RT fgf

RADIOGRAPHIC TESTING LEVEL – III (GENERAL) 1. The specific activity of radioactive isotopes is measured in: A. B. C. D.

Million electron volts (Mev). Curie per gram (c/g). Roentgen per hour (R/h). Counts per minute (C/min).

2. The range of specimen thickness that can be adequately recorded on radiograph is called ….. of the radiograph: A. B. C. D. E.

Sensitivity. Latitude. Accuracy. Intensity. Density.

3. Intensity of an X-ray is directly proportional to: A. B. C. D.

KV across the tube. Current through the tube. The penumbra of the radiograph The back scatter

4. Isotopes of the same elements have different number of _______ in the nucleus. A. B. C. D.

Neutrons. Protons Electrons Alpha particles

5. ‘Compton Effect’ is the mechanism, wherein the portion of X-radiation is absorbed and a portion is ……… A. B. C. D. E.

Used in producing secondary photons. Used in increasing energy of original photons. Used in dislodging protons from the nucleus. Used in dislodging electrons from the outer shell. None of the above.

6. Which of the following will not affect the definition of the radiograph? A. Scattering B. Geometry

C. Focal spot size D. Film graininess E. All of the above will defect radiographic definition. 7. Fluorescent screens are used: A. B. C. D.

Whenever possible. To improve the definition of the radiograph To prevent scatter radiation from reaching the film. Medical radiography.

8. Maximum film density to which the radiograph should be exposed is dependent upon the: A. B. C. D.

Intensity of the film viewer. Variation in the thickness of the specimen Speed of the film Graininess of the film

9. Which of the following are ionization radiations? A. B. C. D.

X-rays Gamma rays. Neutrons All of the above

10. What proportion of the light of the viewing screen is transmitted through a radiograph of density 2? A. B. C. D. E.

50% 20% 10% 1% 0.1%

11. Purpose of double coating of emulsion on X-ray film is to: A. B. C. D.

Increase the speed of the film. Decrease the speed of the film Decrease the contrast of the film Reduce the inherent unsharpness.

12. Water spots on the film can be minimized by: A. Rapid drying of the film.

B. Immersion of wet film in the wetting agent solution for 1 to 2 minutes. C. Using fresh fixer during the rinse cycle. D. Cascading water during rinse cycle. 13. Which of the following does not affect developer strength? A. B. C. D.

Exposure to air. Film grain size Density of the film Number of films processed.

14. In scintillation counters, ionization radiation is converted into: A. B. C. D.

Electrons Light photons Electronic charge All of above

15. Transport index for package containing radio-active material is decided by dose rate at: A. B. C. D. E.

Surface of the package. 1 meter from the package 1 foot from the package Two foot from the package None of the above.

16. Double wall double wall image technique is used for the radiography of: A. B. C. D. E.

Longitudinal welds in large pipes- 200mm dia or more Plate welds Circumferential welds in the large vessels. Tubular products with outside diameter less than 80mm. Corner joints in the pressure vessels.

17. The quantity of radiation striking the unit area of film: A. B. C. D.

Is the product of radiation intensity and time. Is the intensity per unit of time Is directly proportional to intensity and inversely proportional to time. Varies directly with intensity and exponentially with time.

18. Total natural and man made back ground radiation exposure is estimated to be: A. 2 mrem/yr. B. 20mrem/yr.

C. 200 mrem/yr. D. 1000 mrem/yr. E. More than 1000 mrem/yr. 19. Primary disadvantage of fountain pen type of ionization chamber to measure the amount of radiation received by personnel is the: A. B. C. D.

Delay is necessary before the results of the measurement are known. Inaccuracy of such device in measuring scattered radiation. Inability of such device to provide a permanent record of exposure. Cost of recharging such devices.

20. A sheet of lead with an opening cut in the shape of the part to be radiographed may be used to decrease the effect of scattered radiation, which undercuts the specimen. Such a device is called: A. B. C. D. E.

Mask. Filter. Back scatter absorber. Lead foil screen. Collimator.

21. Which of the following is the gas filled radiation detector? A. B. C. D. E.

Ionization chamber. G.M.tubes Proportional counter chamber. All of the above. A and C only.

22. A hundred curie cobalt – 60 source is to be placed at the center of iron sphere having 2m outside diameter. What should be the minimum thickness of the sphere, if does rate on the surface is not to exceed 10 mr/hr.? A. B. C. D.

36 mm 154 mm 302 mm 170 mm

23. Neutron radiography is useful for inspecting: A. B. C. D.

Hydrogen embattlement. Water entrapment Nuclear fuel. All of the above.

