Harsh Environment Drilling Service — Transocean Equinox
(Service)
Location or Storage Country: Norway
Location: North Sea
Online Support Service: Yes
Interpretation of Data: Yes
Description:
The Transocean Equinox is a harsh‑environment, column‑stabilized semi‑submersible drilling rig of the GVA 4000 NCS design. It was constructed by DSME (Daewoo Shipbuilding & Marine Engineering) and entered service in 2015. The rig is DNV‑GL classified (+1A1 Column Stabilized Drilling Unit (N)) and sails under the Norwegian flag.
Designed for the Norwegian Continental Shelf and other harsh‑environment areas, the Equinox features a dual‑activity drilling capability with an offline stand building derrick, a 750 st hookload, and a MH Wirth top drive and drawworks. It is equipped with a subsea mudlift pump for controlled mud level (CML) operations, allowing it to drill in narrow pressure windows. The rig has a maximum water depth capability of 1,640 ft (500 m) and can drill to 27,887 ft (8,500 m). It also includes a DP‑3 dynamic positioning system and a mooring system for station keeping.
Overview:
Technical Specifications Table
| Parameter | Value |
|---|---|
| Design / Generation | GVA 4000 NCS |
| Constructing Shipyard | DSME (Daewoo Shipbuilding & Marine Engineering) |
| Year Entered Service | 2015 |
| Classification | DNV GL +1A1 Column Stabilized Drilling Unit (N) |
| Flag | Norwegian |
| Dimensions (L x W) | 380.5 ft (116 m) long x 318.2 ft (97 m) wide (main deck) |
| Drafts (max operating / operating / transit / survival) | 82.5 ft (25.15 m) / 76 ft (23.15 m) / 31 ft (9.45 m) / 64 ft (19.5 m) |
| Accommodation | 140 persons |
| Displacement | 64,638 st (58,639 mt) |
| Variable Deck Load (operating / transit) | 5,512 st (5,000 mt) / 3,306 st (3,000 mt) |
| Transit Speed | up to 7 knots |
| Maximum Water Depth (designed / outfitted) | 1,640 ft (500 m) |
| Maximum Drilling Depth | 27,887 ft (8,500 m) |
| Derrick | MH Wirth, beam leg construction, single lift, H: 170.6 ft (52.0 m); offline stand building |
| Hookload Capacity | 750 st (680 mt) |
| Drawworks | MH Wirth GH 3000 EG‑AC‑SV‑01 |
| Compensator | MH Wirth DSC – 750 st (680 mt) static, 500 st (454 mt) compensating; AHC 28 st (25.6 mt) compensating |
| Rotary Table | MH Wirth RTSS 60‑1/2″ – 1,250 st (1,134 mt) |
| Top Drive | MH Wirth DDM‑750‑AC‑2M |
| Tubular Handling | Riser feeding machine, 2 x pipe rack cranes, 2 x tubular feeding machine |
| Mud Pumps | 3 × MH Wirth 2,200 hp, 7,500 psi working pressure |
| High‑Pressure Mud System | Rated 7,500 psi; choke & kill manifold 15,000 psi |
| Solids Control | 5 × MH Derrick Dual pool 600 shakers |
| Controlled Mud Level (CML) | 1 MW subsea pump; depth rating 1,312 ft (400 m), 6,000 l/min pump capacity |
| Main Power | 6 × Wärtsilä 12V32 engines (5,850 kW each, 720 rpm), each driving Siemens 6,588 kVA AC generators; total 35.1 MW |
| Emergency Power | 3 main engines (one in each engine room) classified as emergency engines/generators |
| Power Distribution | Kongsberg Maritime K‑Chief 700 Integrated Automation System; closed ring / 3 split, 11 kV, 690 V, 440 V, 230 V |
| Fuel Oil Capacity | 16,354 bbl (2,600 m³) |
| Liquid Mud | 9,089 bbl (1,445 m³) |
| Base Oil | 3,956 bbl (629 m³) |
| Brine | 4,277 bbl (680 m³) |
| Drill Water | 9,485 bbl (1,508 m³) |
| Potable Water | 4,283 bbl (681 m³) |
| Bulk Material (barite/bentonite) | 3,213 cu ft (340 m³) |
| Sack Storage | 5,710 sacks (177 m³) |
| BOP Rams | Cameron EVO 18‑3/4″ × 10,000 psi, 5 ram preventers |
| BOP Annulars | 1 annular preventer |
| BOP Handling | Overhead BOP crane 2 × 165 st (150 mt) with aux winch |
| Marine Riser | 21″, 50 ft (15.2 m) long, WT 0.625″, 500 psi |
| Tensioners | Wire line, 4 dual and 4 single; max wire pull 756 st (686 mt) |
| Diverter | 16″ flow line, 2 × 16″ overboard lines |
| Tree Handling | Overhead Xmas tree crane 2 × 55 st (50 mt) aux winch; MH Wirth dual XT stack‑up with flush deck skidding arrangement and XT elevator from main deck to moonpool |
| Moonpool | 33.8 ft (10.3 m) Fwd‑Aft × 29.5 ft (9.0 m) Port‑Stbd + key slot to port side 16.7 ft (5.1 m) Fwd‑Aft × about 54 ft (16.5 m) Port‑Stbd |
| Thrusters | 6 × Wärtsilä FS3503-571, each 4 MW |
| DP System | Kongsberg DP Class 3 (DYNPOS AUTRO and DYNPOS‑ER) |
| Mooring System | POSMOOR ATA(R) – 4 × Rolls Royce windlasses, 8 primary lines + 4 pre‑lay |
| Cranes | 2 × Liebherr BOS 4200, 110 st (100 mt) at 29.5 ft (9 m) to 78.7 ft (24 m) internal lift / 74 st (67 mt) at 65.6 ft (20 m) external lift; 1 × riser handling knuckle boom crane, 38.5 st (35 mt) at 39.3 ft (12 m) to 82 ft (25 m) |
| Helideck | Rated for Sikorsky S‑61N, S‑92 |
Documentation:
Transocean Ltd.
Markets: Shell, BP, Chevron, TotalEnergies, Equinor
Total Employees: 6000
Locations: 1414 Enclave Parkway Houston, TX 77077, USA
Main Products/Services: Offshore drilling services, ultra-deepwater drilling, harsh environment drilling, rig management
Registration: Turmstrasse 30 CH-6312 Steinhausen Switzerland
Year Established: 1926