Freezing Point of Engine Coolants

Description

Determines the exact temperature of the onset of ice crystal formation in antifreeze, ensuring the protection of the engine and radiator from bursting in winter.

When severe frosts hit, hydrometers and portable refractometers at service stations can show an error, but the laws of physics cannot. Analyzing the actual freezing point of antifreeze at the RENA laboratory is the only 100% reliable way to know if your engine block or industrial chiller pipes will burst this winter. We measure not the density, but the real physical crystallization point. This test allows logistics companies, builders, and fleets to sleep peacefully, knowing the exact frost resistance limit of their coolant. According to the ASTM D1177 standard (or equivalent), the test requires constant stirring and precise temperature control. A coolant sample is placed in a special double-walled glass tube, which is immersed in a powerful liquid cryostat (AFPplus cooling bath). Inside the sample, a mechanical wire stirrer works continuously to prevent supercooling without crystallization, and a high-precision platinum thermal sensor takes readings every second. The instrument automatically builds a «temperature-time» cooling curve in real time. As the solution cools, when the first microscopic ice crystals begin to form (the mixture becomes cloudy), the latent heat of crystallization is released. Because of this, the temperature drop on the graph stops for a moment, forming a clear horizontal plateau (or a noticeable break in the curve). The intersection point of these curves is recorded as the absolutely precise freezing point.