Method for preparing high-temperature-resisting anti-crack precoated sand through composite resin

A composite resin and high-temperature-resistant technology, which is applied in manufacturing tools, casting molding equipment, metal processing equipment, etc., can solve the problems of poor heat resistance, poor material coordination, and low gas generation of coated sand, and achieve long heat resistance time , high hardening rate, low gas generation effect

Inactive Publication Date: 2017-05-31
丁玉琴
View PDF11 Cites 5 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] The main technical problem to be solved by the present invention is that the existing coated sand has poor heat resistance and is prone to cracking when casting castings with relatively complex structures, especially when casting thin-walled castings, which are more likely to crack and have poor material coordination. The defect is to provide a method for coating the composite resin made of epoxy resin modified phenolic resin on the surface of the mixed sand after surface treatment, and curing to form coated sand. In the present invention, firstly, the quartz sand and waste ceramics are mixed and sieved. Mix it with a slurry made of glutinous rice and water, freeze-dry it after wet ball milling, and sieve it to obtain a dry powder, then react the formaldehyde solution with phenol and oxalic acid to obtain a phenolic resin, dissolve it in absolute ethanol to obtain a phenolic resin ethanol solution, Then pour the dry powder, gypsum powder, dimethyl silicone oil, etc. into the sand mixer and mix, then add hexamethamine solution and epoxy resin E-51 to stir and react, and add dropwise phenolic resin ethanol solution and dibromocresyl glycidol Ether is solidified, cooled to room temperature after solidification and unloaded to obtain high-temperature resistant and crack-resistant coated sand. The coated sand prepared by the present invention has good curing effect, high strength, low gas generation, and excellent high temperature resistance. Good performance and material coordination, not easy to break when casting castings, and can meet the production requirements of various complex precision castings

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Examples

Experimental program
Comparison scheme
Effect test

example 1

[0016] First, weigh 400g of quartz sand, 3g of diatomaceous earth, 4g of silicon carbide, 8g of polyester fiber and 50g of waste ceramics, put them into a ball mill and mill them for 2 hours and pass through a 300-mesh sieve to obtain a mixed powder, then weigh 50g of glutinous rice and add them to 800g of water. After mixing, move it into a beater, beat at a speed of 18000r / min for 15min, pass through 200 meshes after beating to obtain a slurry, mix the mixed powder and slurry at a mass ratio of 1:5, and perform wet ball milling for 40min, discharge after ball milling, and freeze-dry After passing through a 200-mesh sieve, dry powder was obtained for subsequent use; then 80g of formaldehyde solution with a mass fraction of 37% and 120g of phenol were weighed and added to a four-necked flask, and then 1g of oxalic acid was added, and after mixing, the four-necked flask was moved into an oil bath. Raise the temperature to 90°C, stir and react for 2 hours, cool to 70°C after the ...

example 2

[0019] First, weigh 450g of quartz sand, 4g of diatomaceous earth, 5g of silicon carbide, 9g of polyester fiber and 55g of discarded ceramics, add them into a ball mill and mill them for 3 hours and pass through a 310-mesh sieve to obtain a mixed powder, then weigh 75g of glutinous rice and add them to 900g of water. After mixing, move it into a beater, beat at a speed of 19000r / min for 18 minutes, pass through 220 mesh after beating to obtain a slurry, mix the mixed powder and slurry at a mass ratio of 1:5, and perform wet ball milling for 50 minutes, discharge after ball milling, and freeze-dry Pass through a 210-mesh sieve to obtain a dry powder for subsequent use; then weigh 90g of 37% formaldehyde solution and 135g of phenol into a four-necked flask, then add 2g of oxalic acid, and move the four-necked flask into an oil bath after mixing. Raise the temperature to 100°C, stir and react for 2 hours, cool to 75°C after the reaction, mix the materials in the four-neck flask wi...

example 3

[0022] First, weigh 500g of quartz sand, 5g of diatomaceous earth, 6g of silicon carbide, 10g of polyester fiber and 60g of waste ceramics, put them into a ball mill and mill them for 4 hours and pass through a 320-mesh sieve to obtain a mixed powder, then weigh 100g of glutinous rice and add them to 1000g of water. After mixing, move it into a beater, beat at a speed of 20000r / min for 20min, pass through 240 mesh after beating to obtain a slurry, mix the mixed powder and slurry at a mass ratio of 1:5, and perform wet ball milling for 60min, discharge after ball milling, and freeze-dry After passing through a 220-mesh sieve, dry powder was obtained for subsequent use; then 100g of formaldehyde solution with a mass fraction of 37% and 150g of phenol were weighed and added to a four-necked flask, and then 3g of oxalic acid was added, and after mixing, the four-necked flask was moved into an oil bath. Raise the temperature to 110°C, stir and react for 3 hours, cool to 80°C after t...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
thicknessaaaaaaaaaa
strengthaaaaaaaaaa
thermal resistanceaaaaaaaaaa
Login to view more

Abstract

The invention discloses a method for preparing high-temperature-resisting anti-crack precoated sand through composite resin, and belongs to the technical field of preparation of precoated sand. The method for preparing the high-temperature-resisting anti-crack precoated sand through the composite resin comprises the steps that quartz sand and waste ceramic are ground in a mixed mode, sieved and then mixed with pulp prepared from sticky rice and water, an obtained mixture is freeze-dried and sieved through wet ball-milling, and thus dry powder is obtained; afterwards, a formaldehyde solution reacts with phenol and oxalic acid, so that phenolic resin is obtained; the phenolic resin is dissolved in absolute ethyl alcohol, so that a phenolic resin-ethanol solution is obtained; and the dry powder, gypsum powder, simethicone and the like are poured into a sand mixer so as to be mixed, a urotropin solution and epoxy resin E-51 are added for a stirring reaction, the phenolic resin-ethanol solution and dibromotoluene glycidyl ether are added dropwise for a curing reaction, cooling is conducted till the room temperature is reached after curing, sand discharging is conducted, and thus the high-temperature-resisting anti-crack precoated sand is obtained. The precoated sand prepared through the method is good in curing effect and high in strength, has the excellent performance of low gas evolution and high temperature resistance, is good in material coordination and not prone to breakage when a casting is cast, and can meet production requirements of various complex precision castings.

Description

technical field [0001] The invention discloses a method for preparing high-temperature-resistant and crack-resistant coated sand with a composite resin, and belongs to the technical field of coated sand preparation. Background technique [0002] With the rapid development of the automobile industry and the need for foreign trade export of mechanical products, as well as the development of the casting international market, the requirements for casting quality are getting higher and higher, such as the improvement of casting surface and dimensional accuracy, the increase of thin-walled castings, the reduction of internal defects of castings, etc. , Coated sand refers to the molding sand or core sand covered with a layer of solid resin on the surface of the sand grains before molding. Because the coated sand has strong adaptability, high strength, low gas generation, high dimensional accuracy of the produced castings, smooth surface and easy storage In recent years, it has been...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): B22C1/00B22C1/22
CPCB22C1/00B22C1/2233
Inventor 丁玉琴孙冬葛明月
Owner 丁玉琴
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products