Both methods described in the Standards give a relative measure of the plastic behaviour of coal when heated at constant rate, under prescribed conditions.
Fluidity of coal is obtained applying a constant torque on a stirrer placed in a crucible loaded with the coal, heating the crucible in a molten solder bath furnace and recording stirrer movement on a dial drum graduated into 100 divisions, D.D.P.M. (Dial Division per Minute) in relation to increase of temperature.
All the analysis procedure, even up and down movement of the crucible, is automatic: the operator needs only to mount the crucible and to start the system.
The double furnace system productivity is considerably increased due to the reduction of heating and cooling waiting times.
Once started, PL 2000 will preheat the furnace, check the correct loading of the sample, lower the crucible, restore the start temperature, raise the temperature at uniform rate and carry out the fluidity test.
Drum dial movement is recorded by means of an optical encoder with a resolution of 0.2 D.D.P.M.
Furnace temperature together with fluidity readings are displayed and printed out during the test.