Pipeline isolation Plugs

Supergrip (UK) Ltd have extensive experience in the design and supply of pipeline isolation plugs.

Supergrip provide the complete isolation service which incorporates the following activities:

• pre-isolation site survey of pipeline
• project specific design of the isolation plug and installation tooling
• project management and operating procedures
• supply of all isolation and pigging equipment
• offshore technicians to perform the pipeline isolation process.
• issue of isolation certificate
• project close out report

Typically the isolation tool, particularly the pigging arrangement, will be of a project specific nature as it will cater for pipeline geometry as well as the pressure holding requirement. (downstream / upstream or both).

However the principle of the Isolation Plug itself remains the same for all modules in that the following system is always provided:

• double block and bleed system for pressure verification and operational monitoring.
• self energising seals and collet assembly.
• combined spring and hydraulic release system.
• pipeline pressure over ride system or hydraulic system dump facility which remove hydraulic pressure and releases the plug.

Prior to offshore installation Supergrip perform a thorough Factory Acceptance Test (FAT) of the equipment on a simulated test rig. The test is performed in accordance with an approved Test Procedure.

This is critical to demonstrate the suitability of the equipment prior to offshore operations commencing to avoid any unnecessary delays. The test rig will incorporate a sample of all critical features (eg: a sample bend, large branch connections etc) to confirm the capability of the plug to be pigged through the project pipeline into the isolation position.

Supergrip supply both tethered and tetherless Isolation Plugs with the latter incorporating a micro hydraulic control pod mounted onto one of the pig modules and through wall communication being provided by Extremely Low Frequency (ELF) radio control.

Specification:
• pipe diameters: 3”NS to 36”NS (tethered) 12”NS to 36”NS (tetherless)
• pressure rating: up to 200 bar.g
• maximum depth rating: D3,000m

Features:
• hydraulic failsafe activation / hydraulic deactivation
• double block and bleed failsafe sealing arrangement
• high integrity elastomeric seals and collet grip assembly
* pressure verification / monitoring and downstream pressure monitoring capability