There are many critical bolting applications where the measurement of applied torque alone will not provide the necessary control of actual fastener tension as required by engineers. Ultrasonic measurement of fastener elongation and/or bolt tension is recognised as one of the most effective solutions for accurate, reliable and cost effective control in this critical area.
The Norbar ultrasonic stressmeter can be employed to monitor the tension of fasteners over their service life giving huge benefits in predictive and preventative maintenance. The determination of optimum bolting processes can also be assessed by the USM-3 under varying friction conditions and changes in bolt/joint geometry.
State of art hardware and software is employed by the USM-3 to give optimum automation whilst also providing strict signal confirmation that ensures precise results. Management of data is conveniently handled by direct connection of the USM-3 to standard PC’s in conjunction with our web sourced ‘Sonic Bolt’ software.
The USM-3 stressmeter can effectively test fasteners over a wide range of diameters and lengths using a range of varying transducer sizes and frequencies.
Since the USM-3 has both battery and mains power facilities it is portable and extremely versatile for use on all engineering sites.
- USM-3’s ¼VGA backlit LCD display provides easy to interpret results of load, elongation data and waveform. Norbar’s exclusive five-point DSP algorithm also provides an evaluation of signal quality.
- USM-3 can provide a 0-10V analogue output to precisely shut off torque tools when a predetermined bolt stretch or load has been attained.
- The onboard flash memory can store measurements on up to 80 bolts, with up to five measurements of load and elongation for each bolt.
- An RS232 interface allows these results to be uploaded to a PC where Norbar’s Windows-based Sonic Bolt software can perform theoretical load to stretch calculations for long-term mechanical joint integrity analysis. The software can also provide Excel-formatted reports.
The USM-3 is an evolution of Norbar’s popular USM-2, with significant improvements in both utility and performance. The new model offers eight times more memory and twice the processor speed as the previous model, for increased capacity and faster response. In addition, the 1/4VGA display is significantly larger than that of the USM-2, allowing more data to be presented and in a more user-friendly fashion.