AUDITOR%20NDT%20TRAINING

1
AUDITOR NDT TRAINING

• The purpose of this training is to give the
  auditor a familiarity of the quality control and
  quality assurance systems associated with
  Nondestructive testing.

2
Introduction

• The reference material used in this presentation
  is SNT-TC-1A, ASTM Standards 2000 edition,
  Nondestructive inspection evaluation checklist
  (from FAA sight).
• From this presentation you should be able to be
  able to understand and evaluate an NDT facilities
  quality systems.

3
Agenda

• Training and Certification.
• Audit/Evaluation Surveillance.
• Liquid Penetrant Inspection.
• Magnetic Particle Inspection.
• Radiography Inspection.
• Ultrasonic Inspection.
• Eddy Current Inspection.

4
Overview

• It is recognized that the effectiveness of
  nondestructive testing applications depends upon
  the capabilities of the personnel who are
  responsible for and perform it.
• As the auditor you will be required to evaluate
  NDT personnel and facilities to make a
  determination of compliance in accordance with
  the vendors manual, and required specifications.
• The five elements that can be used to evaluate
  any NDT organization from manufacturing to
  maintenance.

5
Overview

• 1) Documentation- written procedures,
  processes specifications and/or methods used by
  the vendor in performance and controls of NDT
  activities.
• 2) Organization- relationship of NDT
  organization to management.
• 3) Environment- the general physical
  condition of the facility, e.g.,housekeeping,
  storage, safety, consumable management,
  equipment.
• 4) Calibration- process by which an item is
  checked to a standard.
• 5) Training- methods used and records
  maintained to train and retrain NDT personnel

6
Training and Certification

• The requirements for training, qualification, and
  certification in each NDT method should be part
  of the vendors manual or written practice.
• Some recommended practices are ASN-TC-1A,
  ANSI/ASNTCP89 NAS 410 (previously Mil Std 410E),
  ATA105, ISO 9712.

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Training and certification

• Three basic Levels of qualification.
• 1) Level I- An NDT Level I individual should
  be qualified to properly perform specific
  calibrations, specific NDT, and specific
  evaluations for acceptance or rejection
  determinations according to written instructions
  and to record results.The NDT Level I should
  receive the necessary instruction or supervision
  from a certified Level II or III individual.

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Training and certification

• 2) Level II- An NDT Level II individual should
  be qualified to set up and calibrate equipment
  and to interpret and evaluate results with
  respect to applicable codes, standards and
  specifications.The Level II should be thoroughly
  familiar with the scope and limitations for
  methods for which qualified and should exercise
  assigned responsibilities for OJT training and
  guidance of trainees and Level I personnel.

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Training and certification

• 3) Level III- An NDT Level III individual
  should be capable of developing, qualifying, and
  approving procedures, establishing and approving
  techniques, interpreting codes, standards, and
  specifications and procedures and designating
  the particular NDT methods, techniques, and
  procedures used. The NDT Level III should be
  responsible for the NDT operations for which
  qualified and assigned and should be capable of
  interpreting and evaluating results in terms of
  existing codes, standards and specifications.

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Training and certification

• Level III continued- The NDT Level III should
  have sufficient practical background in
  applicable materials, fabrication and product
  technology to establish techniques and to assist
  in establishing acceptance criteria when none are
  otherwise available. The NDT Level III should
  have general familiarity with other appropriate
  NDT methods, as demonstrated by an ASNT Level III
  examination or other means. The NDT Level III ,
  in the methods in which certified, should be
  capable of training and examining NDT Level I and
  II personnel for certification in those methods

11
Training and certification

• Some procedure also may call out for a trainee, a
  trainee is not authorized to accomplish,
  interpret or report any inspection requirements.
• Some procedures may also call out for an NDT
  instructor an instructor is usually a Level II
  working under direction of the companies Level
  III.
• These Levels may also be subdivided into approval
  to comply with specific procedures such as
  conductivity, ultrasonic thickness measurement(
  should be in the vendors written practice)

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Training and certification

• The required amount of training required to
  qualify and certify the NDT inspector should be
  part of the vendors written practice.
• The requirements of each recommended practice
  vary on the amount of formal training and
  experience.
• Personnel should complete sufficient organized
  training to become thoroughly familiar with
  principles and practices of the specified NDT
  method.

