Universal joint

Patent metadata

Field	Value
Publication number	US-10619678-B2
Application number	US-201615160809-A
Country	US
Kind code	B2
Filing date	May 20, 2016
Priority date	May 22, 2015
Publication date	Apr 14, 2020
Grant date	Apr 14, 2020

Abstract

A universal joint assembled to a drill string transfers torque between two components where rotation of the components may not be completely aligned. The universal joint includes upper and lower longitudinal members each connected to opposite sides of a bearing element. The elements are connected to the bearing element at spaced radial positions. As the joint rotates the bearing element flexes between the connections to accommodate misalignment of the elements. Axial force can be transferred through the bearing element as well as torque.

First claim

The invention claimed is:

1. A universal joint assembly comprising:
a disk-shaped bearing element with opposite sides, and
two joint members connected to the bearing element at radially and angularly spaced positions to transmit torque with a joint member extending from each of the opposite sides of the bearing element;
wherein each joint member has an axis of rotation, a connector for joining to drill string components, and axially extending arms on an end opposite the connector with a recess between them,
wherein the bearing element further comprises a plurality of discs in an elastomer sleeve,
wherein the material of each disc of the plurality of discs comprises steel, copper alloys, nylon, ceramics, or combinations thereof, is configured to support a fixed non-zero angle of deflection between the axis of rotation of each joint member, and
wherein the axially extending arms of the two joint members connect to a periphery of the bearing element at radially and angularly spaced positions for transmitting torque between the joint members and are parallel to each and to the axis of rotation.

2. The universal joint assembly of claim 1 where the bearing element is generally flat.

3. The universal joint assembly of claim 1 where the bearing element includes a shim between an adjacent pair of the disks.

4. The universal joint assembly of claim 1 where the bearing element further includes slots and holes, wherein the holes and the slots have different shapes.

5. The universal joint assembly of claim 1 including a second bearing element between but separate from the joint members, and where each joint member includes a seat to contact the second bearing element on opposite sides to transfer axial force through the joint assembly.

6. The universal joint assembly of claim 5 where the second bearing element is a ball bearing.

7. An assembly to transfer loads between a mud motor and a bit comprising:
a mud motor and a bit; and
the universal joint assembly of claim 1 .

8. The assembly of claim 7 where the universal joint assembly comprises a ball bearing.

9. The assembly of claim 8 where the ball bearing has less than half the width of each joint member and the two joint members contact opposite sides of the ball.

10. The assembly of claim 7 , wherein the two joint members each have ends that are each slotted to define the at least two axially extending arms.

11. The universal joint assembly of claim 1 , wherein the two joint members each have ends that are each slotted to define the at least two axially extending arms.

12. The universal joint assembly of claim 1 , wherein the disk-shaped bearing element has defined through it a plurality of holes formed at angularly spaced positions, and each of the axially extending arms has an end adjacent to the disk-shaped bearing element, to which is a stud is attached that extends through the holes in the bearing element.

13. The universal joint assembly of claim 1 , wherein each of the plurality of discs includes an alignment mark therein.

14. The universal joint assembly of claim 1 , wherein the bearing element further comprises a lubricant.

15. A joint assembly to transfer torque in a downhole drill string comprising:
first and second bodies having adjacent ends with at least two axially extending connection portions, wherein the axially extending connection portions of each of the bodies form a recess between them, and wherein the axially extending connection portions having connectors extending therefrom that are parallel to each other and to the axis of rotation of each body;
at least one disk that is coupled to the connectors extending from the connection portions of each of the slotted ends on opposite sides at radially and angularly spaced positions so a portion of the at least one disk extends between connection portions of the bodies; and
a fatigue indicator disk having a reduced service life relative to the at least one disk;
wherein the at least one disk is configured to support a fixed non-zero angle of deflection between the axis of rotation of the first body and the axis of rotation of the second body.

16. The joint assembly of claim 15 where the at least one disk flexes between the connection portions to absorb misalignment of the first and second bodies.

17. The joint assembly of claim 15 where the at least one disk includes openings at spaced positions, and studs on the slotted ends of the first and second bodies pass through openings in the at least one disk.

18. The joint assembly of claim 17 where the openings are slots and over-torque of the joint is indicated by relative radial movement of the studs in the slots.

19. The joint assembly of claim 17 including openings in the at least one disk, bushings received in the openings, and fasteners in the bushings to couple the bodies to the at least one disk.

20. The joint assembly of claim 15 , wherein the fatigue indicator disk has a service life that is about 80% of the service life of the at least one disk.

21. A universal joint assembly of a drill string comprising:
a disk-shaped bearing element with opposite sides with a plurality of holes formed through it at angularly spaced positions;
two joint members connected to the disk-shaped bearing element at angularly spaced positions, the joint members configured to transmit torque with one joint member extending from each of the opposite sides of the disk-shaped bearing element; and
a ball-shaped bearing element between the two joint members, the ball-shaped bearing element comprising chrome steel, stainless steel, or ceramic,
wherein the disk-shaped bearing element comprises a plurality of disks in an elastomer sleeve, the material of each disc of the plurality of disks comprises steel, copper alloys, nylon, ceramics, or combinations thereof,
wherein the disk-shaped bearing element further comprises a fatigue indicator disk having a reduced service life relative to the plurality of disks,
wherein each joint member has a connector at one end for joining to drill string components, an axis of rotation, and axially extending arms with a recess between them that are substantially parallel to each other and the axis of rotation where they join the disk-shaped bearing element, each arm including a stud that extends from the arm and extends through one of the plurality of holes in the disk-shaped bearing element to connect the axially extending arm to a periphery of the bearing element at radially and angularly spaced positions for transmitting torque between the joint members, and
wherein the disk-shaped bearing element is configured to support a fixed non-zero angle of deflection between the axis of rotation of each joint member.

22. The universal joint assembly of claim 21 further comprising a sleeve sealing to the two joint members.

23. The universal joint assembly of claim 21 , further comprising an overstress indicator.

24. The universal joint assembly of claim 21 , wherein the disk-shaped bearing element further comprises a lubricant.

Assignees

• Ulterra Drilling Tech Lp

Inventors

• Kummer Nikolai
• St Pierre Beau J
• Maw Jason

Classifications

• E21B17/03

  between drilling rod or pipe and drill motor {or surface drive}, e.g. between drilling rod and hammer · CPC title

• F16D3/79 Primary

  the disc or ring being metallic · CPC title

• E21B4/006

  Mechanical motion converting means, e.g. reduction gearings (E21B4/10 takes precedence) · CPC title