Dakota MAX II, Operation Manual

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CHAPTER ONE
INTRODUCTION
The Dakota Ultrasonics model MAX II is used to measure the stretch (elongation,
load, stress and %strain) of a fastener under tension. This is accomplished
ultrasonically by sending an ultrasonic wave down the length of the fastener and
accurately measuring the change in transit time between an unloaded versus loaded
fastener/bolt, and calculating a physical stretch. The objective for using ultrasonics,
over conventional/mechanical methods is accuracy. Most conventional methods
refer to a torque value which has limited accuracy due to the coefficient of friction.
The coefficient of friction is difficult to determine, as it depends on the control and
application of lubrication.
The MAX II avoids the coefficient of friction entirely, using the transit time of a wave,
Hooke’s law, and Young’s modulus to accurately calculate the stretch on a bolt.
Since the
MAX II cannot physically stretch a bolt, both conventional/mechanical
methods and the MAX II are complimentary and used in conjunction.
Dakota Ultrasonics maintains a customer support resource in order to assist users
with questions or difficulties not covered in this manual. Customer support may be
reached at any of the following:
Dakota Ultrasonics Corporation
1500 Green Hills Road, #107
Scotts Valley, CA 95066 USA
Telephone: (831) 431-9722
Facsimile: (831) 431-9723
www.dakotaultrasonics.com
1.1 General Disclaimer
The manual should be read and understood prior to using the MAX II . This operating
manual provides the user with all the general information necessary to use and adjust
the designed features. However, this manual is not a certified NDT/Bolting training
course, nor is it intended to be one. Training, according to company requirements, is
recommended. The responsibility for proper use of the instrument rests solely on the
user.
1.2 Safety
Using the MAX II while standing in water or in a wet environment can result in serious
electric shock, injury, and even death.
Operating the MAX II with damaged or inadequate cables and power source can
result in serious electric shock, injury, and even death.