In the global push for energy transition and safety, retrofitting aging nuclear power plants is a critical priority. For these upgrades, Nuclear Electric Actuators are essential, serving as the key drivers for critical shut-off valves. Retrofitting within confined original installation spaces to achieve higher temperature resistance, faster response, and more precise control is a significant challenge, particularly in the European market. The selection of high-performance Nuclear Electric Actuators is therefore paramount.
A European nuclear power plant faced such difficulties, requiring retrofit Nuclear Electric Actuators for electric shut-off valves with specifications including 1-second quick opening, 150℃ high-temperature resistance, and full compatibility with the existing control system. Multiple local suppliers had struggled to meet the combined demand for a compact size and high performance in these specialized Nuclear Electric Actuators, causing significant project delays.
Leveraging deep expertise in custom actuator design, the GRAT R&D team focused on developing superior Nuclear Electric Actuators, breaking down the technical challenges into four key areas for targeted development:
1. Delivering High Torque and Speed in a Compact Design for Nuclear Electric Actuators
The client required the Nuclear Electric Actuator to open the valve within one second in a tight space while maintaining a torque output of at least 15N・m. The team re-engineered the gearbox and drivetrain specifically for these compact Nuclear Electric Actuators, removing non-essential parts. The final product was 30% smaller than conventional actuators of the same class, successfully achieving full 0–90° valve opening within one second, with torque consistently above 20N・m. This breakthrough demonstrates that both compact and high-performance Nuclear Electric Actuators can indeed coexist.
2. From Class B to H: Nuclear Electric Actuators Built for Extreme Temperatures
This nuclear project required the electric actuators to pass two core temperature tests: 1500 open-close cycles at 60℃, and 10 hours of continuous operation at 150℃. The initial Class B temperature-rated motor showed insulation degradation at 120℃, unsuitable for reliable Nuclear Electric Actuators in high-temp environments. In response, the team upgraded to Class H high-temperature insulation materials (180°C capability) for all motor windings and electrical components within the Nuclear Electric Actuator. The final units passed both tests without any loss of control accuracy, setting a new standard for high-temperature Nuclear Electric Actuators.
3. Custom Multi-Turn Limit System in Nuclear Electric Actuators Eliminates Travel Error Risk
The client’s proposed thermal management approach risked 45–60° of positioning error, which was unacceptable for nuclear “zero-deviation” standards. For these precision Nuclear Electric Actuators, the team dedicated two weeks to developing a customized limit system. Through multiple technical meetings, the travel error was controlled within only ±1 degree, ensuring the new Nuclear Electric Actuators delivered both structural compactness and exceptional control accuracy.
4. Dedicated Worm Gear Design Ensures Long-Term Life of Nuclear Electric Actuators
Nuclear equipment demands long-term reliability from every component, especially the Nuclear Electric Actuators. The team developed a custom multi-turn worm gear set for these actuators using a special wear-resistant alloy and carburizing and quenching processes, paired with a high-temperature-stable lubricant. Testing showed a 60% reduction in wear rate at 150℃ compared to standard products, ensuring the long-term precision and reliability of the Nuclear Electric Actuators for over 100,000 operation cycles.
The delivered custom Nuclear Electric Actuators were seamlessly integrated into the client’s constrained space and existing control system, meeting all the stringent nuclear standards. This project not only demonstrated GRAT’s capability to deliver advanced Nuclear Electric Actuators for complex challenges but also established a replicable technical blueprint for the nuclear power renovation projects worldwide. GRAT’s customized Nuclear Electric Actuators provide a proven and reliable solution for enhancing the safety and efficiency of nuclear power equipment globally.
