CUPROPRENE

Research has shown that concentrations of copper in seawater as low as 0.03mg/litre will prevent barnacle growth. Cupro-nickel alloys, therefore, are a preferred choice for the use in anti-fouling materials. The addition of Nickel greatly improves material strength, durability and controls the rate of corrosion - whilst the small iron content has a marked effect on erosion resistance in seawater with entrained particles. All this is achieved with the retention of bio-fouling properties which make cupro-nickel alloys the ideal choice for marine application.

Cuproprene consists of a monolayer of cupro-nickel granules (1mm diameter and 1mm long) embedded and chemically bonded into the surface of a 3mm thick Polychloroprene rubber sheet. The cupro-nickel alloy used by Dunlaw has excellent corrosion and anti-fouling properties as well as much higher erosion resistance than other 90/10 alloys as it contains iron rather than tin. The Polychloroprene is compatible with those employed for anti-corrosion coatings and is commonly used in marine environments.

Cuproprene is produced in belt form using a special process to uniformly distribute granules over the surface to give a cupro-nickel exposure in excess of 30%. After curing the strip is then coiled for ease of use.

Previous installations of Cuproprene include:

Trelleborg Kvitevjorn Project
(740 sq.m coverage for risers)

Hamilton Oil Company Ltd. - Liverpool Bay Project.
(700 sq.m coverage, of splash zone structural members and risers.)

ACT China - HZ Project
(90 sq.m coverage of 16" riser. )

Shell Auger - TLP Project
(96 sq.m coverage for rigid risers)


CUPROMARK

The Dunlaw "Cupromark" marine antifouling marker system was developed alongside its sister product Cuproprene in response to the Oil & Gas Industry's requirement, for long term underwater asset and apparatus identification. The Cupromark range of markers maximises effective use of diver ROV, AUV and DSV time, during inspection, repair and maintenance.

The markers can be installed on offshore steel or concrete structures, templates, manifolds, Xmas trees, wellheads, spoolpieces, pipelines, and umbilicals to name but a few.

The antifouling capability of Cupromark is the result of extensive testing and research for over 20 years.

In order to provide permanent subsea identification, markers must remain clear of marine growth throughout the lifetime of the offshore/subsea structure. This performance is achieved by exploiting the antifouling properties of copper.

Cupromark antifouling material consists of a monolayer of cupro-nickel granules (1mm dia and 1 mm long) embedded and chemically bonded into the surface of a 3 mm thick Polychloroprene rubber sheet. The copper nickel used has excellent corrosion and antifouling properties as well as higher erosion resistance than other 90/10 alloys. The bulk of the cupro-nickel remains below the surface of the marker and the antifouling effect continues at a controlled rate over many years.

Cupromark markers are pigmented in high visibility yellow (background) and black (character colour). Visibility tests carried out have proven this colour combination to the most effective, and this has been adopted as standard.

Specially developed installation systems are available for securing the markers, including vulcanising, cold bond adhesives and a variety of strapping systems.

Insulation

Dunlaw Engineering design and manufacture thermal insulation covers for a wide variety of Subsea applications primarily to minimise the potential of heat loss, especially on the sea bed. Whether it is a flexible jumper or flow line, Christmas tree, production equipment or wellhead, all susceptible to heat loss resulting in, at worst, blockages. Each piece has to be designed, based on operating temperatures, water depth, design life, with material selection a priority, E.g. PU or PU Foam, Syntactic and then subsequently individually made to fit frequently complex shapes

Various differently labelled and scaled markers

Installed marker using high-strength polymer strapping system