The hazards of electrostatic precipitators in power generation are well known. High-voltage current, confined spaces and the respiratory risk of fly ash all put workers in potential danger. These issues are compounded by infrequent access and harsh environmental conditions.
This is why selecting a trapped key safety system that provides protection for many years is an important factor in safeguarding power station workers.
Factors to consider when choosing a system include:
• the product’s ability to withstand hot and cold climates
• outdoor use
• the impact of fly ash
This means the type of key (heavy- or light-duty), the material (brass or stainless steel) and the location of the interlocks are crucial to determining long-term usability.
This is only part of the story, though. To perform reliably over many years, interlocking systems need to be maintained and should be serviced as part of a shutdown regime. Simple preventative maintenance steps, such as using graphite powder rather than grease, have a huge impact on longevity.
Regular functionality testing of locks can also prolong a trapped key safety system’s life. This ensures the system is fully operational, saving time and money during a planned or unplanned outage. If locks are only used during an outage and they fail, it can take time to repair or replace them.
Should a failed lock prevent a power station from being brought back online, the financial penalties incurred could be severe. For this reason, it is best practice to regularly check and maintain locks between outages.
With the right maintenance plan, system selection and material choice, a trapped key interlocking system can provide 30-40 years’ service on an electrostatic precipitator, in even the harshest locations.