Materials & Manufacture
A typical flowline buoyancy arrangement will comprise of buoyancy elements held in position on the flowline using clamps.
All of our Flowline Buoyancy systems utilise the following materials:
Syntactic Foam Core
The buoyancy elements of each system have a composite syntactic foam core. This material has three main components:
- Base polymer
- Glass microspheres
- Macrospheres
The resulting material exhibits low water absorption and hydrostatic compression and is eminently suitable for extended subsea service. The syntactic foam has a nominal density which varies according to the specific water depth of the application.
Typical Densities:
| MSW (m) |
Density (kg/m3) |
| 200 |
325 |
| 500 |
420 |
| 1000 |
480 |
| 2000 |
500 |
| 3000 |
530 |
Buoyancy skin
The syntactic foam core is protected from impact and abrasion using a proven skin system that we have developed on our Uraduct® cable and flowline protection products. The principal material components used are Glass Reinforced Plastics (GRP) and high grade polymers. These materials can be adapted to include marine growth and anti-foul protection if required.
Clamps
Holding the buoyancy in position on the flowline is critical to the overall flowline system performance. We have several clamping technologies available to use, their selection dependent on the installation and service conditions and the flowline coating properties. These range from carbon steel clamp arrangements, using elastic materials such as titanium, rubber and GRP for insulated flowlines where the outer diameter of the thermal coatings can vary significantly during service.
Metallic Components
Metallic components materials are selected for both their mechanical performance and resistance to corrosion. Typical materials are Inconel, Super Duplex, Titanium and CP protected carbon steel.
Our Flowline Buoyancy Systems use steel and aluminium mould tooling processes and are manufactured on our sites in Skelmersdale, UK and Houston, Texas, USA.
Testing
Testing and product development are at the heart of our material advances and product solutions. Whether this be within laboratories, full scale testing or ongoing research and development, testing is a major focal point for us. We believe that continuous and extensive testing is the only way to remain at the forefront of material development and continue to offer solutions that expand production possibilities and improve operating efficiency.
Testing for our Flowline Buoyancy systems encompasses the following:
- Material testing
- Fit-up and assembly testing
- Load testing - axial, lateral and bending
- Hydrostatic testing
- Abrasial testing
- Weight and buoyancy measurement