2. • Film disappearing and becoming more expensive
• Greater latitude than film
• Eliminates environmental concerns over chemicals
• Fast results
• Easier to automate
• Ability to focus on one area (zoom in)
• Ability to adjust the contrast levels
Why Digital Radiography?
3. • Lower resolution – up to 20 lp/mm for film compared to 5 lp/mm for
IH systems
• Resolution (as most people know it) is dependent upon many factors
with a DR panel:
-Pixel Size -Signal to Noise
-Frame Averaging -Monitor Quality
• Detectors are expensive
• Sensitive to scatter radiation
• Systems need qualification requirements
• Operators need training
• Specs and standards non-existent / inadequate
• Crack detection
– Crack size needs to be quantified
Why Not Digital Radiography?
4. Concerns of Digital Radiography
• Probability of detection (detectability)
–What is the probability that a defect will be detected in a
part?
•Is the standard penetrameter really appropriate
for DR techniques, are phantoms needed?
•Exposure adequacy
–How does the pixel value (exposure)
relate to film density to ensure that the
defect will be detected?
5. • Verification Plan developed internally due to lack / inadequacy of
DOD or commercial specification
• Bldg 1913 System qualified in February 2008
• Bldg 286 System qualified in July 2008
• Same process can be used for re-qualification if equipment is
upgraded or additional systems are installed.
• Qualification is based upon ability to see defects.
• Alternate process will be needed to qualify equipment for cracks in
pressed delay columns and propellant grains.
System Qualification
6. System Information
• 2 Cabinet X-Ray System in CAD/PAD Manufacturing Buildings
– Sealed cabinet systems in buildings 1913 & 286
– Varian 320kV Source, Vertical Beam
– Thales Flashscan 33 127um (0.005” pixel size)
– 14-bit Detector (16,384 shades of gray)
– 4-axis manipulator, manual or computer controlled in building 1913
– 5-axis manipulator, manual or computer controlled in building 286
8. • Technique approved for fully assembled cutters based upon prior inspection
of the knife – delay assemblies with film
• Inspection of 2 lots completed to date with new digital Radiographic
Acceptance Criteria (RAC)
• Digital x-ray was able to identify damaged firing pin tips that were very
difficult to recognize on film.
• The system was critical in screening a multitude of units recalled from the
fleet.
M21 Program Transition
Original
Enhanced
9. • Technique approved in February 2008.
• Completed inspection of 2 lots to date.
• Propellant easily identified with digital
radiography using the adjustments
available.
• Use of a Radiographic Quality Indicator
(RQI) instead of penetrameter.
JAU-8 Program Transition
Original Enhanced
10. • M91 technique approved in July of 2008.
• Inspected a production lot.
• Digital identified the presence of material that was
difficult to see with film.
M91 Cartridge Transition
M91 Unit Close up of material
11. • Holding fixture completed for vertical x-ray of units.
• Technique was approved 12/01/08.
CCU-22 Impulse Cartridges
Close up of Head
Body
12. Additional Units
• Request from NASA for digital x-ray of an electronic package assembly
for SEAWAR.
• Assisting PAX river with digital x-ray of inertial reels
13. Computed Radiography (CR)
• Indian Head has a 100 micron Fuji CR System now, primarily used for
special projects
• Currently a 50 micron system has been awarded through CIP, and
delivered. Have yet to evaluate capabilities of the system
• Will need to stand up and qualify the current 100 micron CR system as
well as the 50 micron system.
• Potential for significantly better spatial resolution but benefits may not be
realized due to signal/noise ratio
• CR being used by several CAD/PAD vendors, primarily Fuji systems.
• Once capabilities have been determined, programs will need to be
identified for the transition.
14. Digital vs. Computed Radiography
• Digital Radiography
– Pros
• Faster Results
• Easier to automate
• Sharper edges
– Cons
• Lower resolution
• More expensive upfront
• Detectors are costly and
can be damaged
• High Energy is risky
• Computed Radiography
– Pros
• Cheaper up front
• Less risk with High Energy
• Higher resolution
• Integrates easier into film
process
– Cons
• Still requires processing
15. • Indian Head employees participating in Federal Working
Group for Industrial Digital Radiography (FWG-IDR)
• IH Level III head of System Qualification Team
• Attending yearly Digital Radiography Conference
• “Qualification Requirements for the Radiographic
Inspection of CAD/PAD Devices using Digital
Radiography and Computed Radiography” document is
currently in routing for signature. Used to qualify vendor
systems.
Advancement at Indian Head
