Radiographic Testing (RT)

Radiographic Testing involves the use of penetrating X or Gamma radiation to examine parts and products for imperfections. An X – ray machine or radioactive isotope is used as a source of radiation. Radiation is directed through a part onto the film. When the film is developed, a shadowgraph is obtained that shows the internal soundness of the part. *Indicates the minimum days of classes.

• View Syllabus

  1.0 Introduction

  1.1 History and discovery of radioactive materials
  1.2 Definition of Industrial radiography
  1.3 Need for radiation protection
  1.4 Review of school maths
  1.5 Responsibilities of levels of certification

  2.0 Fundamental properties of matter

  2.1 Elements and atoms
  2.2 Molecules and compounds
  2.3 Atomic particles
  2.4 Atomic structure
  2.5 Atomic number and weight
  2.6 Isotope Vs Radioisotope

  3.0 Radioactive materials

  3.1 Production
  3.2 Stable Vs Unstable
  3.3 Curie
  3.4 Half life of radioactive materials
  3.5 Plotting of radioactive decay
  3.6 Specific activity

  4.0 Types of radiation

  4.1 Particulate radiation
  4.2 Electromagnetic radiation
  4.3 X ray production
  4.4 Gamma ray production
  4.5 Gamma ray energy
  4.6 Energy characteristics of common radioisotopes
  4.7 Energy characteristics of X ray machine

  5.0 Interaction of radiation with matter

  5.1 Ionization
  5.2 Radiation interaction with matter
  5.3 Unit of exposure – the roentgen
  5.4 Emissivity of sources
  5.5 Emissivity of X ray devices
  5.6 Attenuation of radiation, shielding
  5.7 Half value layers
  5.8 Inverse square law

  6.0 Biological effects of radiation

  6.1 Natural, background radiation
  6.2 Unit of radiation dose
  6.3 Radiation, contamination
  6.4 Exposure limits and the banking concept
  6.5 Theory of allowable dose
  6.6 Radiation damage
  6.7 Symptoms of radiation injury
  6.8 Acute radiation exposure and somatic injury
  6.9 Personnel monitoring for tracking exposure
  6.10 Organ radiosensitivity

  7.0 Radiation detection

  7.1 Pocket dosimeter
  7.2 Difference between dose and dose rate
  7.3 Survey instruments
  7.3 Geiger – Muller tube
  7.4 Ionization chambers
  7.5 Scintillation chambers, counters
  7.6 Film badge
  7.7 TLDs
  7.8 Calibration

  8.0 Exposure devices and radiation sources

  8.1 Sealed source design and fabrication
  8.2 Gamma ray sources
  8.3 Beta and bremsstrahlung sources
  8.4 Neutron sources
  8.5 Exposure device characteristics
  8.6 Generator – high voltage rectifiers
  8.7 X ray tube design and fabrication
  8.8 X ray control circuits
  8.9 Accelerating potential
  8.10 Target material and configuration
  8.11 Heat dissipation
  8.12 Duty cycle
  8.13 beam filtration

  9.0 Principles of Flash radiography, Stereo radiography, In-motion radiography, Autoradiography

  10.0 Radiographic technique

  10.1 Process of radiography
  10.2 Penetrating ability or quality of X rays and gamma rays
  10.3 Spectrum of X ray tube source
  10.4 Spectrum of gamma radioisotope source
  10.4 X ray tube – change of mA or kVp effectquality and intensity

  11.0 Geometric exposure principles

  11.1 Shadow formation and distortion
  11.2 Shadow enlargement calculation
  11.3 Shadow sharpness
  11.4 Geometric unsharpness
  11.5 Finding discontinuity depth

  12.0 Radiographic screens

  12.1 Lead intensifying screens
  12.2 Fluorescent intensifying screens
  12.3 Intensifying factors
  12.4 Importance of screen to film contact
  12.5 Importance of screen cleanliness and care
  12.6 Techniques for cleaning screens
  12.7 Radiographic cassettes
  12.8 Composition of Industrial radiographic film
  12.9 The heel effect with X ray tubes

