SU1477505A1 - Sand for producing casting moulds and cores in heated tooling - Google Patents

Abstract

The invention relates to a foundry, in particular, to mixture compositions for the manufacture of casting molds and cores in a heated tooling. The purpose of the invention is to improve the quality of the molds and cores by reducing their brittleness while maintaining the technologically required strength characteristics in the hot and cold state. The composition of the mixture. wt.%: carbamide-furan binder 1.5 ... 3.0

acid curing catalyst 0.3 ... 1.0

boric acid 0,2 ... 0,4

granulated slag from the production of ductile iron 5.0 ... 15.0

refractory filler else. The chemical composition of granulated slag, wt.%: Calcium oxide 25 ... 40

aluminum oxide 6 ... 10

manganese oxide 1,5 ... 3,0

iron monoxide 5 ... 10

iron oxide 2 ... 3

magnesium oxide 2 ... 3

silicon dioxide the rest. Due to the implementation of the invention, the fragility of the mixture is reduced by 15 ... 20% and preventing the formation of cuts and burns on cast iron castings. 1 hp f-ly, 2 tab.

Description

Granulated slag from the production of ductile iron has a fraction size of about 0.05-0.1 mm and the following chemical composition, wt.%:

Calcium oxide 25-40 Aluminum oxide 6-10 Manganese oxide 1.5-3.0 Iron oxide Iron oxide 2-3 Mg oxide 2-3 Silicon dioxide Remaining A mixture of a given composition was prepared as follows. In periodical runners, the refractory filler, granulated granular boric acid is mixed for 2 minutes, then the curing catalyst is introduced into the mixture and mixing is continued for 1.5 minutes, after which the binder is added and mixed for another 1, 5 minutes. The total mixing cycle is 5 minutes. The mixture preparation technology is common to all ingredient ratios.

The compositions of the proposed mixtures are given in table.1.

The mode of hot curing: the heating temperature of the equipment is 220 ± 5 ° C, the duration of holding the mixture in the equipment is 30 s,

The survivability of the mixture was determined by the magnitude of its fluidity depending on the storage time of the sample of the mixture in a closed container. The measurements were carried out after 1 h for 5-6 h.

The presence of perforations on the technological sample was determined visually.

bending of the hardened mixture by 15–20% and, accordingly, reduce its brittleness. Due to this, the formation of notches of the type of notches and burns is prevented.

Claims (2)

Invention Formula 101. Mixture for the manufacture of casting molds and cores in a heated snap-in containing refractory filler, carbamide-organic binder, acidic curing catalyst 15 and boric acid, characterized in that, in order to improve the quality of the molds and cores by reducing their fragility while maintaining the required technological indices of strength in the hot and cold state, the mixture additionally contains granulated slag from the production of ductile iron in the following ingre ratio of 25 dientes, wt%: Urea-furan binder-1.5-3.0 Acidic curing catalyst 0.3-1.0 30 Borna acid 0.2-0.4 Granulated slag from malleable production cast iron5.0-15.0 35Fireproof fillerOther 2. A mixture of pop. 1, which differs from the fact that granular The slag from the production of malleable iron. The presence of burns on castings has the following chemical composition, tavitel x was determined visually. Properties of the mixtures listed in table 1, are given in table 2. The brittleness of the cores and shapes is estimated by the flexural strength index. The implementation of the proposed invention allows to increase the comp.%: Calcium Oxide 25-40 Aluminum oxide 6-10 Manganese Oxide1.5-3.0 45 ferrous oxide 5-10 Iron oxide2-3 Magnesium oxide 2-3 Silicon dioxide Else bending of the cured mixture by 15-20% and, accordingly, reduce its brittleness. Due to this, the formation of defects of the type of perforations and burns is prevented. Invention Formula 01. Mixture for the manufacture of casting molds and cores in a heated snap-in containing refractory filler, carbamide-fluorine binder, acid curing catalyst 5 and boric acid, characterized in that, in order to improve the quality of the molds and cores by reducing their fragility when maintaining the required technological indices of strength in the hot and cold state, the mixture additionally contains granulated slag from the production of ductile iron in the following ratio of ingredients, wt.%: Urea-furan binder-1.5-3.0 Acidic curing catalyst 0.3-1.0 0 Borna acid 0.2-0.4 Granulated slag from malleable production cast iron5.0-15.0 5Fireproof fillerOther 2. A mixture of pop. 1, which differs from the fact that granular The slag from the production of ductile iron to has the following chemical composition, wt.%: Calcium Oxide 25-40 Aluminum oxide 6-10 Manganese Oxide1.5-3.0 5 ferrous oxide 5-10 Iron oxide2-3 Magnesium oxide 2-3 Silicon dioxide Else Table 1 Ingredients The content of ingredients, wt.%, In a mixture zrzn Urea-furanovoy binder KF-90 Catalyst CC-41 Borna acid 2.5 0.4 0.4 1.5 0.3 0.3 3.0 1.0 0.3 Granulated putty from forged iron production 5,010,015,010,010,0 Refractory filler 91.9 86.8 91.7 87.9 85.7 Tensile strength, MPa: in the hot state 0.48 0.48 0.48 0.46 0.54 in the cold state 2.15 2.14 2.12 2.30 2.90 Bending strength, MPa, in a cold state 9.3 9.3 9.3 9.4 9.3 The presence of perforations on the process sample No No No No No The presence of burns on the iron castings No No No No No Continuation of table 1 table 2