Check patentability & draft patents in minutes with Patsnap Eureka AI!

Method for preventing cracking of ceramic mold shell in dewaxing process

A technology of dewaxing process and ceramic mold, which is applied in the direction of mold, core, mold composition, etc., and can solve the problems of ceramic mold shell cracking, dewaxing cracking, etc.

Inactive Publication Date: 2018-03-09
DONGFANG TURBINE CO LTD
View PDF11 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] The present invention is aimed at the above problems and provides a method for solving the cracking of the ceramic shell during the dewaxing process.
In this method, we propose a pretreatment for the mold shell, which truly solves the problem of dewaxing and cracking physically, without additional cost, and is of great promotion value

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

Embodiment 1

[0019] A method for solving the cracking of a ceramic shell in the dewaxing process, which includes the following steps:

[0020] 1) Use conventional techniques for wax mold pressing, wax mold assembly, dipping, sand showering and drying;

[0021] 2) Put the dried ceramic shell into the freezer, the freezer temperature is set to -10℃, and the freezing time is 6 hours;

[0022] 3) Quickly transfer the frozen ceramic shell to the high temperature and high pressure steam dewaxing kettle for dewaxing, the transfer time is 20 seconds, the dewaxing temperature is 172°C, and the dewaxing time is 5 minutes;

[0023] 4) Put the dewaxed shell into a heating furnace, heat it to 750°C at a temperature increase rate of 300°C / h, keep it for 2 hours, and then cool it naturally to 200°C after keeping it warm.

[0024] By adopting the above process steps, it is completely avoided that a certain type of turbine blade mold shell has cracks in the dark riser guide channel and the exhaust edge R part during...

Embodiment 2

[0026] Such as Example 1: The temperature of the freezer compartment is set to -15°C, the freezing time is 4 hours, and other process parameters remain unchanged. It is used for a certain type of turbine blade single crystal mold shell, which completely solves the problem of crystal selection during the dewaxing process. The problem of cracks in the part of the device.

Embodiment 3

[0028] As recorded in the method in Example 1: Ignore the pre-freezing process in step 2), and other process parameters remain unchanged. In the batch dewaxing module, the blade mold shell is in the dark riser drainage channel and the exhaust edge R part during the dewaxing process. All have serious cracks.

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 belongs to the field of precision casting of fired molds and particularly relates to a method for preventing cracking of a ceramic mold shell in a dewaxing process. According to the method, the ceramic mold shell is pre-frozen by virtue of an advanced counteractive principle before dewaxing, and a shrinkage gap is formed in advance by virtue of the difference of thermal expansion coefficients of a wax material and a ceramic material so as to compensate a space occupation requirement on the swelling of the wax material during high-temperature and high-pressure dewaxing, so that the cracking of the ceramic mold shell is avoided. By virtue of the pretreatment aiming at the mold shell, the cracking problem in the dewaxing process is truly and physically solved, and additional cost is not required, so that the method has a very high promotional value.

Description

Technical field [0001] The invention belongs to the field of investment precision casting, and is specifically a method for solving the cracking of a ceramic shell in the dewaxing process. Background technique [0002] The investment casting process is complicated, including wax mold pressing, wax mold assembly, dipping, sand showering, drying, dewaxing, roasting, pouring and post-processing. In the process of dipping, sanding and drying, the slurry and sand are tightly covered on the surface of the wax mold layer by layer, forming a ceramic shell green on the surface of the wax mold. After the drying is completed, the wax mold in the ceramic shell blank is melted in a high-temperature steam dewaxing kettle. In the dewaxing process, since the thermal expansion coefficient of the wax mold is greater than the thermal expansion coefficient of the mold shell, the ceramic mold shell is prone to cracks, resulting in scrap. Therefore, it is now necessary to solve the problem of ceram...

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): B22C9/12B22C9/04
CPCB22C9/12B22C9/04
Inventor 曾洪张松泉伍林杨功显胡维成杨照宏巩秀芳赵代银何建
Owner DONGFANG TURBINE CO LTD
Features
  • R&D
  • Intellectual Property
  • Life Sciences
  • Materials
  • Tech Scout
Why Patsnap Eureka
  • Unparalleled Data Quality
  • Higher Quality Content
  • 60% Fewer Hallucinations
Social media
Patsnap Eureka Blog
Learn More

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

© 2025 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com