18344005 A description fig1 is a section view showing an open hole wellbore 40 the wellbore 40 includes a central wellbore which is lined with casing 42 the annular area between the casing 42 and the earth is filled with cement 46 as is typical in well completion extending downward from the central well bore is an open hole wellbore 48 a formation 50 is shown adjacent the well bore 48 disposed in the open wellbore 48 is a downhole tool 20 to be expanded in the embodiment shown in fig1 the tool 20 is an expandable sand screen ess u2019 u201d however the tool 20 could be any expandable downhole apparatus an ess 20 is hung within the wellbore 40 from a hanging apparatus 32 in some instances the hanging apparatus is a packer not shown in the depiction of fig1 the hanging apparatus is a liner 30 and liner hanger 32 a separate packer 3 4 may be employed to seal the annulus between the liner 30 and the production tubular 44 also depicted in fig1 is an encapsulation 10 of the present invention the encapsulation 10 is shown running from the surface to the liner hanger 32 the encapsulation 10 is secured to the production tubular 44 by clamps shown schematically at 18 clamps 18 are typically secured to the production tubular 44 approximately every ten meters the clamps 18 are designed to expand with the tool.