Endurance testing is performed to learn and understand the effects of repetitive cycling and cycle speeds on valve tightness, operating torque, and to monitor the wear behavior of parts. Actuators are tested separately and with valves to demonstrate the total package performance. The number of cycles in an endurance test can exceed 5 million. These tests are regularly performed at all Metso valve testing facilities under various process and environmental conditions to ensure that our valves and actuators are up to the task they have been designed and designated for.
Pressure testing is equally important. One aspect of pressure testing is to ensure that pressure-containing products are safe and more than capable of withstanding their defined ratings. In addition, tightness tests are done to verify the valve sealing performance under different pressures, temperatures, and process media.
Actuator testing is a crucial part of ensuring the performance of the entire valve assembly. Metso valves are designed to be used in most, if not all, environments found on this planet. That means the actuator operating the valve also needs to endure and work flawlessly in these potentially harsh conditions. Metso actuators are used in the hottest locations on earth, as well the coldest arctic conditions, where temperatures reach below -50 degrees Celsius. They too must be rigorously tested to ensure that they provide many millions of issue-free cycles in these extreme conditions. The performance verification of valve actuators includes endurance testing, speed testing, control accuracy, output torque, environment testing, as well as ingress protection and vibration. Endurance tests are conducted using specialized test benches with variable resistance, while output torques are measured with high-precision torque transducers to ensure that they consistently produce the expected output.
In the third and final post, we will talk about environmental testing, as well as the metallographic and tribology testing we carry out on all of the materials and coating we use in our valves.