Ultrasonic Bolt Measurement

Bolt Torquing & Tensioning services are only as good as the quality control processes that supervise them. On critical flanges, control of the bolt preload is essential to the performance of the flange. 

• A bolt load that is too low will not ensure suitable gasket stress is maintained to affect a seal.  The result is leakage.
• A bolt load that is too high will result in damage to the flange, bolt or gasket, resulting in leakage.

The only way to be absolutely sure that the specified bolt load is achieved in a bolted assembly is to measure the stretch.  The only practical way to do that is with precision bolt load monitoring. Every other method is guesswork and guessing can be dangerous, costly and could lead to unscheduled shutdowns.  Ultrasonic verification instantly provides digitized read-out of the true bolt load.

State-of-the-art ultrasonic bolt measurement equipment, such as the MINI-MAX, Ultrasonic Bolt Tension Monitor, allows you to know exactly what bolt load is retained. SPEEDORANGE™ provides the The MINI-MAX, measures the actual elongation produced by tightening a threaded fastener.  The MINI-MAX can measure the elongation very accurately in fasteners of virtually any material from 1/2 inch to 4 feet in length. 

The measurement is achieved by determining the change in the transit time, of an ultrasonic shock wave along the length of the fastener as the fastener is tightened by any method.  The on-board microcomputer automatically interprets this time measurement to display the time (nanoseconds), elongation, load, stress, or %strain from stretching a fastener. The hand-held units are portable and battery operated with a high resolution VGA display. Using Windows® software, the technician is able to download measurements, create reports, and upload test parameters–sending reports direct to the printer. The units store 8,000 readings and waveforms with a built-in linear regression, and high/low alarm tolerance to work with data ports and pump shutoffs.