DAILY EXAM 1 (OPEN) Note: Encircle the letter of only one answer which you think is most appropriate.
1.
AST fabricated to API 650 (Basic Standard) is normally designed not to exceed an operating temperature of: a. b. c. d.
2.
260 deg C 100 deg C 90 deg C 21 deg C
Minimum size of fillet welds in the construction or repairs of an AST built to API Standard 650 is: a. Higher of 6 mm (0.25”) or half of the thickness of thinner plate joined. b. Higher of 9 mm (0.25”) or one third of the thickness of thicker plate joined. c. Higher of 5 mm (0.1875”) or one third of the thickness of thinner plate joined. d. Lower of 6 mm (0.25”) or half of the thickness of thinner plate joined.
3.
As per API Standard 650, the overlap at lap-welded joints shall be at least five times the nominal thickness of the thinner plate, but need not exceed, a. b. c. d.
4.
2” for single-welded lap joints and 4” for double welded lap joints 1” for single-welded lap joints and 2” for double welded lap joints 1.5” for single-welded lap joints and 2” for double welded lap joints 1.5” for single-welded lap joints and 1” for double welded lap joints
Calculate by the 1-Foot method the design shell thickness Td in inches, of the following description of tank built to API Standard 650: H = Design liquid level = 50 feet D = Nominal Tank Diameter = 180 feet G = Design Specific Gravity = 0.86 CA = Corrosion Allowance = 0. 0625” Sd= Allowable stress in design condition, in psi Shell Material = ASTM A36M Td = design shell thickness, inch(es) St= Allowable stress for hydrostatic test condition, in psi Tt = hydrostatic test shell thickness, inch(es). Where, Td = 2.6 D (H –1) G + CA Sd a.0.912” b.0.850” c.1” d.0.922”
5.
Calculate by the 1-Foot method the hydrostatic test shell thickness Tt in inches, of the above referred tank, when water is used for the test :
a. b. c. d. 6.
Maximum Reinforcement thickness of vertical butt joints of a tank shell plate of 28mm, of an AST built to API Standard 650 shall be: a. b. c. d.
7.
Where, Tt = 2.6 D (H –1) St 0.935” 0.985” 1” 0.922”
5mm 2.4mm 1.6mm 3mm
Vertical joints of a 28 mm thick shell of an AST built to API Std. 650 shall be radiographed to the extent as given below : a.Full b.Partial c.Spot d. Nil
8.
In an AST built to API Standard 650, the bottom annular plates have radial weld joints, and are single butt welded with permanent back-up bar, in which case, the extent of radiographing radial joints shall be, a. b. c. d.
9.
As per API Std. 650, personnel who perform and evaluate radiographic examinations (RT) shall have a minimum qualification as follows : a. b. c. d.
10.
One spot on 50% of radial joint One spot on 10% of radial joints Full radiography of all radial joints RT – Nil; only MT of 100% joints is adequate.
Shall Shall Shall Shall
have a vision of Jaeger No.2 be qualified as Level II of ASNT SNT-TC-1A not be color blind have an experience of at least ten years in RT.
The minimum required shell thickness of a Tank of 60 Meter diameter (200 ft. diameter), built to API Standard 650, shall be: a. b. c. d.
Design shell thickness plus corrosion allowance Hydrostatic Test shell thickness 8 mm (5/16”) Greater of a, b, c
11.
Determine whether impact testing is required for A516 gr 70 normalised plates 1 inch thick, Design temp = 0 degree F (-18 degree C): a. b. c. d.
12.
Not required Required Depends on opinion of design engineer Depends on opinion of tank inspector
Which of the following sets of the Transverse Charpy V-notch Impact Test Values of a fully killed 0.75 “ thick plate of ASTM A 516 gr 60 for a design metal temperature of -34 degree C, is acceptable as per API 650? Plates are not normalized. a.20, b.18, c.24, d.20,
11, 12 Joules 24, 12 Joules 22, 10 Joules 10, 27 Joules
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
C Ref.: API 650, 1.1.1 C Ref.: API 650, 3.1.3.3 B Ref.: API 650, 3.1.3.5 A Ref.: API 650, 3.6.3.2 (td) D Ref.: API 650, 3.6.3.2 (tt) A Ref.: API 650, 5.2.1.5 A Ref.: API 650, Fig. 6-1, Note 6 A Ref.: API 650, 6.1.2.9 B Ref.: API 650, 6.1.3.2 D Ref.: API 650, 3.6.1.1 B Ref.: API 650, Table 2-3B & Fig. 2-1 B Ref.: API 650, Table 2-4 -----------------------------------------------
DAILY EXAM 1 (OPEN)
