Measuring and testing – Vibration – By mechanical waves
Patent
1981-07-20
1983-11-08
Kreitman, Stephen A.
Measuring and testing
Vibration
By mechanical waves
73597, 73631, G01N 2900
Patent
active
044135181
ABSTRACT:
A bolt elongation measurement apparatus and method for measuring the length of bolts of all sizes and shapes. The apparatus utilizes a microprocessor-based digital system including a binary counter which counts pulses generated by a high frequency oscillator during the time interval between the entry into the bolt of a first pulse and exit from the bolt of a second pulse derived from the reflection return of ultrasonic energy from the opposite end of the bolt. The count is applied to a computer for calculation of bolt length or of bolt stretch due to mechanical stress. The calculation also incorporates data input via thumbwheel switches and corresponding to material velocity, stress correction factor, measurement temperature, and thermal correction factor. A unique digital filtering algorithm ensures an accurate and stable measurement. The receiver of the apparatus overcomes the problem of spurious ultrasonic reflection characteristics of threaded bolts by means of a dual characteristic echo sensing circuit to deal with stress-induced pulse distortion and a unique gain contour circuit to deal with spurious echo pulses that are characteristic of threaded bolts.
REFERENCES:
patent: 3759090 (1973-09-01), McFaul et al.
patent: 3918294 (1975-11-01), Makino et al.
patent: 3969810 (1976-07-01), Pagano
patent: 3985022 (1976-10-01), Dileo
patent: 4102205 (1978-07-01), Pies et al.
Kreitman Stephen A.
NDT Instruments, Inc.
LandOfFree
Apparatus and method for measuring the extension of bolts under does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Apparatus and method for measuring the extension of bolts under , we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Apparatus and method for measuring the extension of bolts under will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2002455