Where does scale most commonly form in a boiler?

Scale most commonly forms in the steam generating sections of a boiler due to the high temperatures and pressures found in these areas. As water is heated, dissolved minerals and impurities tend to precipitate out of the solution, especially when water is evaporated to produce steam. This precipitation occurs most significantly where the water reaches its boiling point.

The steam generating sections often experience the most intense heating, which drives the formation of scale more than in cooler areas or external surfaces, where heat is less concentrated. Scale buildup can severely impact the efficiency and safety of boiler operation by insulating heating surfaces, which can lead to overheating and potential damage. Regular monitoring and treatment of the feedwater are essential to minimize scale formation in these critical areas.