In a boiler, which material is utilized to provide insulation and withstand high temperatures?

The material used in a boiler to provide insulation and withstand high temperatures is refractory. Refractory materials are specifically designed to withstand extreme heat and are able to maintain their structural integrity in high-temperature environments. They are used to line the interior of boilers, furnaces, and other high-temperature equipment due to their ability to resist thermal shock and chemical attack from the combustion process.

Refractory materials not only serve as insulation to minimize heat loss and improve efficiency, but they also protect the boiler's structural components from the damaging effects of high temperatures. Their composition typically includes ceramics and minerals that can endure the harsh conditions found in a boiler, such as constant fire exposure and fluctuating temperatures.

In contrast, while fiberglass is a common insulation material, it is not suitable for the extremely high temperatures found in boilers. Concrete, while sturdy and commonly used in construction, does not provide the necessary temperature resistance required in boiler applications. Metals, on the other hand, can conduct heat and are usually part of the boiler’s structure rather than for insulation purposes. Thus, refractory is the ideal choice for providing high-temperature insulation in boiler systems.