forage multibranche

OBS: Forage multidirectionnel réalisé à partir d'un trou pilote.
OBS: forage multibranche : proposition d'un ingénieur, Institut français du pétrole; nous avons trouvé l'expression «puits multibranche» dans un site Internet (justification reproduite ci-après).
OBS: forage en faisceaux : proposition faite à partir de l'expression «faisceaux de pipelines» relevée dans un site Internet (justification reproduite ci-après); approuvée par l'Institut français du pétrole, nov. 2002.

CONT: The exploration department at Cogema Resources ... recognized the technical difficulties and expense encountered in drilling deep vertical holes. The solution was a technique called navigational drilling (or Navi-drilling) that was used in the oil industry and, less often, in mining. ... Simply put, navi-drilling allows operators to begin drilling a new hole 500 to 600 metres below the surface by using a pre-existing ""pilot hole."" This significantly reduces costs as the same hole is used for up to six navi-drilling holes. A steerable motor with a rotor system turns a cutting bit. The motor is powered by hydraulic force created by the mixture of water and drilling muds pumped inside the drill string. The fluid is pumped through the motor and returns to the surface at a rate of up to 250 litres per minute. [Followed by an illustration of a schematic cross-section showing navi-drilling holes.]
CONT: Further deep drilling at Southwest Oyu will await the arrival of navigational drilling equipment, which will allow Ivanhoe to more accurately delineate the deeper portions of the high grade porphyry zone (in excess of one half of a mile deep).
CONT: Newbergh Industries Limited (""Newbergh"") has developed and patented a technology which will greatly enhance the steering currently being used in oil and gas field directional drilling. This technology, which is known under the acronym of ""HANDS"", which stands for Hydraulic Activated Navigational Drilling System, will be incorporated in a so-called benthousing, which will make this piece of equipment remote adjustable whilst drilling for the first time. Its implication will improve drilling performance in terms of speed as well as quality and will result in considerable cost savings for the oil companies and savings in energy to drill the bore holes.