Lawler Model DR4 Series Automatic Freezing Point Tester
The automated Freeze Point Analyzer fully conforms to ASTM D2386 method. All dimensions are as specified by D2386. The sample is agitated by a wound wire, which is driven by a magnetically operated motor. The sample is poured into the receiver. The sample is automatically fed into the test tube, the start button is pressed, and the test begins. The bath is then cooled at a rate such that the sample-cooling rate equals the cooling rate of the manual method.
When the test is completed, the apparatus is automatically warmed, the old sample is gravity drained from the test tube (by actuation of a solenoid valve), the fresh sample flushes the test tube and a new test is started.
Fiber optics reflects light from a C shaped mirror immersed in the test sample. When reduced light is detected the first freezing point is determined. The sample is warmed and the fiber optics detects the melting point.