When an LNG client turned to KLINGER Australia for help with a subsea project, it quickly became a global effort. Project Engineering Manager Nick Evans spearheaded this initiative and joined forces with Technical Lead Scott Whelan of KLINGER UK: at DN1050 (42”) Class 1500#, this gasket would be the largest high pressure class Sentry model to date at over 1.1 meters (43.3 inches) in diameter.
Fact box
KLINGER Sentry Gaskets
» Metallic gaskets used in high pressure and hazardous pipelines
» Available in a variety of core materials, based on media compatibility and temperature range
» Allows leak testing on single connections to avoid pressurizing the whole system, reduce volume of testing media used, and minimize costly downtime
» Validates each joint’s integrity at installation, reducing the need to re-visit the joint
» Meets API 6A, ASME B16.20, and ASME B16.5 standards
» KLINGER Gasket Insertion Tool (KGIT) works with standard subsea tooling and protects divers from injury
Specialized processes
When manufacturing large diameter gaskets, the process often differs from the usual methods for standard sizes. Holes in this gasket would be too deep to use regular drilling, requiring the team to shift to electrical discharge machining (EDM). This process creates an arc using electrodes and dielectric liquid, and is particularly effective on hard metals. Other specialized processes included a custom fixture built to hold the ring in place for EDM, as well as a second fixture built to weld the rings together.
Of course, designing and building these giant gaskets was only the beginning. Next, KLINGER had to safely deliver them to the job site. Because these custom gaskets are so labor intensive, they are shipped in pairs, to ensure that a spare is ready should any problems occur. They must stay flat, level, and still during their journey across the sea. Special jigs are used to mount the gaskets for the trip, protecting their shape and sealing surfaces.
Contacts mentioned in the article:
Scott Whelan, Technical Lead of KLINGER UK
Nick Evans, Project Engineering Manager of KLINGER Australia
Large gasket development
With this project completed successfully, KLINGER has refined the logistics of large gasket development, reducing delivery to a highly competitive time frame.
“From purchase date to installation, we’re at about 20 weeks. We were basically the only people who could do it.”
Scott Whelan, Technical Lead of KLINGER UK
Installation and testing took a total of only 4 hours, with the customer saving an estimated 44 hours of downtime when compared to pressuring the full system using conventional methods. The subsea Pig Launcher Receiver (PLR) was deployed to a depth of 280 meters. With skilled subject matter experts and custom facilities now in place, the project scope will only continue to increase. Current resources support the production of Sentry gaskets up to DN1500/60 in, though the team isn’t ruling out even larger efforts in the future. Nick remarks, “We keep pushing the boundaries with Sentry.”
