Engineering review for feedwater pump of N03
Feedwater pump for N03 project was designed as below :
Rated pressure
: 17,5 Barg
Rated Flow
: 14 000 kg / hour
Temperature
: 105 deg C
By the pump supplied as type CR 20-17 A-F-A-E-HQQE - 96500518 | Grundfos with 105 degC water
as working fluid per specification as OEM as below :
Rated pressure
: 204 m
Rated Flow
: 21100 kg /hr
Temperature
: 105 deg C
NPSHr
: 2,24 m
While elevation of the deaerator mid point is at 9 meter as per elevation view below (Picture 3) so
the NPSHa as per Grundfos chart is 15 meters.
As the NPSHa at field is 15 meter or aqual to 1,5 BarA, and the NPSHr of pump is 2,25 meters or
equal to 0,225 Bar, tha sefe operating temperature is around 107 degC. As table stated below.
It also stated that the pump has suction strainer with mesh 60 for 4 inch dia. Of pipe. The pressure
around pressure drop is stated as graphic below :
Correction Factors:
o For finer mesh
baskets backed with a
perforated sheet, consider
the following correction
factors:
▪ 40 mesh: Multiply pressure
drops by 1.2
▪ 60 mesh: Multiply pressure
drops by 1.4
▪ 80 mesh: Multiply pressure
drops by 1.6
▪ 100 mesh: Multiply
pressure drops by 1.7
▪ 150 mesh: Multiply
pressure drops by 1.8
▪ 200 mesh: Multiply
pressure drops by 2.01.
Flow 61,6 gpm
Table 2 . Pressure loss to strainer size and flow
As specified as strainer pressure drop curve, the estimated pressure drop is :
ΔP = Pressure Loss x CF = 0,13 x 1,4 = 0,182 psi = 1,23 kpa
Bibliography
Pressure Drop Curves for Temporary Strainers (fdpp.com)
Water - Saturation Pressure vs. Temperature (engineeringtoolbox.com)
CR 20-17 A-F-A-E-HQQE - 96500518 | Grundfos