Plenty Mirrlees Pumps: Pump Performance

Pump 6 x 12	Pump 6 x 15	Pump 6 x 17	Pump 6 x 21
Pump 6 x 25	Pump 6 x 30	Pump 6 x 38	Pump 6 x 40
Pump 6 x 50	Pump 6 x 65	Pump 6 x 80	Pump 6 x 95
Pump 6 x 120

This page contains a series of pump performance tables. The tables are arranged in pump size order for both 60Hz and 50Hz electrical frequency. The tables provide at various electric motor approximate full load speeds the pump flow rate (GPM), power absorbed (BHP) and net inlet pressure required (NIP _R - PSIA) for various operating pressures (PSI) and viscosity (SSU).

3500 rpm					Qt = 44.95 gpm
ssu		Differential Pressure PSI
ssu		50	100	200	300	400	500	600	NIPr Psi a
Flow gpm	33	40.3	38.4	35.6	33.5
	40	40.7	39.0	36.5	34.6
	60	41.5	40.1	38.0	36.5	35.2
	100	42.3	41.2	39.6	38.4	37.4	36.5
	500	43.7	43.3	42.6	42.0	41.6	41.2	40.8
	1500	44.3	44.0	43.6	43.3	43.0	42.8	42.6
	14000	44.7	44.6	44.5	44.4	44.3	44.2	44.2
Power bhp	100	2.0	3.3	6.0	8.7	11.4	14.0	16.7	4.5
	300	2.5	3.8	6.6	8.3	12.0	14.7	17.4	5.5
	500	2.8	4.2	6.9	9.7	12.4	15.2	17.9	7.0
	700	3.1	4.5	7.3	10.0	12.8	15.6	18.3	7.5
	1500	3.9	5.4	8.2	11.0	13.9	16.7	19.5	8.0
	3500	4.8	6.3	9.2	12.2	15.1	18.1	21.0	10.0
	14000	6.3	7.9	11.2	14.5	17.7	21.0	24.3	>14.7

Lube Oil & Fuel Oil

Lube Oil Only

(typical pump performance table. Pump size 6x15 @ 3500 rpm - from 60Hz selection)

Determine if the pump is to run at 50 or 60 Hz electrical operating frequency. Ignore the listings against the frequency that does not apply.
Scan through the tables (from the smallest towards the largest pump sizes) until you see the approximate flow required appearing in the tables. This will indicate the likely range of pump sizes that will produce the flow required. Remember the most economic selection will be the smallest pump at eh highest speed that will satisfy all the duty conditions.
Examine the range of tables that contain the flow required and find the first table (smallest pump) that shows the approximate flow required at the intersection of the minimum duty viscosity row and maximum duty differential pressure column.
In the lower half of the table check along the viscosity row to read the NIP_R (net inlet pressure required) by the pump and ensure that this value is below the NIP_A (net inlet pressure available) from the system in which the pump has to operate. If the pump NIP_R is higher than the system NIP_A select a larger pump running at a slower speed.
Also in the lower half of the table read the power absorbed (BHP) for the corresponding viscosity and pressure. Note: 100 SSU is the minimum value of viscosity used for selecting absorbed power and NIP_R.CAUTION: When selecting a pump using the above procedure, it is important when selecting the electric motor power that maximum system pressure is taken into consideration. The electric motor should always be sized to cover the absorbed power at the system safety relief valve set pressure plus 10% (to cover pressure accumulation to full by pass pressure) at the maximum viscosity.
To determine more accurate values of flow and power interplate directly between the values of viscosity and pressure listed.
DO NOT interpolate the NIP_R value for intermediate viscosities. The value listed against the nearest viscosity higher than the maximum duty viscosity is the value of NIP_R that should be used to compare against system NIP_A.
DO NOT interpolate maximum allowable pressure for intermediate viscosities. The value listed against the nearest viscosity lower than the minimum duty viscosity should be taken as the maximum allowable pressure at the minimum duty viscosity.

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