Multi-Directionally Rotating Downhole Drilling Assembly and Method

摘要

Embodiments of a downhole drilling assembly generally include a rotatable lower drilling assembly, a rotatable upper drilling assembly, and a drill bit, wherein the upper drilling assembly contains a mud motor adapted for clockwise rotation of its stator and counter-clockwise rotation of its rotor, whereby the lower drilling assembly is rotatable in the opposite direction of the upper drilling assembly or maintainable in a non-rotating state. The apparatus further includes sensors adapted to continuously measure physical properties and/or drilling parameters and a mechanism for continuously transmitting information relating thereto to the surface.;Embodiments of a method for operating a downhole drilling assembly generally include continuously measuring physical properties and/or drilling parameters proximate the drill bit, continuously transmitting information relating thereto to the surface, and controlling rotation of a lower drilling assembly in a non-rotating state or in the opposite direction of an upper drilling assembly by varying drill string rotation.

主权项

1. A downhole drilling assembly for use in a subsurface wellbore, comprising:
a rotatable lower drilling assembly; a rotatable upper drilling assembly; and a drill bit; wherein:
said lower drilling assembly comprises:
a first motor adapted to provide rotational force to said drill bit in a first direction; anda sensor assembly comprising one or more sensors; andsaid upper drilling assembly comprises:
a second motor adapted to provide rotational force to said lower drilling assembly in a second direction; wherein:said upper drilling assembly is adapted to provided rotational force directed in said first direction and rotational force directed in said second direction to said lower drilling assembly; andsaid lower drilling assembly is adapted to be rotated, by said rotational force directed in said first direction and said rotational force directed in said second direction, in one or more rotation modes selected from the group consisting of:
rotating in said first direction;rotating in said second direction; andnot rotating.