24. A 6 mm thick steel plate is exposed by double marker method. SFD = 250 mm and distance of film from plate = 10mm. The difference in shift of source side and flaw = 5 mm and difference in shift of source side and film side marker = 20mm. The location of flaw from film side surface: A. B. C. D.

1.5 mm 4.5 mm 3.0 mm 2.0 mm

25. Which of the following statement is correct regarding G.M. Tube? A. B. C. D. E.

Air is used as fill gas in these tubes Noble gases such as Argon, Helium, and Neon are used as fill gases. These are operated in ion saturated regions. These are frequently used in real time radiography Both B and C.

26. Van de Graff generator has --------- as one of its components: A. B. C. D. E.

Electromagnet. Belt of insulating material, traveling at high speed. Wave guide Pulse generator Villard circuit

27. In electron radiography, hard X-ray photons produce electrons from: A. B. C. D.

The lead foil. The surface of the specimen to be radiographed The copper and aluminum filter Both A and B above.

28. Beta emission is result of: A. B. C. D.

Neutron, Beta reaction Release from nucleus that have large number of neutrons. Electrons bombardment on tungsten target None of the above.

29. For 2.56 curie Iridium-192 source, what is the minimum cordoned off distance for the safe level of 0.2 mr/hr? A. 8 meters. B. 16 meters. C. 80 meters.

D. 160 meters. 30. 30. In the question 29, what is the minimum cordoned off distance, if lead sheet of 10.0 mm thickness covering full beam, is placed at 2 meters distance? A. B. C. D.

8 meters. 20 meters. 40 meters. 180 meters.

31. In the same condition as Q 30 (i.e. 10mm of lead sheet at 2 meters distance), what will be the effect on cordoned off distance, if the Iridium-192 source is replaced by Cobalt source of the same strength? A. B. C. D.

It should be more. It should be same. It should be less Cannot calculate unless source dimensions are also known.

32. At 2 ft distance from a radiation source, the radiation intensity density is 300 R/hr. what is the intensity at 8 ft from the source? A. B. C. D. E.

12 R/hr. 120 R/hr 18.75 R/hr. 28.5 R/hr. 75 R/hr.

33. The film density of radiograph taken with an exposure time of 1 min 30 sec at 10 mA resulted in a density of 1.6. What exposure time at 5 mA is required to be given to result in a radiographic density of 2.5 in identical development conditions? (INDUSTREX AA Film is used) A. B. C. D. E.

3 minutes. 5 minutes 20 seconds. 8 minutes 16 seconds. 100 minutes. 9 minutes.

34. It is desired to radiograph a 0.5” thick copper plate using 220 KV X-ray. The exposure required for this will be equivalent to that required for …….. thick steel specimen? A. 17.8 mm. B. 0.35 inch. C. 1.4 inch.

D. 22 mm 35. The effective focal spot of an X-ray unit is 0.1 inch in diameter. The thickness of the object is 1.0 inch. If the geometric unsharpness is 0.15 mm. What is the object to focus distance? A. B. C. D.

38 cms. 37.5 inches. 16.9 inches. 55 cms.

36. For a given exposure, a 2-4T sensitivity was achieved. What is the equivalent penetrameter sensitivity in % ? A. B. C. D.

1.5% 2% 2.8% 3.2%

37. ASME penetrameters for materials other than steel are identified by the notches on their sides. For material group magnesium, the penetrameter may be made of all magnesium or magnesium will be predominant constitute. It will have: A. B. C. D.

Two notches on one side and one end. Notches on two sides, one on each side Three notches on one side One notch on each end.

ANSWER QUESTION NO 38 TO 42 BASED ON FIGURE-B (ATTACHED) 38. The tenth value thickness for steel for source B is: A. B. C. D.

2 inches. 1 inch. 4 inches. 3 inches.

39. The half value layer for lead with source B is: A. B. C. D.

1.4 inches. 0.4 inches. 1.8 inches. 0.6 inches.

40. The half value layer for lead with source A is:

A. B. C. D.

0.075 inches. 0.75 inches. 1.36 inches. Cannot be determined from the data given in the data-sheet.

41. The source having highest effect on the holographic film (i.e. requiring minimum exposure time) is: A. B. C. D. E.

A. B. C. D. E.

42. The source having maximum change in exposure for small change in section thickness is: A. B. C. D. E.

A. B. C. D. E.

43. The general method of producing X-rays involves the sudden declaration of high velocity electrons in a solid body called a: A. B. C. D. E.

Focusing cup. Filament. Target Cathode. Anode.

