API 653 PREPARATORY COURSEExam 1 – Open Book

Note: Tick only one alternative which you think is most appropriate.

1. AST fabricated to API 650 is normally designed not to exceed an operating temperature of:

a. 260 deg C b. 100 deg C c. 90 deg Cd. 21 deg C.

2. 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. 2” for single-welded lap joints and 4” for double welded lap jointsb. 1” for single-welded lap joints and 2” for double welded lap jointsc. 1.5” for single-welded lap joints and 2” for double welded lap jointsd. 1.5” for single-welded lap joints and 1” for double welded lap joints

4. 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 :

Where, Tt = 2.6 D (H –1)

Sta. 0.935” b. 0.985” c. 1” d. 0.922”

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. 5mm b. 2.4mm c. 1.6mm d. 3mm

7. Vertical joints of a 28mm 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. One spot on 50% of radial joint b. One spot on 10% of radial jointsc. Full radiography of all radial jointsd. RT – Nil; only MT of 100% joints is adequate.

9. As per API Std. 650, personnel who perform and evaluate radiographic examinations (RT) shall have a minimum qualification as follows:

a. Shall have a vision of Jaeger No.2b. Shall be qualified as Level II of ASNT SNT-TC-1A c. Shall not be color blindd. Shall have an experience of at least ten years in RT.

10. The minimum required shell thickness of a Tank of 60 Meter diameter (200 ft. diameter), built to API Standard 650, shall be:

a. Design shell thickness plus corrosion allowanceb. Hydrostatic Test shell thicknessc. 8 mm (5/16”)

d . G r ea t e r o f 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. Not requiredb. Requiredc. Depends on opinion of design engineerd. Depends on opinion of tank inspector

12. 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, 11, 12 Joules b.18, 24, 12 Joules c.24, 22, 10 Joules d.20, 10, 27 Joules

API 653 PREPARATORY COURSEExam 1 – Open Book

Answer Key

1 C2 C3 B4 A5 D6 A7 A8 A9 B10 D11 B12 B13 -------------------------------141516171819202122232425