Annulus Safety Valve (ASV)
The ASV is mainly installed in gas lift wells, and preferably at a shallow depht to minimize the amount volume of gas above the ASV.
It have also been used at TLP oil rigs.
Annulus Safety Valve (ASV) is a gas flow barrier in annulus.
Annulus Safety Valve consists of a packer with an opening (Micro annulus). The valve is surface operated, It is a “fail-safe close” device for annular flow.
For more detailed information and history of the ASV click here: