Dye Penetrate Test

The British Institute of Non-Destructive Testing is an accredited certification body offering personnel and quality management systems assessment and certification against criteria set out in international and European standards through the PCN Certification Scheme.

Certification Services Division 1 Spencer Parade, Northampton NN1 5AA, United Kingdom

Tel: +44(0)1604-259-056. Fax: +44(0)1604-231-489. E-mail: [email protected]

PCN/GEN Appendix E2 Issue 5 rev A

Further information concerning the content of PCN documents is available from the PCN Scheme Manager at the above address.

SPECIFIC REQUIREMENTS FOR THE CERTIFICATION OF PERSONNEL IN LIQUID PENETRANT TESTING FOR THE PRE & IN-SERVICE INSPECTION SECTOR

ASSOCIATED DOCUMENTS:

Appendix E2.2 to PCN/GEN

Examination Syllabus for the Certification of Personnel in Liquid Penetrant Testing of General Engineering Materials, Components and Fabrications.


Specimen Examination Questions for the Certification of Personnel engaged in Liquid Penetrant Testing of General Engineering Materials, Components and Fabrications.

CONTENTS

1. SCOPE ......................................................................................................................................... 2 2. EXAMINATION CONTENT ........................................................................................................... 2 3. CERTIFICATION AVAILABLE....................................................................................................... 3 4. RENEWAL AND RECERTIFICATION........................................................................................... 4 5. SUPPLEMENTARY EXAMINATIONS........................................................................................... 4 6. GRADING ..................................................................................................................................... 4

PCN/GEN Appendix E2 2 of 4 dated 1st January 2007

1. SCOPE

This document prescribes the specific requirements and procedures by which personnel may be examined and, if successful, certificated for the Liquid Penetrant testing of General Engineering Materials and Components. Requirements contained in this document are supplementary to those contained in the current edition of PCN General Requirements for Qualification and Certification of NDT Personnel.

2. EXAMINATION CONTENT

The examination format is described in PCN General Requirements. This Appendix amplifies the provisions of that document only where necessary.

2.1 Level 1

Except where exemptions apply (refer to PCN General Requirements), all candidates will be required to attempt an examination comprised of the following parts:

2.1.1 General theory of the Liquid Penetrant NDT method. Thirty multiple choice questions to be answered in 45 minutes. Minimum pass mark 70%.

2.1.2 Sector Specific Theory of the application of the Liquid Penetrant NDT method to general engineering products. Thirty multiple choice questions to be answered in 45 minutes. Minimum pass mark 70%.

2.1.3 Sector Specific Practical examination comprising:

(i) preparation of testing systems for use (this may involve system sensitivity and control checks).

(ii) testing three samples (selected by the examiner) in accordance with NDT instructions provided.

(iii) reporting test results in a prescribed manner on proforma report sheets.

The total time allowed for the practical examination is three hours. The minimum pass mark for the practical part is 70% per sample tested (failure to detect and report a reportable discontinuity in any one sample will result in failure of this examination part) and 70% overall.

2.2 Level 2


2.2.1 General Theory of the Liquid Penetrant NDT method. Thirty multiple choice questions to be answered in 45 minutes. The minimum pass mark is 70%.

2.2.2 Sector Specific Theory of the application of the Liquid Penetrant NDT method to the testing of general engineering products. Thirty multiple choice questions (ten of which will cover the basic casting, forging and welding processes and associated defects) to be answered in 45 minutes. The minimum pass mark is 70%.

2.2.3 Sector Specific Practical examination comprising:

(i) preparation of testing systems for use (this may involve system sensitivity and control checks).

(ii) testing three samples (selected by the examiner from castings, welds and wrought products, according to the certification sought - see Clause 3.2), in accordance with NDT procedures or instructions (two to be provided by the test centre and one to be generated by the candidate – see (iv) below) which will give, where appropriate, sensitivity levels and reporting thresholds.

(iii) reporting the results on the forms provided. Each test report must indicate the location type and size of any flaws detected.

