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

Device and method used for measuring axial bolt relaxation in consideration of joint surface characteristics

A joint surface and bolt technology, which is used to measure the direction of torque/torsional force during tightening, can solve the problems of unmeasurable contact surface changes, complex structure, and low measurement accuracy

Inactive Publication Date: 2017-09-22
BEIJING UNIV OF TECH
View PDF7 Cites 19 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0008] In order to solve the problems of complex structure, low measurement accuracy, unmeasured contact surface changes during relaxation and unclear relationship between relaxation and vibration displacement in existing devices

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
  • Device and method used for measuring axial bolt relaxation in consideration of joint surface characteristics
  • Device and method used for measuring axial bolt relaxation in consideration of joint surface characteristics
  • Device and method used for measuring axial bolt relaxation in consideration of joint surface characteristics

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0034]Step 1: Scan the contact area of ​​the upper connector 2 and the lower connector 5 with different processing quality through a three-dimensional surface topography measuring instrument and establish a corresponding database, including 3D topography, three-dimensional coordinates, surface roughness, and waviness and other parameters as the initial reference value of the contact surface features. Start the tensile testing machine 1 for preheating; the pressure sensor 7, digital amplifier, data acquisition card and computer are connected in sequence, and the initial value is set to zero by software setting; the pressure sensor 7 is worn on the screw rod 6; The upper connecting piece 5 and the lower connecting piece 2 under the surface quality are connected by the screw rod 6 and the nut 3, so that the pressure sensor 7 forms a series connection between the screw rod 6 and the upper connecting piece 5; the different torques of the torque wrench are controlled to control the b...

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
pore sizeaaaaaaaaaa
Login to View More

Abstract

The invention discloses a device and method used for measuring axial bolt relaxation in consideration of joint surface characteristics, which belongs to the field of mechanical manufacturing and structural mechanics. A bolt bar passes through upper and lower connectors, and contact surfaces have specific size and surface data. A pressure sensor is used to measure the attenuation of the bolt clamping force. An eddy current displacement sensor is used to measure displacement between the contact surfaces. Three-dimensional topography scanning is used to measure the surface three-dimensional data. A tensile testing machine is used to carry out cyclic tensile test and simulate the bolt conditions. The axial clamping force and axial displacement are transmitted to a computer for recording and processing through a data acquisition system. Axial bolt relaxation characteristics are acquired by analysis and processing several kinds of data. According to the invention, the connection characteristic of an axial part is ensured; the influence of a fixed joint surface on bolt relaxation is considered; and the bolt relaxation test precision is improved.

Description

technical field [0001] The invention relates to a device and method for measuring the looseness of axial bolts in consideration of joint surface characteristics, and belongs to the fields of mechanical manufacturing and structural mechanics. Background technique [0002] The surfaces where parts contact each other are joint surfaces. Bolt relaxation is the process in which the clamping force of a bolt fastener with a certain pretightening force decreases under alternating load conditions, which is called bolt relaxation. There are many factors affecting bolt relaxation, one of which is that the characteristics of the joint surface affect the initial pre-tightening force of the bolt and the attenuation of the clamping force under vibration conditions. Fundamentally speaking, the combined interplanetary characteristics are the contact characteristics of the rough asperity and the contact stiffness and contact damping of the components formed by the contact of the bolts. Scho...

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): G01L5/24
CPCG01L5/24
Inventor 蔡力钢刘强刘志峰李迎吕华峰徐文祥
Owner BEIJING UNIV OF TECH
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