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

Method for improving point-like cavitation erosion resistance of hydraulic turbine runner by rare earth treatment

A water turbine and rare earth technology, which is applied in the field of steel materials and its products, can solve the problems of adverse effects on the safe service of water turbine runner parts, harsh service conditions, etc., and achieve good process feasibility, low cost, and improved cavitation resistance. Effect

Inactive Publication Date: 2019-11-15
INST OF METAL RESEARCH - CHINESE ACAD OF SCI +1
View PDF2 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0003] However, as the power of the turbine runner continues to increase and the service conditions become more and more stringent, scattered point-like cavitation often occurs in the turbine runner components, and the occurrence of this phenomenon has an adverse effect on the safe service of the turbine runner components

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
  • Method for improving point-like cavitation erosion resistance of hydraulic turbine runner by rare earth treatment
  • Method for improving point-like cavitation erosion resistance of hydraulic turbine runner by rare earth treatment
  • Method for improving point-like cavitation erosion resistance of hydraulic turbine runner by rare earth treatment

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0045] In this implementation, ZG04Cr13Ni4Mo steel is commonly used as the upper crown, lower ring and blades of large water turbine runners.

[0046] The specific implementation process is as follows:

[0047] The traditional process is to use the LF furnace for smelting, and then use the VOD furnace for refining treatment. When the oxygen content and sulfur content of the molten steel are lower than 40ppm and 80ppm respectively, it is poured into the sand mold through the protective pouring method, and the molten steel is cooled and solidified to form a casting. , The castings are machined after normalizing + tempering treatment to reach the delivery state.

[0048] In the embodiment of the present invention, in the middle and late stages of the VOD treatment of molten steel, when the oxygen content is 20ppm and the sulfur content is 50ppm, the mixed rare earth lanthanum cerium is added to the molten steel according to the content of 100g per ton of steel by means of pressin...

Embodiment 2

[0051] In this implementation, ZG04Cr13Ni5Mo steel is commonly used as the upper crown, lower ring and blades of large water turbine runners.

[0052] The specific implementation process is as follows:

[0053] The traditional process is to use the LF furnace for smelting, and then use the AOD furnace for refining treatment. When the oxygen content and sulfur content of the molten steel are lower than 40ppm and 80ppm respectively, it is poured into the ingot mold through the protective pouring method, and the molten steel is cooled and solidified to form Electrode blanks, and then electroslag casting to manufacture blades, the castings are machined after normalizing + tempering to reach the delivery state.

[0054] In the embodiment of the present invention, in the middle and later stages of the AOD treatment of molten steel, when the oxygen content is 30ppm and the sulfur content is 72ppm, lanthanum metal is added to the molten steel by pressing in according to the content of...

Embodiment 3

[0057] This implementation is the 304 austenitic stainless steel used in the upper crown, lower ring and blades of the large water turbine runner.

[0058] The specific implementation process is as follows:

[0059] The traditional process is to use the LF furnace for smelting, and then use the AOD furnace for refining treatment. When the oxygen content and sulfur content of the molten steel are lower than 40ppm and 80ppm respectively, it is poured into the ingot mold through the protective pouring method, and the molten steel is cooled and solidified to form The electrode blank is then electroslag casted to produce the blade blank, and then heated to about 1000 ° C, and molded with a mold, and then the forging is machined after solution treatment to reach the delivery state.

[0060] In the embodiment of the present invention, in the middle and later stages of the AOD treatment of molten steel, when the oxygen content is 35ppm and the sulfur content is 75ppm, cerium metal is ...

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
oxygen contentaaaaaaaaaa
Login to View More

Abstract

The invention belongs to the fields of steel materials and products of the steel materials, particularly provides a method for improving point-like cavitation erosion resistance of a hydraulic turbinerunner by rare earth treatment, and is suitable for improving the point-like cavitation erosion resistance of hydraulic turbine runner castings / forgings by changing the number and types of inclusionsin a material. When molten steel of the hydraulic turbine runner castings / forgings including crowns, bands and blades is smelted with traditional VD, VOD and AOD methods, on the basis of controllingthat total oxygen content of refined molten steel is not higher than 40 ppm and S content is not higher than 80 ppm, lanthanum, cerium pure metal or lanthanum and cerium alloy with oxygen content nothigher than 150 ppm is added to the molten steel according to the addition amount of 100-500 g per ton of steel in the later period of VD, VOD and AOD, and then soft blowing treatment is performed for20 min. Under the action of treated metamorphic inclusions, the problem of local point-like cavitation erosion induced under high-speed water current scouring when the hydraulic turbine runner castings / forgings are on service is solved; by means of solid soluble rare earth, pitting corrosion point locations of the material are increased, so that the phenomenon of local point point-like cavitationerosion caused by pitting corrosion is avoided.

Description

technical field [0001] The invention belongs to the field of iron and steel materials and their products, in particular to a method for improving the anti-point cavitation performance of a hydraulic turbine runner through rare earth treatment. Background technique [0002] As the most mature renewable energy power generation technology, hydropower is widely used around the world, meeting more than 20% of the world's current electricity demand, and more than half of the electricity in more than 55 countries is provided by hydropower. In a hydropower station, the turbine runner is the core component of water energy-kinetic energy conversion, which drives the mover in the generator to rotate under the high-speed impact of the water flow, thereby achieving the goal of power generation. Under the impact of high-speed water flow, cavitation corrosion (cavitation erosion for short) is the most common and most harmful failure mode of turbine runner components. The occurrence of cav...

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): C21C7/00C21C7/06C21C7/064
CPCC21C7/0006C21C7/06C21C7/064
Inventor 王培张成平刘功梅王长罡李殿中董俊华李文学刘洁
Owner INST OF METAL RESEARCH - CHINESE ACAD OF SCI
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