METHOD FOR DETERMINING PLASTICITY INDEX OF SAND AND CORE SAND MIXTURES Russian patent published in 2019 - IPC B22C1/00 

FIELD: technological processes.

SUBSTANCE: invention relates to metallurgy. To determine the plasticity index, a sample of the mixture is taken, sieved through a sieve and placed in a standard sleeve. Removable liner without holes is installed at the bottom of the sleeve. Sample of the mixture is precompacted in a compaction unit and the H₀ height of the resulting sample is measured. Removable liner of the sleeve is replaced with a liner with four holes and compacts the sample with three strokes. After each stroke, the height of the sample is fixed. Determination of the plasticity index is carried out according to the formula: IP_l=(H₁+H₂+H₃)/H₀, where H₀ – height of the sand or core sand mixtures after pre-compaction, mm; H₁, H₂ and H₃ – the height of the sample of the sand or core sand mixtures after each of the three seals of the sample, mm.

EFFECT: increased reliability of the evaluation of the plastic properties of liquid-movable, plastic, sand-clay, self-hardening, liquid-glass mixtures, curing by drying is provided.

1 cl, 3 dwg, 2 tbl, 1 ex