Session: DA-10-01 Design and Analysis of Bolted Joints

Paper Number: 122793

122793 - Metalic Seal Ring Reusability 

Metal-to-metal seals, exemplified by well-established designs like Techlock and Bluelock, have emerged as preferred choices for both self-energized and pressure-energized sealing solutions. These seal designs find extensive application in clamp-hub-type connections and compact flanges. By employing high-strength materials with elevated specified minimum yield strength, the reusability of these seals is substantially enhanced, consequently extending their operational lifespan from a sealability perspective.

Unlike the classical ratcheting model of Bree, which is based on the combination of primary membrane stress and alternating secondary bending stress in the same direction, ratcheting in this context can occur solely due to secondary stresses during the make-up (assembly) and break-out (disassembly) phase. This study centers on simulating the make-up and break-out cycles of these seals. The primary objective revolves around evaluating how key design parameters—specifically seal sizing and yield strengths—impact the distribution of plastic strain and the overall potential for reusability of the seal rings. In pursuit of this goal, a comprehensive assessment utilizes an elastic-plastic stress analysis method, as detailed in section 5.5.7 of ASME VIII Div. 2.

The study's findings unequivocally affirm that employing a minimum specified yield strength of 75 Ksi significantly enhances the reusability and operational lifespan of these seal types. This conclusion is in harmony with empirical insights gathered from various industries and is consistent with existing acceptance criteria, notably the stand-off value, which provides a quantitative measure of reusability potential.

Presenting Author: Reza Payvar Freudenberg Oil & Gas Technologies

Presenting Author Biography: Reza Payvar
Licensed Professional Engineer (P.Eng.)

With a distinguished career spanning over 15 years in the Oil, Gas, and Petrochemical industries, I am a highly regarded authority in the field of Integrity Evaluation and Design of Pressure Equipment. As a Licensed Professional Engineer (P.Eng.), I bring a wealth of expertise and experience to the table.

My specialized knowledge extends to a broad spectrum of Pressure Equipment, including Piping, Pipelines, High-Integrity Connectors, Pressure Vessels, and Heat Exchangers. This breadth of experience has been honed through extensive work in various industry segments, including roles at Azar-Ab Industries Co., SAPCO (Supplying Automotive Parts Co.), and Freudenberg Oil and Gas Technologies.

I hold a Bachelor's and Master's degree in Mechanical Engineering, underpinning a deep understanding of the core principles that drive the Oil and Gas industry. My proficiency in Finite Element Analysis, Pipe Stress Analysis, Fatigue Life Assessment, Fitness-For-Service evaluations, and Fracture Mechanics is widely recognized and has been instrumental in optimizing the reliability and safety of critical assets in the industry.

As an esteemed author, I am committed to advancing the state of the art in the field, and my contributions to the ASME community reflect a dedication to excellence and innovation. My technical paper promises to be a valuable addition to the ASME library, drawing from a career enriched by diverse experiences and a relentless pursuit of engineering excellence.

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