Patent ID: 7690437

Claim:
A method of constructing a well comprising a borehole drilled through underground formations, the method comprising: positioning at least one device on the outside of the tubular string, the device being operable to move between first and second configurations; positioning a tubular string in the borehole with the device positioned in the annular space between the tubular string and the borehole wall in its first configuration so as to interact with the tubular string and the borehole while allowing borehole fluid to flow along the annular space and around the device; and applying a trigger to initiate expansion of the device between the first and second configurations operating the device so as to move it from its first configuration to expand into its second configuration in which it substantially fills at least part of the annular space so as to inhibit flow of fluids along the borehole in the space wherein expansion is initiated by irradiating the device with microwave or ultrasonic radiation.