Centrifugal Pump Basics Terms commonly used in the
Centrifugal Pump Basics Terms commonly used in the pumping industry
Centrifugal Pump Basics z Centrifugal, (Sen-trif’-u-gal) z. Tending to fly from a center z. Thrown from a center z Centrifugal pump impeller does just that z Water drawn into impeller eye, accelerated down the blades and thrown against pump casing that directs flow out of discharge
Centrifugal Pump Basics Centrifugal Pump Impeller Rotation Liquid into impeller eye from pump suction
Centrifugal Pump Basics Centrifugal Pump Curve
Centrifugal Pump Basics Centrifugal Pump Curve
Centrifugal Pump Basics Basic Fluid Facts z 1 Gallon of water (U. S. @ 60 Deg. F) weighs 8. 33 lbs 1” z 1 cubic foot of water contains 7. 48 gallons z Specific Gravity (Sp Gr) of a fluid is the relationship of the density (lbs/ft 3) to that of water (62. 3 lbs/ft 3) 1” 2. 31 ft 1 psig WATER COLUMN
Centrifugal Pump Basics Specific Gravity WATER 1. 0 sp gr GASOLINE 0. 8 sp gr BRINE 1. 2 sp gr 231 ft 100 psig 80 psig 120 psig Pump head (ft) = psig*2. 31 sp gr Pump Shut-off Head 231 ft hp = gpm*hd*sp gr*100 3960*Pump Eff
Centrifugal Pump Basics BASIC FLUID FACTS 1” 1 inch square column of air, the height of the earth’s atmosphere (From Sea Level) weights 14. 7 lbs 1” 0 psig Air Column 14. 7 psia
Centrifugal Pump Basics Basic Centrifugal Pump Equations For variations in impeller diameter, at constant speed: D 1 = Q 1 = D 2 Q 2 H 1 H 2 BHP 1 = D 13 BHP 2 D 23 For variations in speed, with constant impeller diameter: S 1 = Q 1 = S 2 = Q 2 H 1 H 2 BHP 1 = S 13 BHP 2 S 23 Where: D = Impeller Diameter (Ins / mm) H = Pump Head (Ft / m) Q = Pump Capacity (gpm / lps) S = Speed (rpm / rps) BHP = Brake Horsepower (Shaft Power - hp / k. W)
Centrifugal Pump Basics System Resistance Friction Loss for Water in Commercial Steel Pipe (Schedule 40)
Centrifugal Pump Basics Open & Closed Systems z A “Closed” hydronic system is one that has only one interface with air or flexible membrane z An “Open” hydronic system is one that has more than one interface with air or a flexible membrane
Centrifugal Pump Basics “Closed” System Balancing 3 -Way Isolating Valve Control Valve LOAD BUILDING HEIGHT LOAD EXPANSION SOURCE
Centrifugal Pump Basics “Closed” System Resistance Curve Friction Losses CAPACITY
Centrifugal Pump Basics “Open” System Static Head Static Suction Head CONDENSER
Centrifugal Pump Basics “Open” System Resistance Curve Friction Losses HEAD System Head Curve Total Static Head CAPACITY
Centrifugal Pump Basics “Closed” System with Minimum Maintained Pressure BALANCING VALVE 2 WAY CONTROL ISOLATING VALVE LOAD BUILDING HEIGHT LOAD EXPANSION SOURCE
Centrifugal Pump Basics “Closed” System Resistance Curve with Minimum Maintained Pressure Friction Losses HEAD System Head Curve Minimum Maintained Pressure CAPACITY
Centrifugal Pump Basics Terms commonly used in the pumping industry
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