Method for forging screw and nut

A nut and screw technology, applied in the field of forging, can solve the problems of failure to meet the standard, very high performance requirements of forgings, localization of screws and nuts, etc., and achieve the effect of improving reliability and meeting technical requirements

Active Publication Date: 2010-07-07
上海新闵重型锻造有限公司
View PDF0 Cites 9 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0003] At present, castings and forgings used in million-kilowatt nuclear power construction projects, such as screws and nuts used for steam generators in pressurized water reactor nuclear power plants, have very high performance requirements for forgings due to their special service environment. General heat treatment methods not up to standard
At present, the above-mentioned screws and nuts used in the steam generator of the PWR nuclear power plant cannot be localized, and they are mostly ordered from abroad.

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 forging screw and nut

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0031] Embodiment 1: the requirement of manufacturing process among the present embodiment is:

[0032] 1. Forging:

[0033] a) heating the steel ingot to 700°C and keeping it warm for 3h; then heating it for 3h to make the temperature reach 1150°C and keeping it warm for 1h;

[0034] b) In the temperature range of 1150°C-850°C, upsetting and elongating the workpiece generated in step b), and then straightening, correcting the size, and rounding to make the forging ratio greater than 4, so as to forge the screw rod and The body of the nut.

[0035] 2. Performance heat treatment: When the surface temperature of the body after forging is not higher than 600°C, heat the green body to 980°C and keep it for 1h, cool it with oil to not higher than 100°C, then reheat it to the temperature range of 700°C and keep it for 3h , and then water-cooled.

[0036] Process requirements for performance heat treatment: immerse the green body in the oil tank, the immersion depth is ≥1.5M and m...

Embodiment 2

[0038] Embodiment 2: the requirement of manufacturing process among the present embodiment is:

[0039] 1. Forging:

[0040] a) heating the steel ingot to 700°C and keeping it warm for 3h; then heating it for 3h to make the temperature reach 1150°C and keeping it warm for 1h;

[0041] b) In the temperature range of 1150°C-850°C, upsetting and elongating the workpiece generated in step b), and then straightening, correcting the size, and rounding to make the forging ratio greater than 4, so as to forge the screw rod and The body of the nut.

[0042] 2. Performance heat treatment: When the surface temperature of the body after forging is not higher than 600°C, heat the body to 980°C and keep it warm for 1.5h, cool it with oil to not higher than 100°C, then reheat it to a temperature range of 705°C and keep it warm 3h, then water cooled.

[0043] Process requirements for performance heat treatment: immerse the green body in the oil tank, the immersion depth is ≥1.5M and move b...

Embodiment 3

[0045] Embodiment 3: the requirement of manufacturing process among the present embodiment is:

[0046] 1. Forging:

[0047] a) heating the steel ingot to 700°C and keeping it warm for 3h; then heating it for 3h to make the temperature reach 1150°C and keeping it warm for 1h;

[0048] b) In the temperature range of 1150°C-850°C, upsetting and elongating the workpiece generated in step b), and then straightening, correcting the size, and rounding to make the forging ratio greater than 4, so as to forge the screw rod and The body of the nut.

[0049] 2. Performance heat treatment: When the surface temperature of the body after forging is not higher than 600°C, heat the green body to 980°C and keep it for 2 hours, cool it with oil to not higher than 100°C, then reheat it to the temperature range of 710°C and keep it for 3 hours , and then water-cooled.

[0050] Process requirements for performance heat treatment: immerse the green body in the oil tank, the immersion depth 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
diameteraaaaaaaaaa
lengthaaaaaaaaaa
lengthaaaaaaaaaa
Login to view more

Abstract

The invention relates to the technical field of forging, in particular to a method for forging a screw and a nut for a steam generator of a pressurized water reactor nuclear power station. The method comprises the following steps: repeatedly performing upsetting-stretching on a suitable steel ingot at the temperature of between 1,150 and 800 DEG C to ensure that the forging ratio is no less than 4; and then sequentially performing property heat treatment and machining after the heat treatment on the steel ingot to obtain the screw and the nut. The method has the advantages that: performance indexes of the screw and the nut meet the requirements of a RCC-M standard; using requirements of the screw and the nut for the steam generator of the pressurized water reactor nuclear power station are met; the safety and the reliability of the screw and the nut are greatly improved, and technical requirements of the products are met.

Description

technical field [0001] The invention relates to the technical field of forging, in particular to a forging method for a screw and a nut used in a steam generator of a pressurized water reactor nuclear power plant. Background technique [0002] In recent years, power shortage has become a bottleneck restricting the sustained and rapid development of China's economy. As an important measure to save energy and adjust energy structure, nuclear power has been included in the national power development plan. The development of my country's nuclear power industry has a history of more than 30 years. It has always been based on the research and trial production of small-scale nuclear power equipment, and has not formed mature manufacturing technology and production equipment capabilities. Therefore, the development of nuclear power in our country is developing in the direction of high power. [0003] At present, castings and forgings used in million-kilowatt nuclear power construct...

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): B21K1/44B21K1/64C22C38/32B21J1/06C21D9/00
Inventor 王兴中王元华
Owner 上海新闵重型锻造有限公司
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

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

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap