Purpose
The G Elements is designed to pack off the wellbore using an expandable rubber element.
The G Element is used in tandem as a straddle pack-off for isolating and containing damaged tubing or as a standalone pack off when conventional plugging equipment is not available.
Description
The BT “G” element assembly can be used for a number of different wireline operations, it can be attached to a second element assembly via a flow tube that threads in the bottom of the upper element assembly and the top of the lower, tubing stops above and below may be use to lock the pack off in place.The “G” element assembly may also be used individually in conjunction with a “G” anchor and any of a number of different types of equalizing assemblies for various applications, the most common being a stand alone pack off for packing off tubing where a conventional plug is not available, or profile nipples are absent.
Operation
The G Element assembly when run in conjunction with a G anchor requires that a stop of some type set to act as a base for the pack off.
It is critical that the element be energized, and the centralizing lugs are deployed before the anchor is engaged. Steel shear pins should be installed in the anchor to ensure that the element assembly is engaged and a proper seal with the tubing wall is made.
When run as a straddle pack off, a conventional fishneck will be run in place of an anchor. Tubing stops should be utilized above and below to hold the pack off in position.
Before retrieving the pack off, ensure that the pressure is equalized above and below the pack off via the preferred equalizing assembly installed prior to installation in the wellbore. Latch and release the anchor. Jar with spangs (or preferred type of jar) until the element assembly disengages the tubing wall and retrieve from well.
* Excessive or heavy jarring may damage the Pack Off. It is recommended that small holes be drilled around circumference of the element to eliminate the chance of hydraulics occurring while setting or unsetting the rubber element. *