13
Examination

• May be accomplished by an outside agency, but
  does not alleviate the employer of
  responsibility.
• For Level I and II a general, specific, and
  practical test is required.(ASNT)
• For Level III a basic, method, and specific test
  is required.(ASNT)

14
Examination

• The Level III shall be responsible for the
  administration and grading of examinations for
  Level I Level II or other Level III personnel.
• For Level I or II personnel the composite grade
  should be determined by averaging the results of
  the general, specific and practical exam.(ASNT)
• Note-ISO 9712 has a general and specific exam and
  each exam will have a written and a practical
  part
• For Level III personnel the composite grade
  should be determined by averaging the results of
  the basic (required only once), method, and
  specific exams.(ASNT)

15
Examination

• Minimum passing grade should consist of no
  individual test grade below 70 and the composite
  grade should be no less than 80 (ASNT).
• When an examination is administered and graded
  for an employer by an outside agency and the
  outside agency issues a pass or fail only, on a
  certified report the employer may accept the pass
  grade as a 80 for that particular examination
  (ASNT).

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Examination

• Also an eye exam should be accomplished
  annually for near vision acuity and every 3 years
  for color contrast Differentiation.
• Re-certification for Level I and II should be
  every 3years, Level III every 5 years.(ASNT)

17
Training and certification

• The employers certification shall be deemed
  revoked when employment is terminated.
• A Level I, II or III certification may be
  re-instated to the former NDT Level by a new
  employer based on examination, provided all the
  all these conditions have been met.
• 1) employee has proof of prior certification.
• 2) The employee was working in the capacity
  to which certified within 6 months of
  termination.
• 3)The employee is being re-certified within
  within 6 months of termination.

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Training and certification

• 4) Prior to being examined for certification,
  employees not meeting the above requirements
  should receive additional training as deemed
  appropriate by the Level III.(ASNT)

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Training and certification

• A Level I, II, or III whose certification has
  been terminated may be re-instated to the former
  NDT Level, without a new examination, provided
  all the following conditions have been met.
• 1) The employer has maintained the
  personnel certification records.
• 2) The employees certification did not
  expire during termination.
• 3) The employee is being re-instated within
  6 months of termination (ASNT)

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Audit / Evaluation and Surveillance

• Documentation
• 1) Does the facility have a manual to
  include an organizational chart?
• 2) Does the manual contain or refer to the
  appropriate specifications, are they current ,
  and available?
• 3) Are there provisions in the manual for
  internal review/evaluation and are the
  appropriate records maintained?

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Audit / Evaluation and Surveillance

• 5) Are there procedures in place to revise the
  manual?
• 6) Are there procedures in place for retention of
  records?
• 7) Does the manual contain procedures that
  address nonconformities?
• 8) Are the manuals and procedures available to
  and used by qualified personnel?
• 9) Does the manual contain controls for
  subcontracts for NDI services?
• 10) Does the manual contain controls for
  management of NDI products, materials, and
  consumables?

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Audit/Evaluation and Surveillance

• 11) Is there a separate NDI organization in the
  facility?
• 12) Does the NDI manager or equivalent have
  direct line authority to the NDI qualified
  personnel?
• 13) Are the NDI requirements provided to the NDI
  inspection personnel by use of written practice?
• 14) Does the NDI manager, or equivalent, review
  the quality assurance system to monitor
  compliance to the FAA approved data?
• 15) Are proper shift change procedures in place?

