Tree Saver is a tool that is designed to isolate wellhead from being exposed to the high pressure during frac/injection job execution. This is achieved by using a smaller ID circular pipe that has sealing mandrels attached to the outside of this pipe. The tool is rigged up on the wellhead, from the top valve on the x-mass tree (such as the swab valve) through flange connection. When isolation is required, this circular pipe is lowered in the tubing all the way from top wellhead valve to inside the tubing, by-passing all x-mass tree valves, tubing hanger and any crossovers that maybe installed in the tubing. The seals on the outside of this tree saver tubing provides seal within the annulus of well tubing and Tree Saver tubing, which are often pressure rated at 15K psi or more.
The frac pumping lines (or treating iron as they are called) are connected to the top of this smaller ID pipe on the tree saver and fluid is pumped through the treating into this tree saver finally into the high pressure rated well tubulars. The low pressure rated X-mass tree is completely bypassed, not being exposed to high pressure. Following is a schematic of Tree Saver Tool:
Such a simple equipment saves the cost & requirement of installing frac tree on all wells that are planned for fracturing treatment, ultimately economizing the frac project.
This is the end of this MiLog. Tree Savers like everything else has pros & cons, which will be discussed in next MiLog.
