Ring member for a swellable downhole packer

A ring member for a well string assembly comprising a well string section and a swellable wellbore packer section coupled together by a coupling arrangement,

• wherein the ring member is configured to form an annular abutment surface that cooperates with a swellable member disposed on a substantially cylindrical body of the swellable wellbore packer section,
• wherein the swellable member comprises a material selected to expand on exposure to at least one triggering fluid to create a fluid seal in a wellbore annulus;
• and
• wherein the ring member is further configured to be secured in the well string assembly via the coupling arrangement which couples the well string section and the swellable wellbore packer section when in use,
• wherein the ring member is secured to the body by a first threaded connection with a torque rating that exceeds the torque rating of a coupling between the well string section and another well string section.

An apparatus configured to form part of a well string, the apparatus comprising:

• a swellable wellbore packer section, comprising:
• a substantially cylindrical body having a swellable member disposed thereon, wherein the swellable member comprises a material selected to expand on exposure to at least one triggering fluid to create a fluid seal in a wellbore annulus, and wherein the body is configured to be coupled to a well string section by a coupling arrangement;
• and
• a ring member that forms an annular abutment surface that cooperates with the swellable member, secured to the well string via the coupling arrangement,
• wherein the ring member cooperates with the swellable member to provide centralization of the body or swellable member in the wellbore.

A method of forming a swellable packer on a well string, the method comprising the steps of:

• providing a swellable member on a substantially cylindrical body of the swellable packer, the swellable member comprising a material selected to expand on exposure to at least one triggering fluid to create a fluid seal in a wellbore annulus;
• providing a coupling arrangement for coupling the body to a well string section to form a well string assembly;
• securing a ring member in the well string such that the ring member forms an annular abutment surface that cooperates with the swellable member;
• and
• securing the ring member to the body by a first threaded connection with a torque rating that exceeds a torque rating of a coupling between a first well string section and a second well string section.