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Audit/Evaluation and Surveillance

• Environment
• 1) Is the size of the work area sufficient to
  perform the NDI inspections?
• 2) Is there adequate work area for storage and
  separation of NDI materials?
• 3) Is there a method for controlling and
  segregating nonconforming NDI equipment and
  materials?
• 4) Are appropriate manuals, procedures, and other
  documentation available for use by qualified
  personnel?

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Audit/Evaluation and Surveillance

• Environment (continued)
• 5) Are adequate parts handling systems (cranes,
  hoists, lifts etc) available?
• 6) Do routing documents specify the operation
  needed and in what sequence?
• 7) Is adequate protection provided to parts
  during handling and routing?
• 8) Is metal to metal contact of finished surfaces
  prevented during handling?
• 9) Are obsolete documents removed from inspection
  areas

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Audit / Evaluation and Surveillance

• Calibration
• 1) Is there a procedure for calibrating
  inspection devices to certified standards?
• 2) Are there procedures for segregation of
  functional and nonfunctional equipment?
• 3) Are procedures in place to ensure
  repaired equipment is recalibrated?
• 4) Are reference standards properly
  labeled, stored and used?
• 5) Are independent data available for
  reference standards, ie., drawings, metrology,
  etc.?

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Audit / Evaluation and Surveillance

• Calibration (continued)
• 6) Are the calibration methods documented?
• 7) Do calibration methods include environment
  controls, standards to be used, and accuracy
  requirements?
• 8) Are setup verifications performed on all
  shifts as appropriate?

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Liquid Penetrant (ASTM E1417)

• 2 Basic Types
  1) Type I
  Fluorescent 2) Type II
  Visible
• 4 Methods 1) Method A Water washable 2)
  Method B Post-emulsified, lipophilic 3) Method
  C Solvent-removable 4) Method D
  Post-emulsified, hydrophilic

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Liquid Penetrant

• Sensitivity Levels These levels are for Type I
  penetrants only. Type II penetrants have only a
  single sensitivity and is not represented by any
  level. 1) Sensitivity Level ½ - Very low 2)
  Sensitivity Level 1 Low 3) Sensitivity Level
  2 Medium 4) Sensitivity Level 3 High 5)
  Sensitivity Level 4 Ultrahigh

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Liquid Penetrant

• Developers shall be the following forms 1) Form
  a Dry powder 2) Form b Water-soluble 3)
  Form c Water-suspendable 4) Form d
  Nonaqueous for Type I fluorescent. 5) Form
  e Nonaqueous for Type II visible dye. 6)
  Form f Specific application

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Liquid Penetrant

• Solvent removers shall be of the following
  classes 1) Class 1- Halogenated 2)
  Class 2 Nonhalogenated 3) Class 3 Specific
  application

31
Liquid Penetrant

• Quality control and system performance. 1)
  Penetrant contamination Accomplished daily to
  determine if any of the following conditions are
  evident precipitates, waxy deposits, white
  coloration, separation of constituents, surface
  scum, or any other evidence of contamination or
  breakdown.

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Liquid Penetrant

• Developer contamination ( Aqueous soluble and
  suspendable) accomplished daily. 1)
  Checked for fluorescence, as appropriate, and
  coverage by immersing an aluminum panel. Failure
  to uniformly wet the panel or any observed
  fluorescence is unsatisfactory and the developer
  shall be replaced.

33
Liquid Penetrant

• Developer concentration Aqueous soluble and
  suspendable accomplished weekly.
  1) Checked with a hydrometer to supplier
  specification.
• Developer condition (Dry) accomplished daily.
  1) Check to
  see that the developer is fluffy and not caked
  also check for fluorescent specks 10 or more
  specks or any caking is unsatisfactory

34
Liquid Penetrant

• Water wash pressure checked each shift. 1)
  Should not exceed 40 psi, minimum distance 12
  inches from part. (need not be recorded)
• Water Temp. Checked each shift 50 to 100
  degrees F. Note If immersion rinse is
  being used the water should be agitated.

