Welltec® Light Packer for cement assurance and eliminating SCP
Sustained Casing Pressure (SCP) is typically observed as an excessive level of pressure in a well – it is directly linked to compromised well integrity and poses a number of safety and environmental risks.
The Welltec® Light Packer (WLP) provides life of well integrity, completely eliminating SCP and the need for SCP-related Interventions. This in turn takes pressure off the environment by preventing the release of potentially harmful gases such as methane.
In this case, a high-pressure target formation was causing microannulus challenges and SCP between the B-annulus and production casing. Due to formation geology, cementing the well proved challenging and without enhancement would likely lead to SCP issues.
It was illustrated to the Russian client that by completely eliminating SCP, a number of resources would be freed, which would inevitably have been required to control SCP. By developing a SCP prevention agenda with the client, Welltec delivered an 8.5” light packer (812WLP).
The 812WLP 10k was installed as part of a 7” production casing. A compensation system would allow the packer to hold up to 10,000 psi well pressure from the zone below – a higher pressure than that of the target formation.
The WLP is also able rotatable, allowing the completion string to be turned in order to navigate any difficulties in reaching the target depth, without damage to the packer elements.
The WLP was run to a vertical depth 600 m below the permafrost zone. During the deployment, an onset valve prevented the unintentional setting of the packer during high pressure circulation and cementing, and a sheer-pin valve was used to revert well integrity after the WLP was set.
SCP was completely eliminated from the well, building on the strong track record of the WLP as an effective completion solution for the client.
To date, every well in which the packer has been deployed has experienced zero SCP.
By eliminating SCP, the need for future Intervention is also removed, as well as any associated negative externalities – whether logistical or operational – helping to greatly reduce any impact to the environment.