IMPELLER IMPACT ON PUMP EFFICIENCY · IMPELLER IMPACT . ON PUMP EFFICIENCY. The versatility of...
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IMPELLER IMPACT ON PUMP EFFICIENCY The versality of portable, automac priming trash pumps makes them ideally suited for many municipal and industrial sewage and wastewater applicaons. Selecng a pump with the opmal impeller type - enclosed or open - helps determine the overall field performance and operaonal cost of the pump. Enclosed Impeller Open Impeller Efficiency leading to lower fuel cost Low wear rate Inexpensive wear parts Less power for the same performance The example to the right shows the efficiency of an 8" Global Pump using an enclosed impeller versus an 8" competor pump with an open impeller. Open impeller pumps have a lower efficiency due to recirculaon between the impeller and casing. They also experience a higher impeller and casing wear rate between the impeller and the face of the casing. l/s m³/hr US gpm Head - ft Head - m 3750 20 10 30 40 50 3500 3250 3000 2750 2500 2250 2000 1750 1500 50 25 0 1250 75 1000 100 750 125 500 150 250 175 0 0 20 40 60 80 100 120 140 160 180 200 220 240 50 100 150 200 250 300 350 400 450 500 550 600 650 700 750 800 850 GLOBAL PUMP COMPETITOR 2000 rpm 2200 rpm 2000 rpm 1800 rpm 1600 rpm 1400 rpm 1200 rpm 1900 rpm 1800 rpm 1700 rpm 1600 rpm 21.1% 30 40 50 55 60 63 60 52 35 40.5% 58.3% 73.3% 78.9% 80.4% 78.7% 70%
Transcript of IMPELLER IMPACT ON PUMP EFFICIENCY · IMPELLER IMPACT . ON PUMP EFFICIENCY. The versatility of...
IMPELLER IMPACT ON PUMP EFFICIENCY
The versatility of portable, automatic priming trash pumps makes them ideally suited for many municipal and industrial sewage and wastewater applications. Selecting a pump with the optimal impeller type - enclosed or open - helps determine the overall field performance and operational cost of the pump.
Enclosed Impeller Open Impeller
Efficiency leading to lower fuel cost
Low wear rate
Inexpensive wear parts
Less power for the same performance
The example to the right shows the efficiency of an 8" Global Pump using an enclosed impeller versus an 8" competitor pump with an open impeller. Open impeller pumps have a lower efficiency due to recirculation between the impeller and casing. They also experience a higher impeller and casing wear rate between the impeller and the face of the casing.
l/s
m³/hr
US gpm
Hea
d - f
t
Hea
d -
m
3750
20
10
30
40
50
350032503000275025002250200017501500
50
25
0 1250
75
1000
100
750
125
500
150
250
175
0
0 20 40 60 80 100 120 140 160 180 200 220 240
50 100 150 200 250 300 350 400 450 500 550 600 650 700 750 800 850
GLOBAL PUMPCOMPETITOR
2000 rpm
2200 rpm
2000 rpm
1800 rpm1600 rpm
1400 rpm1200 rpm
1900 rpm
1800 rpm
1700 rpm
1600 rpm
21.1%
30 40 50 55 60 63 6052
35
40.5%58.3%
73.3%78.9%
80.4%
78.7%
70%
3 - CALCULATE THE FUEL SAVINGSUsing an average diesel fuel cost rate of $3 per gallon and a fuel consumption difference of 1.43 GPH, the competitor pump costs $4.29 per hour more to operate than the comparable Global Pump. A full year's operational savings using a Global Pump can pay for the purchase of the pump over its competition. Daily Savings = Fuel Cost/G x Fuel Consumption Difference/Hour x 24 Hours
= 3 x 1.43 x 24 = $102.96 in Fuel Savings Per Day
Annual Savings = Daily Savings x 364 Days = 102.96 x 364 = $37,580.40 in Fuel Savings Per Year
SAVINGS AS EASY AS 1-2-3Global Pump models are designed with a state of the art enclosed impeller that ensures both high efficiencies (fuel savings) and long component life leading to lower wear rates. These factors combine to provide you with savings that allow our pumps to pay for themselves in fuel savings much quicker than a comparable competitors pump.
1 - DETERMINE THE REQUIRED HORSEPOWERUnderstanding how much power is required to achieve a specific duty point illustrates how much energy and therefore fuel is required. To do so, we need to determine water horsepower, or the power water gains from a pump. We then determine brake horsepower, or the actual power required by the pump end, based upon its efficiency. The following example uses a duty point of 2500 GPM @ 100' of TDH to compare an 80% efficient 8" enclosed Global Pump impeller to a comparable, but only 60% efficient 8" open impeller pump.WHP = (Flow x TDH)/3960 GPM-F WHP = (2500 x 100)/3960 = 63
BHP = WHP/Pump Efficiency
Global Pump BHP = 63/.80 = 79 Competitor Pump BHP = 63/.60 = 105
2 - CALCULATE THE FUEL CONSUMPTIONA fuel consumption rate of .055 gallons per HP per hour is typical for an engine of the size used in this example.
Fuel Consumption = BHP x Fuel Burn Rate
Global Pump Fuel Consumption Competitor Pump Fuel Consumption79 x .055 = ~4.34 GPH 105 x .055 = ~5.77 GPH
Fuel Consumption Differential 5.77-4.34 = 1.43 GPH
IMPELLER IMPACT ON PUMP EFFICIENCY
GLOBAL PUMP10162 East Coldwater Road, Davison, MI 48423
Tel: 810.653.4828 Fax: 810.658.06321.866.360.PUMP www.globalpump.com
© 2018 Global Pump
Specifications reflect model pictured, and are subject to revision without notice. Global Pump is not liable for any consequential, incidental or indirect damages relating to these specifications.
