Abstract: The present invention relates to a method for cleaning and possibly sealing a subsurface well. According to the method a multichannel tool string comprising an adapter on a first end of the tool string, a guide device at the second end of the tool string are run into the well, whereupon the guide device is activated in order to permit the well to be flushed by the supply of fluid through at least one of the channels in connection with the tool string and fluids and particles from the well are transported back to the surface through at least one other of the channels in connection with the tool string. The invention also relates to a device for cleaning and possibly sealing a subsurface well.

Abstract: An apparatus for retaining and tensioning an end of a transmission line includes a nut element having internal threads configured to engage an externally threaded transmission line, such as an externally threaded coaxial cable, thereby retaining an end of the transmission line. The internal threads may form a passageway extending from a first end of the nut element to a second end of the nut element. This passageway may allow a transmission line to pass through the nut element. A socket may be incorporated into one end of the nut element to enable a tool to apply torque thereto. A corresponding method is also disclosed.

Abstract: A method of running a tubular string into a wellbore comprises running a bore-lining tubular string into a wellbore substantially without rotation, while rotating a cutting structure at a distal leading end of the tubular string. Other methods provide for rotation of the string and the provision of a non-rotating stabiliser towards the leading end of the string.

Abstract: A method of measuring dimensional changes in a transparent substrate includes forming an array of reference markers on a reference plate, forming an array of substrate markers on the transparent substrate, stacking the reference plate and transparent substrate such that the reference markers and substrate markers overlap, measuring coordinates of the substrate markers relative to coordinates of the reference markers before and after processing the transparent substrate, and determining dimensional changes in the transparent substrate from the difference between the measured relative coordinates of the substrate markers before and after processing the transparent substrate.