35
Liquid Penetrant

• Black Light intensity Checked daily. 1)
  Minimum 1000 micro watt/cm2 at 15 inches also
  check filter for damage.
• Inspection area cleanliness Checked daily (Need
  not be recorded)
• Water based penetrant water concentration
  Checked weekly. 1) Checked with a
  refractometer to MFG. Specifications.

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Liquid Penetrant

• Non-water based penetrant water content (Method
  A) Checked monthly. 1)Test method D95 or Karl
  Fischer method. 5 water content Max.
• Emulsifier concentration (hydrophilic) Checked
  weekly. 1) Checked with a refractometer to
  MFG specifications.

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Liquid Penetrant

• Penetrant sensitivity Checked weekly. 1) A
  comparison with unused sample if the sensitivity
  drops below unused material is unsatisfactory.
• Fluorescent brightness Checked
  quarterly. 1) Usually accomplished in a
  Lab. With a fluorometer or a photofluorometer
  must maintain 90 of original brightness.

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Liquid Penetrant

• Penetrant removability (Method A) Checked
  monthly. 1) Test shall by accomplished using
  normal wash parameters compare with unused
  material.
• Emulsifier removability Checked
  monthly. 1) Compare with unused material
  on test piece or production part.

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Liquid Penetrant

• Emulsifier water content (lipophilic) Checked
  monthly. 1) Test method D95 or Karl Fischer
  method usually sent to a Lab.
• Drying oven calibration Checked quarterly (may
  be reduced or extended when substantiated by
  performance)

40
Liquid Penetrant

• Light meter calibration Checked semiannually
  (may be reduced or extended when
  substantiated) 1) Both black light and
  visible light meters IAW MIL-STD-45662 or
  ANSI/NCSL Z540-1

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Liquid Penetrant

• Preparing and Precleaning All coatings and
  other conditions such as paint, plating,
  corrosion, scale, smeared metal, welding flux,
  chemical residues or any other material that
  could prevent from entering discontinuities,
  suppress dye performance, or produce unacceptable
  background.

42
Magnetic Particle(ASTM E1444)

• Magnetic particle inspections can be accomplished
  wet, dry, fluorescent, visible, utilizing AC or
  DC current induced magnetism in the circular,
  longitudinal direction, or multidirectional.
• FAR part 145.49 you must have equipment for wet
  and dry magnetic techniques, residual and
  continuous methods and portable for inspections
  of welds both on or off the aircraft.

43
Magnetic Particle

• Quality control and performance checks.
• Light intensity. Check daily 1) Black Light
  minimum intensity 1000 micro watt/cm2 also check
  filter for damage. 2) Visible Light
  minimum 100fc or 1000 lx. 3) Ambient Light
  2fc maximum.

44
Magnetic Particle

• System performance using a test piece or ring
  specimen. Check daily.
• Wet particle concentration. Check each shift
  Shall be .1 to .4ml in a 100ml sample fluorescent
  particles. Shall be 1.2ml to 2.4ml for
  nonfluorescent particles.
• Gauss meter (Teslameter) reading zero. Check each
  use.
• Gauss meter (Teslameter) accuracy. 6 months.
• Ammeter accuracy. Check 6 months usually
  accomplished with a shunt and a calibrated
  ammeter IAW MFG specifications -10.

45
Magnetic Particle

• Quick break check. Check 6 months - can use an
  oscilloscope or other method recommended by the
  MFG.
• Dead weight check. Check 6 months Yokes and
  permanent magnets (when allowed) 1) A.C.
  shall have a lifting force of at least 10lbs with
  a 2 to 4 inch spacing. 2) D.C. lifting force
  30lbs 2 to 4inch spacing, or 50lbs 4 to 6inch
  spacing.

46
Magnetic Particle

• Wet particle contamination. Check each shift/
  weekly. 1) Examine the the liquid above the
  precipitate with a black light. fluorescence
  should be comparable to original solution. 2)
  Examine the graduated portion of the tube both
  visible light and black light for striations or
  bands, different in color or appearance this may
  indicate contamination 30 maximum.