(iv) preparation of a detailed NDT instruction (suitable for level 1 personnel to follow) for the testing of one of the above samples to a provided procedure, code, standard or specification, and prove the instruction by application.


The total time allowed for the sector specific practical examination is four hours. The minimum pass mark for the practical part is 70% per sample tested, 70% for the NDT instruction (failure to detect and report a reportable discontinuity in any one sample, or failure to produce an acceptable NDT instruction, will result in failure of this examination part) and 70% overall.

2.3 Level 3


2.3.1 A Basic Examination (information on the time allowed and pass mark is given in the current edition of PCN General Requirements), comprising:

A1) Thirty multiple choice questions covering materials technology and science, including typical defects in a range of products including castings, welds and wrought products.

A2) Ten multiple choice questions on the content of the current edition of PCN General Requirements for Certification of Personnel engaged in the application of non-destructive testing (a copy of which will be provided for use in the examination).

B) Sixty level 2 multiple choice questions on the general theory of four NDT methods. The examination will include fifteen questions on the NDT method in which the candidate is presently seeking certification, and a further fifteen on each of three other methods selected by the candidate (N.B. at least one of the four methods examined must be a volumetric method).

2.3.2 A Main Method examination comprising:

C1) Thirty multiple choice questions covering the general theory of the Liquid Penetrant NDT method.

C2) Twenty multiple choice questions covering the specific theory of Liquid Penetrant testing.

C3) The candidate will be required to produce a comprehensive test procedure embodying an NDT instruction for a specific general engineering product, to a provided specification, standard or code.

2.3.3 Level 3 candidates who do not hold PCN level 2 certification for the Liquid Penetrant testing of general engineering products (multi-sector) are required to successfully complete the examination described in Clause 2.2.3 except clause (iv).

3. CERTIFICATION AVAILABLE

3.1 Level 1 Liquid Penetrant Testing of General Engineering Materials, Components and Fabrications (multi-sector).


Alternatively, level 2 candidates may apply for single sector certification covering one or more of the following groups:

3.2.1 Castings

3.2.2 Welds

3.2.3 Wrought Products



4. RENEWAL AND RECERTIFICATION

4.1 The general rules for level 1 and level 2 renewal and recertification are fully described in PCN document CP16, and the rules for level 3 recertification are detailed in PCN document CP17.

4.2 Level 1 certificate holders seeking recertification will be required to undertake the practical examination detailed at Clause 2.1.3 above. The minimum pass mark for recertification is 80%.

4.3 Level 2 certificate holders seeking recertification will be required to undertake the practical examination detailed at Clause 2.2.3 above. The minimum pass mark for recertification is 80%.

5. SUPPLEMENTARY EXAMINATIONS

Existing PCN level 2 certificate holders who apply to be certificated for the Liquid Penetrant testing of additional products, will be required to pass a further practical examination comprising the testing of two samples from the group in which certification is sought (see Clause 3.2 above). Alternatively, candidates holding certification in one product category who apply for certification in the multi-sector (all product categories) will be required to pass a further practical examination comprising the testing of three samples selected by the examiner as representative of the additional categories sought (see Clause 3.2 above). Level two candidates attempting supplementary examination will not be required to produce a written instruction (Clause 2.2.3 (iv)).

6. GRADING

The method for composite grading of initial examinations, and the grading of supplementary examinations is specified in the current edition of PCN General Requirements.




PCN/GEN Appendix E2.2 Issue 5


SYLLABUS FOR THE EXAMINATION OF PERSONNEL IN LIQUID PENETRANT TESTING FOR THE PRE & IN-SERVICE INSPECTION SECTOR



Specific Requirements for the certification of Personnel in Liquid Penetrant Testing of General Engineering Materials, Components and Fabrications.


Specimen Examination Questions for the Certification of Personnel engaged in Liquid Penetrant Testing of General Engineering Materials, Components and Fabrications.

