Abstract: A depth measurement system for determining an absolute depth of a drill string uses a position acquisition device to determine a length value for a joint or stand being added to the drill string. The position acquisition device receives a signal from a target object associated with the added joint. The processed signal can be an optical signal, a radio signal, an acoustic signal, or other suitable signal. Using techniques such as time lapse, Doppler effect or phase shift, the depth measurement system determines a position parameter such as distance or position based on the received signal. Thereafter, the processor determines the absolute depth of the drill string by summing a length of each joint making up the drill string and correcting for the position of the newly added joint.

Abstract: A depth measurement system for determining an absolute depth of a drill string uses a position acquisition device to determine a length value for a joint or stand being added to the drill string. The position acquisition device receives a signal from a target object associated with the added joint. The processed signal can be an optical signal, a radio signal, an acoustic signal, or other suitable signal. Using techniques such as time lapse, Doppler effect or phase shift, the depth measurement system determines a position parameter such as distance or position based on the received signal. Thereafter, the processor determines the absolute depth of the drill string by summing a length of each joint making up the drill string and correcting for the position of the newly added joint.

Abstract: A fixture for mounting external cladding in the form of single facing sheets on internal or external walls of buildings includes a fixing bracket for affixation to a wall and a horizontal positioning plate to support the external cladding sheet. The horizontal positioning plate includes guides which hold the facing sheet in place. The fixture is horizontally and vertically adjustable. The horizontal positioning plate and the fixing bracket have substantially horizontal support surfaces that engage each other and are horizontally adjustable in all directions relative to one another. The horizontal supporting plate is locked in a selected position to the fixing bracket by a welded connection after the horizontal positioning plate has been adjusted relative to the fixing bracket.