The need to operate at greater depths and with longer subsea tiebacks has spurred the development of flowline and riser insulation that is lighter, stronger and offers lower heat transfer.
The high strength and low thermal conductivity (0.06 to 0.2 WŸm-1Ÿ K-1@ 20ºC) of 3M glass bubbles make them ideal additives for use in many wet pipeline and riser insulation applications.
Subsea Flowlines -- Conventional flowline constructions, such as "pipe-in-pipe," are proving to be impractical and too costly for use at today's greater depths of 10,000 ft (3,000 m) and more. Although pipe-in-pipe offers the best U-value (insulating value) and longest cool-down times, the added weight and bulk of its construction can make it more difficult and costly to lay, and too heavy to support in deeper waters, of particular concern for risers.
As an alternative, flexible flowlines -- consisting of a single pipe coated with 3M glass bubble-filled syntactic foam insulation -- is less than half the weight of pipe-in-pipe, making it more practical for use at greater depths and in longer runs. Because this construction reduces overall pipeline diameter, more pipe can be wound per spool, requiring fewer and smaller ships -- making installation faster, easier and more economical. Because of these and many other factors, wet pipe insulation now accounts for the majority of all new deep water subsea flowlines. Compared with the standard 3M glass bubble range of products, the XLD range of 3M glass bubbles allows thinner insulation on flexible flowlines with the same insulation performance which enables even more pipe on a reel.
Production Risers – The industry trend for deeper offshore oil production platforms has driven increasing use of wet insulation syntactic foam coatings made with 3M glass bubbles on Steel Caternary Risers (SCRs), Top-Tensioned Risers (TTRs) and riser towers, to achieve OHTC (U values) of 2 W/m^2 K and below.
3M™ Glass Bubbles for High Performance Syntactic Foams
The ideal combination of high strength and low density has made 3M™ Glass Bubbles an industry-standard additive for syntactic foams used in buoyancy modules, buoys or buoyancy blocks for undersea vehicles. When 3M glass bubbles are formulated with resin, the resultant syntactic foam has a high strength-to-density ratio to provide maximum net buoyancy for a given depth rating.
3M™ Glass Bubbles have pressure ratings ranging from 250 psi to 27,000 psi and average true densities ranging from 0.125 g/cc to 0.60 g/cc. When incorporated into syntactic foams, they can be used in applications such as:
Find out how 3M glass bubbles can help expand the capabilities of your oil and gas operations in these key areas:
Buoyancy modules - On drill risers, buoyancy modules that incorporate the use of 3M glass bubbles help prevent the steel casing from collapsing under its own weight at depth, and protect the drill string against ocean currents.
Distributed Buoyancy Modules (DBMs) – Syntactic foam DBMs made with 3M glass bubbles enable the formulation of foams with maximum lift at the required ocean depth.
Buoyancy blocks for Remote Operated Vehicles (ROVs) – On ROVs, syntactic foams made with 3M glass bubbles allow for high net buoyancy foams rated to any ocean depth.