Tangentially-loaded high-load retrievable slip system

Abstract

A slip system includes a set of drive slips having wickers thereon, substantially all of which being truncated in cross-section; a set of gripping slips operatively interengagable with the set of drive slips; a drive slip end ring in operable communication with the set of drive slips; and a gripping slip end ring in operable communication with the set of gripping slips, the end rings capable of transmitting a load applied in an axial direction of the system to the set of gripping slips and the set of drive slips to tangentially load the set of drive slips and the set of gripping slips against each other thereby increasing a radial dimension of the system and distributing stresses created in a target tubular and method.

The invention claimed is: 
     
       1. A slip system comprising:
 a set of drive slips having wickers thereon, all of which being truncated in cross-section; 
 a set of gripping slips operatively interengagable with the set of drive slips; 
 a drive slip end ring in operable communication with the set of drive slips; and 
 a gripping slip end ring in operable communication with the set of gripping slips, the end rings capable of transmitting a load applied in an axial direction of the system to the set of gripping slips and the set of drive slips to tangentially load the set of drive slips and the set of gripping slips against each other thereby increasing a radial dimension of the system and distributing stresses created in a target tubular. 
 
     
     
       2. The slip system as claimed in  claim 1  wherein the wherein the drive slips engage only frictionally with a target tubular. 
     
     
       3. The slip system as claimed in  claim 1  wherein the truncation is by an amount about the same as an amount a sharp wicker having similar dimensions and flank angles would be expected to penetrate a target tubular. 
     
     
       4. The slip system as claimed in  claim 1  wherein the gripping slips possess at least one truncated wicker. 
     
     
       5. The slip system as claimed in  claim 1  wherein the gripping slips possess a plurality of truncated wickers. 
     
     
       6. The slip system as claimed in  claim 5  wherein the truncated wickers are positioned on each gripping slip to distribute applied stress in a target tubular. 
     
     
       7. The slip system as claimed in  claim 5  wherein the truncated wickers are positioned on each gripping slip in an alternating pattern with sharp wickers. 
     
     
       8. The slip system as claimed in  claim 7  wherein the pattern is a single alternating pattern. 
     
     
       9. The slip system as claimed in  claim 7  wherein the pattern is a double alternating pattern. 
     
     
       10. The slip system as claimed in  claim 7  wherein the pattern is a triple alternating pattern. 
     
     
       11. The slip system as claimed in  claim 7  wherein the pattern is a random pattern of truncated and sharp wickers. 
     
     
       12. The slip system claimed in  claim 1  wherein the drive end ring includes a plurality of interengagement slots. 
     
     
       13. The slip system as claimed in  claim 12  wherein the slots are all the same dimensions and shape. 
     
     
       14. The slip system as claimed in  claim 12  wherein the slots are T-shaped. 
     
     
       15. The slip system as claimed in  claim 1  wherein the grip end ring includes a plurality of interengagement slots. 
     
     
       16. The slip system claimed in  claim 1  wherein each slip of the set of slips includes a keyed flange and a flange keyhole. 
     
     
       17. A method for distributing stress in a target tubular imparted by a slip system as claimed in  claim 1  comprising:
 embedding a plurality of sharp wickers of the slip system into the target tubular; and 
 contacting an inside dimension of the target tubular with a plurality of truncated wickers. 
 
     
     
       18. A slip system comprising:
 a set of drive slips having wickers thereon, substantially all of which being truncated in cross-section and wherein the drive slips engage only frictionally with a target tubular; 
 a set of gripping slips operatively interengagable with the set of drive slips; 
 a drive slip end ring in operable communication with the set of drive slips; and 
 
       a gripping slip end ring in operable communication with the set of gripping slips, the end rings capable of transmitting a load applied in an axial direction of the system to the set of gripping slips and the set of drive slips to tangentially load the set of drive slips and the set of gripping slips against each other thereby increasing a radial dimension of the system and distributing stresses created in a target tubular. 
     
     
       19. A slip system comprising:
 a set of drive slips having wickers thereon, all of which being truncated in cross-section; 
 a set of gripping slips operatively interengagable with the set of drive slips; 
 a drive slip end ring in operable communication with the set of drive slips; and 
 
       a gripping slip end ring having a plurality of interengagement slots of differing dimensions, the gripping end ring in operable communication with the set of gripping slips, the end rings capable of transmitting a load applied in an axial direction of the system to the set of gripping slips and the set of drive slips to tangentially load the set of drive slips and the set of gripping slips against each other thereby increasing a radial dimension of the system and distributing stresses created in a target tubular. 
     
