- Prevent possible formation breakdown
- Avoid loss of cement slurry
- Prevent gas migration
- High-pressure/high-temperature environments
- High load capacity requirements
- Low equivalent circulating density requirements
The ZXP-N is a compression-set liner top packer that uses a modified ZX packing element design to ensure an effective liner top seal. The expanding metal seal element is molded with a bonded nitrile (HNBR) elastomer for a high-pressure rating and for high-circulation rates at moderate temperatures.
The annealed steel and elastomer ZX element is actuated by applying set-down weight to the tieback extension through the setting dogs on the liner running tool. This force drives the ZX seal up a ramp, causing it to expand and conform to the casing’s inside diameter (ID). The element’s external ribs seal off any extrusion gap, trapping the setting force and preventing flow of the elastomer. A body-lock ring system incorporated in the ZX seal holds a permanent set in the seal after it is actuated.
The ZXP-N liner top packer is typically run as an integral component of the primary liner hookup and is compression-set using a packer-setting dog sub or a hydraulic pusher tool.
Expanding metal seal element with a bonded nitrile (HNBR) elastomeric cover ensures seal integrity at moderate temperatures
Bonded ZX seal prevents swab-off and allows for higher circulation rates