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________________?

Related Mcqs:

1. The design stress, which is more than the damaging stress, is the least unit stress that will render a member unfit for service before the end of its normal life. The design stress factor or factor of safety indicates the margin between design stress and the _______________ stress?

   A. Working
   B. Damaging
   C. Allowable
   D. None of these

2. 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

3. For a cylindrical internally pressurised vessel, which of the following closure types would withstand highest pressure, if each closure is of the same material and thickness ?

   A. Hemispherical
   B. Ellipsoidal (2 : 1)
   C. Conical
   D. Flat plate

4. The ends of a cylindrical vessel can be closed by a head, which can be one of the four shapes. For the same thickness, choose the one which can withstand the highest pressure ?

   A. Flat plate
   B. Hemispherical
   C. Torispherical
   D. Ellipsoidal

5. Corrosion allowance in the design of pressure vessel/chemical equipment is not necessary, if___________________?

   A. Plain carbon steel and cast iron parts are used
   B. Wall thickness is > 30 mm
   C. Material of construction is high alloy steel
   D. Both B. & C.

6. Circumferential (hoop) stress in a thin cylindrical vessel under internal pressure is _____________ the longitudinal stress?

   A. Half
   B. Equal to
   C. Twice
   D. Eight times

7. In a cylindrical vessel subjected to internal pressure, the longitudinal stress ζL and the circumferential stress, ζn are related by___________________?

   A. ζh = 2 ζL
   B. ζh = ζL
   C. ζh = ζL/2
   D. No relation exists

8. Generally, no corrosion allowance in wall thickness of a part is required, if the thickness is more than ______________ mm?

   A. 10
   B. 20
   C. 30
   D. 5

9. 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

10. The longitudinal stress induced in a thin walled cylindrical vessel under internal pressure is_________________?

    A. pd/2t
    B. pd/4t
    C. pd/t
    D. pd/8t