44. The minimum wavelength in angstrom unit of an X-ray unit of a particular KV rating is given by: A. B. C. D.

12.375 / KV. Frequency x velocity KV/D. None of the above.

45. The number of disintegration’s per seconds in a radioactive source of 20 Ci activity is: A. B. C.

3.7 X 1010 2000000 7.4 X 1011

D.

300000 46. The temperature of the developing bath is normally limited to a maximum of …….. …and minimum of 20 deg.C. A. B. C. D. E.

22 deg. C. 30 deg. C. 25 deg. C. 25 deg. C. 50 deg. C.

47. X-ray machines A, B, C and D have focal spot size 1x1 mm, 0.51X1 mm 1X2mm., respectively. Which of these will give a radiograph with best definition? A. B. C. D.

A. B. C. D.

48. Fluorescent screens have an advantage over ordinary lead foil screens in that: A. B. C. D.

The exposure time is increased. The sensitivity is improved. The exposure time is reduced. The cost is greatly reduced.

49. Radiation intensity is measured in units of: A. B. C. D.

Milli REM. Curies. Roentgen per hour. Becquerels.

50. The activity of radioactive isotopes in S.I. units is given in the units of : A. B. C. D.

Becquerels Coulombs. Grays. Sieverts.

51. During manual development, if the film is not agitated which in the developer, it will lead to the film having: A. B. C. D.

Streaks. Discoloration. Scratches. Fog.

52. 2-2T sensitivity achieved on a penetrameter means that: A. The thickness of the penetrameter T = 2% of the job thickness and the diameter of the smallest hole visible on the radiograph = 2XT. B. The thickness of the penetrant T = 2% of the job thickness and the diameter of smallest hole visible on the radiograph is 2% of T. C. The sensitivity is same as 2% obtained by the wire type penetrameter. D. The thickness of the penetrameter T – 20% of the job thickness and the diameter of the smallest hole visible on the radiograph is 2% of T. 53. Radioisotopes are artificially produced by irradiation of pellets of target material with: A. B. C. D.

Thermal neutrons. Electrons Positrons Electrical discharges

54. A tenth value thickness for a specific radiation source of gamma rays is one inch of lead and the radiation intensity of 500 R/hr at 24 inches from the source. How many inches of lead are required to reduce the intensity to .25 mr/hr at 4 feet distance from the source? A. B. C. D.

About 4 inches. About 10 inches About 2 inches About 5 inches

55. Which one of following is not a specific condition which applies to a given exposure chart? A. B. C. D. E.

X-ray machine used Film type Processing conditions Radiation intensity Film density on which the chart is based.

56. The graininess of all the film: A. B. C. D.

Increase as the radiation becomes harder. Decreases with the KV increase. Is not dependent on KV. Is totally controlled by Lambert’s Law.

57. Specimen with uniform thickness and composition by definition have:

A. B. C. D.

High subject contrast Good definition High film contrast Low subject contrast

58. Fluoroscopic screens of zinc cadmium sulfide find occasional use in industrial applications. These screens normally are not subject to wear or deterioration from exposure to long term X-ray. Which one of the following will severely degrade this type of screen? A. B. C. D.

Cleaning of the screens with grain alcohol solvent. Prolonged storage in low humidity environment will cause crystals to hydrolyze. Exposure to ultraviolet radiation Contamination with nickel as little as one part per million will create after glow problems.

59. Allowable radiation exposure will be more on: A. B. C. D.

Whole body Feet and ankles Skin of whole body Cannot say unless type of source is also known

60. Which of the following radiation doses will have no detectable clinical effects? A. B. C. D. E.

100 rems. 200 rems. 400 rems All of the above will have detectable clinical effect. None of the above will have detectable clinical effect.

Maximum Allowable Radiation Exposure per Calendar Quarter (in REM) Description or Location Whole Body, head & Trunk, Active Blood forming organs, Lens of eyes or gonads Hands and wrists, feet and ankies Skin of whole body

REM Allowed 1.25 18.75 7.5

TABLE Lead

Steel TVL cm

HVL CM

TVL cm

Concrete HVL TVL cm cm

Source

RHM

HVL cm

Ir-192

0.5

0.5

1.63

1.55

5.1

4.8

15.7

Co-60

1.28

1.25

4.1

2.2

7.4

7.0

23

Radiographic Equivalent Factors

MAGNESIUM ALUMINUM TITANIUM STEEL COPPER ZINC BRASS LEAD

50

100

0.6 1.0

0.6 1.0 8.0 12.0 18.0

X-RAYS KV 150 220 400 0.05 0.12 0.63 1.0 1.6 1.4 1.4 14.0

0.08 0.18 0.71 1.0 1.4 1.3 1.3 12.0

0.71 1.0 1.4 1.3 1.3

1000

2000

0.9 1.0 1.1 1.1 1.2 5.0

0.9 1.0 1.1 1.0 1.2 2.5

GAMMA RAYS Ir 192 CE-137 CO-60 0.22 0.34 0.9 1.0 1.1 1.1 1.1 4.0

RADIOGRAPHIC TESTING LEVEL III (TESTING OF WELDS) PROCEDURE WRITING

0.22 0.24 0.9 1.0 1.1 1.0 1.1 3.2

0.22 0.34 0.9 1.0 1.1 1.0 1.0 2.3

Based on the attached R.T. Procedure-RS2, write a detailed instruction sheet for radiography of circumferential butt welds in process piping for following sizes: (1) 2” Sch 80 (O.D. = 2.375” W.T. = 0.218”) (2) 6” Sch 120 (O.D. = 6.625” and W.T. = 0.560”) It has further been agreed that: (1) Only X-ray will be used. (2) 120KV shall be used for thickness upto 6 mm. And 250 kV shall be used for thickness more than 6mm. (3) Penetrameter shall be DIN Type. (4) Film density shall be 1.6 minimum and 3.8 max. (5) Density variation in area of interest shall not be more than 0.8. Other requirements as shown in the procedure shall apply. Make suitable assumption if data given is not sufficient.

RADIOGRAPHIC TESTING PROCEDURE – RS-2 1.1 WELD TYPE TO BE TESTED (a) Circumferential butt joints in piles, process piping, jacket legs and other tubular. (b) Longitudinal butt welds in case of piles and legs and wherever required. (c) Plate to plate butt welds (d) Web to web butts in case of splices in beams. 1.2 MATERIAL AND THICKNESS RANGE Process Piping:

Thickness 5mm to 25.4mm

ASTM-106 Gr.B.

Plates:

6mm to 12mm

I.S.-226

Tubulars:

16mm and more

ASTM-436/IS 2062/API 2H

1.3 CODE FOR PROCEDURE AND INSPECTION Based on AWS D1.1 and ANSI B.31.3 (Process piping) 1.4 RADIATION SOURCE 1.4.1 a) Gamma rays: Ir-192 for thickness 6mm to 63mm.CO-60 for thickness > 63 mm. The source size should be lesser that 2mm. Square to minimize un sharpness.

1.4.2 b) X-ray:

Wherever placement and adjustment of Xray equipment is possible. X-ray at suitable KV rating shall be used for thinner section less than 8 mm.

1.5 FILM SELECTION Radiographs shall be made using a suitable film, so that atleast minimum radiographic quality required is obtained. The selection is to be based uoin type of source used and the material thickness.

Material thickness Radiation Source < 12mm

X-ray 120 KV X-ray 150 KV Gamma ray X-ray X-ray Gamma ray Gamma ray

12mm To 25mm > 25mm 1.6

TECHNIQUE

1.6.1

a) Panoramic

Film Speed High Medium Low High High Medium Medium

Trade Name/Brand Agfa gavert D-10 or equivalent D7, Cronex NDT-65 or equivalent D-4, NDT-55 or equivalent. D-10, NDT-75 equivalent D-7, NDT - 65 or equivalent D-7, NDT- 65 or equivalent D-7, NDT-65 or equivalent

Circumferential butt welds in tubulars > or = 10 shall be allowed to be radiographed by this technique wherever possible. In this technique, the radiographic source is kept at the centre of the tubular. The entire weld length shall be divided in equal segments depending upon the standard size of film cassette or “READY-Pack” available. Films shall be adjusted to have atleast 1” overlap on each side. In a full panoramic exposure atleast 3 penetrameters shall be used. Spaced at roughly 1/3 of the circumference apart. In case the panoramic exposure does not cover the entire weld then atleast one penetrameter shall be used for each quadrant of the weld being radiographed. Penetrameter shall be placed on the side nearest to the source (wherever possible). 1.6.1.2 b) DIRECTIONAL EXPOSURE This technique is applied for longitudinal butt welds in plates. It involves radiographing a certain length of weld at a one time directing the penetrating radiation towards it. This may be done with collimator wherever possible to minimize interference by scattered radiation. This also reduces the physiological risks to the operators involved in radiography. The length of film exposed in any single exposure thus depends upon source to film distance (SFD) and the standard film length/cassettes available. The basic idea is that the distance traversed by the penetrating radiation through the medium being subjected to radiography at the edge of the segment should not be greater than 1.1 times that at the centre of the segment. Two penetrameters shall be used one at each end of the exposed length of the film placed on the side nearest to the source of the radiation. Normal SFD for 25 mm. Thick plate and 300 mm length is 350 mm.

1.6.2.1 b) DOUBLE WALL EXPOSURE- SINGLE IMAGE VIEWING This technique may be followed for tubulars with outside diameter greater than 2-1/2” (65mm). The radiographic examination shall be done by viewing single image only. The source shall be located touching the outer side of weld on the side opposite to the location of the film. By this method only one image is obtained on the film. The number of exposures required may be as per the chart A: CHART-A NO OF EXPOUSURES FOR DIFFERENT SIZES SIZE OF THE TUBULAR 2” Sch. 80 2” Sch. 160 2” Sch.80 3” Sch. 160 or XX 5 4” Sch. 40 6” Sch. 40 6” Sch. 80,120,160 8” Sch. 20 8” Sch. 120 10” Sch. 120

MIN NO. OF EXPOSURES (DOUBLE WALL) 3 4 3 4 3 3 4 3 4 4

All piping with wall thickness less than or equal to schedule 80 may be radiographed in 3 segments. In any case there shall be atleast one penetrameter kept at each end of any individual exposure. In case of 2” I.D. lines, only one penetrameter may be allowed (if DIN type is used) because of the fact that the area covered by film is very small. For structural joints radiographs may be taken by dividing the joint into three equal segments, each to be radiographed with separate exposure. 1.6.2.2 DOUBLE WALL DOUBLE IMAGE (Non-overlapping images) Piping with nominal inside dia. 33 MM. TO 50 MM. > 50 MM.

% SENSITIVITY REQUIRED 3% 2% 1.5% 1%

For the lowest range a default in terms of the sensitivity (for gama radiography) may be waived at the discretion of inspector, in case the weld image appears clear enough. This waiver clause is added after considering the fact that due to the limited radiation spectrum of the radioactive isotope the sensitivity obtained is inherently lower than that obtainable by wide range X-ray spectrum. 2.2 IDENTIFICATION NUMBERS Every radiograph shall have an unmistakable identification number which shall be unique for the particular job being tested. Such information to be provided should include weld joint number, welders identification of sequential number of the radiograph (so that they may be arranged chronologically). These may appear as radiographic images on the screen in which case lead numbers and/or letters may be placed between the film cassettes and the work piece. If for some reason this is not done then the number may be inscribed on to the film by using sharp edge/point. In any case the information desired shall not obscure the area of interest which may include the entire weld and atleast 1 cms. On either edge of the weld. 2.3 LOCATION MARKERS Location markers shall be used on the specimen for demonstrating that the whole area requiring inspection has been covered. The image of these location markers for the co-ordination of the part with the film shall appear on the film without interfering with the interpretation with such an arrangement that it is evident that complete coverage is obtained. These marker positions shall be

marked on the parts and the position of the markers shall be maintained on the part during the radiography. Atleast two location marker shall be visible on each radiograph to identify the area or part being examined. For consecutive radiograph, one marker must be common to adjacent radiograph so that it is evident that the requisite coverage has been given. 2.4 RADIOGRAPHIC DENSITY The transmitted film density at the area of interest shall be 1.8min. for single film viewing for radiograph taken by X-ray source and 2.0 min for radiographs taken with gama ray source. The max. density should be 3.0 (This is subjected to the capacity of the illuminator which is being used. However the maximum density to be viewed shall not exceed 4.0). 2.5 MEASURING FILM DENSITY This may be done by (1) METHOD OF COMPARISON (2) USAGE OF DENSITOME In (1) the density of the area of interest is matched t0 compared with that of a density strip (provided by established film manufacturers) which shows the films of different densities. In (2) the densitometer is first set to zero at the illuminator intensity at the viewing point. The density reading is read off by keeping its photo cell linked sensor behind the film which is kept on the illuminator. Once the densitometer’s original reading is set the intensity of light in the illuminator must not be changed. 2.6 GEOMETRICAL UNSHARPNESS The geometrical unsharpness shall not exceed 0.5 mm for material thickness upto 2”. 2.7 WELD PREPARATION Weld surface irregularities shall be removed to such an extent that the resulting radiographic image due to such irregularities cannot mask or be confused with the image of any discontinuity. All radiographs shall be free from fogging (in the area of interest).

2.8 Processing defects, water marks, scratches, finger prints etc. shall be controlled to a minimum and only such film defects which are readily visible on the surface of film may be condoned. 2.9 SCREENS Lead intensifying screens shall be used in direct contact with both sides of the film. These screens shall be atleast 0.1 mm thick. The front an dback screens may be of the same thickness, but if the loss of details due to back scattered radiation is to be avoided a higher thickness back screen is to be used (Alternatively lead sheets may used to cover such films from back side as which are likely to be affected). In such cases the two different screens shall be indicated by printing “Front” and “Back” on each respectively. The screens shall be free from wrinkles, dirt, grease and scratches. 3.0 FILM PROCESSING Manual processing is done with the following: (1) (2) (3) (4) (5)

Developer tank Stop bath Fixer Running water tank Wetting agent Pan/Tank

The film is observed under a safe light, which will not photographically affect the film while developing is in progress. After visually verifying that the film is adequate developed (which essentially requires some experience in the field) which should take normally between 3-1/2 and 5-1/2 minutes at a temperature between 23 and 25 deg. C. The film is transferred to stop bath to halt the developing action and later to the fixer so that the image is fixed. After holding for about 5 minutes it may be kept in a running water bath for about 5-10 minutes then kept in a wetting agent pan to ensure that the water will not stick to it while drying. Film drying cabinet may be used in urgent cases. Use of the film drying cabinet may be done in urgent cases. This may be resorted to only if parameters do not change in large volume of work. 4.0 PERSONNEL EVALUATING RADIOGRAPHS: The personnel employed for interpretation of radiographs shall be certified to atleast Level-II or certified for carrying our interpretation of weld radiographs. They should have adequate knowledge of welding processes and welding related defects.

5.0 ACCEPTANCE CRITERIA: 5.1 Cracks & lack of fusion :

None permitted

5.2 Lack of Penetration

None permitted in Process Piping. For structural members, this condition may be permitted provided that the through thickness density in the questionable area does not exceed the density in parent plate.

:

5.3 Linear discontinuities Permissible : Thickness (mm.) (T) Less than 6 mm 6 mm. To 28 mm. Greater than 28 mm.

Max. length of single Discount (L) 2 mm 2/3 T 19 mm.

Cumulative in any 6T length of inspected weld (L.c.) 6 mm 2T 38 mm.

The minimum separation required for two discontinuities to be classified as separate shall be equal to twice the largest dimension of the larger of the discontinuities.

5.4 Rounded indications (width less than 3 X Length) Thickness (mm.) (T) Less than 6 mm 6 mm. To 25 mm. Greater than 25 mm.

Max. length of single Discount (L) 2 mm T/4 6 mm.

Cumulative in any 6T length of inspected weld (L.c.) 6 mm T 25 mm.

The minimum separation required for two rounded indications to be classified as separate shall be the largest dimension of the larger of the two indications.

RADIOGRAPHIC TESTING LEVEL – III (TESTING OF WELDS) 1. A butt weld has thickness=25mm. DIN IQI’s are used for the radiograph. The diameter of the thinnest wire seen as an image on the radiograph is 1.0 mm. The radiograph is: A. B. C. D.

Acceptable Not acceptable. To be taken up with Agfa D4 film only Meant to be radiographed only by gama rays.

2. A butt weld has thickness = 6 mm. It is radiographed with a DIN IQI. The radiograph shows the wire of 0.15mm diameter clearly visible. Your interpretation of this case is: A. B. C. D.

The radiograph is acceptable. The radiograph is not of acceptable quality The thickness of the weld is not covered by the specification. This radiograph should be taken by X-ray.

3. This film density as measured through the penetrameter on a radiograph is 2.5. There are two different thicknesses of test plate involved. On the thicker side density is 2.0 and on thinner side it is 2.20. Which of the following statements is applicable? A. The radiograph meets the density requirement. B. The job should be radiographed again with one penetrameter on each branch of the plate. C. The radiograph is not acceptable as per ASME Sec. VIII. D. Density variations are not covered in the procedure. 4. A job has thickness = 25 mm. It is to be radiographed. Which of the following is applicable? A. B. C. D.

The film must be exposed by gama ray on D-4 only. X-ray must be used provided that NDT-65 film only is used. X-ray must be used with NDT-65 o D-7 film only. Either X-ray or gama rays may be used with either D-7 or equivalent film.

5. For a pipe of 2” O.D., radiographs are taken by the Double wall technique with nonoverlapping images. The minimum number of exposures required as per the procedure to cover the entire weld is: A. Three-120 deg. apart. B. Two-90 deg. apart.

