Ongoing process steam leakage in power plant control valves due to erosion from wet steam must be addressed to maximise uptime at a critical time for the industry, says a power industry expert.
Continually rising gas prices caused by geopolitical events have put pressure on facilities to ensure continued, uninterrupted performance, and further heightened the impact of inefficient processes and unplanned downtime. However, power plants with inadequate drain arrangements, incorrect bypass operation, improper valve calibration or inadequate pre-warming processes continue to be impacted by wet steam erosion, hampering productivity.
Specifically, these issues can lead to erosion of trim components on steam valves used in critical service applications caused by flashing condensate, otherwise known as wet steam. According to Mike Semens-Flanagan, Global Engineering Director at IMI Critical Engineering, this potentially chronic problem must be addressed if facilities are to remain efficient and cost-effective at a time when process costs are rising.
One such way to minimise wet steam erosion is to ensure that any condensate has minimal contact with sealing surfaces. IMI Critical Engineering, for example, has developed EroSolve Wet Steam, which upgrades the valve’s plug, stem assembly, cage, and seat ring. The solution has specially engineered sealing surfaces that optimise droplet impingement angles to reduce their impact. Its use of special, erosion-resistant hard-facing materials also enhances trim life in a solution that can be easily implemented in any make of control valves.
EroSolve Wet Steam’s impact can be seen at a Korean Combined Cycle Power Plant where operators experienced excessive trim erosion due to high condensate levels caused by frequent plant start-ups and shutdowns. The impact on the trim and subsequent issues with adjacent piping led to expensive unplanned facility shutdowns that were solved following EroSolve Wet Steam installation.