Release tool for downhole operations

1. An apparatus for connecting and releasing a downhole tool located within a wellbore comprising:

a housing having an axial bore;

an electronics assembly configured to communicate with the surface of the wellbore;

an activation mechanism configured to receive an electrical current from the electronics assembly;

a valve assembly in operative communication with the activation mechanism and having a first piston configured to open a port in the housing to wellbore fluid;

a second piston slidably engaged with the housing and held in an initial downward state by a spring;

plural retainer dogs each having an engagement recess disposed on an inner radial surface thereon configured for clamping a neck of a tool when the retainer dogs are in a first position; and

wherein said second piston further comprises a cavity configured to retain said retainer dogs in the first position and to allow the retainer dogs to move radially outward to a second position when the second piston is acted upon by the wellbore fluid.

2. The apparatus of claim 1 wherein the housing is comprised of an upper section and a lower section connected by a main sub.

3. The apparatus of claim 2 , wherein the activation mechanism is located within the main sub.

4. The apparatus of claim 2 , wherein the valve assembly is located within the main sub.

5. The apparatus of claim 1 , wherein the valve assembly further comprises a burst disk.

6. The apparatus of claim 1 , wherein valve assembly is further configured to activate a switch to communicate a state of the valve to the electronics assembly.

7. An apparatus for connecting and releasing a downhole tool located within a wellbore comprising: a housing having an axial bore;

a burst disk located within the housing and configured to open a passageway to wellbore fluid upon breakage at a predetermined pressure;

a piston located within the housing and held in an initial downward state by a spring;

plural retainer dogs having an engagement recess disposed on an inner radial surface thereon configured for clamping a neck of a tool when the retainer dogs are in a first position; and

wherein said piston further comprises a cavity configured to retain said retainer dogs in the first position and to allow the retainer dogs to move radially outward to a second position when the piston is acted upon by wellbore fluid.

8. The apparatus of claim 7 , wherein the housing is comprised of an upper section and a lower section connected by a main sub.

9. The apparatus of claim 8 , wherein the burst disk is disposed within the main sub.

10. A wireline release tool and measurement system, the system comprising:

a wireline for lowering a tool string into a wellbore;

a housing attached to the wireline and comprising an upper section, a lower section, and an axial bore;

a main sub connecting the upper section and lower section of the housing;

an electronics assembly configured to communicate with the surface of the wellbore via the wireline;

a release assembly comprising plural retainer dogs each having an engagement recess disposed on an inner radial surface thereon configured to clamp a neck of a tool when the retainer dogs are in a first position and to release the neck when the dogs move radially outward to a second position, such that the housing and the tool are separated from each other and the housing may be pulled out of the wellbore using the wireline; and

a measurement sensor disposed within the main sub and-configured to measure a parameter and communicate a measured value to the electronics assembly.

11. The system of claim 10 , wherein the release assembly further comprises a valve assembly located in the main sub configured to open a passageway to wellbore fluid.

12. The system of claim 10 , wherein the release assembly further comprises a piston having a cavity configured to retain said plural retainer dogs in a clamped state until said piston is acted upon by wellbore fluid.

13. The system of claim 10 , wherein the measurement sensor is a temperature sensor for measuring wellbore temperature.

14. The system of claim 10 , wherein the measurement sensor is a pressure transducer for measuring wellbore pressure.

15. The system of claim 10 , wherein the measurement sensor is a tension transducer for measuring tension of the tool string.

16. The system of claim 15 , wherein the tension measurement further comprises a pressure compensation chamber to compensate for the pressure driven compression of the tension transducer.

17. The system of claim 16 , wherein the pressure compensation chamber is further comprised of more than one sealing surface with varying cross-sectional area to pressure balance the transducer relative to the wellbore exterior pressure.

18. The system of claim 16 , wherein the pressure compensation chamber is disposed within a second sub separate from the main sub.

19. The system of claim 10 , wherein the electronics assembly comprises:

a housing;

a processor that is electrically connected to both the release assembly and the at least one measurement sensor; and

wherein the processor is configured to receive a signal from the surface of the wellbore to initiate the release assembly and transmit a measured parameter measured by the measurement sensor to the wellbore surface via the wireline.