C. Four-90 deg. apart. D. None of the above. 6. For lower thicknesses of test material, the sensitivity criteria are: A. B. C. D.

Less stringent that for higher thickness. The same as those for higher thickness More stringent that those for higher thickness Representative of the film quality.

7. A pipe having O.D. = 20 inches and one inch thickness has girth weld which is required to be 100% radiographed. The panoramic technique is employed. The weld is covered by three panoramic technique is employed. The weld is covered by three films of size = 4” X 19”. 2% sensitivity is achieved and there is one penetrameter on each radiograph. The radiographs do not have any rejectable indication and density between 2.0 & 2.8. Which of the following statement is applicable: A. B. C. D.

Based on the radiographs joint is acceptable. The job is to be radiographed again using longer films. The penetrameter sensitivity could be improved None of the above statements are applicable.

8. A welding procedure qualification test is conducted on a flat plate of thickness = 1” and length = 12”. It is radiographed completely in one exposure on one film. A source to film distance of -------- inches is adequate to meet the requirements of the procedure. A. B. C. D.

14” 12” 20” 24”

9. A Radiograph is taken of a 1” thick pipe weld. Pipe O.D. is 12” and technique is panoramic. Sensitivity and density requirements are achieved with DIN IQI. The gama ray source was 2X2 mm. There was no rejectable indication evident on radiograph. The surveyor did not accept the radiograph and asked for re-shot. What is your opinion? A. The surveyor was not justified B. The surveyor was justified since the geometric unsharpness was beyond permissible limit. C. The sensitivity was achieved but the definition might have been poor. D. None of the above statements is true. 10. A pipe of 48” O.D. & thick was radiographed for girth weld by panoramic exposure covered in 16 equal segments identified as 0-1, 0-2,…15-0. Segments 2-3, 3-4, 4-5,

7-8,9-10 & 10-11 had repair marked, attended and reshot taken with panoramic exposure and IQI in 4-5&9-10 only. Resulting radiograph has acceptable density, sensitivity and weld quality. Inspector did not accept radiograph. In your opinion: A. B. C. D.

The inspector is not justified in his stance. The inspector is trying to show his own importance. The inspector has instructions to slow down the production rate. The inspector is justified.

11. In radiograph, tungsten inclusion will appear as: A. B. C. D.

White linear indications with branches. Dark linear indications. White spots. White spots surrounded by black rings.

12. On a radiograph, white circular indications were observed on the area adjacent to the weld. This could be due to: A. B. C. D.

Dirty developer. Weld spatter. Pitted plate. Porosity in the weld.

13. In radiography of long pipe line radiographed using double wall single image technique, penetrameters are placed on: A. B. C. D.

Source side. Film side. Either side. On source side unless geometric unsharpness exceeds the permitted value, then it can be placed on the film side.

14. Lack of penetration is a defect which can occur in: A. B. C. D.

Double sided welds in plates. Single sided welds in plates. Pipe welds. All of the above.

15. A discontinuity is observed in the radiographic image of a weld. The discontinuity is thin, linear, sharply distinct and has feathery branches. The description, most closely indicates a: A. Gross slag inclusion. B. Segregation.

C. Crack. D. Lack of penetration. 16. Which of the following is correct statement? A. In a panoramic technique, we must take number of shots, superimpose them on each other to get 3-D picture of the defect. B. To ensure that lack of side wall fusion is clearly visible on the radiograph, we must radiograph at an angle of 90 degrees to the plate surface. C. While radiographing 1” thick plate for 2-2T sensitivity, essential penetrameter hole size shall be 0.02”. D. None of above is correct statement. 17. While radiographing a butt weld in a rolled plate, which defect is not likely to be detected? A. B. C. D.

Slag inclusions in the weld. Cracks. Laminations in the parent material. All of the above defects will be easily detected.

18. A radiograph of a six mm. Thick stainless steel plate welded using high input GTAW welding shows a few faint white and dark lines adjacent to each other. Reradiographs with increased KV did not show these lines. The indications were probably due to: A. B. C. D.

Non-relevant indications Valleys between weld passes. Mottling. Non-metallic inclusions

19. A weld radiograph shows globules. The joint preparation for this weld is most probably: A. B. C. D.

Single “V” groove with back ship. Single “V” groove without back chip. Double “V” groove. None of the joint preparation listed above can result in the weld having globules.

20. Which of the figure given below is an illustration of the double wall single image. (DWSI) technique? A. A. B. B. C. C. D. None of the above figures drawn below illustrates DWSI technique.

