How are the capacities offield erected boilers generally categorized?

Field erected boilers, which are typically constructed on-site at industrial facilities, are categorized based on their steam generation capacity. These capacities are important for determining the type of boiler design, operational parameters, and suitability for specific applications.

The correct choice indicates that these boilers are often categorized as having capacities over 50,000 kg/h. This classification reflects the significant demand these installations can accommodate, as field erected boilers are often designed for larger applications, such as in power plants or large manufacturing facilities. The higher capacity allows for increased efficiency and the ability to meet the high thermal requirements of various industrial processes.

Other ranges mentioned, such as under 20,000 kg/h or fixed at 25,000 kg/h, typically refer to smaller, packaged boilers readily available from manufacturers and installed with minimal site preparation. The range between 30,000 kg/h and 60,000 kg/h suggests a midpoint but does not capture the larger designs that are characteristic of field erected installations. Therefore, categorizing field erected boilers based on their capacity over 50,000 kg/h is consistent with industry standards and practices for larger, custom-designed systems.