The Sea Con Group headquarters is based at Sea Con Brantner & Associates in El Cajon, California, and employs some 200 people. It houses both design and production facilities for the US market, as well as exporting its products through a worldwide network.

Seacon (Europe) Ltd., formerly Sea Connections Systems, was the first international addition to the group in 1987. Design, engineering, manufacturing, quality control and testing all take place within this facility. A highly successful range of products which include the Wet-Con, Metal Shell (MSS), 55 and U-Mate ranges are manufactured at Seacon (Europe).

As the industry switches over to fiber optics for more subsea applications, Seacon (Europe) continually develops new connectors to keep pace. These range from a single way through to a 48-channel and has led to the introduction of a new range of standard, drymate, fiber optic, hybrid connectors named Opti-Con.

Sea Con Global Production was created in 1989 in order to provide a quality, low-cost solution for the manufacture of underwater electrical connectors. As a result of continuous success, Sea Con Global Production has become the main rubber molded and composite connector manufacturer within the Sea Con Group.

Located in the Tijuana business district of Mexico, Sea Con Global Production has the capability to produce quality connectors with very quick turnaround times. In addition, the specialized engineering and product development departments can design and produce special application connectors to meet individual requirements. Sea Con Global Production's vast product range includes the original Marsh & Marine Rubber Molded and Glass Reinforced Epoxy (GRE) connectors, as well as the manufacture of the All-Wet/Wet-Con, Micro Wet-Con, and Hummer, the latest ultra-miniature connector range.

Sea Con Advanced Products was formed by the group in 1999 to focus directly on the Lockheed Martin-designed HydraStar and CM2000 high-integrity underwater mateable connectors. Based in California, Sea Con Advanced Products continues to develop state-of-the-art products, including the HydraLight and MicroStar optical wetmate connectors, which are based on the HydraStar technology, together with the S-Series and Photon optical connector ranges.

In addition to the underwater mateable connectors, Sea Con Advanced Products also designs and manufactures Single & Multiple Channel Optical Fiber Penetrators. Sea Con Advanced Products provides full service and support for optical underwater mateable connectors and electrical underwater mateable connectors, as well as consultancy services. The company works closely with customers to determine the appropriate optical and electrical connection systems.

Sea Con Giannini is the latest member of the Sea Con Group. Its acquisition in 2001 has added a new dimension to Sea Con's current vast range of products. Based in Coachella, California, Sea Con Giannini manufactures a full line of hermetically-sealed limit switches, proximity switches, potentiometers and magnetic couplings. They are also able to offer a range of plastic switches and has recently developed a proximity switch utilising Sea Con's connector technology.

Over the last few years the Sea Con Group has completed many successful onsite terminations, particularly for fiber optics. Due to cross training on products for personnel, Sea Con has been able to respond to urgent requests for onsite work across the globe. Visit www.seacon-usa.com for more.

Schilling Robotics
The SeaNet cable/connector from Schilling Robotics provides a robust, reliable connection to electrical power and telemetry for a wide range of remotely-operated underwater devices, including sensors, cameras, lights, thrusters, actuators, and tools.

SeaNet cables can be used to connect devices to almost any remotely controlled system. If the control system uses the Schilling Robotics SeaNet hub (a compact, lightweight device for communications and power distribution), the device being added to the system is simply fixed in place and a standard SeaNet cable/connector is attached between the device and one of the hub's ports.

The SeaNet cable assembly can be configured with a variety of connectors that are attached to an actively pressure-balanced, oil-filled urethane cable. Connectors at both ends can be SeaNet units (with or without status indicator lights), or one connector can be a third-party, customer-specified unit. One end of the cable can also terminate without a connector (cable whip). This configuration variety allows SeaNet cables to be used with virtually any control system and any device requiring telemetry or power.

Each standard cable contains seven conductors: two for power, one for ground, and four for signals. In typical configurations, two signal conductors are used for video and two for data transmission. Alternative conductor and power options are also available.

The power and signal channels are easily monitored using the bright LED status indicator lights that show through a clear window in the connector head. This lighted connector can be attached on the cable's control system end or the device end.