CONTENTS

LEVEL 1 SYLLABUS ........................................................................................................................ 2 LEVEL 2 SYLLABUS ........................................................................................................................ 3 LEVEL 3 SYLLABUS ........................................................................................................................ 5 REFERENCE LITERATURE............................................................................................................. 7


LEVEL 1 SYLLABUS 1. General Theory

1.1 Principles of Penetrant Inspection

1.1.1Basic principles of liquid penetrant testing: surface tension, viscosity, volatility, capillary action and their relevance to penetrating fluids.

1.1.2 Properties and requirements of emulsifiers, spirit remover and of a developer. Terminology associated with penetrant flaw detection.

1.2 Equipment and Materials

1.2.1 Penetrant: colour contrast, fluorescent, combined colour contrast and fluorescent.

1.2.2 Penetrant removers: solvents in liquid form, water only, water soluble, oil soluble emulsifiers.

1.2.3 Developers: dry powders, aqueous suspensions, aqueous solutions , non-aqueous developers.

1.2.4 Fixed installations, portable inspection kits and auxiliary equipment.

1.3 Methods of Assessing Sensitivity and Control Testing

Chromium plated and aluminium test blocks, defective components. Colour, fluorescent intensity and comparator checks of penetrants. Efficiency of penetrant removers. Fluorescence, coverage and concentration checks on developers.

2. Sector Specific Theory

2.1 Preparation for Testing

Surface preparation, cleaning methods, effect of surface finish and contaminants. Compatibility of materials.

2.2 Testing Technique

2.2.1Selection of appropriate technique.

2.2.2Method of application of penetrant, significance of temperature, drainage and self-drying, removal of excess penetrant, contact time.

2.2.3 Penetrant removal: liquid solvents, aqueous washes, post emulsifiers, contact times.

2.2.4 Drying of components. Application of developers; dry powders, liquid developers (aqueous and non-aqueous).

2.2.5 Viewing conditions: white light and UV(A) radiation and their assessment.

2.2.6 Types of discontinuity and their identification, false indications and their cause.

2.2.7 Preservation of indications: transparent tape transfer and other coating transfers, photographic (fluorescent and colour contrast).

2.3 Post Test Procedures Cleaning

2.4 Safety Precautions

Fire hazards, electrical safety, ventilation, toxic materials and safe use of UV(A) radiation.

2.5 Standards, codes and specifications

See essential reading list.

3. Sector Specific Practical

Refer to PCN/GEN Appendix E2.1.


LEVEL 2 SYLLABUS

4. General Theory

The level 2 candidate will be examined on the syllabus for level 1 but the examination questions will be more complex.


As level 1, but in addition:

5.1 Testing Procedures

Selection of the Penetrant and Developer for optimum sensitivity with due regard to inspection criteria, surface condition and ambient light levels.

5.2 Detectability of Defects

Advantages and limitations of the test method with regard to defect detection.

5.3 Interpretation and Reporting

Types of discontinuity and their identification. False indications and their cause. Preservation of indications: Lacquer developers, photographic (fluorescent and colour contrast).

5.4 Post Test Procedures

Post test cleaning and the need for restoration of preservation coatings.

6. Product Technology Theory

Product technology is only applicable to level 2 and level 3 candidates. The depth of knowledge required for this examination is given in the following syllabus but, briefly, the examination will cover:

• an understanding of the basic production process; • the terms used in the production process; • the terms, origin and nature of flaws related to the production process.

6.1 Basic Production - Crude and Finished Products

6.1.1 Ingot types narrow end up and wide end up, concast methods (continuous casting process). Definition used in the production of ingots and casting.

6.1.2 Difference between ingot and concast production processes.

6.1.3 Ingot casting for further hot working, rolling, forging and extrusion.

6.2 Basic Casting Production Methods - Finished Products

6.2.1 Methods of casting:

i) sand casting ii) die casting iii) investment casting

6.2.2 Basic defects associated with cast products, their appearance and how they are formed:

i) shrinkage ii) sinks iii) cold shuts iv) porosity v) laps vi) hot tears vii) cracks

6.2.3 Stress relieving. What stress relieving is and why it is carried out.


6.3 Wrought Products Forming Processes

6.3.1Rolling process:

i) primary rolling - blooms and slabs ii) secondary rolling - billets, sections and plates iii) cold rolling - sheets and strips, basic rolling defects, appearance and how they are formed

