ARAMCO CBT QUESTION WITH ANSWER & WELDING QC INSPECTOR

41)If Mechanical damage occurred on base metals what will be your course of

action?

If any Mechanical damage found on the base metal, conduct the thickness

measurement and Magnetic Particle Test or Penetrant Test to be conducted, if

it is within tolerance accept it otherwise submit the report to higher authority for

further action.

42)You have observed in the specimen certain defects, why do you consider it as

important and do the report of it, state two planar defects? What are causes for

the occurrence of it and how will you avoid it?

Defects: Is a rejectable one i.e., a discontinuity which exceeds the code limits is

defects. Depending up on the conditions and severity it has to be repaired.

The two planar defects are i) Lack of side wall fusion ii) Undercut.

i) Lack of side wall fusion: Contaminated surface may due to oil, grease, and

rust etc., and too narrow gap, current very low and improper manipulation of

electrodes.

Prevention: Bevel ends shall be thoroughly cleaned and free from detrimental

contaminants, appropriate root gap, welding parameter within the WPS range

and right manipulation of electrodes.

ii) Undercut : Due to excessive current, travel speed too high.

Prevention : Appropriate travel speed, welding parameters under control and

shall be within the WPS range.

43)What is the P No; for CS & SS?

 CS- P1

 SS-P8

44)Buttering or weld build up on the prepared surface shall not exceed

 Exceed the lesser of 1/3rd of base metal thickness or 10mm without the

prior approval of the company.

45) Internal misalignment of Butt joints shall not exceed

 1.5 mm

46)Fillet Weld Profiles

 Convex, Concave, Mitre

47)Explain E 8018

 E – Electrode

 80 – Tensile Strength

 1 –for all Position

 8 – Coating

48)The preheat shall be established over a minimum distance of

 75mm on each side of the weld.

49)Electrodes, filler wires, flux which standards to be used?

 ASME SEC II C

50)What equipment will use to determine oxygen level?

 Oxygen Scavenger

51)What is the surface temperature of PT?

 5˚ C to 52˚C

52)What is the F number for the filler wire ER70S?

 6

53)What are the duties of a QC Inspector for Consumable

receiving inspection?

i.

Check the Test Certificates (T.C.) of each batch of electrodes for the

conformance of parameters with respect to project requirements.

ii.

Check the availability of labels on each package units (Pack or Box) and

completeness of the information in them.

iii.

Check the condition of the package and electrode / filler wire. If any

damage found, it is reported for the corrective action.

iv.

Check the correctness of the batch No.; Electrode/Filler wire diameter and

other data with respect to the Test Certificate.

a. After inspection, the welding materials are stored in the warehouse or in

the welding consumables control room under ambient temperature.

b. All welding consumables shall be stored in racks, off the floor, in such a

way as to prevent any physical damage or contamination. Consumables

for the use on various types and grades of material shall be clearly

54) What is the exposure time for low hydrogen electrode?

 The electrodes may not be exceeded more than four hours, the exposure

may be extended to 8 hours if the electrodes are continuously stored in a

portable oven upto 65˚C minimum.

55)What are the things to be checked in sockolets?

 All fitting bores are to be concentric within 0.76mm for all sizes.

 To prevent cracking of a fillet weld install a 1.5 cardboard washer or

withdraw the pipe 1.5 mm from bottom of the socket before welding.

56)Why post heating is done on some pipe after the welding is over

 To maintain uniform homogeneous structure.

57)What are weldolets and sockolets? And where they are generally used?

 Weldolets and sockolets are self reinforced fittings.

 Weldolets are used for butt welded branch connections where standard

tee is not available due to size restrictions and the piping is at a

critical/high pressure service.

 Sockolets are used to socket welding branch connection which requires

reinforcing pads.

58)What is the density of steel?

 7.86 kg/m³

59)In 316L, what is the L stands for?

 L stands for low carbon steel

60)If heat input increases what will happen?

 Yield strength decreases

 Tensile strength decreases

 Percent in elongation increases

 Notch toughness slightly increases and then decreases

 Hardness decreases

 Cooling rate decreases ( R  1/ T0H) Where R is the cooling rate, T0 is

the preheat temperature, H is the heat input.

61) What is the cause of porosity?

 The presence of gas pores in a weld caused by entrapment of gas during

solidification is termed as porosity. The pores are in the form of small 

64)What is annealing and normalizing process?

 Annealing process is a heat treatment in which a sold state is heated and then

cooled at a slow rate.

 The annealing temperature and the rate of cooling depend on the material and

the purpose of the treatment. Annealing is used to effect any of the following

changes in metal:

 To relieve stress

 Induce softness

 Alter mechanical properties, electrical, magnetic or physical properties.

 Refine crystalline structure

 Remove gases

 Produce a definite microstructure.

 Normalizing process is a process in which a ferrous metal is heated to a suitable

temperature above the transformation range and is subsequently cooled in still

air at room temperature.

65)What are the characteristics of good welding cable?

 Wear and abrasion resistant

 High electrical resistance

 Good heat resistance

 The size of the cable required for a particular application depends on the

maximum amperage to be used for welding, the length of the welding circuit

(welding and work cables combined), and the duty cycle of the welding machine.

66)What are the tests required for analysis of consumables?

 Chemical Analysis ( ASME SEC II C )

 PMI (JERES-A-206)

67)What are the tests required for verifying supplementary essential variables?

 Notch toughness

68)What is an isotope? Different types of isotope? Explain the characteristics of

isotope?

 Atoms of the same element which are identical in their chemical behavior but

different from one another in the number of neutrons contained in their nuclei, and

thus have different atomic weights.

 Isotopes also act as flow tracers for detecting leaks in buried or inaccessible

equipment.

 Isotopes such as cobalt-60, cesium-137, and iridium-192

69)Name the instrument used for measuring density of photographic or

radiographic film?

 Densitometre

70)What are the factors on which the density of radiographic film depends?

The density of radiographic films depends upon the following: -

A. Total amount of radiation emitted by X-ray or gamma ray.

B. Amount of radiation reaching the specimen.

C. The amount of radiation passing through the specimen.

D. Intensifying action of the screen if used.

71)How will you calculate the geometric unsharpness in radiographic film?

Geometric unsharpness of the radiograph shall be determined in accordance

with:

Ug = Fd/D

where

Ug = geometric unsharpness

F = source size: the maximum projected dimension of the radiating source

(or effective focal spot) in the plane perpendicular to the distance D from

the weld or object being radiographed, in.

D = distance from source of radiation to weld or object being

radiographed, in.

d = distance from source side of weld or object being radigraphed to film.

73)Which markers are used on SS materials?

 Low halogens and Low sulfur less than 200 ppm

74)Define Arc blow?

 The deflection of an arc from its normal path because of magnetic

forces.

75)What are the standards for welding as JER Standard?

 JERES-W-011-Welding Requirements for On-Plot Piping

 JERES-W-010-Welding Requirements for Pressure Vessels

 JERES-W-012-Welding Requirements for Pipelines

 JERES-W-014-Weld Overlays and Welding of Clad Materials

 JERES-W-016-Welding of Special Corrosion-Resistant Materials

76)Write the weld layers?

I. Root

II. Hot Pass

III. Fill

IV. Cap

77)What are the Weldment Terms?

i. Weld Face