ASTM C687-12由美国材料与试验协会 US-ASTM 发布于 2012。
ASTM C687-12 在中国标准分类中归属于: Q25 绝热、吸声、轻质与防火材料。
ASTM C687-12 松填建筑绝热材料隔热性能的测定用标准实施规程的最新版本是哪一版？
最新版本是 ASTM C687-18 。
4. Significance and UseTop Bottom
4.1 The thermal resistance, R, of an insulation is used to describe its thermal performance.
4.2 The thermal resistance of an insulation is related to the density and thickness of the insulation. It is desirable to obtain test data on thermal resistances at thicknesses and densities related to the end uses of the product.
4.3 In normal use, the thickness of these products range from less than 100 mm (4 in.) to greater than 500 mm (20 in.). Installed densities depend upon the product type, the installed thickness, the installation equipment used, the installation techniques, and the geometry of the insulated space.
4.4 Loose-fill insulations provide coverage information using densities selected by manufacturers to represent the product settled densities. Generally, it is necessary to know the product thermal performance at a representative density. Some coverage charts utilize multiple densities to show that greater thickness installations usually result in higher installed densities. The use of multiple densities can be detected from the coverage chart by calculating the density for several different thermal resistance levels. (The density for a given thermal resistance can be calculated from the coverage chart by dividing the minimum mass per unit area by the minimum thickness.) If the calculated densities are significantly different at different thermal resistances, the multiple density strategy has been used.
4.5 When applicable specifications or codes do not specify the nominal thermal resistance level to be used for comparison purposes, a recommended practice is to use the Rsi (metric)8201;=8201;3.3 m2K/W (RIP = 19 [h ft2F/Btu]) label density and thickness for that measurement.
4.6 If the density for test purposes is not available from the coverage chart, a test density shall be established by use of applicable specifications and codes or, if none apply, agreement between the requesting body and the testing organization.
4.7 Generally, thin sections of these materials are not uniform. Thus, the test thickness must be greater than or equal to the product???s representative thickness if the results are to be consistent and typical of use.
Note 1???The representative thickness is specific for each product and is determined by running a series of tests in which the density is held constant but the thickness is increased. The representative thickness is defined here as that thickness above which there is no more than a 28201;% change in the resistivity of the product. The representative thickness is a function of product blown density. In general, as the density decreases, the representative thickness increases. Fortunately, most products are designed to be blown over a small range of de......
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