Ultrasonic Instruments

With accuracy rivaling that of strain-gauges, the USM-3, Ultrasonic Bolt Meter, defines the state of the art in the measurement of the actual clamp load produced by tightening a threaded fastener. The USM-3 can measure fastener elongation or the resulting load, very accurately in fasteners of virtually any material from 1/2 inch to over 50 feet in length.

The USM-3 allows up to 30 hours field operation from 4 'C' cell alkaline batteries.

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 elongation or load in the fastener. Through the use of high speed digital signal processing and automated diagnostics, the USM-3 minimizes the requirements for extensive operator training.

Technical Specification
• Weight: 2.25 Kg (4.95 lb) with batteries.
• Resolution: 0.0001 inch (0.001 mm)
• Dimensions: 180 mm high x 239 mm wide x 53 mm deep.
• Accuracy of Elongation:: +/-0.0003 in (+/-0.008 mm) or 0.001% of reading if greater.

Features
• Large 1/4 VGA back lit display is easily visible from a distance and in poor light.
• Can store up to 2000 measurements.
• Rugged steel and aluminium case designed for production and site environments.
• USM 3 is supplied in a rugged water tight (Pelican(R)) case complete with AC adaptor, nylon carrying case, 6' transducer cable, RS232 data transfer cable, 4 oz bottle of couplant and operation handbook.
• Measures fasteners of virtually any material from 1/2 inch (12mm) to over 50 feet (17m) in length.
• 0 - 10V analogue output for control of tightening tools such as a Norbar Pneutorque multiplier.
• Measurement modes of pitch-catch and pulse-echo.
• Unit can be operated with mains power supply or via 4 'C' cell batteries.
• Sealed membrane keypad with tactile keys.
• Works with magnetic and glue on transducers from 1 MHz to 10 MHz.