6.3.2 Forging:

i) open die forging and press forging ii) closed die forging

6.3.3 Basic forging defects, their appearance and how they are formed:

i) forging bursts ii) laps iii) seams iv) cracks

6.3.4 Extrusion:

i) definition of and how it works ii) why extrusion is used instead of rolling or forging

6.3.5 Annealing. How annealing is carried out and the results obtained:

i) full anneal and definitions ii) sub critical anneal and definition


6.4 Basic Welding Processes

6.4.1 Schematic lay out and general method of producing welds:

i) MMA ii) TIG iii) MIG/MAG iv) SA welding v) electroslag welding

6.4.2 Basic types of welds:

i) fillet welds ii) butt welds in plate, pipe, nozzle and nodes

6.4.3 Welding defects and how they are formed:

i) lack of fusion (all types) ii) porosity; worm holes, gas pores iii) cracks; centre line, HAZ iv) visual defects including misalignment v) lack of penetration vi) slag

6.4.4 In-service defects:

i) fatigue cracks ii) stress corrosion cracks

6.4.5 Welding terms. Definition of welding terms, part of the weld and adjacent parent plate.


6.4.7 Normalising. Definition of normalising and the differences to annealing.

7. Sector Specific Practical Testing

Refer to PCN/GEN Appendix E2.1.


8. Sector Specific Practical Instruction Writing

Refer to PCN/GEN Appendix E2.1. PCN publishes a document, CP25, for the information of candidates for this examination.

LEVEL 3 SYLLABUS

Level 3 personnel are expected to be competent to assume the responsibilities of management of an industrial NDT facility. The PCN level 3 examination will therefore evaluate the candidate's knowledge of the following:

Allocation of staff with appropriate certification according to customer's requirements. Supervision and maintenance of subordinate's certification and recertification documents and records.

Compilation of records of equipment performance, repairs and maintenance; the work done and results achieved by supervised staff. The review of reports of work done by subordinates, its periodic validation, and the endorsement of routine reports.

Review of current practices, equipment, techniques and instructions. Maintenance of standards and text book libraries. Safe working practices and current legislation.

9. General Theory

Candidates will be required to be familiar with all the content of the general theory syllabus for level 2 but the examination questions will be more complex.

10. General Theory of NDT Methods at Level 2

10,1 General theory at level 2, including limitations to application, of four NDT methods. The examination syllabi are detailed in appendices to PCN General Requirements and are obtainable from PCN or any of its test centres.

10.2 In detail, the level 3 candidate will be required to demonstrate a knowledge of the level 2 general theory syllabus covering the NDT method in which level 3 certification is sought and, in addition, three others selected by the candidate from RT, UT, PT, MT, ET and VT.

11. Knowledge of PCN Requirements

A thorough understanding of the PCN criteria for certification of all levels of personnel as applied in the current edition of PCN General Requirements for Certification of NDT Personnel.


Candidates will be required to be familiar with all the content of the specific theory syllabus for level 2 but the examination questions will be more complex. The level 3 candidate will also be expected to demonstrate familiarity with the criteria in codes and standards covering the application of liquid penetrant testing and flaw acceptance limits.

13. Materials Technology

This examination part will cover the syllabus given earlier for level 2 Product Technology, but the level 3 questions will require a greater understanding of the manufacturing processes and associated defects.

14. Sector Specific Practical Level 2

For level 3 candidates not holding or having held a PCN level 2 liquid penetrant testing certificate, the level 2 sector specific practical examination must be passed. Refer to PCN/GEN Appendix E2.1.

15. NDT Instruction Writing

For level 3 candidates not holding or having held a PCN level 2 liquid penetrant testing certificate, the level 2 sector specific practical instruction writing examination must be passed. Refer to PCN/GEN Appendix E2.1.


16. NDT Procedure Writing

16.1The candidate will be required to produce a comprehensive test procedure for a specific component to a provided standard or code.