  13. Raidographs

  13.1 Formation of the latent image on film
  13.2 Inherent unsharpness
  13.3 Arithmetic of radiographic exposure
  13.4 milliamperage
  13.5 Reciprocity law
  13.6 Photographic density
  13.7 X ray exposure charts – material thickness, kV and exposure
  13.8 Gamma ray exposure chart
  13.9 Inverse square law considerations
  13.10 Calculation of exposure time for gamma ray and X ray sources
  13.11 Characteristic Hurter and Driffield curve
  13.12 Film speed and class descriptions
  13.13 Selection of film for particular purpose

  14.0 Radiographic image quality

  14.1 Radiographic Sensitivity
  14.2 Radiographic Contrast
  14.3 Film contrast
  14.4 Subject contrast
  14.5 Definition
  14.6 Film graininess and screen mottle effects
  14.7 Penetrameters or image quality indicators

  15.0 Film handling, loading and Processing

  15.1 Safe light and darkroom practices
  15.2 Loading bench and cleanliness
  15.3 Opening of film boxes and packets
  15.4 Loading of film and sealing cassettes
  15.5 Handling techniques for green film
  15.6 Elements of manual film processing

  16.0 Exposure techniques

  16.1 Single wall radiography
  16.2 Double wall radiography
  16.3 Viewing two walls simultaneously
  16.4 Offset double wall exposure single wall viewing
  16.5 Elliptical techniques
  16.6 Panoramic radiography
  16.7 Use of multiple film loading
  16.8 Specimen configuration

  17.0 Darkroom facilities, techniques and processing

  17.1 Facilities and equipment
  17.2 Automatic film processor Vs manual processing
  17.3 Safe lights
  17.4 Viewer lights
  17.5 Miscellaneous equipment
  17.6 Cassette loading techniques for sheet and roll
  17.7 Protection of radiographic film in storage
  17.8 Processing of film – manual
  17.9 Developer and replenishment
  17.10 Stop bath
  17.11 Fixer and replenishment
  17.12 Washing
  17.13 Prevention of water spots
  17.14 Drying

  18.0 Automatic film processing

  19.0 Film filing and storage

  19.1 Retention – life measurements
  19.2 Long term storage
  19.3 Filing and separation techniques

  20.0 Film digitization techniques
  
  21.0 Unsatisfactory radiographs – causes and cures

  21.1 High film density
  21.2 Insufficient film density
  21.3 High contrast
  21.4 Low contrast
  21.5 Poor definition
  21.6 Fog
  21.7 Light leaks
  21.8 Artifacts

  22.0 Film density

  22.1 Step wedge comparison film
  22.2 Densitometers
  22.3 Calibration and use of above equipments

  23.0 Practical use of X ray and Gamma ray equipments

  24.0 Radiological safety principles review

  24.1 Controlling personnel exposure
  24.2 Time, distance, shielding concepts
  24.3 ALARA
  24.4 Radiation detection equipment
  24.5 Exposure device operating characteristics

  25.0 Indications, discontinuities and defects

  25.1 Indications
  25.2 Discontinuities
  25.3 Inherent
  25.4 Processing
  25.4 Service

  26.0 Manufacturing processes and associated discontinuities

  26.1 Casting processes and associated discontinuities
  26.2 Ingots, blooms and billets
  26.3 Sand casting
  26.4 Centrifugal casting
  26.5 Investment casting

  27.0 Wrought processes and associated discontinuities

  27.1 Forgings
  27.2 Rolled products
  27.3 Extruded products

  28.0 Welding processes and associated discontinuities

  28.1 SAW
  28.2 SMAW
  28.3 GMAW
  28.4 FCAW
  28.5 GTAW
  28.6 Resistance welding
  28.7 Special welding processes – Electron beam, electroslag etc.

  29.0 Introduction to Codes, Standards, Specifications and Procedures

  29.1 Discussion on ASTM E 94 / E 142
  29.2 Question answer session on above codes
  29.3 Interpretation / Evaluation
  29.4 Materials processing as it affects use of item and test results
  29.5 Discontinuities, their causes and effects
  29.6 Radiographic appearance of discontinuities
  29.7 Nonrelevant indications
  29.8 Film artifacts

  30.0 Acceptance criteria

  NDTTech recommended training time for Level I / II – 80 Hours ( 10 Days)
  Recommended training references: (1) ASNT Hand book on RT (2) Nondestructive Testing hand book, Robert Mc Master (3) SNT TC 1A The above could be considered the minimum delivery topics. Participants are expected to learn and answer questions from these topics in the Level I / Level II examination.