Downhole apparatus with packer cup and slip

1. A downhole apparatus for use in a well bore, the apparatus comprising:

a center mandrel;

slip means disposed on the center mandrel for grippingly engaging an inner surface of the well bore when in a set position;

a retractable packer cup disposed on the center mandrel for selectively sealing an annulus between the center mandrel and the well bore, the retractable packer cup being releasably coupled to the center mandrel, the retractable packer cup is slidable relative to the center mandrel when released so as to permit the expansion of an elastomeric lip portion to sealingly engage the well bore; and

an o-ring that extends around the center mandrel for preventing the flow of fluid between the center mandrel and the retractable packer cup;

wherein the retractable packer cup seals the annulus prior to setting the slip means in the set position for engaging the well bore.

2. The apparatus of claim 1 , wherein at least one of the center mandrel and slip means is at least partially made of a non-metallic material.

3. The apparatus of claim 1 , further comprising:

an extrusion limiter at least partially disposed about the elastomeric lip portion of the retractable packer cup.

4. The apparatus of claim 1 , further comprising a lip sleeve attached to the retractable elastomeric lip portion.

5. The apparatus of claim 4 , further comprising at least one locking dog for securing the lip sleeve in place relative to the center mandrel.

6. The apparatus of claim 5 , wherein the at least one locking dog includes at least one soluble locking dog.

7. The apparatus of claim 1 , wherein the slip means comprises a generally cylindrical body having a dual-axis bore passage.

8. The apparatus of claim 1 , wherein the slip means comprises a wedge slip assembly, the wedge slip assembly comprising at least one slip segment.

9. A downhole assembly for use in a well bore, said assembly comprising:

a downhole apparatus comprising:

a center mandrel;

a slip means disposed on the center mandrel for grippingly engaging an inner surface of the well bore when in a set position;

a retractable packer cup disposed on the mandrel for selectively sealing an annulus between the mandrel and the well bore, the retractable packer cup being releasably coupled to the center mandrel, the retractable packer cup is slidable relative to the center mandrel when released so as to permit the expansion of an elastomeric lip portion to sealingly engage the well bore; and

an o-ring that extends around the center mandrel for preventing the flow of fluid between the center mandrel and the retractable packer cup;

wherein the retractable packer cup seals the annulus prior to setting the slip means in the set position for engaging the well bore;

a setting apparatus connected to the downhole apparatus for at least partially supporting the downhole apparatus while the downhole apparatus is lowered into the well bore.

10. The assembly of claim 9 , the center mandrel comprising:

a connecting portion; and

wherein the setting apparatus is connected to the connecting portion of the center mandrel.

11. The assembly of claim 10 , wherein the setting apparatus is connected to the connecting portion via at least one shear pin.

12. The assembly of claim 11 , wherein the setting apparatus includes an at least substantially sealed chamber filled with fluid having a predetermined pressure.

13. The assembly of claim 9 , wherein:

the retractable packer cup comprises:

a lip sleeve attached to the retractable elastomeric lip portion;

the downhole apparatus further comprising:

at least one locking dog for securing the lip sleeve in place relative to the mandrel; and

the setting apparatus comprises:

an index sleeve disposed around at least a portion of the mandrel;

an index slot formed in the index sleeve; and

an index pin extending at least partially into the index slot.

14. The assembly of claim 13 , wherein the index sleeve further comprises:

a locking dog release slot.

15. A method for setting a downhole tool in a wellbore, the method comprising:

lowering the downhole tool into the well, the downhole tool comprising a center mandrel, slip means disposed on the center mandrel, and a retractable packer cup disposed on the center mandrel in an unset position;

sealing an annulus between the mandrel and the well bore by selectively releasing the retractable packer cup from the center mandrel, the retractable packer cup having an elastomeric lip portion configured to urge radially outward in a relaxed set position, so as to contact and seal against the wellbore; and

creating a differential pressure across the retractable packer cup sufficient for causing the set retractable packer cup to slide relative to the center mandrel towards the slip means such that the slip means moves to a set position,

wherein the slip means is configured for grippingly engaging an inner surface of the well when in the set position; and

wherein the retractable packer cup is configured to retract prior to being set in the set position.

16. The method of claim 15 , further comprising:

supporting the downhole tool with a setting apparatus as the downhole tool is lowered into the well; and

detaching the setting apparatus from the downhole tool after the slip means is moved to the set position, wherein the detaching of the setting apparatus includes applying a force to the setting apparatus suitable for shearing at least one shear pin.

17. The method of claim 15 , further comprising:

supporting the downhole tool with a setting apparatus as the downhole tool is lowered into the well, wherein the setting apparatus includes an at least substantially sealed chamber filled with fluid having a predetermined chamber pressure; and

detaching the setting apparatus from the downhole tool after the slip means is moved to the set position, wherein the detaching of the setting apparatus includes increasing a head pressure external to the setting tool at least until the head pressure exceeds the chamber pressure by a predetermined amount.

18. The method of claim 15 , further comprising:

supporting the downhole tool with a setting apparatus as the downhole tool is lowered into the well, wherein the setting apparatus includes an index sleeve and the packer cup is a retractable packer cup;

after the downhole tool is lowered into the well, rotating the index sleeve until the retractable packer cup is free to retract; and

detaching the setting apparatus from the downhole tool after the slip means is moved to the set position.