47
Magnetic Particle

• Water break test. Check daily Only on water
  based vehicle with a wetting agent. 1) Flood the
  part with conditioned water, and the appearance
  is noted after flooding is stopped. If film of
  suspension breaks, exposing bare surface,
  insufficient wetting agent is present or the part
  has not been cleaned properly.

48
Magnetic Particle

• Preparation of parts. 1) Demagnetize the
  part before examination if prior operations have
  produced a residual magnetic field. 2)The
  surface of the part to be inspected shall be
  smooth, clean, dry, and free of oil, scale,
  machining marks, or other contaminants or
  condition that might interfere with the
  efficiency of the inspection.

49
Magnetic Particle

• 3) No coating that may prevent detection of
  surface defects. Paint or chrome greater than
  .003 inch in thickness, and ferromagnetic coating
  such as electroplated nickel greater than .001
  inch

50
Radiography

• Safety and exposure requirements are regulated by
  the NRC and State agencies.
• Individual exposure should be maintained on
  record at the facility.
• Industrial radiation license is issued by the
  state and also thru the NRC for the use of a
  radioactive isotopes.
• CFR 10 Parts 19, 20, 21, 30, 34 and 70 apply to
  regulating and licensing for use of radioactive
  isotopes.

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Radiography

• CFR 10 Part 19 regulations establish the
  requirements for posting of notices, work
  instructions and reports by licensees to persons
  (employees) who participate in licensed
  activities and options available to employees in
  connection with NRC inspections of licensees.
  Part 19 establishes the right and
  responsibilities of individuals and the NRC on
  any matter within the commissions jurisdiction.

52
Radiography

• CFR 10 Part 20 establishes standards for
  protection against radiation hazards arising out
  of activity under licenses issued by the NRC.
  Part 20 discusses the concept of ALARA, and
  standards for dose limits for all persons who
  receive, possess, use or transfer material
  licensed under the NRC.

53
Radiography

• CFR 10 Part 21 establishes reporting procedures
  and requirements for any individual or
  responsible officer of a firm constructing,
  owning, operating or supplying components
  licensed or regulated by the NRC that fail to
  comply with or regulations relating to safety.
  Part 21 establishes time limits for reporting to
  the NRC when basic component defect or failure
  pose a substantial hazard.

54
Radiography

• CFR 10 Part 30 prescribes rules applicable to all
  persons in the United States governing domestic
  licensing of byproduct material under the Atomic
  Energy Act of 1954, as amended, and Title II of
  the Energy Reorganization Act of 1974.

55
Radiography

• CFR 10 Part 34 establishes requirements for the
  issuance of licenses for the use of sealed
  sources containing byproduct material and
  radiation requirements for persons using such
  sealed sources in radiography. Nothing in this
  part shall apply to uses of byproduct material
  for medical diagnosis or therapy.

56
Radiography

• Part 34 cont. Includes requirements for operating
  and emergency procedures, for training of
  radiography personnel, equipment performance,
  record maintenance, securing and storing
  radiographic exposure devices and personal
  audits.
• CFR 10 Part 70 requirements for packaging,
  preparation for shipment, and transportation of
  licensed material.

57
Radiography

• Radiation detection devices. 1) Survey Meter
  Measures dose rate. Gas filled tubes are used in
  the 2 types of survey meters the ionization
  chamber survey meter and the Geiger-Muller
  (or G-M) survey meter. The Ion chamber
  survey meter is primarily used. Survey meters
  should be calibrated every 6 months (CFR 10 Part
  34)

58
Radiography

• 2) Pocket Dosimeter The pocket dosimeter is
  basically an air- filled ion chamber.The pocket
  dosimeter uses a charger to apply an electric
  charge to zero the quartz fiber as the dosimeter
  is exposed to ionization radiation, the ions
  created will neutralize the charge on the fiber
  and wire causing the fiber to move toward the
  wire giving a reading of exposure in
  milliroentgen (mR). The pocket dosimeter should
  be calibrated every12 months.

