Hydro Group is an industry leader in the engineering, design, and manufacturing of connectivity solutions. Since Hydro Group’s founding in 1982, they have helped clients across the world to solve their connectivity solutions for the subsea oil & gas, floating wind turbines, defense, and tidal stream sectors. With precisely engineered subsea electrical and optical interconnect packages, Hydro Group’s products can withstand the harshest environmental conditions.


  • Oil & Gas
  • Defense & Nuclear
  • Marine Renewable Energy

Subsea Cables

Hydro Group designs, manufactures and tests electrical, optical, and hybrid composite subsea cables. This includes tethers and underwater umbilical’s for all kinds of applications. Hydro Group’s cable products have been tested extensively for both performance and endurance. Some applications that Hydro Group cables have been used in the past are:

      • Power Cables (Underwater/Subsea)
      • High Voltage Cables
      • Composite Underwater Communication Cables
      • Underwater TV and Video Cables
      • Strain Bearing Cables
      • Composite Optical/Electrical Cables
      • Armored Cables, Tethers and Umbilicals
      • Laying-up of Hose, Cable and Strength Member Bundles
      • Neutrally Buoyant, Positively Buoyant or Negatively Buoyant Cables and Tethers
      • Polyurethane or Polyethylene Jacketed Cables
      • Specialist Cable Design Service

Subsea Connectors

With decades of industry knowledge, Hydro Group has the specialized capabilities to handle the growing complexity of underwater engineering. Hydro Group’s connectors undergo extensive testing for both performance and endurance and have been pressure tested to 10,000 PSI/6860 MSW/689 BAR. Some of Hydro Group’s connector capabilities are:

  • Fiber Optic Connectors
  • EXD-rated Connectors
  • HRC Hydro Renewable Connector (36kV)
  • Surface Mateable Coaxial Connectors, Metal and Rubber Keyed
  • Surface Mateable Hybrid Coaxial Electrical Connectors, Metal Keyed
  • HMK Hydro Metal Keyed Underwater Mateable Electrical Connectors
  • HRM Hydro Rubber Molded Connectors
  • HDM Hydro Deck Mate connector
  • HRS Hydro Rubber Sealing Underwater Mateable Electrical Connectors

Subsea Penetrators

With rugged designs that have been proven over decades of performance, Hydro Group’s fully blocked penetrators are the industry standard. Hydro Group’s penetrators are standardly built from 316 stainless steel or customized using titanium, aluminum, and silicon bronze.  Their penetrators have been tested up to 10,000psi.

Subsea Penetrator Features:

  • Fully pressure blocked right-angled or in-line designs
  • Robust design
  • 316 stainless steel or titanium, aluminum, and silicon bronze
  • Electrical, coaxial, and optical designs
  • Tested by Lloyds, DNV, and ABS
  • Voltage ratings up to 3,000 Volts RMS
  • Non Magnetic versions available
  • Mono Directional depth rated to 1,500 MSW
  • Bi-Directional Manned pressure vessel depth rated to 455 MSW

Submarine Pressure Hull Glands

Hydro Group’s pressure hull glands are designed specifically for submarines and bring an electrical or optical circuit from outside of a submarines pressure hull to the inside. Due to the need for pressure hull glands to endure high pressure during dives and rapid ascents, Hydro Group’s high pressure glands have been extensively tested for performance and endurance, as well as shock tested to PTS 14299.

Submarine Pressure Hull Glands Features:

      • Fully pressure blocked
      • Proven shock tested design
      • Metric and imperial thread versions
      • Electrical, coaxial, and optical designs available
      • Available in normalized steel / nickel aluminum bronze as standard
      • Termination options include polyethylene TSP, coax tails, composite optical electrical tails
      • Molding options include polyurethane and polyethylene

Assemblies – Subsea Renewable Power Takeoffs

Hydro Group provides interconnection arrangements that offer a secure solution that is suited for Atlantic seawater. Their custom built Power Distribution Hub (PDH) offer flexible in-line connections while also not compromising reliability or ease of operation. Hydro Group’s 36kV Hydro Renewable Connector (HRC) allows for two subsea three-phase electrical cables to be mated without compromising circuit. Some features of Hydro Group’s assemblies include:

  • Deployed in a range of seabed conditions
  • Low environmental impact
  • Corrosion protection
  • Third party qualification
  • Maintenance-free
  • Cost-effective solution
  • 25-year operational lifespan


Hydro Group’s strain termination designs range from simple multi-core cables to complex umbilical’s containing many cable bundles together with strain and armor members. In the event of a lead being severed, there are water blocking inserts incorporated into the design to prevent water from spreading from one cable to another. Hydro Group’s strain terminations have been tested for performance, endurance, and destruction. Features include:

  • Designed to suit your working load
  • Mechanical termination of cable directly to connector back-shell or to bespoke strain bar
  • Available with load transferred to outer cable diameter for use with lifting buoys and cable grips
  • Customer specified cable break out tail length from main strain termination
  • Field Installable designs available
  • Full destructive tests available on request

Breakout Molds: Encapsulations & Splices

Hydro Group’s connectivity solutions ensure cable systems and terminations will exceed the operational life of the project for whatever subsea equipment you are looking to connect to. The integrity of Hydro Group’s breakout molds have been tested extensively and are field proven on large projects around the world. Features included:

  • Engineered bespoke design
  • Quality assured manufacturing and testing
  • Proven molding materials and techniques
  • Harnesses fully labeled to your requirement
  • Fast turn around
  • Turn-key delivery of tested systems

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