NOTE. PCN publishes a document, CP25, for information and for use by candidates in this open book examination.

16.2 The procedure must include acceptance levels to specified application standards, liquid penetrant operator approvals, techniques, equipment and its calibration, reference documentation, the use of complementary NDT methods, the timing of inspection in relation to manufacture and testing procedures, surface condition of work, special contractual requirements, action to be taken in case of non-compliance and reporting instructions (implementation of the procedure).


REFERENCE LITERATURE

Essential Reading

BS EN 571-1: Penetrant Testing. Part 1: General principles for the examination.

BS EN 1289 Non-destructive examination of welds – Penetrant testing of welds Acceptance levels

BS EN 1330-1: Non-destructive testing-Terminology – Part 1 List of general terms

BS EN 1330-2 Non-destructive testing – Terminology – Part 2: Terms common to the non-destructive testing methods

BS EN ISO 3059 Non-destructive testing. Penetrant testing and magnetic particle testing. Viewing conditions.

BS EN ISO 3452-2 Non-destructive testing. Penetrant testing. Testing of penetrant materials

BS EN ISO 3452-3 Non-destructive testing. Penetrant testing. Reference test blocks

BS EN ISO 3452-4 Non-destructive testing. Penetrant testing. Equipment

BS EN ISO 12706 Non-destructive testing – Terminology – Terms used in penetrant testing

QPL 25135: Qualified Products List.

MIL-I-25135: Inspection Materials, Penetrants.

ASTM E1417 Standard practice for Liquid Penetrant examination.

Product Technology Classroom Training Handbook. Obtainable from Certification Services Division, The British Institute of Non-Destructive Testing, 1 Spencer Parade, Northampton NN1 5AA.

Training Course Notes. PCN requires candidates to have attended an approved course of training. Accredited Training Establishments are required to provide trainees with an up-to-date set of training course notes. These are considered essential reading.

REFERENCE LITERATURE

Recommended Reading

Air Registration Board, Civil Aircraft Inspection Procedure BL/10-9 (Aluminium Test Blocks).

Penetrant Testing: A practical guide. D Lovejoy. Chapman & Hall, 1991.

Principles of Penetrants. C. E. Betz, Magnaflux Corp., Chicago 1969.

Basic Metallurgy for Non-Destructive Testing. Edited by J L Taylor. The British Institute of Non-Destructive Testing, 1 Spencer Parade, Northampton, NN1 5AA.

Materials and Processes for NDT Technology, ASNT, 1985.

Liquid Penetrant Testing Classroom Training Book, ASNT, 1977.

Liquid Penetrant Testing programmed instruction book, ASNT, 1977.

Question and Answer Book, Levels 1, 2 and 3, Liquid Penetrant Testing, ASNT, 1980.

Level 3 Study Guide, Liquid Penetrant Testing, ASNT, 1980.

NDT Handbook, second edition, volume 2 Liquid Penetrant Testing (1982), ASNT.

Liquid Penetrant Testing, Student Package, ASNT.

Liquid Penetrant Testing, Instructor Package (overheads for training) ASNT.

NOTE. Some of the above are available only in reference libraries. For information on sources of the above recommended reading contact PCN.




PCN/GEN Appendix E2.3 Issue 5


SPECIMEN QUESTIONS FOR THE EXAMINATION OF PERSONNEL IN LIQUID PENETRANT TESTING FOR THE PRE & IN-SERVICE INSPECTION SECTOR



Specific Requirements for the certification of Personnel in Liquid Penetrant Testing of General Engineering Materials, Components and Fabrications.


Syllabus for the Examination of Personnel engaged in Liquid Penetrant Testing of General Engineering Materials, Components and Fabrications.

