Ultrasonic Stress Meter

As design engineers push the envelope to provide greater strength and efficiency in bolted joints, the use of torque, torque and angle, or even tensioning as the method of tension control may not be adequate, leading to costly failures.
In those applications, ultrasonic bolt elongation/load measurement is able to provide accuracy equal to strain gauging without the need to strain gauge a bolt.



Delta Sigma InstrumentUSM III-instrument

In addition, the use of ultrasonic bolt measurement allows the user to return at any
time and re-verify the level of tension in each fastener over its service life. The Delta Sigma or USM-3 has been both laboratory and field-proven to be the most accurate, reliable and cost effective solution to bolting failures which could place workers at risk, lead to the loss of production and/or cause damage to capital equipment.


About Ultrasonic Load tensioning measurement

The basic principle behind this method of tension control is similar to sonar. The ultrasonic measurement of bolt tension is achieved by introducing a sonic pulse at one end of the fastener and accurately measuring the time of flight (TOF) required for the echo to return from the opposite end. Using material constants, the instrument converts this TOF into an “acoustic length” of the fastener, providing a baseline from which future measurements will be made.When the fastener is tightened: the TOF increases and the instrument will again utilize material constants to eliminate the effects of stress and temperature variations on sound velocity, providing an accurate elongation or load measurement.
The instruments uses state of the art hardware and digital signal processing to achieve these measurements with maximum automation, minimizing the need for operator interpretation. Once measurements have been recorded to the instruments internal memory, it is possible to transfer the data to a computer for backup of files, creation of project reports, and conversion of data to Excel format for further analysis. In addition, the analogue signal output can be used to automatically shut-off powered torque and tensioning tools based on elongation or load, in even the most demanding applications.

 40334Ultrasonic Stress Meter (USM3)
DS-1Delta Sigma instrument (DS)
 TDC-10-LM3m transducer cable 

 Art.noDescription A 
 560163/16" 5 MHz Magnetic transducer   9,7 13 54 29
 560091/4" 5 MHz Magnetic transducer   19 19 60 35
 560101/2" 5 MHz Magnetic transducer   25 19 60 35
 560123/4" 5 MHz Magnetic transducer   30 19 60 35
 560213mm 7,5 MHZ Glue on transducer  N/A N/A N/A N/A



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