Shell explains the benefits of working with OCAS
“We set up a multi-year programme to better describe the mechanisms of metal-to-metal sealing, focusing on the surface conditions in particular. As highly specialised competences and academic knowledge were needed in different fields of expertise, we established a consortium involving OCAS and the partner universities of Lulea and Twente.
The implemented methodology required a co-developed experimental set-up “Shell sealing and mock-up rig” for which OCAS designed and realised the hard and software. This assembly and its design aim at simulating conditions during a full-scale ISO 13679:2011 CAL IV test programme. Unlike the CAL test which qualifies leak tightness, this test rig is used to deliberately find the onset and the location of leakage.
Results from this test rig were used to validate the numerical models and to differentiate the performance of different samples. This allowed a better understanding of the sealing mechanisms of metal-to-metal seals.
OCAS simultaneously developed a numerical model to demonstrate the effects of out-of-roundness deviations of the geometry on the connection sealing performance.
The fruitful cooperation of all four partners resulted in a joint scientific publication. Going forward, research data can now be used to optimise the design of metal-to-metal seals”
Roel FH Roijmans, Wells Technology Engineer, Shell Projects & Technology
Related scientific paper
Ernens D., Pérez-Ràfois F., Van Hoecke D., Roijmans R., van Riet E. Vande Voorde J., Roggeband S. van Haaften W. Vanderschueren M. and Pasaribu H., “On the sealability of metal-to-metal seals with application to premium casing and tubing connections”, Society of Petroleum Engineers SPE/IADC International drilling conference and exhibition, The Hague, 5-7 March 2019.
”This collaboration resulted in the design of an experimental test set-up enabling the investigation of assembly, micro-sliding and sealability for gas or liquid pressures up to 1500 bar and is highly representative for industry.”