Wired or ported universal joint for downhole drilling motor

摘要

A bottom hole assembly for a drill string has a mud motor and a mandrel. The motor has a rotor and a stator, and the rotor defines a bore for passage of conductors. The mandrel has a bore for passage of the conductors and for drilling fluid, and rotation of the mandrel rotates a drill bit. A shaft and universal joints covert orbital motion at the rotor to rotational motion at the mandrel. To pass the conductors from a sonde uphole of the motor to electronics disposed with the mandrel, an inner beam disposes in a bore of the shaft. This inner beam has an internal passage for the conductors, and seal caps dispose on each end of the inner beam to seal inside the universal joints. The inner beam and seal caps prevent drilling fluid passing from the motor and around the shaft from communicating in the shaft's bore.

主权项

1. A bottom hole assembly for a drill string, comprising:
a mud motor disposed on the drill string and having a rotor and a stator, the rotor defining a first bore; a mandrel disposed downhole from the mud motor and defining a second bore; a shaft defining a third bore and having first and second ends, the first end coupled to the rotor with a first universal joint, the second end coupled to the mandrel with a second universal joint; and an inner beam disposed in the third bore of the shaft, the inner beam having an internal passage and having third and fourth ends, the third end sealing communication of the internal passage past the first end of the shaft at the first universal joint with the first bore of the rotor, the fourth end sealing communication of the internal passage past the second end of the shaft at the second universal joint with the second bore of the mandrel.