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Radiography

• 3) Film Badge or TLD Must be sent out monthly
  to a certified Lab for reading, they will send
  back a report of individual exposure, which must
  become a part of the individual personal exposure
  record.
• 4) Rate Alarm Set to 500 mrem/hr. calibrate
  every 12 months, may only be required for use
  with isotopes.

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Radiography

• ALARA Is an acronym for as low as reasonably
  achievable which means make every effort to
  maintain radiation exposures as far below the
  dose limits as is practical.
• The radiation area shall maintained to a maximum
  of 2 millirems.

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Radiography

• Storage of materials 1) Film should be
  stored in a cool dry place on its end, the
  expiration date should be on the box. 2)
  Chemicals (starter, fixer, and developer) should
  be stored in an appropriate locker. Most of these
  chemicals have a 2 year life limit marked on the
  box.

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Radiography

• Radiation Safety Officer. 1) The RSO is the
  individual with the responsibility for overall
  radiation safety program and who meets the
  requirements. 2) The RSO shall ensure that
  radiation safety activities are being performed
  in accordance with approved procedures and
  regulatory requirements in the daily operation of
  the licensees program. 3) The RSO shall
  establish and oversee all operating, emergency,
  and ALARA procedure.

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Radiography

• RSO cont. 4) Overseeing and approving all
  phases of the training program for radiographic
  personnel. 5) Ensure that the required radiation
  surveys and leak tests are performed and
  documented in accordance with regulations. 6)
  Ensure that personal monitoring devices are
  calibrated and used properly. 7)Ensuring that
  operations are conducted safely and to assume
  control for instituting corrective
  actions.

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Radiography

• Radiographer should have had not only the
  required amount of radiography training, but
  should have also had training in radiation
  safety. If the individual is using radioactive
  isotopes must meet the requirements of CFR10 Part
  34.
• Radiographer Assistant Should have training in
  radiation safety and if using an isotope must
  meet the requirements of CFR 10 Part 34.

65
Ultrasound

• Ultrasonic testing is the process of applying
  ultrasonic sound (above 20,000Hz) to a specimen
  and determining its soundness, thickness or some
  physical property.
• Ultrasonic pulse echo instrument generates high
  voltage electrical pulse of short duration. These
  pulses are applied to the transducer which
  converts them into mechanical vibrations that are
  applied to the material.

66
Ultrasound

• Ultrasonic through transmission Requires 2
  transducers one for sending and the other for
  receiving. Short or continuous waves are
  transmitted into the material.The quality of the
  material being tested is measured in terms of
  energy lost by the sound beam as it travels
  through the material.

67
Ultrasound

• Contact testing Where the transducer is coupled
  to the material through a thin layer of couplant.
• Immersion testing Both the material and the
  transducer are immersed in a tank of couplant
  (usually water).
• Couplant The primary purpose of a couplant is
  to provide a suitable path between the transducer
  and the test surface
• NOTE Do not use glycerin as a couplant on
  aluminum may cause corrosion

68
Ultrasound

• Longitudinal wave Have particle vibrations in a
  back and forth motion in the direction of
  propagation.
• Shear waves Have particle vibrations
  perpendicular to the direction of wave motion.
  Shear waves will not travel through liquid or
  gas.
• Surface waves Are elastic vibrations whose
  energy is confined to a narrow region just below
  the surface.

69
Ultrasound

• Displaying ultrasonic indications Three basic
  types A-scan, B-scan, C-scan. A-scan is a time
  versus amplitude display which reveals a
  discontinuity using a pip on a CRT. The A scan is
  read from left to right. B-scan typically
  uses an oscilloscope type screen to display a
  cross sectional view of the material being tested.

70
Ultrasound

• C-scan Is a Plan View presentation similar
  to an X-ray picture.The C-scan shows shape and
  location of the discontinuity but does not show
  depth.