CONTENTS

LEVEL 1............................................................................................................................................ 2 LEVEL 2............................................................................................................................................ 2 LEVEL 3............................................................................................................................................ 4


LEVEL 1

General Theory of the Liquid Penetrant Method

1. Which of the following would assist the penetrant to enter sub-surface cracks in a component?

a) the materials surface finish

b) the penetrant viscosity

c) the inherent surface tension

d) none of the above

2. The only discontinuities which penetrant testing can detect are:

a) sub-surface

b) surface breaking

c) internal

d) contaminant filled

3. The term used to define the period of time that a developer has been applied is:

a) attraction time

b) development time

c) dwell time

d) drain time

Sector Specific Theory of the Application of the Liquid Penetrant Method to General Engineering Products

1. Consumables of a toxic nature may:

a) not be used at any time

b) be used on site work only

c) be used in accordance with the manufacturer's instructions

d) be used in small amounts

2. All surfaces to be examined using penetrant flaw detection should be initially:

a) welded

b) painted

c) clean

d) sandblasted

LEVEL 2


1. The property of a liquid which affects the speed of flow is:

a) surface tension

b) viscosity

c) contact angle

d) a combination of all the above


2. The corrosivity of a liquid penetrant is usually assessed by:

a) actual component testing

b) the manufacturer of the penetrant

c) samples of material left in contact for 24 hours and examined

d) samples of material left in contact for 16 hours and examined

3. If fluorescent penetrant is applied after an acid precleaning treatment:

a) the penetrant should dwell for twice the time specified

b) marking of the test piece may be evident

c) a decrease in brilliance of the penetrant may occur

d) an increase in brilliance of the penetrant may occur


1. The British Standard to be referred to for penetrant flaw detection is:

a) BS 6072

b) BS 4069

c) BS 4489

d) BS EN 571-1

2. To avoid the risk of fire, penetrants in cans should:

a) be stored away from direct sunlight

b) not be sprayed near or onto hot components

c) kept away from incandescent surfaces

d) be handled so as to avoid all of the above situations

Wrought Product Technology Theory

1. Poor forging temperature or too great a reduction in section can give rise to rupturing of the material, this is called a:

a) lap

b) seam

c) burst

d) inclusion

2. The failure of turbine blades at the junction of the blade and larger section where it will be attached to the rotor, can often be ascribed to cyclical stresses which are concentrated in this region. The failure mechanism is called:

a) stress rupture

b) intergranular fretting corrosion

c) fatigue

d) hot tearing

Casting Product Technology Theory

3. Large smooth voids or porosity in a casting results from:

a) turbulent flow of metal during pouring

b) segregation of alloy constituents

c) gas evolved before and during solidification

d) hot tearing in the thick sections of the casting


4. Discontinuities which originate in the cast ingot can often be reduced by a process which closes and welds the voids, as well as breaking up inclusions, this process is:

a) machining

b) welding

c) forging

d) cold extrusion

Welding Product Technology Theory

5. Gross worm hole porosity which breaks the surface of a submerged arc weld is most likely caused by:

a) damp flux

b) poor current connection

c) work oxide films

d) variation in joint fit-up

6. Which of the following will not be found in a TIG welded joint?

a) porosity

b) slag

c) crater cracking

d) incomplete penetration

LEVEL 3


1. Colour contrast penetrants are best viewed in:

a) a minimum of 500 lux white light

b) a minimum of 800 lux white light

c) a minimum of 10 lux white light

d) a minimum 800 microwatts per square centimetre white light

2. If fluorescent penetrant is applied after an acid pre-cleaning treatment:

a) the penetrant should dwell for twice the time specified

b) marking of the test piece may be evident

c) a decrease in brilliance of the penetrant may occur

d) an increase in brilliance of the penetrant may occur

3. When using a post emulsifier penetrant, the emulsifier time should be:

a) as long as the penetrant dwell time

b) one half of the penetrant dwell time

c) the same as the developer time

d) minimised whilst ensuring all excess penetrant has been removed


General Theory of NDT Methods at Level 2

The examination will test the candidate's understanding of the general theory at level 2 of four out of the radiographic, ultrasonic, eddy current, visual testing, magnetic particle and liquid penetrant NDT methods to enable him/her to recognise correct application but not necessarily to specify techniques.

