A. < 10
B. > 10
C. > 20
D. < 20
Related Mcqs:
- A cylindrical pressure vessel of volume 6 πm3 has to be designed to withstand a maximum internal pressure of 10 atm. The allowable design stress of the material is 125N/mm2 and corrosion allowance is 2 mm. The thickness of the vessel for a length/diameter ratio of 3 will be close to________________?
A. 5 mm
B. 6 mm
C. 8 mm
D. 10 mm - A certain pressure vessel manufacturer avoids doing reinforcements calculations for openings by always providing a reinforcing pad extending upto double the diameter of the opening and of the same material and thickness as that of the shell wall. If area compensation is accepted as a code guideline, his approach leads to safe design____________________?
A. Only if the opening is on spherical vessel
B. Only if the opening is on a vertical cylindrical vessel
C. Only if the opening is on a horizontal cylindrical vessel
D. Irrespective of the shape of the vessel - In case of a ‘thin’ pressure vessel, the ratio of its diameter to wall thickness is_________________?
A. < 10
B. > 10
C. > 20
D. 30 - For a cylindrical vessel of moderate height, the weld joint efficiency for joints parallel to the cylindrical axis is given as 1.0; while for joints along the girth (circumference) it is given as 0.8. In calculating the shell wall thickness using code formula for an internally pressurised cylindrical vessel, what value of weld joint efficiency should be used ?
A. 0.8
B. 0.9
C. 1.0
D. (0.8)0.5 - In case of a shell and tube heat exchanger, the minimum shell thickness for carbon steel (inclusive of corrosion allowance) depends on shell diameter and is in the range of ________________ mm?
A. 3-5
B. 5-11
C. 8-15
D. 12-18 - Tube wall thickness depends on the corrosiveness of the fluids and their operating pressure & temperature and is specified by Birmingham wire gauge (B.W.G)-a number which varies from 8 to 18 with the numbers 14 and 16 being more commonly used. Outside diameter of tubes varies from about 15 to 50 mm; however a tube of less than _____________ mm outside diameter is generally not recommended for fouling fluids ?
A. 16
B. 19
C. 28
D. 38 - A shell may by termed as thin if its thickness to diameter ratio is less than 0.1. The factor which can be neglected in the calculation of membrane stresses is________________?
A. Bending
B. Deformation
C. Shear
D. Elongation - Poisson’s ratio of a material is the ratio of unit lateral strain to the unit axial elongation within its elastic limit. The value of Poisson’s ratio for structural and pressure vessel steel may be taken as ____________________?
A. 0.01
B. 0.3
C. 0.75
D. 0.95 - In a shell and tube heat exchanger having square pitch, the shell side equivalent diameter is given by (where, P = pitch, d = outside diameter of the tube) ?
A. 4(P2 – πd2/4)/πd
B. (P2 – rd2/4)/rd
C. 4P2/πd
D. πd/4P2 - The ratio of tube length to shell diameter in case of liquid shell and tube heat exchanger ranges from__________________?
A. 2 to 3
B. 3 to 5
C. 4 to 8
D. 6 to 12