Abstract: The Model ZC-20B tester developed wish the principle of thermal analysis and the technology of microcomputer has the advantages of high testing speed, high precision, low cost and convenient use. The tester can be used in front of the cupola and electrical furnace to test cast iron liquid quality and the testing results include 20 parameters such as characteristic temperature points on the cooling curve, chemical composition, mechanical property, eutectic cells number,nodular graphite grade and so on. In the paper,the general structure of the tester,the design method of the sampling holder, the data acquizition system and the mathematic models are introduced.

Key words: multiparameters, intelligent instrument, cast iron liquid quality