Le/D) for 90° elbow (medium radius) and 90°square elbow would be respectively around___________________?

Related Mcqs:

1. A head comprises of straight flange section, corner torus, section and central dished section. Crown radius and knuckle radius in a head is related respectively to the__________________?

   A. Central dished section and corner torus section
   B. Corner torus section and central dished section
   C. Central dished section and straight flange section
   D. Straight flange section and corner torus section

2. Pressure drop due to pipe fittings can be estimated by the equation, ΔP/ρ = 4f, (Le/D) (V2/2gc) where, Le = equivalent length of straight pipeline which will incur the same frictional loss as the fitting and D = diameter of the fitting. The value of (Le/D) (dimensionless) for 45° elbow and 180° close return bends would be respectively around______________________?

   A. 5 and 10
   B. 45 and 75
   C. 180 and 300
   D. 300 and 500

3. Practical dividing line between a ductile and brittle materials is suggested, when the ultimate elongation is about 5%. Generally, larger the knuckle radius, stronger is the corner torus section of a head. The knuckle radius provided should be less than ______________ of the head?

   A. 6% of I.D.
   B. 3 times the thickness
   C. Either A. or B., whichever is larger
   D. Either A. or B., whichever is smaller

4. (Le/D) for a Tee (used as elbow, entering run) would be around _______________________?

   A. 5
   B. 60
   C. 160
   D. 200

5. (Le/D) for a Tee (used as elbow, entering branch) would be ____________________?

   A. Less than that for Tee (used as elbow, entering run)
   B. More than that for Tee (used as elbow, entering run)
   C. Around 90
   D. Both B. and C.

6. Steam is preferred to be used as a heating medium in heat exchangers, because of its_________________?

   A. Low cost
   B. High latent heat
   C. Non-corrosive condensate
   D. High film co-efficient

7. In a double pipe (concentric) heat exchanger, the hydraulic radius for heat transfer (for a fluid flowing through the annulus) would be_________________?

   A. Same as that for fluid flow
   B. Less than that for fluid flow
   C. More than that for fluid flow
   D. D2 – D1 (D1 and D2 are I.D. of inner and outer pipes respectively)

8. Triangular pitch tube layout as compared to square pitch in a shell and tube heat exchanger________________?

   A. Permits the use of less tubes in a given shell diameter
   B. Facilitates comparatively easier external cleaning because of large clearance
   C. Permits the use of more tubes in a given shell diameter
   D. Both B. and C.

9. Shell side heat transfer co-efficient in case of square pitch as compared to the triangular pitch under similar condition of fluid flow and tube size is_____________?

   A. More
   B. Same
   C. Less
   D. Twice

10. What is the minimum recommended ligament for square pitch arrangement in case of heat exchangers ?

    A. 6.5 cms
    B. 6.5 mm
    C. Equal to tube I.D
    D. Equal to tube O.D