With the standard cable, the power indicator LED (red) is lit if at least 18 VDC is being applied across the power pins. A data indicator LED (amber) is lit for 0.5 seconds after a transmission on that line. If transmissions are made more often than every 0.5 seconds, the LED will be continuously lit.

Spring-loaded contacts on the SeaNet connector ensure that the connection is always sound. A positive locking feature allows cable disconnection only when two tabs on the connector head are simultaneously pressed.

The connector head has an incorporated integral perimeter lip seal that is not vulnerable to damage during installation and does not use an O-ring that could be lost or damaged. A fluid check valve in the connector face prevents leakage of compensation fluid when the cables are disconnected.

Cable penetrators (mating connectors) are available to adapt devices for use with SeaNet connector heads. The penetrator's electrical traces are a series of concentric circles, allowing an unlimited number of clocking positions for the cable. Penetrators are available to either allow or exclude the flow of compensation fluid to the device.

An all-purpose SeaNet adapter is also available to provide an interface to SeaNet connectors. The adapter is a four-inch cube with four threaded ports of different sizes, allowing installation of a mating connector in the adapter for the device being controlled. The adapter contains a flow-through SeaNet penetrator for connection to the SeaNet cable/connector, allowing fluid from the SeaNet cable to compensate the adapter cavity.

PDM Neptec
PDM Neptec is a leading engineering company in the supply and manufacture of underwater connectors, cable assemblies, and bespoke subsea connection systems. With 20 years of experience, the company now has 35 employees and provides solutions to its commercial and military customers around the world from its large manufacturing facility of 18,000 square feet near London in the UK.

The company operates within a number of principal areas including connectors and cable assemblies, polyurethane and polyethylene moulding/encapsulation, and specialist subsea engineering, although there is a great deal of overlap between these business operations.

PDM is the European distributor for the major manufacturer of underwater connectors and penetrators, Impulse, based in San Diego, California. Impulse manufactures a full range of underwater electrical connectors and penetrators in various materials, including their Glass Reinforced Epoxy, Rubber Moulded, Metal Shell, Wet Pluggable, IE55/IE55V, Underwater Pluggable, Miniature High Density (MHD), and Titan series. Contact counts are available from one right up to 96 and all can be used at depths down to 22,960 feet (7,000m). PDM provides Impulse connectors either off the shelf or as part of PDM's full termination service.

PDM Neptec's termination service covers the termination of cables with connectors from Impulse, PDM's own fiber optic connectors, or any other connector manufacturer at the customer's request. In addition the company regularly encapsulates sensors, transducer arrays, and other active/passive devices in a variety of moulding materials. Polyurethane moulding materials are available in twin-pack form for customers to use in repairing damaged cables or for their own connector/cable terminations.

The PDM Quickcure Moulding System (QMS) provides customers with a rapid means of repairing damaged cables. The QMS includes the Quickcure Mould Heater (QMH), mould tools, twin-pack polyurethane moulding material, primers and mould release agent. Using the QMH to mould at a temperature of around 60ĄC means that mouldings are finished in 20 minutes rather than the 24 hours it would take at room temperature.

The specialist subsea engineering skills and expertise offered by PDM's department of six engineers allows the design of its own connectors and custom produced connection systems. PDM has developed its own range of fiber optic and hybrid connectors and penetrators pressure rated to 22,960 feet (7,000m) and with optical losses of less than 0.2dB at operational wavelengths. The range is highly customizable, allowing hybrid versions with single or multi-mode fibers and electrical contacts in the same connector.

A clear example of PDM's ability to easily design, develop, and produce customer-bespoke connector solutions is the company's pluggable penetrator system. Designed in particular for oil and gas subsea electronics modules, the technology consists of a pluggable "penetrator" onto which a customer-specified number of specially designed connectors can be connected. Current designs cater for up to 30 two-pin connectors, but the technology can be adapted to accommodate any number of connectors, each having any number of contacts. Any unused sockets of the pluggable penetrator are simply blanked off with dummy connectors. In this way each electronics unit, sensor, etc., has its own connector allowing it to be swapped out, removed or added in via the pluggable penetrator with incredible ease.

PDM Neptec is ISO 9001:2000 registered and all production undergoes electrical testing with the option of accelerated-life and pressure testing. The company's customer base includes some of the world's biggest players in the areas of military and commercial ROVs, AUVs, oceanography equipment, diving systems, stealth systems, oil and gas industry projects, and seismic surveys.

