Eureka AIR delivers breakthrough ideas for toughest innovation challenges, trusted by R&D personnel around the world.

A method for detecting the pretightening force of high-strength bolts

A technology of high-strength bolts and detection methods, applied in force/torque/work measuring instruments, measuring torque/torsional force during tightening, measuring devices, etc., can solve problems such as difficulty in use, wave speed error, etc. The effect of stable excitation frequency and stable measurement results

Active Publication Date: 2022-04-01
XIANGTAN UNIV
View PDF7 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Otherwise, small changes in contact conditions and measurement positions will cause major errors in wave velocity, so it is difficult to use in actual engineering

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
  • A method for detecting the pretightening force of high-strength bolts
  • A method for detecting the pretightening force of high-strength bolts
  • A method for detecting the pretightening force of high-strength bolts

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0031] The present invention will be further specifically described below in conjunction with the accompanying drawings and embodiments.

[0032] See Figure 1~ Figure 8 , the detection method of high-strength bolt preload provided by the invention specifically comprises the following steps:

[0033] (1) Select a model with a bolt diameter of 16mm, according to the actual situation of high-strength bolts in steel structure engineering (such as Figure 1a Shown) Set the elastic modulus (Ε), density (ρ), Poisson's ratio (μ) of the relevant material, and establish high-strength bolts at different preloads in COMSOL Multiphysics (that is, the preload reaches the high-strength bolt 0, 10%, 20%, 30%, 40%, 50%, 60%, 70% of the tensile strength design value) when the finite element model, using material parameters as shown in Table 1:

[0034] Table 1

[0035] Elastic modulus (GPa) Density(kg / m3) Poisson's ratio steel plate 200 7850 0.3 bolt 209 7850 ...

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 detection method for the pretightening force of high-strength bolts. The acoustic characteristics of high-strength bolts and nuts are studied, the received pulse signal is processed, and the time-domain signal of the pulse signal is normalized. Then the power function fitting is carried out to obtain the relationship between the pre-tightening force of high-strength bolts and the fixed-point acoustic time t, so that the magnitude of the pre-tightening force of high-strength bolts can be obtained according to the fixed-point acoustic time t. The method for detecting the pretightening force of high-strength bolts proposed by the invention has portable equipment and high detection efficiency, and provides a convenient, accurate and quick measurement method for detecting the pretightening force of high-strength bolts.

Description

technical field [0001] The invention relates to the field of acoustic wave detection, in particular to a detection method for the pretightening force of high-strength bolts. Background technique [0002] At present, steel structure buildings have been widely used in civil buildings and plant construction, and steel structures have shown a particularly important posture in the construction field. High-strength bolt connection is a steel structure node connection method developed in the middle of the 20th century. With the improvement of the performance of structural materials and the manufacturing capacity of standard parts, high-strength bolts are more and more used in engineering. The connection quality of high-strength bolted connections is particularly important to the stability of steel structures. When the pre-tightening force is too large, the strength of the high-strength bolts will be damaged; if the pre-tightening force is too small, the joints will be loose. 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 Patents(China)
IPC IPC(8): G01L5/24
CPCG01L5/246
Inventor 龙士国许文宗赵朴凡
Owner XIANGTAN UNIV
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
Eureka Blog
Learn More
PatSnap group products