Source

RADIOGRAPHIC TESTING LEVEL – III (TESTING OF CASTING/FORGINGS) 1. Smallest hole size in penetrameter No.5 is: A. B. C. D. E.

0.005 inch. 0.010 inch. 0.020 inch. 0.040 inch. Not indicated.

2. A 1.0 inch thick aluminum casting is to be radiographed. How much KV will you use? A. B. C. D.

140 KV 200 KV 300 KV Any of the above can be used.

3. Location markers shall be placed on film side when radiographing spherical castings: A. B. C. D.

Whose convex side towards the source. Whose concave side is towards the source and SOD is greater then inside radius. Whose concave side is towards the source and SOD is less than inside radius. Whose concave side is towards the source and SOD is equal to inside radius.

4. A 4.25 inch thick casting, which is to be later finishing machined to 3.75 inch is to radiographed. The penetrameter selection should be based on thickness of: A. B. C. D.

4.25 inch. 4.00 inch. 3.75 inch. 3.6 inch.

5. Which radiographs will you refer for acceptance of radiographic defects in valve body castings having thickness of 50 mm? A. B. C. D.

ASTM-E-446 ASTM-E-186 ASTM-E-280 Any of the above depending on severity level.

6. A 15mm long crack was observed in a 40 mm thick casting. This casting: A. Is acceptable as severity level 4 casting. B. Is acceptable as severity level 5 casting.

C. Is acceptable as severity level 5 casting provided nature of crack is proved to be of minor nature by fracture machnics test. D. Is not acceptable. 7. A severity level 2 casting showed shrinkage of level Cb-3 and no other defects. This casting: A. B. C. D.

Is acceptable. Is to be rejectable. Is to be accepted provided the defect is in the mid zone. It is accepted provided ASTM-E-186 reference radiograph is used for compression.

8. A 125mm thick severity level 1 casting showed non-metallic inclusions of level B–1. This casating: A. B. C. D.

Is acceptable. Is to be rejected. Is to be accepted provided the defect is in the mid zone. Is acceptable if agreed between the client and manufacturer.

9. A severity level 2 casting showed shrinkage of level Ca-3 and non metallic inclusion of level B-2. This casting: A. B. C. D. E.

Is acceptable Is to be rejected. Is acceptable provided thickness is more than 115mm Is acceptable provided defects are in the mid zone Both C and D.

10. Which of the following defect is not acceptable under any circumstances for severity level-3 casting? A. B. C. D.

Cracks. Chaplets. Iron chills. Both B and C.

11. Table-4 of DIN 1690 part-2 is applicable to: A. B. C. D. E.

20 mm. Thick steel castings. 100 mm. Thick stainless steel castings. 350 mm. Thick steel castings. All of the above. None of the above.

12. Which of the following discontinuity is caused due to insufficient amount of molten metal, when the casting is cooling? A. B. C. D.

Cracks. Hot tears. Shrinkage. Mottling.

13. Which of the following discontinuities normally occur where a thin section joins a thick section? A. B. C. D.

Shrinkage. Hot tears. Gas porosity. Rat tails.

14. Radiograph shows indications which are dark, round spots with smooth borders. Interpretation is: A. B. C. D.

Slag inclusion. Porosity. Shrinkage cavities. Rat tails.

15. Radiograph shows indications which are dark irregular shaped spots with undefined boundaries. This indicates: A. B. C. D.

Surface irregularities. Hot tears. Shrinkage. Sand inclusions.

16. Radiograph shows indications which are appearing as dark spots of irregular shape with defined smooth boundaries. This indicates: A. B. C. D.

Slag inclusion. Porosity. Infused chaplets. Cracks.

17. Radiograph shows indications which are clearly defined intermittent or continuous smooth dark lines. This indicates: A. Hot lines. B. Shrinkage. C. Cracks.

D. Any of the above. 18. In radiograph unfinished inserts appear as: A. B. C. D.

Intermittent low density lines along the boundary of the insert. Well defined dark lines along the boundary of the insert. Intermittent dark lines with branches. Infused inserts will not give any indication on the radiograph.

19. Mottling is observed in steel castings ……… A. B. C. D.

Of thin section with large grain size. Of thick section with fine grain size. At junction of thick and thin section. May disappear if radiograph is taken with lower KV.

20. A radiograph of steel casting shows an indication. It is not clear whether the indication is hot tear or shrinkage. Hot tear is not permitted. What is your reaction? A. B. C. D.

Reject since it is suspected to be hot tear. Carry out ultrasonic testing to confirm. Grind the suspected area and carry out MPT to confirm. Re-radiograph at higher KV to confirm.