Gateway to the business world

The Rise of The Umbilicals

Ian Probyn, The Senior Structural Analysis Engineer at DUCO Ltd., Technip, UK gives Energy Outlook an insight into the manufacture, working and the significance of umbilical systems at DUCO, Technip.

Ian Probyn is responsible for development of finite element analysis techniques of subsea umbilical systems at Duco. Umbilicals are used as the control and supply link for subsea Oil and Gas extraction equipment. Since joining DUCO in 2004 he has been responsible for developing and validating finite element analysis techniques, based on Abaqus, to assess the behaviour of the complex helical construction of the umbilical in structural and thermal scenarios. He graduated from Loughborough University in 1997 with a Bachelor’s degree in Automotive Engineering and worked as a crash simulation engineer for Rover, BMW and Land Rover where he developed vehicle body structures for crashworthiness using FEA software.

An umbilical is the control link that goes from either a floating vessel or a fixed platform down to the sea bed and connects into sub-sea equipment for oil and gas extraction. Umbilicals can either be static, where they are laid upon the seabed, or dynamic where they hang in the water column and are subjected to fatigue loading. There are of four general types- steel tube, thermoplastic hose, power cable and the hybrid umbilicals.

In terms of supply, the umbilicals carry chemicals supply for injection into the flow-line for flow assurance, electrical power supply and hydraulic power supply. In terms of control, the umbilical provides hydraulic and electrical control signals, and also optical control signals via fibre optic cables.

DUCO LTd. & Technip:
DUCO’s main facility is located at Newcastle upon Tyne in the UK. We have four manufacturing facilities: Newcastle-UK, Houston-US, Angola-West Coast of Africa and there's a new facility that is scheduled to commence its operations this year in Malaysia.

Since 2003 DUCO has been part of the Technip group. Technip provides full oil and gas capability in sub-sea, offshore and onshore, as well. When it comes to sub-sea equipment, Technip, designs, manufactures and installs, umbilicals, flexible risers, rigid pipelines. In terms of offshore, Technip is capable of engineering and construction of fixed or floating platforms adapted to all water depths for oil and gas production at sea. Onshore, Technip engineers and constructs all onshore installations for the oil and gas, petrochemical, and non-oil industries( including chemicals, life sciences, renewable energies…) So, the umbilical system is only a small, but vital, piece of the jigsaw puzzle which makes up a complete offshore installation.

Umbilicals in Deep Waters:
In deep waters, installation becomes very critical especially when it comes to being able to provide enough 'crush-resistance' to the umbilical to be able to hold on to it in an installation caterpillar. Finite element analysis can be used to assess the crush performance of the umbilical and ensure that the components inside are not likely to get damaged. For example, we can determine the upper working limits of those components and make sure that the umbilical system is installable with existing lay equipment.

On why no one makes them better than Duco Ltd. does:
Every umbilical system is purpose designed for the particular function and at Duco Ltd., we place a strong emphasis on research and development and engineering efforts. We thus have a very good resource of engineering back up. We also have very good quality systems for design and manufacture.

DUCO and Umbilicals:
Umbilicals aren’t the only products that Duco Ltd. manufactures. We also design the end termination systems and the sub-sea foundation equipment, for example mud-mats which sit on the sea bed supporting the end termination, enabling the umbilical to be connected in to the field by an ROV. We also design and manufacture the connector, or jumper umbilicals that join the main umbilicals from the end termination into subsea equipment such as ; christmas trees, manifolds and well-heads.

Umbilicals: The Components:
Some of the key components that go into the umbilical are steel tubes, thermoplastic hose- where the hose is made out of extruded polymer liners and has a braided Kevlar reinforcement to give it pressure retention and tensile strength, electrical cables, both signal and power and fibre optic cables. If it's a steel tube umbilical then the steel tubes provide the tensile strength, if it's a thermoplastic or power cable umbilical then there's a steel armour layer that's applied and that provides the tensile strength.

The umbilicals are helically laid and that provides flexibility in bending so the functional components are not over-stressed during bending.

Dynamic Umbilicals: The Anti- Fatigue Design:

The design requirements of dynamic umbilicals are considerably greater than that of the static umbilicals. The static umbilical, once installed on the sea-bed, is relatively benign. There are some instances in shallow waters where there's strong currents and the umbilical may need to be buried to prevent it being damaged or we can design it so it's has sufficient mass to keep it stable on the sea bed.

For a dynamic umbilical, which is suspended from a vessel, we need to think about fatigue and make sure that the steel tube components don't have metal to metal contact, therefore they are over-coated with a polymer material. We also need to design a bend stiffener, so that at the connection point with the vessel , the bending movement is controlled to avoid over-bending which may cause damage to the umbilical components.

We perform all the engineering, based on validated methods, to prove that the fatigue life of the umbilical is going to be sufficient for that particular installation. This can be very dependent upon the type of vessel that the umbilical is attaching to, i.e. whether it's a spar or an FPSO, as the dynamic motion can vary between types of vessel.

Response of Indian Market to Umbilicals from Duco:
A very positive one, indeed. Certainly, people coming to the stand(Technip - Oceantex 2010) say that they enjoyed the presentation yesterday.

Future of Indian Offshore Technology:
The energy demand for India is predicted to increase. The amount of energy that's being imported in terms of hydrocarbons is a high percentage, so I think India is making itself more self sufficient when it comes to energy supply. I think there will soon be more development in the offshore business in the future.


The Expert Angle

Mr. Ian Probyn
Senior Structural Engineer
DUCO Technip, UK

Ian Probyn, The Senior Structural Analysis Engineer at DUCO Ltd., Technip, UK gives Energy

Mr. Roger Moore
Principal Consultant

I like the look in a senior leader’s eyes when he/she recognizes “what they don’t know” about being a true leader from a safety/ business excelle.


  Know more about us:
  View our client list:
  The expert Angle:
  Energy industry celebrities:



Most Popular This Week

With Oceantex 2010, the Chemtech foundation brought to light the significance of offshore business in India differently. Held from 3rd to the 6th of March, 2010, Oceantex saw the world’s top Offshore, Marine and other energy sector related companies showcasing their services with leading edge concepts. The scope of offshore business in India was discussed and debated by experts from various parts of the world. View Full Report