JDR's Buoy Riser Cable
Monterey Bay Aquarium Research Institute's (MBARI) Ocean Observatory System (MOOS) concept supports a broad range of instrumentation and sampling strategies, including benthic instrument clusters covering up to 10km of seafloor, upper water column instrumentation, and AUV docking operations. JDR Cable designed a specialized buoy riser cable for the system, which can be broken down into a number of simple stages.

First is the requirement for electrical power, which defines the conductor size to meet the line voltage drop and current rating, and the insulation material and thickness to meet the voltage rating. Voltage and current rating has implications through the entire system and must be evaluated in context with other requirements such as DC-DC converters, cable diameter/weight, connectors, power supplies, and most of all safety needs.

Second is the signal and data format and rate. With long length cables (up to 4km for MBARI's MOOS) high bandwidths are inevitable, resulting in optical fiber as the logical choice for compact size and transmission capability. Given the operating environment of up to 400 bar seawater pressure, the only design consideration becomes pressure survival of the optical fiber. A stainless steel loose tube buffer is the preferred option as this isolates the fiber from the seawater pressure and from cable elongation under load.

Third is the strength member type and construction which must survive the load requirements from cable self weight in sea water, and the dynamic tension and flexing loads from the deployed configuration.

As a riser cable is subjected to the vagaries of the sea, it will see a wide range of loading over a significant number of cycles, and is perhaps the key element of the cable system. The design of such a strength member is not as easy as first appears, and a number of parameters play important and conflicting roles.

The driving factor behind a strength member is to limit the elongation of the cable under the working load. Copper conductors can live with an elongation of 0.3 to 0.4 percent before yield takes place. Excessive yield in a conductor can lead to tensile failures or when load is released to "Z" kink failure. Cabling the conductors into a helix helps to relieve the elongation such that approximately 0.6 percent cable stretch is equivalent to 0.35 percent conductor elongation.

While tensile strength and safety factors are important, the tensile modulus of the cable directly effects the maximum working load. A strength member material must therefore have a high tensile modulus.

For deepwater applications the weight of the cable itself provides much of the tensile load. Thus this can be minimized if a low-density strength member is used. This is typically referred to as the strength-to-weight ratio, but is more accurately stated as the modulus-to-density ratio. High tensile steel has an excellent modulus (200 GPa) but a high density (7860 kg/m3) giving a ratio of 2.6.

High strength fibers can offer substantial benefit. Standard para-aramid fiber (Kevlar, Twaron) has a ratio of five, as does liquid crystal polymer fiber (Vectran), while high modulus aramid has a ratio of seven. HMWPE fiber (Spectra, Dyneema) has a ratio of 10, and a density less than water, but does have the drawback of creep under higher loads.

The strength member should clearly be constructed from either aramid fiber or LCP fiber.

There are three principle ways in which the strength member can be constructed. The most efficient method, as regards cable stretch, is to use the fiber as a central core unit. This method offers the additional benefit of low torque and rotation. The main drawback with this cable is its lack of torsional stiffness, that is, it can continue to twist up without offering any resistance.

The best torsional balance is achieved by constructing the strength member as a braid around the outside of the central core cable. This has the added benefit of being torsionally stiff when twisted. The main drawback with this construction is its high level of elongation under load and the abrasion of the fibers at each crossover point in the braid.

The favored construction technique is as a contra-helically applied serving, where the elongation is low, torque is balanced, and self-abrasion of the fibers is minimized.

Fibre re-inforced cables share a common problem. Under cable flexing the fibers move relative to each other and abrade. Each abrasion cycle damages the material causing a loss of strength. The construction method can minimise the self-abrasion by using separation layers between the helical layers, however the intra-layer abrasion can only be minimized by material selection.

The poorest abrasion results are seen with aramid fiber, and the best seen with HMWPE. Vectran fiber also shows excellent self-abrasion properties.

Obviously one cannot test the cable over many years, so after JDR's predefined test regime, each sample is pulled to failure to evaluate the loss in strength as compared with the as new strength. An aramid cable design achieved only 23 percent of its original strength, while the Vectran cable retained 88 percent of its as-new strength.

