The boiler capacity can be expressed by the rated evaporation or the maximum continuous evaporation.
The maximum continuous evaporation is the maximum continuous production of steam per unit time at the specified outlet pressure and temperature.
The rated evaporation is the amount of steam produced continuously per unit time at the specified outlet pressure, temperature and efficiency.
MCR is the English "Maxium Continuous rating" abbreviation, meaning "boiler maximum continuous evaporation."
