Swept frequency type of ultrasonic inspection method for linear- propellant seperation of the H-I upper-stage motors

Two steel substrate test panels were developed to represent common plate thicknesses found on naval vessels and scanned using the Babcock developed ultrasonic technique. One sample comprised of a series of slotted surface breaking flaws of varying widths and through thicknesses to represent fracturing/cracking. The inspection method detected simulated cracking to a depth of 2mm and 0.5mm in width. The second sample included numerous loss of wall thickness areas of varying diameters and through thicknesses, with the smallest detectable loss of wall thickness being 0.1mm at a 15mm diameter. After proving confidence in detection, there was a need to characterise flaws to provide support and ascertain a repair action. Samples were produced that were subjected to either impact or heat exposure to induce realistic representative damage. The practical ultrasonic method was successfully used to independently characterise between the samples, with induced de-laminations caused by blisters, and multi layered matrix cracking caused by varying levels of projectile impacts, due to their unique morphology.

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Space systems. Non-destructive testing. Automatic ultrasonic inspection method of graphite ingot for solid rocket motors

10.3403/30197003u ◽

2015 ◽

Keyword(s):

Ultrasonic Inspection ◽

Space Systems ◽

Non Destructive Testing ◽

Destructive Testing ◽

Inspection Method ◽

Solid Rocket Motors ◽

Rocket Motors ◽

Solid Rocket ◽

Non Destructive

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A Real-Time Approach To Detect Seal Defects in Food Packages Using Ultrasonic Imaging

Journal of Food Protection ◽

10.4315/0362-028x-64.9.1392 ◽

2001 ◽

Vol 64 (9) ◽

pp. 1392-1398 ◽

Cited By ~ 10

Author(s):

NEIL N. SHAH ◽

PAUL K. ROONEY ◽

AYHAN OZGULER ◽

SCOTT A. MORRIS ◽

WILLIAM D. O'BRIEN

Keyword(s):

Image Quality ◽

Ultrasonic Inspection ◽

Spatial Sampling ◽

Ultrasonic Frequency ◽

Ultrasound Images ◽

Inspection Method ◽

Raster Scanning ◽

Food Packages ◽

Inspection Systems ◽

Scanning Geometry

The microbial integrity of many types of flexible food packages depends on a zero defect level in the fused seam seal. Human inspection for defects in these seals is marginal at best, and secondary incubation protocols are often used to spot packages with compromised integrity before releasing product for sale. A new type of inspection method has been developed and is being evaluated for robustness. The purpose of the study was to evaluate a new raster scanning geometry to simulate continuous motion, online ultrasonic inspection of the seal region in flexible food package seals. A principal engineering tradeoff of scanning inspection systems is between increased line speed that results from decreased spatial sampling (less acquired data to process) and decreased image quality. The previously developed pulse-echo Backscattered Amplitude Integral (BAI) mode imaging technique is used to form ultrasound images using the new scanning geometry. At an ultrasonic frequency of 22.9 MHz, 38- and 50-μm-diameter air-filled channel defects in all-plastic transparent trilaminate are evaluated. The contrast-to-noise ratio (CNR) of the processed BAI-mode image is used to quantify image quality as a function of spatial sampling. Results show seal defects (38- and 50-μm diameter) are still detectable for undersampled conditions, although image quality degrades as spatial sampling decreases. Further, it is concluded that the raster scanning geometry is feasible for online inspection.

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Automatic Ultrasonic Inspection Method of Railway Axle and its Remaining Life Prediction

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.213.291 ◽

2011 ◽

Vol 213 ◽

pp. 291-296 ◽

Cited By ~ 2

Author(s):

Hong Wei Hu ◽

Xiong Bing Li ◽

Xiang Hong Wang ◽

Yi Min Shao

Keyword(s):

High Speed ◽

Fatigue Cracks ◽

Ultrasonic Inspection ◽

Inspection System ◽

Remaining Life ◽

High Speed Railway ◽

Inspection Method ◽

Spiral Trajectory ◽

Image Element ◽

The Matrix

With the high speed railway utilization, the probability of defects or fatigue cracks in railway axles is increased. An automatic ultrasonic inspection system for railway axles is presented. This system uses combined probes and inspects the defects with spiral trajectory along the axis of the axle. Through the matrix representation of C-scan image element, a defect edge extraction method is adopted, with which the defect parameters of crack are obtained automatically. Based on these defect parameters, the stress intensity factor is assessed by svm regression and the method to predict remaining life is proposed.

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Ultrasonic Inspection of Thin Duplex Steel Welds by Phased Array

Materials Science Forum ◽

10.4028/www.scientific.net/msf.818.256 ◽

2015 ◽

Vol 818 ◽

pp. 256-259

Author(s):

Erika Hodúlová ◽

Ingrid Kovaříková ◽

Beáta Šimeková ◽

Koloman Ulrich

Keyword(s):

Weld Joint ◽

Phased Array ◽

Ultrasonic Inspection ◽

Base Material ◽

Outer Diameter ◽

Experimental Sample ◽

Inspection Method ◽

Duplex Steel ◽

Steel Welds ◽

Weld Root

The non-destructive inspection of duplex steels is a big challenge, being composed of ferrite and austenite, have some particularities. When using ultrasound, for instance, its waves propagate well in ferrite, but suffer strong attenuation, scattering and refraction in austenite. The aim of this work is to use the Phased Array ultrasonic inspection method for the thin (4 mm) duplex steel weld joint inspection. The experimental sample was made of duplex steel shaped tube with an outer diameter of 44 mm and a wall thickness of 3.8 mm welded with a laser beam. The experiment was necessary to verify attenuation of duplex steel. On the base material and the weld joint were made the artificial defects, in which the adjusted sensitivity of the ultrasonic device was set.The result of the measuring was the defect echo coming from the weld root layer. The length (about 25 mm) can only be estimated due to the inaccurate constant velocity of probe motion along the surface.

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