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A slip spool for selectively supporting or snubbing a tubing string suspended in a wellbore can be mounted to a wellhead. The slip spool has an axial passage to be aligned with the wellbore and at least two radial passages extending through a side wall of the slip spool and communicating with the ax

A slip spool for selectively supporting or snubbing a tubing string suspended in a wellbore can be mounted to a wellhead. The slip spool has an axial passage to be aligned with the wellbore and at least two radial passages extending through a side wall of the slip spool and communicating with the axial passage. At least two slip blocks are slidably supported within the respective radial passages. The slip spool further includes actuators for moving the respective slip blocks between an extended position in which they engage a component in the tubing string that provides a weight-bearing shoulder, and a retracted position in which the slip blocks clear the axial passage of the slip spool. The slip spool facilitates live well service operations and eliminates scoring of an exterior surface of the tubing.

대표청구항 ▼

A slip spool for selectively supporting or snubbing a tubing string suspended in a wellbore can be mounted to a wellhead. The slip spool has an axial passage to be aligned with the wellbore and at least two radial passages extending through a side wall of the slip spool and communicating with the ax

A slip spool for selectively supporting or snubbing a tubing string suspended in a wellbore can be mounted to a wellhead. The slip spool has an axial passage to be aligned with the wellbore and at least two radial passages extending through a side wall of the slip spool and communicating with the axial passage. At least two slip blocks are slidably supported within the respective radial passages. The slip spool further includes actuators for moving the respective slip blocks between an extended position in which they engage a component in the tubing string that provides a weight-bearing shoulder, and a retracted position in which the slip blocks clear the axial passage of the slip spool. The slip spool facilitates live well service operations and eliminates scoring of an exterior surface of the tubing. element assembly. 5. The apparatus of claim 1, wherein each said first shoe segment comprises: a body portion, wherein the body portion engages the packer mandrel when the retaining shoe is in the initial position; and a fin portion extending radially outwardly from the body portion for engaging one of the upper or lower ends of the packer element assembly, wherein the body portions of the first shoe segments define a body of the first shoe, and the fin portions of the first shoe segments define a fin of the first shoe. 6. The apparatus of claim 5, wherein the retaining shoe is an upper retaining shoe and the apparatus further comprises a lower retaining shoe, wherein the upper retaining shoe is disposed at the upper end of the packer element assembly and the lower retaining shoe is disposed at the lower end of the packer element assembly, the fin on the upper retaining shoe engages the upper end of the packer element assembly, and the fin on the lower retaining shoe engages the lower end of the packer element assembly. 7. The apparatus of claim 5, wherein the body generally defines a cylindrical shape when disposed about the packer mandrel, and the fin extends radially outwardly from the body. 8. The apparatus of claim 5, wherein an inner surface of the second shoe defines a generally truncated cone shape for engaging the fin of the first shoe. 9. The apparatus of claim 1, wherein each second shoe segment is affixed to a first shoe segment by gluing. 10. A retaining shoe for limiting the extrusion of a packer element assembly disposed about a packer mandrel, wherein the packer element assembly is movable from an unset position to a set position in a wellbore, and the packer element assembly seals the wellbore when moved to the set position, the retaining shoe comprising: a plurality of first shoe segments encircling the packer mandrel, wherein the first shoe segments define a sloped, arcuate inner surface for engaging an end of the packer element assembly, and adjacent ones of the first shoe segments have gaps therebetween; a plurality of second shoe segments disposed about the first shoe segments, where the second shoe segments define a sloped, arcuate inner surface for engaging a sloped arcuate outer surface of the first shoe segments, and adjacent ones of the second shoe segments have gaps therebetween wherein each second shoe segment is affixed to a first shoe segment; and wherein a width of the gaps between the first shoe segments and a width of the gaps between the second shoe segments increase when the packer element assembly moves from the unset position to the set position, and the first shoe segments cover the gaps between the second shoe segments and the second shoe segments cover the gaps between the first shoe segments. 