Annulus Zonal isolation Packer
Saltel XPandable Steel AZIP (Annular Zonal Isolation Packer) uses proprietary expandable stainless steel technology and a patented thin layer of bonded elastomer to achieve zonal isolation.
The elastomer is used together with expandable dynamic seals for temperatures above 250 degF.
AZIP Packer activation procedure
The packer is made up to a casing string that you run into the open or cased hole. Once in position, you apply pressure by pumping from the surface to expand the packer. You can seal the lower end of the casing with a plug and then pressurize the full string above. Alternatively, you can isolate the expansion port, using a cup tool or polished bore receptacle with an inner-string.
While pumping, you will transmit the pressure through the expansion port to the packer’s integral stainless steel sleeve. The sleeve will expand into the annulus between the casing and borehole or outer casing string. It will conform at the same time to the real shape of the wellbore or casing and will isolate the annulus below the packer from the annulus above. Note that the sleeve expansion will also centralize the casing string.
Different models of the AZIP Packer are available to optimize for a range of applications.
AZIP Packer setting process
AZIP Packer applications
0-0 Version
The expansion port is located in the middle of the packer and features a valve system that is integrated within the casing thickness and serves as a safety feature. If the packer is expanded in front of a severe washout, the valve closes, preventing fluid loss.
1-0 and 0-1 versions
These packers feature an expansion and pressure compensation valve at the top (1-0) or bottom (0-1) end that permanently closes the expansion port and establishes casing integrity once the packer is set and a predetermined pressure is reached. This activation pressure can be modified by replacing an easily accessible shear pin. The valve also serves as a safety feature in the event of washouts. Closing the expansion port immediately establishes fluid communication and pressure balance between the annulus at the valve end of the packer and the space inside the expanded steel sleeve. Balancing these pressures enables the packer to withstand higher annulus pressures at that end, providing high sealing capacity and excellent resistance to thermal cycling. The version of packer selected depends on whether high pressure is expected above or below the packer.