1. Thin sheets of lead foil in intimate contact with radiographic film increase film density because they:

a) fluoresce and emit visible light which helps expose the film

b) absorb the scattered radiation

c) prevent backscattered radiation from fogging the film

d) emit electrons which helps darken the film

2. The fact that gases, when bombarded with radiation, ionise and become electrically conducting make them useful in:

a) X-ray transformers

b) X-ray tubes

c) masks

d) monitoring equipment

3. The most effective method of demagnetisation is:

a) AC aperture coil

b) reversing and decreasing DC

c) stroking with AC yokes

d) hammering along the length of the part

4. For fine, surface breaking cracks the best magnetic particle inspection medium is:

a) dry powder, black

b) dry powder, fluorescent

c) magnetic ink, black

d) magnetic ink, fluorescent

5. Water washable penetrants require longer dwell times than solvent removable versions because of the presence of:

a) emulsifier

b) stabiliser

c) penetrant remover

d) contaminants

6. The property of a liquid which affects the speed of flow is:

a) surface tension

b) viscosity

c) contact angle

d) a combination of all the above

7. In eddy current test systems where encircling coils are used, coupling efficiency is referred to as:

a) lift off

b) edge factor

c) fill factor

d) phase differentiation


8. When the voltage applied to a circuit and the current through the circuit both reach their maximums at the same time the voltage and current are:

a) additive

b) in phase

c) regenerate

d) out of phase

9. The angle at which the shear component of an incident beam is refracted at 90 degrees to the normal is called the:

a) normal angle of incidence

b) first critical angle

c) angle of maximum reflection

d) second critical angle

10. As frequency increases in ultrasonic testing the angle of beam divergence of a given diameter crystal:

a) decreases

b) remains constant

c) increases

d) varies uniformly through each wavelength

Knowledge of Requirements for PCN Certification

1. The minimum period of experience required to be eligible for the level 1 Liquid Penetrant examination is:

a) 3 months

b) 2 months

c) 1 month

d) 6 months

2. PCN candidates shall have near distance acuity, corrected or uncorrected, in at least one eye, such that the candidate is capable of reading:

a) Jaeger number 1 letters at not less than 30 cm

b) Jaeger number 1 letters at not more than 30 cm

c) Jaeger number 1 letters at 300 cm

d) Jaeger number 2 letters at 30 cm


1. The corrosivity of a liquid penetrant is usually assessed by:

a) actual component testing

b) the manufacturer

c) the penetrant is left in contact with a test piece for 24 hours, followed by examination

d) the penetrant is left in contact with a test piece for 16 hours, followed by examination


2. To reduce the corrosive effect of a penetrant, which chemical group should be maintained at a low level?

a) aqueous

b) halogens

c) thixotropics

d) volatiles

3. Which of the following flaws is most likely to be missed due to improper rinse techniques?

a) forging lap

b) deep pitting

c) shallow and broad flaws

d) the rinse techniques will not affect the detection of flaws

Materials Technology Theory

1. A common cause of solidification cracking in welds made with high deposition rate processes is:

a) hydrogen entrapment

b) contaminated flux or shielding gas

c) weld preparation has an unsatisfactory depth to width ratio

d) operator error

2. A casting discontinuity which is caused by gas release or the evaporation of moisture during solidification is:

a) microshrinkage

b) porosity

c) porous segregation

d) hydrogen induced porosity

3. The heat treatment process which is employed to give a soft ductile product, by recrystallisation of the material, is termed:

a) tempering

b) hardening

c) stress relieving

d) annealing

4. Poor through thickness ductility in rolled plate, often associated with non-metallic inclusions, gives rise to:

a) lamellar tearing

b) reheat cracking

c) uniform porosity

d) hydrogen cracking

5. The welding process which would be chosen for its rapid deposition rates, high welding speeds and deep penetration quality joints is:

a) electroslag

b) manual metal arc

c) submerged arc

d) TIG


6. Hydrogen cracking, due to the break down of water molecules creating hydrogen which dissolves in the weld metal and HAZ, is most likely to occur in which of the following welding processes?

a) TIG

b) MIG

c) sub-arc

d) MMA

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Dye Penetrate Test