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Composite materials are being used more and more each year, especially in the aircraft industry. As a result there is an increase in the demand for nondestructive testing equipment designed for the inspection of parts made of
composite material. Aircraft manufacturers, maintenance service providers, and airline operators alike are looking for nondestructive equipment that will ensure the quality of their products and safety for their customers.
Parts made of composite materials pose an inspection challenge because they come in many shapes and thicknesses. Inspection problems caused by the composite characteristics have been resolved with the use of R/D Tech's
OmniScan™ PA. Combined with phased array probes and the water box, the OmniScan PA provides an efficient and versatile nondestructive test solution.
The OmniScan PA uses a water delay line and a linear array composed of 64 to 128 elements firing in sequence to cover a large area in a single pass. Furthermore, the unit provides an amplitude or time-of-flight C-scan mapping
view that makes data analysis an easy task. The main advantages of using the OmniScan PA with this technique are the increased inspection speed due to the large coverage of the phased array probe and the portability of the
complete equipment.
Typical Inspection Requirements
• Portable inspection equipment
• Composite parts with thicknesses ranging from 3 to 100 mm
• Flat parts or parts with T joints
• Probe with delay line that adjusts to surfaces with different shapes and radiuses
• Encoded axis for flaw sizing
Types of Defects
• Delamination
• Disbonding
• Porosity
Description of the Solution
• Manual inspection with phased-array probe and water box with encoder
• Linear scans at 25 mm to 50 mm/s
• Electronic scanning with 64 to 128 elements covering a width of 30 mm to 95 mm
• Real-time display of amplitude or time-of-flight C-scans using echo-to-echo measurements with up to three gates
• Storage of amplitude and time-of-flight C-scans for analysis
Advantages of the Solution
• Enhanced data imaging reduces human-error factor.
• Large multielement probe increases inspection speed.
• Resolution improvement without raster scanning.
• Storage of A-scan and C-scan data allows further analysis or periodic comparison.
Equipment Required
• OmniScan PA acquisition unit 16:128 linear package
• 1- to 5-MHz probe with 64 or 128 elements
• Water box with one axis encoder
• Couplant
Inspection Method
The probe is placed in the water box. A zero-degree electronic scan is performed through successive firing of the elements. The gates are set to measure real thickness from the interface echo to the back wall. A sensitivity
calibration is performed to provide the same signal amplitude from each beam of the electronic scan.
A linear scan is performed and the OmniScan displays, in real time, an amplitude or time-of-flight C-scan. At the end of the scan, the analysis and the report can be made directly on the OmniScan unit, or the inspection can be
saved and downloaded to a computer to be analyzed at a later time.
The use of phased-array probes can eliminate one axis of a two-axis surface scan.
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