초록 ▼

A directional drilling “sub”provides a shifting end portion which allows the sub to be rotated from a first in-line axially straight orientation with the drill string to a second angled or “bent”position which second position is normally associated with conventional bent “subs”which are permanently

A directional drilling “sub”provides a shifting end portion which allows the sub to be rotated from a first in-line axially straight orientation with the drill string to a second angled or “bent”position which second position is normally associated with conventional bent “subs”which are permanently structured in the bent position. The device shifts from the first (in-line) position to the second (bent) position upon the application of torsional force thereto which torsional force can be applied, for example, by the actuation of a “turbodrill”(normally attached thereto in operation). The device can be manufactured or machined to provide varying angles to the sub in its bent position to satisfy differing directional drilling situations. The axially aligned first position allows easy entry of the drill string, sub, and turbodrill into the well hole, while the second bend position is used to commence directional drilling. The sub will return gradually to its original axially aligned position when the device is withdrawn from the wellhole, as such position is the path of minimum resistance for the withdrawing drill string and torsion is not present to hold the sub in the bent position.

대표청구항 ▼

A method of directional drilling using a rotatable drilling means and drill string comprising the steps of: (a) providing a directional drilling sub, which sub comprises: (i) a tool body; (ii) first connection means on said tool body for attaching said tool body to a drill string; (iii) second conne

A method of directional drilling using a rotatable drilling means and drill string comprising the steps of: (a) providing a directional drilling sub, which sub comprises: (i) a tool body; (ii) first connection means on said tool body for attaching said tool body to a drill string; (iii) second connection means on said tool body for attaching a rotating drilling means to said tool body; and (iv) shifting means associated with said tool body for forming an angular deviation between said first and said second connection means, said deviation producing a deviating angle between a drill string attached to said tool body and a rotating drilling means attached to said tool body; (b) attaching the sub to the drill string at said first connection means; (c) attaching the drilling means to the sub at said second connection means; (d) providing the sub in a first position which substantially aligns the central axes of the drill string and drilling means; (e) lowering the axially aligned drill string and drilling means with the attached sub into a well hole; (f) actuating the rotatable drilling means to produce a torsion in the sub to effect a shifting of the sub to a second, angularly deviated position which produces a deviating angle between the axes of the drill string and the drilling means; and (g) directionally drilling with the drilling means.