     
       20. A slip system comprising:
 a set of drive slips having wickers thereon, all of which being truncated in cross-section; 
 a set of gripping slips operatively interengagable with the set of drive slips; 
 a drive slip end ring in operable communication with the set of drive slips; and 
 
       a gripping slip end ring having a plurality of interengagement slots configured to selectively load in tension certain ones of the set of gripping slips, the gripping end ring in operable communication with the set of gripping slips the end rings capable of transmitting a load applied in an axial direction of the system to the set of gripping slips and the set of drive slips to tangentially load the set of drive slips and the set of gripping slips against each other thereby increasing a radial dimension of the system and distributing stresses created in a target tubular. 
     
     
       21. A slip system for anchoring a body to a surrounding tubular at a subterranean location, comprising:
 a body;   at least one drive slip with a truncated wicker cross-section on said body that does or do not penetrate the surrounding tubular;   at least one gripping slip on said body operatively interengagable with said drive slip for relative axial movement therebetween, said gripping slip penetrates the surrounding tubular;   said relative movement creating tangential loading between said set of drive slips and said set of gripping slips thereby increasing a radial dimension of the system for support of said body from the surrounding tubular and to distribute stresses created in the surrounding tubular.   
     
     
       22. The system of claim 21, wherein:
 said truncated wicker cross-section comprises an outer surface that prevents further penetration of the surrounding tubular by said gripping slip when said outer surface engages the surrounding tubular.   
     
     
       23. The system of claim 21, wherein:
 said radial dimension of said system is decreased by initial movement of said drive slip.   
     
     
       24. The system of claim 23, wherein:
 said gripping slip engaged to a gripping slip actuator with a lost motion feature to allow a drive slip actuator to initially axially move said drive slip before said gripping slip is moved.   
     
     
       25. The system of claim 21, wherein:
 said drive member and said gripping member move in opposed directions.   
     
     
       26. The system of claim 21, wherein:
 said drive slip and said gripping slip each have integrated edge configurations that interlock for slidable movement to change the dimension of the system.   
     
     
       27. The system of claim 21, wherein:
 said drive slip frictionally engages the surrounding tubular.   
     
     
       28. The system of claim 21, wherein:
 said gripping slip comprises at least one sharp wicker.   
     
     
       29. The system of claim 28, wherein:
 said gripping slip comprises at least one truncated wicker.   
     
     
       30. A slip system comprising:
 a set of drive slips that engage only frictionally with a target tubular;   a set of gripping slips operatively interengagable with the set of drive slips;   a drive slip end ring in operable communication with the set of drive slips; and   a gripping slip end ring in operable communication with the set of gripping slips, the end rings capable of transmitting a load applied in an axial direction of the system to the set of gripping slips and the set of drive slips to tangentially load the set of drive slips and the set of gripping slips against each other thereby increasing a radial dimension of the system and distributing stresses created in a target tubular.   
     
     
       31. A slip system comprising:
 a set of drive slips that engage only frictionally with a target tubular;   a set of gripping slips operatively interengagable with the set of drive slips;   a drive slip end ring in operable communication with the set of drive slips; and   a gripping slip end ring having a plurality of interengagement slots of differing dimensions, the gripping end ring in operable communication with the set of gripping slips, the end rings capable of transmitting a load applied in an axial direction of the system to the set of gripping slips and the set of drive slips to tangentially load the set of drive slips and the set of gripping slips against each other thereby increasing a radial dimension of the system and distributing stresses created in a target tubular.   
     
     
       32. A slip system comprising:
 a set of drive slips that engage only frictionally with a target tubular;   a set of gripping slips operatively interengagable with the set of drive slips;   a drive slip end ring in operable communication with the set of drive slips; and   a gripping slip end ring having a plurality of interengagement slots configured to selectively load in tension certain ones of the set of gripping slips, the gripping end ring in operable communication with the set of gripping slips the end rings capable of transmitting a load applied in an axial direction of the system to the set of gripping slips and the set of drive slips to tangentially load the set of drive slips and the set of gripping slips against each other thereby increasing a radial dimension of the system and distributing stresses created in a target tubular.