Passive J-Tube Seals are a a low-cost alternative to an ROV activated J-Tube seal, and are generally used in J-Tube seals below 16”ns.
The Passive Seal is connected directly to the riser prior to over-boarding and engaged into the bellmouth via the riser pull-in operation. The unit is clamped to the riser, allowing the Passive Seal to be pulled in to the bellmouth before allowing the riser to slide through the seal at a given force.
The passive seal is preset topside following installation on to the riser using settings defined during factory acceptance testing of the product. Supergrip UK provide each passive seal with separate internal and external seals. The internal seals allow the connection to the riser to be pressure tested following installation. The external seals can then be preset to accommodate the J-Tube tolerances only, meaning that much lower pull-in forces can be achieved compared to alternative products on the market.
Passive J-Tube Seals can be proved in a continuous or split construction to assist with topside installation on to the riser.
Specification:
• Riser sizes: 4”ns – 24”ns
• Bellmouth sizes: 6”ns – 48”ns
• Sealing pressure > 20 bar.g
• Design life: >50 years
Features:
• Pre-deployment pressure testing capability onboard vessel to confirm successful seal against riser / umbilicals
• Split design ensures assembly can be installed after pull-in head assembly