International Bolting Technologies Inc.



USM 3 - USM-3 Ultrasonic Bolt Meter -  bolt stress meterUSM-3

The USM-3 Ultrasonic Stress Meter measures load and elongation in fasteners, tie bars and shafts of virtually any material from 1/2 inch to over 50 feet in length. Know the precise load, elongation or stress on your critical bolts. Track preload changes over any time period from minutes to years.

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The Norbar USM-3 Ultrasonic Bolt Meter, released in 2007 to replace the USM-II, is the world's most versatile instrument for the measurement of the actual clamp load in a fastener. The USM-3 can measure bolt preload or elongation extremely accurately in bolts of virtually any material from 1/2" (12mm) to over 50' (15m) in length; and from 5mm to over 36" (914mm) in diameter.

Through the use of digital signal processing and automated signal diagnostics the USM-3 minimizes operator training and preparation. The Norbar USM-3 provides state of the art hardware and software to achieve measurements with maximum automation, minimizing operator interpretation. Offering digital recordation and transmission of data, as well as calibrated analog signal output, the USM-3 offers a complete system for measurement, recordation, and control of bolt tension in the most demanding applications.


Size: 9-7/16” (239mm)W x 7-1/16” (180mm)H x 2-1/16” (53mm)D
Weight: 4.95 lb (2.25 kg)
Keypad: Membrane switch with tactile keys.
Display: ¼ VGA backlit. 3-7/8”(98mm)W x 3”(76mm)H
Case: Sealed Aluminium.
Battery Power: 4 'C' Cells
Optional Line Power: 96-264 VAC 47 to 63 Hz.
Operating Temperature: 32°F to 110°F (0 to 43°C). Automatic Compensation for Temperature of Fastener.
Calibration: Automatic verification of system calibration Field verification of bolt material calibration constants.
Data Transfer:
9 Pin RS232 I/O.
Analog Output:
150 Pin 0 to 10 V Scalable
Resolution: 0.00001 inch (0.0001mm).
General: Pitch catch, pulse echo measurement modes. Automatic peak signal and phase selection.
Pulser: 160 volt push/pull tone burst. Selectable burst width. Selectable frequencies 1.0, 2.25, 5.0, 7.5 and 10 MHz
Receiver: Low noise preamplifier. Automatic gain control. Automatic waveform and signal diagnostic display.
Timing: 160 MHz 10 ppm TCXO controlled digitizer.
Memory: Non-volatile. Stores data on 4000 bolts, (5 elongations and 5 loads per bolt).
2 YEAR LIMITED WARRANTY Norbar Torque Tools web site


International Bolting Technologies Inc.

IBT Bolting Hotline: 1-407-923-3724

Phone: 386-774-1184

Fax: 386-774-5648

Corporate Headquarters: P.O. Box 740617 • Orange City, FL 32774




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