When an LNG client sought assistance for a challenging subsea project, KLINGER Australia rose to the occasion, transforming the endeavour into a global collaboration. Spearheaded by project engineering manager Nick Evans and supported by technical lead Scott Whelan from KLINGER UK, the team embarked on creating the largest high-pressure class Sentry gasket to date, measuring over 1.1 metres (43.3 inches) in diameter at DN1050 (42”) Class 1500#.

KLINGER Sentry gaskets are essential for high-pressure and hazardous pipeline applications. They are crafted from a variety of core materials to ensure compatibility with different media and temperature ranges. Key features include:

• Capability to perform leak tests on single connections, reducing the need to pressurise entire systems, minimising testing media usage, and avoiding costly downtime.
• Validation of each joint’s integrity at installation, reducing the need for subsequent inspections.
• Compliance with API 6A, ASME B16.20, and ASME B16.5 standards.
• The KLINGER Gasket Insertion Tool (KGIT), designed to work with standard subsea tooling, ensures diver safety during operations.

Specialised Manufacturing Processes

Manufacturing large diameter gaskets requires specialised processes beyond standard methods. For instance, the depth of the holes in this particular gasket exceeded the capabilities of regular drilling, necessitating the use of electrical discharge machining. EDM employs an arc created by electrodes and dielectric liquid, particularly effective on hard metals. Additionally, custom fixtures were designed to secure the ring during EDM and to weld the rings together.

Safe Delivery and Installation

Designing and building these enormous gaskets was just the initial phase. Ensuring their safe delivery to the job site posed another challenge. Due to the labor-intensive nature of producing custom gaskets, they are shipped in pairs to provide a spare in case of any issues. The gaskets must remain flat, level, and stable during transit. Special jigs are used to mount and protect the gaskets’ shape and sealing surfaces during their journey across the sea.

The collaboration between KLINGER Australia and KLINGER UK highlights the innovative spirit and technical prowess required to meet complex project demands in the LNG industry. This project not only set a new benchmark for gasket size but also demonstrated KLINGER’s commitment to safety, efficiency, and global teamwork.

For more information visit www.klinger-international.com

15 July 2024