11. The retaining shoe of claim 10, wherein the retaining shoe is movable from an initial position corresponding to the unset position of the packer element assembly, to an expanded position corresponding to the set position of the packer element assembly, the retaining shoe and the wellbore define a gap therebetween when the retaining shoe is in the initial position, and the retaining shoe engages the wellbore in the expanded position. 12. The retaining shoe of claim 11, wherein the first shoe segments engage the packer mandrel in the initial position and engage the wellbore in the expanded position, and the second shoe segments engage the wellbore in the expanded position. 13. The retaining shoe of claim 10, wherein each said first shoe segment comprises: a body portion; and a fin portion connected to the body portion, the fin portion sloping outwardly from the body portion. 14. The retaining shoe of claim 13, wherein the fin portion engages the wellbore in the expanded position. 15. The retaining shoe of claim 14, wherein each second shoe segment has an inner surface and an outer surface, the inner surface is configured to engage an outer surface of the fin portion and the b ody portion of the first shoe segments, and the outer surface of each second shoe segment engages the wellbore in the expanded position. 16. The retaining shoe of claim 13, wherein the first shoe segments define a first shoe and the second segments define a second shoe, the body portions of the first shoe segments define a body of the first shoe, the fin portions of the first shoe segments define a fin of the first shoe, the body has a generally cylindrical shape, and the fin extends radially outwardly from the body for engaging an end of the packer element assembly. 17. The apparatus of claim 10, wherein each second shoe segment is affixed to a first shoe segment by gluing. 18. A downhole apparatus for use in a wellbore, the apparatus comprising: a packer mandrel having an axial centerline; a packer element assembly disposed about the packer mandrel, wherein the packer element assembly has an upper end and a lower end and is movable from an unset position wherein the packer element assembly and the wellbore define an annular gap therebetween, to a set position wherein the packer element assembly sealingly engages the wellbore; an upper retaining shoe for axially retaining the packer element assembly, the upper retaining shoe comprising an upper inner retainer and an upper outer retainer, the upper inner retainer comprising: a generally cylindrical upper body disposed about the packer mandrel; and an upper fin connected to and extending radially outwardly from the upper body, wherein the upper fin engages the upper end of the packer element assembly, the upper outer retainer is disposed about the upper inner retainer, and the upper inner and upper outer retainers are movable from an initial position corresponding to the unset position of the packer element assembly wherein an annular gap exists between the upper retaining shoe and the wellbore, to an expanded position corresponding to the set position of the packer element assembly wherein the upper retaining shoe engages the wellbore wherein the upper inner retainer is comprised of a plurality of upper inner retainer segments, and wherein the upper outer retainer comprises a plurality of upper outer retainer segments, each upper inner retainer segment being affixed to an upper outer retainer segment; and a lower retaining shoe, the lower retaining shoe comprising a lower inner retainer and a lower outer retainer, the lower inner retainer comprising: a generally cylindrical lower body disposed about the packer mandrel; and a lower fin connected to and extending radially outwardly from the lower body, wherein the lower fin engages the lower end of the packer element assembly, the lower outer retainer is disposed about the lower inner retainer, and the lower inner and lower outer retainers are movable from the initial position corresponding to the unset position of the packer element assembly, to the expanded position corresponding to the set position of the packer element assembly. 19. The apparatus of claim 18, wherein adjacent ones of the upper inner retainer segments have gaps therebetween, and a width of the gaps between the adjacent upper inner retainer segments increases when the upper retaining shoe moves from the initial position to the expanded position; and adjacent ones of the upper outer retainer segments have gaps therebetween, a width of the gaps between the adjacent upper outer retainer segments increases when the upper retaining shoe moves from the initial position to the expanded position, and the upper outer retainer segments cover the gaps between the upper inner retainer segments and the upper inner retainer segments cover the gaps between the upper outer retainer segments. 20. The apparatus of claim 19, wherein the lower inner retainer further comprises: a plurality of lower inner retainer segments, wherein adjacent ones of the lower inner retainer segments have gaps therebetween, and a width of the gaps between the adjacent lower i