Post on 02-Jan-2016
description
Optical Monitoring and Control of Bolt Tightening
Dr. Sayed Nassar, AdvisorAidong Meng
Objectives and Methodology• Develop optical monitoring and control method for bolt tightening• Use 3-D Electronic Speckle Pattern Interferometry technique • Establish Torque-Tension-Deformation correlation • Determine a proper clamp load and tightening strategy
3-D Electronic Speckle Pattern Interferometric sensor
Results
Test Setup
Nut
Load Cell
Test Coupon
M12 Bolt
Fastener Head
Schematic of single bolt joint
The bolted joint is fixed by a vice
Out-of-plane deformation field corresponding to 26 KN clamp load
Deformation profile along line L1
Deformation profile along line L2
0
0.2
0.4
0.6
0.8
1
1.2
1.4
0 5 10 15 20 25 30
Clamp load F(KN)
Def
orm
ation
w(u
m)
Bolt 1
Bolt 2
Bolt 3
Bolt 4
Bolt 5
Bolt 6
Tension-deformation correlation
z y
x
Laser
Beamsplitter
PZT
CCD array Lens
Reference
beam
Object beam
Measuring direction
Before loading
After loading
Measuring
object
Schematic diagram of ESPI for out-of-plane deformation measurement