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An apparatus and method for operating a packer and a fracture valve. The packer may include a tubular mandrel having a longitudinal bore with an annular packing element and a first piston disposed around the mandrel, wherein the first piston is operable to set the packing element, and a second pisto

An apparatus and method for operating a packer and a fracture valve. The packer may include a tubular mandrel having a longitudinal bore with an annular packing element and a first piston disposed around the mandrel, wherein the first piston is operable to set the packing element, and a second piston operable to isolate fluid communication between the first piston and the mandrel bore. The fracture valve may include a tubular mandrel having a longitudinal bore and a port, a piston operable to close fluid communication between the bore and the port, and a latch disposed between the piston and the mandrel operable to resist movement of the piston.

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1. A valve for injecting fluid into a wellbore, comprising: a tubular mandrel having a bore formed therethrough and a port formed through a wall thereof;a piston axially moveable relative to the mandrel between a first position where the piston substantially seals the bore from the port and a second

1. A valve for injecting fluid into a wellbore, comprising: a tubular mandrel having a bore formed therethrough and a port formed through a wall thereof;a piston axially moveable relative to the mandrel between a first position where the piston substantially seals the bore from the port and a second position where the bore is in fluid communication with the port, wherein the piston is movable from the first position to the second position using pressurized fluid at a first pressure, and wherein the piston automatically returns to the first position when the pressurized fluid is at a second pressure that is less than the first pressure; anda latch disposed between the piston and the mandrel, the latch operable to resist movement of the piston relative to the mandrel by engaging a first tapered surface when moved from the first position to the second position and by engaging a second tapered surface when moved from the second position to the first position, wherein the first and second tapered surfaces are disposed on one of the mandrel and the piston, wherein the first tapered surface has an angle greater than an angle of the second tapered surface. 2. The valve of claim 1, wherein the latch is disposed on one of the piston and the mandrel, and the first tapered surface and the second tapered surface are formed on the other one of the piston and the mandrel, and wherein the latch engages the first tapered surface when the piston is in the first position and engages the second tapered surface when the piston is in the second position. 3. The valve of claim 1, wherein the latch comprises at least one of a c-ring and a collet coupled to the piston. 4. The valve of claim 1, wherein the latch abuts the first tapered surface having an angle between 80 degrees and 20 degrees formed on the mandrel, when the latch is in the first position. 5. The valve of claim 4, wherein the latch abuts the second tapered surface having an angle between 20 degrees and 5 degrees formed on the mandrel, when the latch is in the second position. 6. The valve of claim 5, wherein the piston is operable to force the latch over the first tapered surface at a first force. 7. The valve of claim 6, wherein the piston is operable to force the latch over the second tapered surface at a second force. 8. The valve of claim 7, wherein the first force is greater than the second force. 9. The valve of claim 1, wherein the piston is positioned away from a flow path between the mandrel bore and the port when the piston is in the second position. 10. The valve of claim 1, further comprising a biasing member configured to bias the piston into the first position. 11. The valve of claim 1, wherein the pressurized fluid at the first pressure forces the latch across the first tapered surface to move the piston to the second position, and wherein the latch engages the second tapered surface and prevents movement of the piston to the first position when the pressurized fluid is at a third pressure that is less than the first pressure but greater than the second pressure. 12. The valve of claim 11, wherein a biasing member automatically forces the latch across the second tapered surface to move the piston to the first position when the pressurized fluid is at the second pressure. 13. A method for injecting fluid into a wellbore, comprising: lowering a valve into the wellbore, the valve comprising: a tubular mandrel having a bore formed therethrough and a port formed through a wall thereof;a piston axially moveable relative to the mandrel between a first position where the piston substantially seals the bore from the port and a second position where the bore is in fluid communication with the port; anda latch disposed between the piston and the mandrel, the latch operable to resist movement of the piston relative to the mandrel by engaging a first tapered surface when moved from the first position to the second position and by engaging a second tapered surface when moved from the second position to the first position, wherein the first and second tapered surfaces are disposed on one of the mandrel and the piston, wherein the first tapered surface has an angle greater than an angle of the second tapered surface;supplying pressurized fluid through the bore of the tubular mandrel at a first pressure to move the piston from the first position to the second position, wherein the piston automatically returns to the first position when the pressurized fluid is at a second pressure that is less than the first pressure; andinjecting fluid into an annulus of the wellbore surrounding the valve. 14. The method of claim 13, further comprising actuating the piston from the first position to the second position using fluid pressure, thereby opening fluid communication between the bore and the port to inject fluid into the annulus. 15. The method of claim 14, further comprising compressing the latch to move the piston from the first position to the second position. 16. The method of claim 15, further comprising biasing the piston into the first position, thereby closing fluid communication between the bore and the port to stop injection of fluid into the annulus via the port. 17. The method of claim 16, further comprising compressing the latch to move the piston from the second position to the first position. 18. The method of claim 13, further comprising applying the pressurized fluid to the piston at a third pressure that is less than the first pressure but greater than the second pressure while preventing the piston from moving to the first position. 19. The method of claim 13, further comprising forcing the latch across the first tapered surface using the pressurized fluid at the first pressure to move the piston to the second position, moving the latch into engagement with the second tapered surface, and preventing movement of the piston to the first position when the pressurized fluid is at a third pressure that is less than the first pressure but greater than the second pressure. 20. The method of claim 19, further comprising automatically forcing the latch across the second tapered surface using a biasing member to move the piston to the first position when the pressurized fluid is at the second pressure. 21. A method for injecting fluid into a wellbore, comprising: lowering a valve into the wellbore, wherein the valve includes a piston movable from a first position to a second position using pressurized fluid to open fluid communication between a bore of the valve and an annulus of the wellbore surrounding the valve;applying pressurized fluid to the piston;resisting movement of the piston from the first position to the second position using a latch configured to secure the piston in the first position by engaging a first tapered surface;actuating the latch using a force at a first threshold to move the piston from the first position to the second position, wherein the piston automatically returns to the first position using a force at a second threshold that is less than the first threshold;injecting pressurized fluid from the bore of the valve into the annulus of the wellbore; andresisting movement of the piston from the second position to the first position using the latch by engaging a second tapered surface having an angle less than an angle of the first tapered surface, wherein the first and second tapered surfaces are disposed on an inner surface of the valve. 22. The method of claim 21, wherein actuating the latch comprises applying a force to the latch to move it past the first tapered surface to move the piston to the second position. 23. The method of claim 22, further comprising moving the latch past the second tapered surface to move the piston to the first position. 24. The method of claim 23, further comprising biasing the piston into the first position to close fluid communication between the bore of the valve and the annulus of the wellbore. 25. The method of claim 21, further comprising applying a force at a third threshold to the piston to prevent movement of the piston from the second position to the first position, wherein the third threshold is less than the first threshold but greater than the second threshold. 26. The method of claim 21, further comprising forcing the latch across the first tapered surface using the force at the first threshold to move the piston to the second position, moving the latch into engagement with the second tapered surface, and preventing movement of the piston to the first position using a force at a third threshold that is less than the first threshold but greater than the second threshold. 27. The method of claim 26, further comprising automatically forcing the latch across the second tapered surface using a biasing member to apply the force at the second threshold to move the piston to the first position.