Steel moulding sand and manufacturing technology thereof

Abstract

The invention discloses a steel moulding sand and a manufacturing technology thereof. The steel moulding sand is composed of steel beads, phenolic resin, a curing agent, and a lubricant, wherein the phenolic resin, the curing agent and the lubricant are coated on the surfaces of the steel beads. The manufacturing technology of the steel moulding sand comprises the following operation steps: (1) slowly and evenly pouring molten steel liquid onto a roller through a ladle, wherein the lower edge of the roller is soaked in water in a water pool, when the steel liquid falls onto the roller surface with water, numerous micro steel beads are formed and fall into the water pool; (2) fishing out the steel beads, drying the steel beads by baking, and then screening out steel beads with a diameter of 0.20 to 0.85 mm; (3) putting 100 kilograms of steel beads with the same size into a heater, heating the steel beads until the temperature reaches a temperature of 95 to 105 DEG C, at the same time starting a film-coating and sand-mixing machine, orderly adding phenolic resin, a curing agent, and a lubricant into the film-coating and sand-mixing machine, when the temperature of the coated steel beads reaches 70 DEG C or less, discharging the steel beads from the machine. The heat conductive coefficient of the steel moulding sand is high, so the steel moulding sand can accelerate the solidifying speed of iron water to make the iron water around the steel moulding sand solidify firstly, and plays the role as a chilling block. Moreover, the cost of the steel moulding sand is lower, the manufacturing technology of the steel moulding sand is simple, and thus the manufacturing cost is low.

Description

Technical field: [0001] The invention relates to a new type of molding sand for making cores and a manufacturing process of the molding sand. Background technique: [0002] At present, the general core-making process is to use coated sand to make the required sand core manually or mechanically, and the sand core matches the shape to cast various castings. The coated sand mainly uses high-quality selected natural quartz sand as the raw sand, and the surface of the raw sand is coated with thermoplastic phenolic resin, urotropine and reinforcing agents. According to the different technical requirements of users, the ratio of coating materials can be adjusted appropriately in terms of curing speed, release property, fluidity, collapsibility, surface finish of castings, storage, etc. The thermal conductivity of this kind of coated sand is low. In order to avoid the uneven cooling rate of various parts of the same casting, shrinkage cavities may occur, or the parts with thin wall...

AI Technical Summary

Problems solved by technology

[0004] The present invention aims at the low thermal conductivity of the existing coated sand and the need to be equipped with cold iron, etc.,

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