The replacement cycle of expansion joints (compensators) in power plants is affected by a variety of factors, including working environment, media properties, operating conditions and material selection. Here are some guidelines for replacement cycles based on different environments:
Plain rubber expansion joint：
Normally, the replacement cycle of rubber expansion joints is recommended to be around 2-3 years.
If the expansion joint is used to transport chemicals, acidic-alkaline, or corrosive media, the replacement cycle may need to be shorter to avoid early failure due to corrosion.
Condenser rubber expansion joint：
According to the experience of some manufacturers and peer power plants, the replacement cycle of condenser rubber expansion joints can be set to approximately once every 15 years. However, this cycle is longer and usually applies to relatively stable work environments.
Expansion joints in coal-fired power plants：
In coal-fired power plants, the average service life of expansion joints is typically more than 5 years. At lower operating temperatures (
Expansion joints for oil-fired power plants：
If light oil or diesel is used as fuel, the life of the expansion joint is about 3-4 years.
If heavy oil or crude oil is used, the life may be shortened to 1-2 years because the combustion of heavy oil and crude oil generates more impurities and may require more frequent cleaning, thereby accelerating the wear of the expansion joints.
Expansion joints for hydropower plants：
Due to the special environment of hydropower stations, the installation of expansion joints is often difficult to repair or replace, so high safety and reliability are considered when designed. Expansion joints are generally maintenance-free, with the exception of necessary anti-corrosion measures, for the specified service life.
Importantly, although the above provides a generic replacement cycle, the specifics of each power plant may vary. Regular inspections and maintenance are essential to assess the actual condition of the expansion joint. If any abnormalities such as leaks, corrosion, or mechanical damage are found during the inspection, replacement should be performed immediately even if the scheduled replacement cycle is not met to prevent potential safety incidents.
Finally, the specific replacement cycle should be determined in combination with the equipment manufacturer's recommendations, industry standards and the plant's own operating experience.