ASME SB171 C71500 Transverse baffle, longitudinal baffle, Impingement plate for Heat Exchanger Application

ASME SB171 C71500 Transverse baffle, longitudinal baffle, Impingement plate for Heat Exchanger Application


Baffles are components of shell and tube heat exchangers which are used to support and fix the tubes in a defined position. There are different types of baffle configurations. The most popular type is the perforated plate in the form of a segmented circle. The segmental baffles are arranged so that the segmented section faces are disposed opposite to each other along a bundle of tubes at specified interval. No Tube in Window (NTIW) baffles, Helically-shaped baffles, full support baffle are other types that can be fabricated in our company. We are professional Baffles Plates For pressure vessel heat exchangers heaters condensers reboilers separators evaporators .



What is the minimum baffle spacing recommended?

Generally between 0.3 to 0.5 off the shell diameter with 50.8 mm (2 inch) being the minimum used

Equation:

0.3 * Shell diameter

to

0.5 * Shell diameter

So if for example we have a shell diameter of 356 mm (14 inch) then the minimum baffle spacing selected should be between 106.8 mm (4.2 inch) to 178 mm (7 inch).

See below for calculations:

0.3 * 356 mm = 106.8 mm (4.2 inch)

To

0.5 * 356 mm = 178 mm (7 inch)

With both values considered valid as they are both above the minimum recommended value of 50.8 mm (2 inch)


Double segmental baffle

What is Baffle to Tube Clearance?

Every tube inserted in baffle has a clearance between the tube outside diameter and the baffle hole diameter. This clearance allows the tubes to be inserted in to the baffle with ease. TEMA standards provide clearance optimum requirement values that is employed in industry. These requirements take in to account the spacing that need to be provided fir differential expansion and contraction between baffle plate and tubes. Certain amount of leakage through the clearances is permitted to reduce stagnant regions and to make turbulent conditions more uniform and reduce shell side pressure drop. The leakage also reduces deposits in stagnant areas.

If the clearances are large, it can cause excessive fluid bypassing resulting in fluid starving regions in shell with low fluid velocities