Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Process for performing casting under negative pressure condition

A technology of casting process and conditions, applied in the field of casting, can solve problems such as difficulty in filling, non-empty cavity, and impact on the quality of castings

Inactive Publication Date: 2011-09-14
TSINGHUA UNIV
View PDF9 Cites 5 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0002] Investment casting is a widely used casting technology. Its advantages include good surface quality of the inner cavity of the mold shell, high dimensional accuracy, and high-quality precision castings with complex shapes due to hot casting. However, Difficulties in mold filling are still encountered when pouring castings with particularly complex shapes or alloys with poor filling ability
For easy-to-oxidize alloys, there is also the problem of secondary oxidation of molten metal; lost foam casting directly embeds the foam plastic mold in the dry sand of the sand box, pours metal under negative pressure, and the metal interacts with the foam plastic mold. The pyrolysis of the foam plastic mold is to complete the mold filling, but because the cavity is not empty during the lost foam casting, the pyrolysis products of the foam plastic mold will affect the quality of the casting

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
  • Process for performing casting under negative pressure condition
  • Process for performing casting under negative pressure condition

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0011] As shown in the accompanying drawings, the casting process method under the negative pressure condition of the present embodiment, at first prepare the shell 1 with the gate 6 by the investment casting method, and the shell 1 is baked to the predetermined time for 30 minutes to the predetermined time. After the calcination temperature is 1050°C, cool to room temperature and then put it into the heat-resistant flask 2 with the air outlet 4, or place the mold shell 1 prepared by investment casting method directly in the heat-resistant flask with the air outlet 4 2, fill the gap between the shell 1 and the heat-resistant sand box 2 with refractory heat-insulating sand 3, cover the surface of the refractory heat-insulation sand 3 with a heat-resistant sealing layer 5 with a preset thickness, and seal the gate of the shell 1 6. The upper part is exposed on the heat-resistant sealing layer 5. Such mold shell 1, heat-resistant sand box 2, refractory insulating sand 3 and heat-r...

Embodiment 2

[0013] As shown in the accompanying drawings, the casting process method under the negative pressure condition of the present embodiment, at first prepare the shell 1 with the gate 6 by the investment casting method, and the shell 1 is baked to the predetermined time for 30 minutes to the predetermined time. After the calcination temperature is 1050°C, cool to room temperature and then put it into the heat-resistant flask 2 with the air outlet 4, or place the mold shell 1 prepared by investment casting method directly in the heat-resistant flask with the air outlet 4 2, fill the gap between the shell 1 and the heat-resistant sand box 2 with refractory heat-insulating sand 3, cover the surface of the refractory heat-insulation sand 3 with a heat-resistant sealing layer 5 with a preset thickness, and seal the gate of the shell 1 6. The upper part is exposed on the heat-resistant sealing layer 5. Such mold shell 1, heat-resistant sand box 2, refractory insulating sand 3 and heat-r...

Embodiment 3

[0015] As shown in the accompanying drawings, the casting process method under the negative pressure condition of the present embodiment, at first prepare the shell 1 with the gate 6 by the investment casting method, and the shell 1 is baked to the predetermined time for 30 minutes to the predetermined time. After the calcination temperature is 1050°C, cool to room temperature and then put it into the heat-resistant flask 2 with the air outlet 4, or place the mold shell 1 prepared by investment casting method directly in the heat-resistant flask with the air outlet 4 2, fill the gap between the shell 1 and the heat-resistant sand box 2 with refractory heat-insulating sand 3, cover the surface of the refractory heat-insulation sand 3 with a heat-resistant sealing layer 5 with a preset thickness, and seal the gate of the shell 1 6. The upper part is exposed on the heat-resistant sealing layer 5. Such mold shell 1, heat-resistant sand box 2, refractory insulating sand 3 and heat-r...

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

No PUM Login to View More

Abstract

The invention discloses a process for performing casting under a negative pressure condition. In the method, the advantages of investment casting and lost foam casting are combined, the high-quality casting mould of investment casting is used, and pouring is performed under a thermal condition; by using a negative pressure technology of a lost foam, the negative pressure environment is formed around the investment casting mould, and the secondary oxidation of metal is reduced; and metal filling is promoted and the feeding capacity of molten metal is improved by using the pressure difference between the casting mould and a pouring gate, so that a high-quality casting is obtained, and a large-sized casting can be cast.

Description

technical field [0001] The invention belongs to the technical field of casting, and in particular relates to a casting process method under negative pressure conditions. Background technique [0002] Investment casting is a widely used casting technology. Its advantages include good surface quality of the inner cavity of the mold shell, high dimensional accuracy, and high-quality precision castings with complex shapes due to hot casting. However, When casting castings with particularly complex shapes or alloys with poor filling ability, it is still difficult to fill the mold. For easy-to-oxidize alloys, there is also the problem of secondary oxidation of molten metal; lost foam casting directly embeds the foam plastic mold in the dry sand of the sand box, and pours metal under negative pressure, and the metal and the foam plastic mold will interact. The pyrolysis of the foam plastic mold is to complete the filling, but because the cavity is not empty during the lost foam ca...

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
IPC IPC(8): B22D18/00
Inventor 吕志刚崔旭龙林阳阳
Owner TSINGHUA UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com