On the basis of the test results, JDR Cable Systems manufactured and delivered a new riser cable to MBARI for installation in April 2004. JDR expects the cable to be as successful as its buoy riser cables currently in operation with the Ocean Net System, rated for 19,600 feet (6,000m) seawater depth.

The Cortland Companies
The Cortland Companies - Cortland Cable, Cortland Fibron, and Puget Sound Rope - offer a wide range of custom engineered cables, umbilicals and ropes. They design and manufacture cables, umbilicals, and ropes utilizing new technologies and innovative constructions to meet the demanding, and often harsh, environments that offshore market applications require. Cortland's ISO-certified facilities in New York, Washington, and the UK are advancing technology with highly engineered solutions.

High Alternating Voltage Low Electronic Stress (HAVLES): This is a unique process that permits high voltage cables to utilize a standard thermoplastic core extrusion. This allows for stable high voltage insulation, ease of termination, and dynamic use. Traditional methods required semi-conducting screens that must be co-extruded with the insulation, complicating termination and risking eventual break-down. The new design provides a safer, more reliable product.

Lightweight Tethers: The Cortland Companies, along with a major European compounding company, recently developed a low specific gravity sheathing material. As the first new material to be introduced in this market sector for a considerable time, it has significantly improved the buoyancy for cable and tether designs. This exclusive product allows for greater design flexibility.

Thin Wall Insulation for ROV Tethers and Main Lift Umbilicals: Thin wall insulation technology allows for smaller and more compact cable/umbilical assemblies with higher voltage ratings. By reducing overall diameters and weight compared to conventional core technology in deep water applications, significant impacts can be achieved on handling equipment size and cost.

High Tensile Strength Armor Packages: The Cortland Companies, in conjunction with an internationally recognized wire rope company, developed a unique wire drawing process that produces very high tensile wires that are two to three grades higher than any other product. This enables the production of cables and umbilicals that are smaller in diameter, lighter in weight, and with lower drag coefficients than other products in the market.

Ruggedized Optical Cable (ROC): ROC was developed as an oceanographic cable for remote deployment from precision wound cable packs. It consists of a dual buffered optical fiber protected by a pre-formed high tensile Inconnel armor and an outer jacket with a 2.2mm finished diameter. The breaking strength is over 300 pounds.

The cables are flexible, crush-resistant, cut-resistant, and able to withstand the high hydrostatic pressure of deepwater deployments. This has proven to be a durable fiber packaging system that works well in demanding environments as well as performing superbly as an element in larger cables. The kink and crush resistance is far superior to loose tube optical elements and the unique mechanical coupling of the fiber to the armor is well suited to long vertical deployments.

Strum and Drag Suppression: In addition to Cortland's traditional one-sided, two-sided, and patented four-sided hair fairings, they have developed a system of ribbed outer jacketing which provides strum and drag suppression. The strum resistant jackets are manufactured with a series of raised ridges which protrude from the jacket in a sinusoidal pattern. This system of vortex shedding ridges is more durable and adds significantly less to the finished cable diameter than traditional fairings. No special handling equipment or terminations are required for cables using this jacket.

Alpha Thames
A unique wet-mateable, high-voltage connector developed by Alpha Thames (UK) successfully uses nitrogen insulation. The ELEx connector is believed to be the only gas-filled wet-mateable connector in existence and was developed to meet the need for dependable power supplies to the AlphaPrime oilfield development system. An AlphaPrime system can include pumps, separators and other components operating in very deep water where they might require up to 11,000 volts with 5MW of power. The ELEx connector was developed to perform repeated make and break cycles without jeopardizing the integrity of its insulation.

The ELEx connector consists of a three-pin male plug and a corresponding female socket. The pins were designed for permanent installation on the seabed structure and the socket is housed within a pressure vessel. The pressure vessel will typically be integrated within an AlphaPrime System Module that contains the equipment requiring the power. Once the pressure vessel has been locked in place, a Fluid Exchange Mechanism (FxM) forces the sea water out of the chamber, cleans and conditions the electrical contacts and secures the contact area in a dry, inert gas at three bar. Continuous monitoring for water ingress during the life of the connection provides a warning of potential failure and enables the FxM to be activated remotely to remove the water before problems arise.