CT Logo

John Crane, a global leader in flow control technologies and a business of Smiths Group plc, has developed an industry-first validated methodology that significantly improves the accuracy of drivetrain analysis in critical rotating equipment. The breakthrough approach reduces predictive variance, helping operators reduce failure risk, improve reliability and gain greater confidence in system performance before start-up.

As rotating equipment systems become more complex, particularly those operating across variable speeds, accurately predicting how they will behave in real operating conditions has become increasingly challenging. Traditional modelling methods rely on assumptions that do not fully reflect real-world behaviour, creating a gap between expected and actual performance that can lead to vibration issues, reduced asset life or unplanned downtime.

Closing the gap between prediction and reality

John Crane’s methodology addresses this challenge by treating drivetrain behaviour as dynamic rather than fixed, capturing how performance changes under different operating conditions. This enables a more representative and reliable understanding of system behaviour.

A new way to model drivetrain behaviour

At the core of the development is a new methodology for analysing torsional disc coupling stiffness in rotating equipment drivetrains.

Traditionally, drivetrain analysis has treated torsional stiffness as a fixed value. John Crane’s methodology instead recognises that stiffness changes under different operating conditions and levels of torque.

By combining advanced modelling, static and dynamic testing, and real-world operational data, the methodology creates a far more accurate representation of how drivetrains behave in operation.

This allows engineers to predict critical frequencies and system behaviour with significantly greater precision, reducing uncertainty and helping avoid issues that might otherwise only emerge during commissioning or operation.

Developed over three years, the approach has been rigorously validated across analytical modelling, static and dynamic testing, and real-world customer applications. This level of correlation between predicted and measured performance is a significant benefit to drivetrain analysis.

The methodology addresses a long-standing challenge within drivetrain analysis that has historically limited the accuracy of predicting real-world operating behaviour.

While aspects of torsional stiffness behaviour have been discussed previously in academic research, John Crane's methodology is distinguished by its validation through analytical modelling, physical testing and successful implementation in real-world applications.

Clear impact for customers

For operators in industries such as oil and gas, LNG and power generation, where rotating equipment is critical to operations, the benefits are immediate and measurable:

•       Reduced risk of unexpected failure

•       Greater confidence during commissioning and start-up

•       Improved reliability and uptime

•       More informed decision-making in system design and operation

In environments where downtime can cost millions per day, improving predictive accuracy can have a direct impact on operational performance, project delivery and costs.

Proven in real-world applications

The methodology is already in use and has been successfully implemented in live customer applications and validated in collaboration with leading OEMs and operators.

By combining advanced modelling techniques with extensive testing and real-world validation, the approach delivers a level of confidence that goes beyond traditional methods.

A practical step forward for the industry

Steve Pennington, Global Engineering Coupling Manager at John Crane, said: “This is a significant advancement in how drivetrain behaviour is understood and predicted. For years, the industry has relied on simplified assumptions that do not fully reflect real operating conditions. By validating this methodology through testing and live applications, we are giving customers a far more accurate and reliable understanding of system behaviour.”

Supporting the next generation of systems

As industrial systems evolve, particularly with the increased adoption of variable speed technologies, the need for more accurate and representative modelling will continue to grow.

This development provides a practical and proven way to improve reliability, reduce uncertainty and support more resilient operations across critical applications.