Marine Drilling Riser Systems (MDRS)

MDRS SystemThe marine riser forms a continuation of the well bore from the top of the blowout preventer stack to the drilling vessel. The subsea well is drilled through the marine riser allowing the mud to circulate back to the mobile drilling unit.

In addition to diverter systems, riser joints, telescopic joints and FlexJoint™ connectors, all marine drilling risers contain high-pressure choke and kill lines, booster lines , hydraulic and glycol lines.  The Merlin™ Marine Riser System is also available with automated, hands-free makeup which dramatically cuts riser trip time and improves safety on the vessel.  Oil States now also offers complete riser systems for subsea mining applications.

Oil States provides a cost-effective, reliable, fast deployment with fast makeup, high-performance connection systems and accelerated delivery schedule. We are a proven provider of riser components and now provide complete riser packages.



Sales Contacts

United States
Email +1 713 445 2210

United Kingdom
Email +44 1224 290 000

Email +65 6773 7555

Email +55 21 3554 6644

Diverter System Valves

Key Features

  • Series DC Size Range: 10″ thru 18″ in ANSI Class 300, 600 and 900.
  • Xylan coating of bodies, bonnets, and retainers provides corrosion resistance for ease of disassembly and extended life.
  • Bore sizes designed to match or closely match Sch. 80, 100 or 120 pipe inside diameters to eliminate transition areas and erosion points.
  • Compact design saves space and weight versus traditional API 6D trunnion-mounted ball valves.
  • Wide selection of materials and valve configurations to meet application requirements.


  • Drilling diverter systems
  • 2″ thru 8″ valves offered for trip tank and booster line applications
  • Marine drilling risers


  • Engineering
  • Manufacturing
  • Assembly & Testing

Riser Adaptors

Key Features

  • Developed to form part of the system in connecting the drill floor to the subsea wellhead.
  • The subsea well is drilled through these risers, allowing the drilling mud to circulate back up to the rig.
  • The risers on the periphery are supplied with different auxiliary lines including choke, kill, booster and hydraulic lines


  • Marine drilling riser