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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. Introduction .

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auditor ndt training
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.
introduction
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.
agenda
Agenda
  • Training and Certification.
  • Audit/Evaluation & Surveillance.
  • Liquid Penetrant Inspection.
  • Magnetic Particle Inspection.
  • Radiography Inspection.
  • Ultrasonic Inspection.
  • Eddy Current Inspection.
overview
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.
overview5
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

training and certification
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.
training and certification7
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.

training and certification8
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.

training and certification9
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.

training and certification10
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

training and certification11
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)
training and certification12
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.
examination
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)
examination14
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)
examination15
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).
examination16
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)

training and certification17
Training and certification
  • The employer’s 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.

training and certification18
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)

training and certification19
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)

audit evaluation and surveillance
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?

audit evaluation and surveillance21
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?

audit evaluation and surveillance22
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?

audit evaluation and surveillance23
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?

audit evaluation and surveillance24
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

audit evaluation and surveillance25
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.?

audit evaluation and surveillance26
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?

liquid penetrant astm e1417
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
liquid penetrant
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
liquid penetrant29
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
liquid penetrant30
Liquid Penetrant
  • Solvent removers shall be of the following classes 1) Class 1- Halogenated 2) Class 2 –Nonhalogenated 3) Class 3 – Specific application
liquid penetrant31
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.
liquid penetrant32
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.
liquid penetrant33
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
liquid penetrant34
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.
liquid penetrant35
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.
liquid penetrant36
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.
liquid penetrant37
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.
liquid penetrant38
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.
liquid penetrant39
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)
liquid penetrant40
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
liquid penetrant41
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.
magnetic particle astm e1444
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.
magnetic particle
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.
magnetic particle44
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%.
magnetic particle45
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.
magnetic particle46
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.
magnetic particle47
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.
magnetic particle48
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.
magnetic particle49
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

radiography
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.
radiography51
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.
radiography52
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.
radiography53
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.
radiography54
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.
radiography55
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.
radiography56
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.
radiography57
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)
radiography58
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.

radiography59
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.

radiography60
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.
radiography61
Radiography
  • Storage of materials 1) Film should be stored in a cool dry place on it’s 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.
radiography62
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.
radiography63
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.
radiography64
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.
ultrasound
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.
ultrasound66
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.
ultrasound67
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
ultrasound68
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.
ultrasound69
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.
ultrasound70
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.

ultrasound71
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.
ultrasound72
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.
ultrasound73
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.
eddy current
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.
eddy current75
Eddy Current

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

eddy current76
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
eddy current77
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.
eddy current78
Eddy Current
  • Reference standards – should be of the same material chemical composition, heat treat, physical and mechanical properties as the part to be inspected.
eddy current79
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.
eddy current80
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

eddy current81
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.
eddy current82
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.
summary
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.
information
Information
  • Additional information on the subject of NDT can be purchased from the ASNT at asnt.org