由于蒸汽热风炉属于特种设备，本身就是制造热源。所以燃煤蒸汽热风炉在制造时对使用的金属材料的要求就格外严格。而挑选耐热、保温材料时所注重的主要性能有下列各项： (l)耐火性。耐热、保温材料的耐火性一般用耐火度和荷重软化温度束表示。耐火度是指材料在高温下抵抗熔化的能力，它是耐热材料最重要的性能之一。材料耐火度的高低取决于其化学组成和杂质的种类及含量。耐热材料的使用温度不允许超过其耐火度，也不能以耐火度作为材料使用温度的上限。和重软化温度是指材料在一定的压力(0.2MPa)下不断加热，发生一定变形量时的温度，它是耐热材料高温机械性能的主要指标。荷重软化温度与材料的化学组成和组织结构有关，材料的荷重软化温度越高，则其使用温度越高。

Because the steam hot stove belongs to the special equipment, it is the heat source in itself. Therefore, the requirements for the metal materials used in the manufacture of the coal-fired steam hot stove are particularly strict. The main properties of heat and insulation materials are as follows:

(L) fire resistance. The fire resistance of heat-resistant and thermal insulation materials is usually expressed by refractoriness and load softening temperature. Refractoriness refers to the ability of materials to resist melting at high temperatures. It is one of the most important properties of heat-resistant materials. The refractoriness of materials depends on their chemical composition and the type and content of impurities. The service temperature of the refractory material shall not exceed its refractoriness, nor shall the refractoriness be used as the upper limit of the service temperature of the material. Resoftening temperature refers to the temperature at which the material is continuously heated under a certain pressure (0.2 MPa) and a certain amount of deformation occurs. It is the main index of high-temperature mechanical properties of heat-resistant materials. The load softening temperature is related to the chemical composition and structure of the material. The higher the load softening temperature is, the higher the service temperature is.

(2)常温及高温耐压强度。常温耐压强度是指材料在常温下所能承受的最大压应力，它主要用来判断成型材料的质量、抗撞击、抗磨损以及抵抗其他机械作用力的能力。高温耐压强度是指材料在一定温度下所能承受的最大压应力

(2) compressive strength at room temperature and high temperature. Compressive strength at room temperature refers to the maximum compressive stress that materials can bear at room temperature. It is mainly used to judge the quality of forming materials, impact resistance, wear resistance and resistance to other mechanical forces. High temperature compressive strength refers to the maximum compressive stress of materials at a certain temperature.

(3)高温体积稳定性（残余收缩或膨胀）。高温体积稳定性是指材料在高温下长期使用中产生的再结晶和进一步烧结，使材料体积发生收缩或膨胀。这种变化是不可逆转的变化。

(3) high temperature volume stability (residual shrinkage or expansion). Volume stability at high temperature refers to the recrystallization and further sintering of materials during long-term use at high temperature, resulting in shrinkage or expansion of material volume. This change is irreversible.

(4)热震稳定性。热震稳定性是指材料承受骤冷骤热的性能，它反映耐热材料抵抗温度变化而不损坏的能力。

(4) thermal shock stability. Thermal shock stability refers to the ability of materials to withstand sudden cooling and sudden heating, which reflects the ability of heat-resistant materials to resist temperature changes without damage.

(5)抗渣性。抗渣性是指耐热材料在高温下抵抗熔渣化学、物理作用的性能。选用耐热材料时应注意熔渣的性质，使之能适应熔渣的特性。

(5) slag resistance. Slag resistance refers to the resistance of heat resistant materials to chemical and physical functions of molten slag at high temperatures. The properties of molten slag should be paid attention to when selecting heat resistant materials, so that they can adapt to the characteristics of molten slag.

(6)容重，容重是材料单位体积的重量，其大小影响到燃煤蒸汽热风炉构架的承载力。同一种材料的容重不同，其导热性能和耐压强度也不同口

(6) Volume weight, which is the weight per unit volume of material, affects the bearing capacity of the frame of coal-fired steam stove. The same material has different bulk density, and its thermal conductivity and compressive strength are also different.

(7)导热性。材料的导热性通常用导热系数来表示，导热系数随材料种类和使用温度而变化。导热性是衡量耐热保温材料特别是保温材料优劣的一个重要性能指标。

(7) thermal conductivity. The thermal conductivity of materials is usually expressed by thermal conductivity, which varies with the type of materials and the temperature of use. Thermal conductivity is an important performance index to measure heat insulation materials, especially insulation materials.