71
Ultrasound

• Calibration standards Such as the IIW block,
  Miniature calibration block, Area amplitude
  blocks, DSC blocks and Distance amplitude
  blocks.Calibration standards are used for
  adjustments for simple ultrasonic testing
  procedures and to check on the reproducibility of
  measurement.

72
Ultrasound

• Reference standards Aid in calibrating the
  instrument and indicating whether the
  discontinuities expected will be detected by
  preselected sensitivity. The standards apart from
  facilitating initial adjustment of the
  instrument, also check on reproducibility of the
  measurement.
• Reference standard material should be identical
  to the object being tested in chemical
  composition, heat treat, physical and mechanical
  characteristics.

73
Ultrasound

• Facility being evaluated should have the
  appropriate standards, transducers, equipment,
  technical data.
• To prepare a part for ultrasonic inspection the
  part should be free of loose paint, dirt, and
  scale.

74
Eddy Current

• Eddy current testing is a non-destructive test
  technique based on inducing electrical currents
  in the material being inspected and observing the
  interaction between those currents and the
  material.
• Eddy Current can be used for crack detection,
  conductivity measurement, nonconductive coating
  thickness, material loss due to corrosion
• Indicating devices An important part of the
  eddy current test system is the part of the
  instrument that gives the technician of the
  change in impedance. As usual there are several
  different types of devices used.

75
Eddy Current

• 1) Analog meter 2) Digital
  meter 3) Oscilloscope 4) Impedance
  plane 5) Strip chart recorders

76
Eddy Current

• Eddy Current Coils and Probes Inspection coils
  can have a variety of forms and can be arranged
  in a variety of ways. The choices of the type of
  arrangement of the inspection coil depends on the
  test situation. 1) Single coil
  absolute 2) double coil absolute 3)
  Differential coil arrangement 4)
  Reflection coil arrangement

77
Eddy Current

• The previous coil arrangements can be installed
  on a variety of probe configurations such as. 1)
  Surface probes 2) Holes probes 3)
  Encircling 4) Internal (bobbin)
• Erroneous indications can come from nonspecific
  variations in the test object such as coating
  thickness changes, conductivity changes, even
  electrical interference.

78
Eddy Current

• Reference standards should be of the same
  material chemical composition, heat treat,
  physical and mechanical properties as the part to
  be inspected.

79
Eddy Current

• Conductivity measurements Conductivity
  measuring can be used to determine a materials
  temper if you know the alloy, it can be used to
  sort different alloys, it can also be used to
  determine heat damage on aluminum alloys.
  Conductivity measurement alone can not be used to
  identify different alloys due to the overlap of
  conductivity ranges.

80
Eddy Current

• Conductivity cont. Accomplishing a conductivity
  measurement is achieved by using a conductivity
  instrument setting it up with known calibration
  standards of known value. A reading is given in
  IACS (International Annealed Copper Standard)
  These standards should be checked periodically
  for accuracy due some materials conductivity
  changes with age

81
Eddy Current

• Conductivity cont. Another way is to make a
  conductivity curve with an impedance plane
  instrument utilizing the calibration standard.
• Surface and subsurface defects can be discovered
  using eddy current by using different probe and
  coil configurations. As a rule the lower the
  frequency used the larger the depth of
  penetration.

82
Eddy Current

• As with any other NDT method the facility must
  have the appropriate equipment, probes,
  standards, technical data and trained personnel
  to perform the work.

83
Summary

• In this class we have covered training and
  certification, audit and evaluation and 5 of the
  most commonly used NDT methods in general terms.
  
• Read the vendors written practice, and look at
  the specifications in which inspections are to be
  accomplished Ensure that they have the required
  materials to accomplish the work. While using the
  1A standard and a little familiarity with NDT a
  thorough audit will be accomplished.

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Information

• Additional information on the subject of NDT can
  be purchased from the ASNT at asnt.org