Purpose
To enable the wellbore to be shut in downhole rather than at surface, the benefit of this is to allow for a quicker well build up as it does not have to pressurize the tubing.
Operation
The shut in tool is run in the open position with the inner sleeve pinned so that it will not close prematurely. Once set the in the desired location you can flow the well or perform any other function needed while the tool is open. When readyto shut the tool in, run the appropriate prong with wireline and jar down on the inner sleeve of the shut in tool, shearing two small brass pins and move the inner sleeve down blanking off the ports and effectively shutting in the well bore.
The tool comes with a kobes equalizing plug in the bottom end of the shut in tool so that pressure can be equalized above and below before pulling the assembly. This is done by running another prong which is made to pass through the inner sleeve and break off the kobes plug which will allow the pressure tomigrate up through the tool. The tool then can safely retrieve the shut in tool.
This tool can be easily serviced and pinned again in the field for multiple runs. The kobes plug will need to be replaced after each use.
Precautions
Ensure kobes plug is sheared and well has equalized before unlocking assembly.