7 replies to this topic

[Sherif Morsi]

Hi,

 

I am currently reviewing the sizing calculation of a diaphragm pump (double acting) to issue the datasheet for purchase. I sized all the lines included in the new package. The flowrate is 4 m3/hr of Methanol (90% vol concentration) and the line is 2" SS316 #150. The discharge line from the pump is 120 meters until it reaches the methanol tank.

 

The pressure drop in the line (including friction, valves, fittings...etc) doesn't exceed 1 bar using the line sizing sheet (which I find logical in a sense).

 

The pump sizing sheet is accounting for the acceleration head, when calculating the required discharge pressure from the pump which is weird because I checked API 14E and the acceleration head is only used to calculate the NPSHa (so we are talking suction side only).

 

Does anyone find it right to account for the acceleration head loss on the discharge side of the pump?

 

Thanks,

Sherif

[fallah]

Sherif,

 

The acceleration head loss wouldn't come into discharge line losses calculation...

[Sherif Morsi]

I thought so as well.

 

Thanks,

Sherif

[latexman]

If the discharge line is seeing surging flow - acceleration, deceleration, acceleration, deceleration, etc. - why not?

[fallah]

latexman,

 

The difference in friction loss due to acceleration/deceleration at discharge line of the reciprocating pump would be covered by pump added energy.

[latexman]

fallah,

 

Thanks.  That was not clear to me in the past.  Your excellent response, followed by a little Googling, cleared that up nicely.

[breizh]

Sherif ,

Consider this resource.

 

Hope this helps.

 

Breizh

[Sherif Morsi]

Breizh,

 

Appreciate your shared resource

 

Sherif