In sieve plate column, holes are drilled or punched in sizes ranging from 2.5 to 12 mm (5 mm being widely used). The hole pitch is normally ______________ times the hole diameter to give the required hole area?

Related Mcqs:

1. A high vapour velocity is required for high plate efficiency in a sieve plate column. The satisfactory value of operating vapor velocity for design purpose in sieve plate column is about _______________ percent of the flooding velocity?

   A. 45
   B. 60
   C. 80
   D. 95

2. Holes of a sieve tray are arranged in triangular pitch of _________________ times the hole diameter?

   A. 1.5 to 2
   B. 2.5 to 5
   C. 5 to 10
   D. 10 to 15

3. A perforated plate has holes of diameter dn arranged in a pitch ph. Each hole has a tube of I.D. dt passing through it. The ligament efficiency is given by_______________?

   A. (ph – dh)/ph
   B. (ph – dh . dt/2)/ph
   C. (ph – dt)/ph
   D. (ph – dh)/dh

4. Hole diameter of the sieve trays in the distillation column ranges from ______________ mm?

   A. 1 to3
   B. 4 to 8
   C. 3 to 12.5
   D. 12.5 to 18.5

5. Pick out the wrong statement about the design of sieve plate column and the bubble cap column ?

   A. The downcomer design and the residence time in the downcomer is almost same for sieve
   plate and bubble cap columns
   B. Weir length for a bubble cap plate is the same as that for the sieve plate
   C. Weir height for a bubble cap plate column is the same as that for a sieve plate column
   D. Weir height in case of a bubble cap plate ranges from 50 to 150 mm and is higher than the
   sieve plate

6. Bubble cap diameter used for the distillation column having diameter ranging from 1.5 to 4.5 metres is about ______________ mm?

   A. 10
   B. 50
   C. 100
   D. 200

7. 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

8. For a 25 mm hole drilled in plates to be riveted, the shank diameter of the rivet should be _______________ mm?

   A. 25
   B. 23
   C. 26
   D. 27

9. Multiple blade paddle agitator is used for mixing high viscosity liquids/paste in which the paddle diameter is commonly 0.8 times the tank diameter. However, the width of the blade is in the range of ______________ times the paddle diameter?

   A. 0.1 to 0.25
   B. 0.3 to 0.5
   C. 0.5 to 0.6
   D. 0.65 to 0.80

10. In a distillation column, bubble caps are located on trays with a pitch of ______________ times the outside diameter of the caps?

    A. 1.3 to 2
    B. 1.6 to 2
    C. 2.5
    D. 1.5 to 3