SECTION 2 Definitions

201. Application

The definitions of terms which appear in this Annex are to be as specified in this Section, unless otherwise specified, and definitions of terms and symbols not specified in the Annex are to be as specified in Rules for the Classification of Steel Ships and Ch 1, Sec 2 of the Rules.

202. Definitions

1. Well is general term for any boring through the Earth's surface that is designed to find and acquire petroleum oil hydrocarbons.

2. Blowout preventer(BOP) is a device that allows the well to be sealed to confine the well fluids in the wellbore.

3. Blowout preventer stack is the assembly of well control equipment including BOP's, valves, and nipples connected to the top of the casing head.

4. Ram BOP is a blowout preventer that use rams to seal off pressure in the wellbore.

5. Annular BOP is a device with a generally toroidal shaped steel-reinforced elastomer packing ele- ment that is hydraulically operated to close and seal around any drill pipe size or to provide full closure of the wellbore.

6. Drilling spool is a short pipe placed in the blowout preventer stack to provide connections of choke and kill lines.

7. Lower Marine Riser Package (LMRP) is the upper section of a two-section subsea BOP stack consisting of the hydraulic connector, annular BOP, flex/ball joint, riser adapter, flexible chock and kill lines, and subsea control pods.

8. Riser is a vertical pipe that allows the well fluids to be circulated. A riser is installed from a BOP to a unit.

9. Riser tensioner is a device that allow the riser to be in tension to prevent compression load on riser.

10. Riser spider is a device used to support the riser string on the uppermost coupling support shoulder during deployment and retrieval of the riser.

11. Choke system is a system used to reduce wellbore pressure by control of the rate of the flow of drilling mud out of the hole when the well is closed in with the blowout preventer and a kick is being circulated out of the hole.

12. Kill system is a system that allows high density drilling fluid to be pumps into the well with the BOP closed to prevent a threatened blowout.

13. Accumulator is a pressure vessel charged with inert gas used to store hydraulic fluid under pres- sure for operation of blowout preventers.

14. Control pod is the assemblage of valves and pressure regulators which respond to control signals to direct hydraulic power fluid through assigned porting to operate function.

15. Agitators is a device that stir the fluid to keep solids from settling and maintain homogeneous mixture in the mud tank

16. Hopper is a con-shaped fitting that is installed to mix dry mud or chemicals.

17. Degasser is a device used to remove unwanted gases from the returned mud.

18. Shale shaker is a device used to remove cuttings from the returned mud.

19. Desander is a device used to remove sand from the returned mud.

20. Desilter is a device used to remove silt from the returned mud.

21. Centrifuge is a device used to remove very fine particles from the returned mud.

22. Mud tank is a tank which retain mud .

23. Trip tank is a tank which compensate the volume of drill string when pull drill string from the hole.

24. Diverter is a device attached to the wellhead or marine drilling riser to close the vertical access in order to prevent upward flow of well fluids and direct flow into a line away from the unit.

25. Kelly is the steel bar, four-, six-sided, suspended from the swivel through the rotary table and connected to the topmost joint of drill pipe to turn the drill pipe as the rotary table turns

26. Kelly cock is a valve close to protect the rotary hose from high pressure that may exist in the drill string

27. Mixing pump is a pump to circulate mud of mud mixing system to mix dry mud in mud.

28. Mud-gas separator is a vessel to separate gas from kick fluid and mud depressurized by chock manifold.

29. Mud pump is a pump to pick up mud from the mud tank and circulate mud.

30. Pulsation damper is a device used to smooth out the surge created by pistons as they discharge mud.

31. Standpipe is a rigid metal pipe that provides the high-pressure path way for drilling mud to travel approximately one-third of the way up the derrick, where it connects to a rotary hose.

32. Standpipe manifold is a manifold to connect mud pump discharge to standpipe and divide flow into several part.

33. Rotary hose is a flexible hose attached to standpipe to allow up-and-down movement of swivel

34. Swivel is a mechanical device that prevents the motion of the kelly being transferred to the drill- ing line and permit high-volume flow of high-pressure drilling mud from the fixed portion to the rotating portion without leaking.

35. Umbilical is a control hose bundle or electric cable used to control subsea function.

36.Derrick is a main load-bearing structure in drilling unit string, and top drive assembly.

37.Crown Block is a assembly of sheaves mounted at the drilling line is reaved.

38.Traveling lock is a set of sheaves which move up and paid out or taken in.

used as support structure for the drill derrick top (crown) through which the down in the derrick as drilling line is

39. Drawwork is a large winch located on the drill floor used to raise and lower the drill string, top drive assembly by taking in or paying out the drilling line through the crown block and traveling block.

40. Stabbing board is a folding platform located in the derrick which positions the stabbing hand (pipe stabber) while running casing. Similar to monkey board, but at a lower height.

41. Monkey board is a derrick man's working place which is installed in the derrick.

42. Cathead is a spool-shaped component on which hoisting rope is wounded. A cathead is fitted in the winch.

43. Catwalk is a ramp used to move riser sections, drill pipes, casing or tool joints from deck stor- age to the drill floor.

44. Riser running tool is a A device that joins to the upper end of a riser joint to permit the lift- ing and lowering of the joint and the assembled riser string in the derrick by the elevators.

45. Water table is a step that is installed at top of derrick to allows to access to crown block

46. Acoustic control system is a subsea control system that uses coded acoustic signals for commu- nications and is normally used as an emergency backup having control of a few selected critical functions.

47. Autoshear system is a safety system that is designed to automatically shut-in the wellbore in

Guidance Relating to the Rules for the Classification of Mobile Offshore Drilling Units 2015 13

the event of a disconnect of the LMRP. When the autoshear is armed, disconnect of the LMRP closes the shear rams on BOP stack.

48. Deadman system is a safety system that is designed to automatically close the wellbore in the event of a simultaneous absence of hydraulic supply and signal (control and communication) trans- mission capacity in both subsea control pods.

49. Multiplex control system(MUX) is a system utilizing electrical or optical conductors in an arm-

ored subsea umbilical cable such that, on each conductor, multiple distinct functions dependently operated by dedicated serialized coded commands.

50. Test stump is a stump with wellhead profile used to support the BOP during surface test operations.

are in- pressure

51. Gimbal is a shock absorbing support for the riser spider which allows some angular movement of the spider and riser relative to the rig support structure.

52. Setback is a substructure which supports vertically standing

53. Tool joint is a connection part of each drill pipe.

tubular goods at bottom.

54. Riser Recoil System is a means of limiting the upward acceleration of the riser when a dis- connect is made at the riser connector.

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