Casting sand core repairing paste and preparation method thereof

Abstract

The invention relates to casting sand core repairing paste and a preparation method of the casting sand core repairing paste. The casting sand core repairing paste comprises the following components in percentage by weight: 65%-70% of washed-out sand, 8%-10% of fine sand, 3%-5% of pregelatinized starch, 2%-3% of sodium bentonite, 0.2%-0.5% of cellulose, 0.1%-0.5% of fatty alcohol-polyoxyethylene ether and the balance of water. The preparation method comprises the following steps: preparing cellulose turbid solution from the cellulose and the water; preparing sodium bentonite solution from the sodium bentonite and the water, and adding the cellulose turbid solution, so as to prepare a suspension solution; adding the prepared suspension solution, the water and the pregelatinized starch into a high-speed stirring kettle, uniformly stirring, adding the fine sand, the washed-out sand and the alcohol-polyoxyethylene ether into the high-speed stirring kettle, and uniformly stirring, so as to obtain the casting sand core repairing paste. The preparation method has the advantages that the preparation process is simple, raw materials are easily available, the gas evolution is low, pores are reduced, the repairing paste and a sand core are synchronously scattered, castings are easy to clean, and a sand adhering phenomenon is prevented.

Description

Technical field [0001] The invention relates to a foundry sand core repair paste and a preparation method thereof. Background technique [0002] The casting production process is generally divided into sand processing, modeling, core making, drying, molding, smelting, pouring, and falling sand cleaning. In actual production, about half of casting products require core making, so core making is an important part of the casting process. The use of core shooting mechanism is a highly efficient mechanized core making method, which uses compressed air as the driving force to inject the core sand into the core box at high speed to obtain a compact sand core. After the sand core is made, it is fixed in a specific position in the sand mold for pouring. After the casting is completed, the sand core is wrapped in the casting and the sand core is broken to form a cavity in the casting. [0003] In the core making process, due to the accuracy of tooling equipment, temperature control, raw an...

AI Technical Summary

Problems solved by technology

[0004] At present, the commonly used repair pastes are mainly divided into the following types: one is made of raw materials such as engine oil and bentonite; because the engine oil contains a large amount of raw materials and produces a lot of gas, it has a large amount of gas, and the oily smoke is large during pouring. Castings are prone to defects such as pores

The other is made of phosphorus flake graphite, which is prepared by adding a binder; because phosphorus flake graphite is used as a raw material, it is easy to shell, fall off, and conduct electricity during use, so the casting is prone to sand sticking, pores, etc. after pouring. Casting defects, not suitable for automated casting lines

There is also a kind of quartz powder, which is prepared by adding binder and suspending agent. After pouring, it is easy to adhere to the surface of the casting and is not easy to collapse, resulting in difficult cleaning of the casting and defects such as sticky sand.