Magni CFW (Crushable Foam Wrap)

Magni CFW (Crushable Foam Wrap)

Trelleborg’s Magni CFW is designed to be installed around the inner drill casing which is then immersed within the annulus fluid. As the pressure of the annulus fluid increases, the CFW will collapse at a pre-determined pressure/temperature combination, allowing expansion of the annulus fluid and dispersing any potentially destructive pressure increases.

Honeycomb microstructure

Polymeric CFW has a honeycomb microstructure which allows compression of the foam to take place. There are currently 12 approved  grades of CFW, covering a wide range of temperatures and pressures.

Tailored structure 

The structure is tailored to fail at the required pressure or temperature combination as dictated by the well conditions.

Flexible positioning

CFW may be placed anywhere within the trapped annulus and still allow the free flow of the liquid. Bespoke tooling can be manufactured to cater for any pipe configuration or subsea architecture.

Guaranteed performance

CFW's polymeric nature means that the foam itself has a thermal softening point, formulated to be below the maximum operating temperature of the annulus, ensuring the foam cannot fail to collapse before the maximum operating temperature is reached.

Key Applications

Inner drill casing


View Magni CFW

product sheet
crushable foam wrap

Magni CFW (Crushable Foam Wrap)