ASTM D6660 for Freezing Point of Aqueous Ethylene Glycol Base Engine Coolants
ASTM D6660 Standard Test Method for Freezing Point of Aqueous Ethylene Glycol Base Engine Coolants by Automatic Phase Transition Method
6. Apparatus
6.1 Automatic Apparatus - The apparatus described in this method consists of a test chamber controlled by a microprocessor that is capable of cooling and heating the test specimen, optically observing the appearance and disappearance of solid crystals and recording the temperature of the specimen.

6.2 The apparatus shall be equipped with a specimen cup, optical detector array, light source, digital display, Peltier device and a specimen temperature measuring device.

6.3 The temperature measuring device in the specimen cup shall be capable of measuring the temperature of the test specimen from -80°C to +50°C at a resolution of 0.1°C.

6.4 The apparatus shall be equipped with fittings to permit the circulation of liquid cooling media to remove heat generated by the Peltier device and other electronic components of the apparatus.

7. Reagents and Materials
7.1 Cooling Media - Liquid heat exchange media to remove the heat generated by the Peltier device and other electronic components from the apparatus.

NOTE 3 - Some apparatus are designed to use tap water as cooling media to bring specimen temperature to -60°C. To achieve cooling of specimen to -80°C, provide circulation of liquid cooling media at -30°C or lower to the apparatus. Refer to manufacturer's operating instructions on the relationship between cooling media temperature and the minimum specimen temperature.

7.2 Adjustable Volume Pipette, capable of dispensing 0.15 ± 0.01 ml of sample.

7.3 Cotton Swabs - Plastic or paper shaft cotton swabs to clean the specimen cup.

NOTE 4 - Caution: The use of swabs with wooden shafts may damage the mirrored surface of the specimen cup.