manufacturer’s procedures and established marine practice and that does not require the Society's approval. Any repair as a result of such main- tenance and overhauls that affects or may affect classification is to be noted in the ship’s log and submitted to the Surveyors.

All repairs found necessary by the Surveyor are to be completed to his satisfaction.

3. All annual and special surveys are to be carried out in accordance with an examination and test plan developed by the Owner and agreed by the Society for periodical inspection and testing of the overall drilling system.

4. The examination and test plan is to explain how each system and equipment is to be examined and tested during annual and special survey.

5. Maintenance records of the drilling system are to be part of the record kept onboard the drilling unit.

6. When the Society is authorized to perform surveys on behalf of a governmental authority, or when requested by the Owner, items as specified by the governmental authority or the Owner will be surveyed. Reports indicating the results of such surveys will be issued.

7. Annual and special surveys are to be scheduled preferably when the Owner has scheduled an over- haul of the drilling system. Annual Surveys are to be scheduled to coincide with the overhaul and testing of the BOP.

302. Maintenance manuals/records

1. Maintenance records are to be kept and made available for review by the attending Surveyor. The maintenance records will be reviewed to establish the scope and content of the required Annual and Special Surveys that are to be carried out by the Surveyor.

2. During the service life of the drilling system, maintenance records are to be updated on a continu- ing basis.

3.

303.

1.

The Owner is to inform the Society of any changes to the maintenance procedures and their fre- quencies as may be caused, for example, by changes or additions to the original drilling equipment.

Annual Survey

At each Annual Survey, the Surveyor is to verify the effectiveness of various systems and equip- ment by visual examination and testing, as appropriate. As a minimum, the following is to be car- ried out to the satisfaction of the attending Surveyor.

(1) Review of Owner's maintenance manual and relevant records to confirm that a suitable main- tenance program has been followed, periodical testing requirements have been carried out and that any repairs, reconditioning or renewals of well control equipment, BOP controls, riser sys- tem, pressure vessels, electrical systems, drilling hoisting system or lifting devices were carried out according to the applicable standards and the requirements of this Annex.

(2)

(3)

Review of database for approved changes made to the drilling system, and examination of this equipment to the extent deemed necessary by the attending Surveyor.

Exposed surfaces of the derrick, drilling hoisting systems, lifting devices, burner booms, stab-

bing boards, racking platforms and drilling equipment foundations are to be examined and placed in satisfactory condition, as found necessary. The inspection of the derrick and related structural members will include the following.

(A) The general condition of the structure, especially bent, missing or abraded parts and lost corrosion protection coatings.

(B) Tightness of

bolts.

(4) (C) Condition of wire ropes and fittings.

Examination of all mounting hardware and the structure of base-mounted winches and other lift-

30 Guidance Relating to the Rules for the Classification of Mobile Offshore Drilling Units 2015

(5) General external examination so far as accessible of the drilling systems as specified in Ch 1,

102. or damage, excess corrosion, fracturing or malfunctions.

(6) Protective covers, insulation, shrouds and protective guards around moving parts are to be found in place and in functional condition.

(7) Derrick walkways and ladders, drill floor and drill system machinery spaces to be surveyed with particular attention to fire and explosion hazards and confirmation that emergency escape

routes are not blocked.

(8) External examination of pressure vessels and their appurtenances, including safety devices, foun- dations, controls, relieving gear, piping systems, flexible hose, hydraulic hoses, insulation and gauges.

(9) Examination of safety shutdown devices.

(10) General examination of all electrical and instrumentation systems, including protective devices

and cable supports.

(11) Examination of mud and cement systems.

(12) Examination of the BOP test log and maintenance records.

(13) Testing of the BOP equipment in accordance with API RP 53

(A) Pressure and functional testing

(B) Control system testing

(C) Pressure testing if any shear rams were used in an emergency

(14) Review BOP inspections and maintenance records in accordance with Section 17 and Section 18 of API RP 53.

304.

Special Surveys

1. The Special Survey is to include all items listed under the Annual Survey.

2. In addition to Par 1, the followings are to be carried out to the satisfaction of the attending Surveyor.

(1) Review of Owner's maintenance records to verify periodical testing requirements have been car- ried out and that any repairs, reconditioning or renewals of well control equipment, BOP con- trols, riser system, pressure vessels, electrical systems, drilling hoisting system or lifting devices were carried out according to the applicable standards and the requirements of this Annex.

(2) Internal examination and thickness gauging of pressure vessels and pressure-retaining compo- nents, testing of relief valves and pressure piping systems, as considered necessary by the Surveyor.

(3) Hydrostatic testing of pressure vessels and other pressure-retaining components related to the drilling system to their maximum allowable working pressure.

(4) Hydrostatic testing of drilling system piping systems and flexible hoses to their maximum al-

lowable working pressure.

(5) Examination and check of insulation resistance of motors that are part of the drilling system.

(6) Examination of rotating drilling machinery to verify suitable operation, free from excessive vibration.

(7) The blowout preventer is to be subjected to a complete performance test and pressure-tested to

its maximum allowable working pressure.

(8) Examination of mud and cement pump fluid ends.

(9) Functional testing of derrick gear, drilling hoisting systems and derrick floor lifting devices.

(10) Close examination of the condition of welded joints on the derrick and associated structure, including nondestructive testing (including thickness gauging if required) of any suspect areas noted by the attending Surveyor.

(11) Examination of the equipment associated with the well control system and their maintenance records.

(12) Satisfactory functioning of the emergency power equipment to ensure proper operation.

CHAPTER 3 MATERIALS, WELDING AND NONDESTRUCTIVE EXAMINATION