Pressure drop for heat exchangers 2

[Samingme755]

hi,
can anyone give me the deference between total pressure drop and the allowable pressure drop for heat exchangers?
thanks in advance

 

[crshears]

Given the complete lack of parameters, no.

 

[udyman]

Total Pressure Drop - The calculated pressure drop through the exchanger based on what conditions the exchanger is designed for (i.e. specified flows, densities, viscosities, etc.)

Allowable pressure drop - A specification provided by a process design engineer that is the maximum allowable design pressure drop (or total pressure drop) for that exchanger.

For example, I have a process where I have a pump that produces 50 psig head, going through an cooler to a tank at 10 psig. A control valve is designed for 15 psig pressure drop, and piping to the tank is expected to have 15 psig pressure drop. Thus there are 10 psig available for the cooler. The process design engineer could specify an allowable pressure drop of 10 psig in this case (though you would probably want to specify a little bit less).

 

[LittleInch]

Please provide the detials and example otherwise they look very similar definitions, but the devil is in the detail.

So e.g.toal could include valves, pipe work etc and allowable is just the HX itself? Who knows?

 

[pierreick]

Hi,
To make it simple:
total pressure drop = pressure drop calculated, result of simulation or hand calculation
Allowable pressure drop = pressure drop allowed by the system, example Fouling or existing pump /piping or erosion, ETC. This is specified according to Process

Pierre