Balmoral Elastotherm™ and Balmoral Supatherm™
Subsea pipelines, flowlines, risers and associated equipment carrying high temperature hydrocarbons must be insulated to prevent cooling and solidifying during the flow process.
A number of high performance insulation coatings are available for direct application to flowline bends and straights, either within coating plants for straight joints or on-site/in-field for bends, spools, manifolds and ‘trees’. However, bends and connections between flowlines and subsea equipment can form cold spots unless also properly insulated. Balmoral’s range of Elastotherm and Supatherm products help maintain overall flow assurance.
Using static or transient finite element analysis, Balmoral designs insulation covers tailored to match either a project’s required overall heat transfer coefficient or design ‘cool down’ time. The BOE field-proven radial, axial sealing system for insulation covers helps prevent excessive water movement from within the insulation covers to the outside environment.
As insulation shells are flooded during service the key requirement of the materials used in their construction is that they must be able to tolerate lifetime exposure to hot/wet service conditions.
Hydrolytic sensitivity essentially precludes some established flowline ‘wet’ insulation products, eg, GSPU with its temperature tolerance of <60°C, and severely limits the service range of others, ie, PPG polyurethane systems which are limited to max 65-70°C. The majority of Balmoral’s Elastotherm range show good/excellent hot/wet tolerance, whilst three systems, Elastotherms HT-R, HT-F and S, have hot/wet tolerance to more than 120°C.
All Balmoral Elastotherm insulation systems provide outstanding insulation cover performance. The choice of grade should be made based on depth rating (all systems other than Elastotherm SPU have ‘unlimited’ capability); hot/wet service temperature (Elastotherm portfolio covers 65>135°C) and thermal conductivity, (Elastotherm portfolio covers 0.10>0.195W/m.°K). Details of individual grades are shown here.
Where combinations of otherwise-conflicting performances are required Balmoral offers its unique ‘layered shell’ system. This allows, for example, extreme temperature tolerance to be combined with outstanding impact protection.
The covers can be designed to be mounted onboard the offshore construction vessel or installed subsea by either a diver or remotely operated vehicle. The cover mounting procedure and closure system must be safe, fast and easy, requiring the minimum number of standard tools.
The Elastotherm product range is, as the name suggests, elastomeric in nature; the majority are also solid polymers. These properties limit the available insulation properties as none can be produced in syntactic form without compromising the hydrothermal degradation resistance as with GSPU.
Balmoral Supatherm is a glass syntactic foam system based on a hydrolytically-stable, aromatic amine-cured high Tg epoxy resin that was originally developed to provide insulation performance in water-flooded systems used on hybrid riser towers (HRT).
The properties which make Supatherm an outstanding HRT thermal insulation material provide similar benefits when used in flange insulation shells.
Layered shell system: The Balmoral Elastotherm HT (yellow) acts as a thermal barrier to protect the Balmoral Elastotherm outer (orange) against extreme high temperatures.