Detection method of closed surface fatigue crack

A detection method and technology for fatigue cracks, which can be used in measuring devices, solid analysis using sound waves/ultrasonic waves/infrasonic waves, and material analysis using sound waves/ultrasonic waves/infrasonic waves.

Inactive Publication Date: 2006-06-28
SHANGHAI BAOSTEEL IND TECHNOLOGICAL SERVICE
View PDF0 Cites 8 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Due to the influence of the inner sleeve of the bearing, the use of surface magnetic particle testing (MT) or coloring penetrant testing (PT) cannot meet the requirements for detecting fatigue cracks on the surface of the roll neck

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
  • Detection method of closed surface fatigue crack
  • Detection method of closed surface fatigue crack

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0010] A method for detecting fatigue cracks on a closed surface, using the ultrasonic pulse reflection method to detect shaft defects by emitting ultrasonic waves from a direction perpendicular to the end face of the roll neck; and receiving detection signals by a probe with a small diffusion angle and good directivity. It can be displayed on the screen of the flaw detector, and the position and equivalent size of the defect can be obtained according to the echo signal. Among them, the instruments used are the latest SS240 and MS340 flaw detectors developed by the British SONATEST company. These two instruments have high precision, and when detecting flaws under high sensitivity conditions, the electric noise of the instrument is extremely low, the waveform signal is stable, and the operation is simple. Probe selection to meet site requirements is another important part. Ultrasonic vibration frequency is much higher than audible sound waves, and is generated by the transduce...

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

A method for detecting fatigue crack of closed surface includes emitting ultrasonic wave towards end surface vertical to roller neck to carry out detection on defects of shafts, using probe with small diffusion angle and excellent directional property to receive detection signal and displaying it on screen of crack detector, obtaining position and equivalent size of defect according to echo signal.

Description

[0001] Field [0002] The detection method for closed surface fatigue cracks of the invention relates to a method for non-destructive detection of shafts or forgings. Background technique [0003] Aiming at a Baosteel cold rolling mill in 2001, there were two accidents of roll neck breakage of the smooth back-up roll, which caused production stoppage and equipment damage, and also brought great economic losses to production. The support roller adopts rolling bearing structure. The roll neck is cylindrical without taper, and the root of the roll neck is the part where the back-up roll bears the maximum bending moment. A bearing inner sleeve is installed on the roll neck to completely cover the roll neck surface. Due to the requirements of use and maintenance, it is sometimes necessary to disassemble the inner sleeve of the bearing. Since the assembly of the inner sleeve and the roll neck adopts an interference fit, the inner sleeve needs to be heated during disassembly. The...

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): G01N29/06G01N29/24
Inventor 张晨红
Owner SHANGHAI BAOSTEEL IND TECHNOLOGICAL SERVICE
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