Tube height in a calandria type evaporator is normally less than _______________ metres?

Related Mcqs:

1. Tubes are fixed to the tube sheet (a thick circular metallic plate) by the method of tube rolling and brazing (non-removable) or ferrule connection (removable). Thickness of the tube, sheet is normally ____________ the outside diameter of the tube but in no case it should be less than 22 mm (7/8″)?

   A. Half
   B. Three fourth
   C. Equal to
   D. 1.5 times

2. The ratio of down take area to cross-sectional area of the tube, for calandria type evaporator ranges from_________________?

   A. 0.5 to 1
   B. 1 to 1.5
   C. 1.5 to 2
   D. 2 to 2.5

3. In a vertical short tube evaporator (Calandria type), the ______________________?

   A. Tube dia of 2.5-7.5 cms, tube length of 75-200 cms and cylindrical drum dia of 1-6 metres are
   normally used
   B. Area of central downtake is equal to 40 to 100% of total cross-sectional area of the
   surrounding tube
   C. Liquor is inside the tube while the steam is outside the tube
   D. All A., B. & C.

4. Minimum tube pitch recommended for shell and tube heat exchangers is about _______________ times the outside diameter of the tube?

   A. 1.25
   B. 1.75
   C. 2.5
   D. 3.5

5. In most of the shell and tube heat exchangers, the tube pitch is generally ______________ the tube diameter?

   A. Less than
   B. 1.25-1.50 times
   C. 2.5 times
   D. one-fourth of

6. In a shell and tube heat exchanger, the overall heat transfer co-efficient is proportional to the tube side (volumetric flow rate)0.8. This is valid, only when the ratio of the tube side film resistance to the total resistance is almost equal to____________________?

   A. ∞
   B. 1
   C. 20.8
   D. 2

7. In packed towers provided with saddle packing, liquid redistributors are positioned at every _______________ times column diameter or 6 metres whichever is less?

   A. 2-3
   B. 5-8
   C. 10-15
   D. 20-25

8. 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

9. The clearance between two tubes in a shell and tube heat exchanger is known as ‘ligament’, whose minimum value is _____________ the outside diameter of the tube, but in no case it should be less than 4.5 mm?

   A. Equal to
   B. Half
   C. One fourth
   D. Three fourth

10. Width and depth of grooves in the tube sheet holes normally are _______________ inch respectively?

    A. 1/8 and 1/64
    B. 1/64 and 1/8
    C. 1/2 and 8
    D. 1/2 and 5