ASTM C204-18e1 PDF Download

ASTM C204-18e1 is a standard test method that is used to determine the fineness of hydraulic cement. It utilizes the Blaine air-permeability apparatus to measure the specific surface of the cement, which is expressed as the total surface area in square centimeters per gram or square meters per kilogram. The standard provides two test methods: Test Method A, which is the reference method using a manually operated Blaine apparatus, and Test Method B, which allows for the use of automated apparatus that meets the qualification requirements of the standard.

The Blaine air-permeability apparatus used in this test consists of a permeability cell, which is a rigid cylinder made of austenitic stainless steel. The apparatus also includes a disk made of noncorroding metal that fits snugly inside the cell, as well as a plunger made of austenitic stainless steel. Circular filter paper disks with smooth edges, having the same diameter as the inside of the cell, are used in the apparatus. A U-tube manometer, filled with a nonvolatile and nonhygroscopic liquid of low viscosity and density, is used to measure the pressure difference across the cement bed. A timer with a positive starting and stopping mechanism is also required.

The standard emphasizes the importance of calibration and standardization of the air permeability apparatus. The calibration should be done using the standard reference material. In the case of automated apparatus, the qualification requirements should be met, and if standardization is necessary to achieve agreement between Test Method A and Test Method B, it should be carried out according to the requirements specified in the standard.

It should be noted that while this test method has been primarily used for the fineness determination of portland cements, it may also be applicable to other materials. However, the user should exercise judgment to determine its suitability for fineness measurements of cements with different densities or porosities than the standard reference materials specified.

A warning is also provided regarding the use of mercury in the apparatus. Mercury is considered a hazardous substance, and caution should be taken when handling mercury and mercury-containing products. Users should refer to the applicable product Safety Data Sheet (SDS) for additional information on handling and safety precautions. It is important to comply with any regulations regarding the use and sale of mercury in the specific state or country.