Festo has developed in cooperation with Shell Global Solutions (SGSI) an electric servo actuator for anti-surge control valves (ASCV). The device is also equipped with a unique ‘mechanical fail safe’ (patent pending) mechanism. The actuator has clear advantages compared to the traditional pneumatic solutions, e.g. it enables a more precise control and requires less maintenance during the life cycle of plants due to a less complex design.
ASCVs are used to protect against compressor surge, which can cause catastrophic damage to turbine compressors. An effective ASCV must operate rapidly and precisely – two aspects that represent a major challenge for the current generation of ASCVs, which are usually actuated pneumatically. With the clear target to develop the next generation of ASCV, the Subject Matter Expert (SME) for automated valves, Willem van Rijs (initiator and leader of the Servo Actuator Project between Shell Global Solutions International BV (SGSI) and Festo) undertook research to identify innovative new technologies capable to meet the demanding requirements of the application.
The idea came up to apply technologies from the fields of robotics and mechatronics. Although essentially promising, the development in these technologies to date had not matured into generally available components for immediate application in the heavy process industry, in particular oil & gas. With this in mind, SGSI motivated Festo as a partner to start an intensive cooperation in development. The result is the achieved breakthrough at present. This effort resulted in an innovative actuator using an electric servo motor, which is a totally new technology for these kind of applications with clear advantages compared to the traditionally used pneumatic solutions.
This game changer has a modular construction and is built from a minimum number of components. One big advantage is the much faster action cycle compared to conventional systems. A major contribution to the short cycle time is the elimination of the dead band. The electric servo actuator moves much sooner and faster compared to pneumatic actuators and based on that, the compressor surge prevention measure is executed in a shorter time period. This results in an improved utilization of equipment by operating points nearer to the limits, less compressor drops and a reduced risk for compressor damages.
Besides the higher precision in control the electric actuator has also a lower weight compared to pneumatic solutions.
Additionally, this new technology is considerably less demanding with regards to installation as well as maintenance and offers extensive possibilities for diagnostics. This reduces costs and is an important aspect that contributes to enhanced plant safety and availability, in particular in the heavy process industry.
Moreover, the associated diagnostic data forms a basis for predictive maintenance. When applied in combination with Asset Management Systems (Industrial Internet of Things (IIoT), a Festo field of development), smart diagnostics will lead to improved control of the Total Cost of Ownership (TCO). This is the first step into digitalization of ASCVs. Performance data of ASCVs can be compared globally, resulting in benchmarks of compressor installations and the ability to improve plant yields.
Festo is also closely collaborating with CCC (Compressor Controls Corporation) to further develop and integrate the controller and actuator for optimum surge protection and process efficiency. CCC is the market leader in Turbomachinery Controls and related optimization services for the upstream, midstream and downstream oil and gas and petrochemical industries. The integration of the Festo Servo-Actuator with CCC control systems increases the operating area while maintaining stable and effective surge protection.
This new Festo product is available to every OEM or user in combination with any brand of ASCV, and/or (in future) with other applications, such as Emergency Shut Down On/Off valves.
Festo AG is a global player and an independent family-owned company with headquarters in Esslingen am Neckar, Germany. The company supplies pneumatic and electrical automation technology to 300,000 customers of factory and process automation in over 40 industries. The products and services are available in 176 countries. With about 20,100 employees in over 250 branch offices in 61 countries worldwide, Festo achieved a turnover of around €3.1 billion in 2017. Each year around 8 % of this turnover is invested in research and development.
In this learning company, 1.5 % of turnover is invested in basic and further training. Yet training services are not only provided for Festo's own staff – Festo Didactic SE also supplies basic and further training programmes in the field of automation technology for customers, students and trainees.