Correct use of ‘factor of safety’ is very important in equipment design. It is defined as the ratio of the___________________?

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. Factor of safety (i.e., overdesign factor) in heat transfer equipments is about _____________ percent more than the actual/theoretical design factor?

   A. 5-10
   B. 15-20
   C. 30-35
   D. 35-40

3. In the design of a bag filter, the gas temperature is an important consideration, as it affects the___________________?

   A. Gas density
   B. Gas viscosity
   C. Fibre selection
   D. All A., B. & C.

4. 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.

5. Welded joint efficiency in the design of chemical process equipment is taken as_________________?

   A. 0.55
   B. 0.75
   C. 0.85
   D. 0.95

6. The ratio of lateral strain to linear strain is termed as the___________________?

   A. Poisson’s ratio
   B. Bulk modulus
   C. Modulus of elasticity
   D. Shear modulus

7. 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

8. LMTD correction factor is used in heat exchanger design for____________________?

   A. Double pipe heat exchanger
   B. Multipass shell and tube heat exchanger
   C. Fouling fluids
   D. Counter flow of hot and cold fluids

9. It is not desirable to design a heat exchanger for LMTD correction factor, FT, of less than _________________?

   A. 0.99
   B. 0.95
   C. 0.80
   D. 0.55

10. Fouling factor must be included in the calculation of overall design heat transfer coefficient, when the liquid__________________?

    A. Containing suspended solids flows at low velocity
    B. Containing suspended solids flows at high velocity
    C. Is highly viscous
    D. Is of high specific gravity