3D printing precoated sand molding process

A 3D printing and molding technology, applied in casting molding equipment, molds, cores, etc., can solve the problems of insufficient strength, stability, high temperature resistance, poor high temperature resistance and poor high temperature resistance of coated sand, and achieve Low rupture rate, fast hardening rate, effect of reducing rupture rate

Active Publication Date: 2018-07-20
LIUZHOU LIUJING TECH CO LTD
View PDF6 Cites 5 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, due to the lack of strength, stability, and high temperature resistance of the coated sand used in the traditional casting process, it has become an inevitable trend to use 3D printed coated sand instead of traditional coated sand in 3D printing technology.
[0005] Chinese Patent No. "201510602060.5" discloses a preparation method of 3D printing rapid prototyping coated sand. The disadvantage is that the coated sand obtained by molding has poor high temperature resistance and high rupture rate.
Therefore, there is an urgent need for a molding process of 3D printing coated sand to solve the problems of poor high temperature resistance and high rupture rate of coated sand in 3D printing in the prior art

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

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • 3D printing precoated sand molding process
  • 3D printing precoated sand molding process

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0028] In this embodiment, the 3D printing coated sand molding process includes the following steps:

[0029] A. Rinse the raw sand with water for 30 minutes and put it in a constant temperature drying oven at 60°C to dry;

[0030] B, soak the raw sand after above-mentioned drying in the sulfuric acid solution and carry out pickling 30min process, the raw sand after the pickling is rinsed with clear water and then dry again, obtain the pretreated raw sand after passing through a 60 mesh sieve;

[0031] C. Add the above-mentioned pretreated raw sand into a sand mixer with a temperature of 150°C and a speed of 300 rpm, and add calcium stearate with a mass of 3% of the mixed sand, and then mix the sand for 20 minutes, and then slowly cool down the sand mixer After reaching 140°C, add a curing agent of 5% of the mass of the mixed sand, continue to stir for 10 minutes and then stand still for 30 minutes; after standing still, slowly cool the sand mixer to 80°C, add an inorganic bin...

Embodiment 2

[0038] In this embodiment, the 3D printing coated sand molding process includes the following steps:

[0039] A. Rinse the raw sand with water for 50 minutes and put it in a constant temperature drying oven at 70°C to dry;

[0040] B, soak the raw sand after above-mentioned drying in the sulfuric acid solution and carry out pickling 30min process, the raw sand after the pickling is rinsed with clear water and then dry again, obtain the pretreated raw sand after passing through a 60 mesh sieve;

[0041] C. Add the above-mentioned pretreated raw sand into a sand mixer with a temperature of 300°C and a speed of 500 rpm, and add calcium stearate with a mass of 7% of the mixed sand, and then mix the sand for 20 minutes, and then slowly cool down the sand mixer After reaching 140°C, add a curing agent with a mass of 10% of the mixed sand, continue to stir for 10 minutes and then stand still for 40 minutes; after standing still, slowly cool the sand mixer to 100°C, add an inorganic b...

Embodiment 3

[0048] In this embodiment, the 3D printing coated sand molding process includes the following steps:

[0049] A. Rinse the raw sand with water for 35 minutes and then put it in a constant temperature drying oven at 62°C to dry;

[0050] B, soak the raw sand after above-mentioned drying in the sulfuric acid solution and carry out pickling 30min process, the raw sand after the pickling is rinsed with clear water and then dry again, obtain the pretreated raw sand after passing through a 60 mesh sieve;

[0051] C. Add the above-mentioned pretreated raw sand into a sand mixer with a temperature of 180°C and a speed of 350 rpm, and add calcium stearate with a mass of 4% of the mixed sand, and then mix the sand for 22 minutes, and then slowly cool down the sand mixer After reaching 140°C, add a curing agent with a mass of 6% of the mixed sand, continue to stir for 10 minutes and then stand still for 32 minutes; after standing still, slowly cool the sand mixer to 85°C, add an inorgani...

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
flexural strengthaaaaaaaaaa
Tensile strengthaaaaaaaaaa
Login to view more

Abstract

The invention discloses a 3D printing precoated sand molding process. The 3D printing precoated sand molding process comprises the following steps: (A) raw sand is washed by water; (B) the raw sand iswashed by acid; (C) the raw sand is mixed with an auxiliary to obtain mixed sand; (D) the mixed sand is injected into a mold through a core injector; (E) steam is introduced into the mold to obtain a3D printing precoated sand semi-finished product; and (F) the 3D printing precoated sand semi-finished product is put in a hot air drying box for hot air drying curing to obtain molded 3D printing precoated sand. The 3D printing precoated sand molding process is simple; and the obtained precoated sand is high in strength and excellent in high-temperature resistance, so that the quality of 3D printing workpieces can be improved, no environmental pollution is caused, and energy conservation and environmental protection are achieved. The steam introduction step can be adopted to improve the filmcoating uniformity of the raw sand; and then, the hot air drying is performed for drying curing of sand models, so that the hardening speed is high, and the rupture rate of the precoated sand is reduced.

Description

technical field [0001] The invention belongs to the technical field of coated sand molding, and in particular relates to a 3D printing coated sand molding process. Background technique [0002] Coated sand: Molding sand or core sand whose surface is covered with a layer of solid resin film before molding. There are two kinds of coating processes: cold method and hot method: the cold method dissolves the resin with ethanol, and adds urotropine during the sand mixing process, so that the two are coated on the surface of the sand, and then evaporates the ethanol to obtain the coating. Coated sand: Preheat the sand to a certain temperature by thermal method, add resin to melt it, stir to coat the resin on the surface of the sand, add urotropine aqueous solution and lubricant, then cool, crush and sieve to obtain coated sand. Coated sand is mainly used to prepare steel castings, iron castings, etc. [0003] 3D printing is a technology that uses bondable materials such as powder...

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): B22C9/02B22C1/16B22C9/12B22C1/10
CPCB22C1/10B22C1/167B22C9/02B22C9/123
Inventor 任文强
Owner LIUZHOU LIUJING TECH CO LTD
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