Quick spheroidizing annealing technology for GCr15 bearing steel pipe

A bearing steel pipe, spheroidizing annealing technology, applied in the field of bearing steel pipe production, can solve the problems of large carbide dispersion, dense carbide, affecting the dispersion degree of spheroidized structure, etc., and achieve the effect of inhibiting precipitation

Active Publication Date: 2013-08-07
ZHEJIANG JIANLI CO LTD
View PDF4 Cites 6 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

It should be pointed out that although some cooling rates (50°C / h) can still obtain qualified spheroidized structures, this spheroidized structure is not excellent, because the cooling rate affects the dispersion of the spheroidized structure, and the cooling rate is fast, carbonization Large particle dispersion, resulting in dense carbides in local areas, and its spheroidizing effect is not as good as cooling at a rate of ≤200°C / h

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
  • Quick spheroidizing annealing technology for GCr15 bearing steel pipe

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0026] Such as figure 1 The graph of a kind of embodiment of the present invention shown, GCr15 bearing steel pipe fast spheroidizing annealing process, comprises the following steps:

[0027] 1) After hot-rolling and piercing, the GCr15 bearing steel pipe with a final rolling temperature of 950-1000°C is quickly cooled to 550-650°C through a controlled cooling device, and then air-cooled to room temperature for the first time;

[0028] 2) Spheroidize the GCr15 bearing steel pipe that has been air-cooled for the first time to 795°C±10°C for the first heat preservation;

[0029] 3) Slowly cool the GCr15 bearing steel pipe after the first heat preservation to 760°C±10°C for the first time;

[0030] 4) The GCr15 bearing steel pipe that has been slowly cooled for the first time is quickly cooled to 725°C ± 10°C for the second time;

[0031] 5) Carry out the second heat preservation of the GCr15 bearing steel pipe after the second quick cooling;

[0032] 6) Slowly cool the GCr15...

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 quick spheroidizing annealing technology for a GCr15 bearing steel pipe. The technology comprises the following steps of: performing water passing quick cooling on the hot-rolled perforated GCr15 bearing steel pipe with the final rolling temperature of between 950 and 1,000 DEG C through a controlled cooling device to the temperature of between 550 and 650 DEG C, and performing first air cooling to room temperature; spheroidizing and heating the GCr15 bearing steel pipe to the temperature of 795+ / -10 DEG C after the first air cooling is finished, and performing firstheat preservation; performing first slow cooling to the temperature of 760+ / -10 DEG C; performing second quick cooling to the temperature of 725+ / -10 DEG C; performing second heat preservation; performing second slow cooling to the temperature of 680+ / -10 DEG C; performing furnace cooling to the temperature of 650+ / -10 DEG C; and finally, discharging and performing second air cooling. The technology has the advantages of effectively shortening the retention time of the netlike carbide precipitation interval, inhibiting the precipitation of netlike carbides, obtaining good spheroidized structure in short time and greatly shortening the spheroidizing time.

Description

technical field [0001] The invention relates to the field of bearing steel pipe production, in particular to a GCr15 bearing steel pipe rapid spheroidizing annealing process. Background technique [0002] Bearings are widely used in mechanical products and engineering structures. Bearing steel must undergo spheroidizing annealing after hot rolling to make the carbides completely globalized. The carbides are evenly distributed on the ferrite matrix in the form of smaller spheroids. The structure has good machinability, low overheating sensitivity, and the residual carbides after quenching and tempering are fine and evenly distributed, so the bearing steel has high wear resistance, bending fatigue strength, and impact toughness. The rolling process has a significant impact on the microstructure of GCr15 bearing steel. In the production process of large-section bearing steel bars, there are problems that it is difficult to achieve low-temperature final rolling and control cooli...

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 Patents(China)
IPC IPC(8): C21D8/10C21D9/08
Inventor 赵健孙国均陈志跃王正德胡彬任蜀焱阳辉
Owner ZHEJIANG JIANLI 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

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