MATH AND MAINTENANCE FOR PUMPS AND BLOWERS TRAINING SEMINAR

Transcription

1 MATH AND MAINTENANCE FOR PUMPS AND BLOWERS TRAINING SEMINAR

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3 FORCE WEIGHT OF WATER MEASURED IN POUNDS PRESSURE = FORCE PER UNIT AREA WEIGHT PER UNIT AREA

4 PRESSURE (PSI) = FORCE (LBS) / AREA (IN 2 ) P (PSI) = F (LBS) / A (IN 2 ) F P A

5 FORCE (LBS) = PRESSURE (PSI) X AREA (IN 2 ) F (LBS) = P (PSI) X A (IN 2 ) F P A

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10 ONE CUBIC FOOT OF WATER FORCE = WEIGHT = 62.4 LBS PRESSURE (PSI) = FORCE (LBS) / AREA (IN 2 ) P (PSI) = F (LBS) / A (IN 2 ) P (PSI) = 62.4 LBS 1 FT 2 X 144 IN 2 /FT 2 P (PSI) = 62.4 LBS 144 IN 2 = PSI

11 P = PSI FOR ONE FOOT OF DEPTH PRESSURE DEPENDS HEIGHT OR DEPTH OF WATER DIAMETER OR AREA IS IRRELEVANT IF YOU DOUBLE THE DIAMETER OF A RESERVOIR OR CLARIFIER BUT THE DEPTH REMAINS THE SAME THE PRESSURE DOES NOT CHANGE

12 Dia = 30 feet Height = 20 feet

13 Height = 20 feet Dia = 30 feet Dia = 150 feet

14 F = Weight = Vol (gal) x 8.34 (lbs/gal) = A (ft 2 ) x H (ft) x 7.48 gal/ft 3 x 8.34 lb/gal = A (ft 2 ) x H (ft) x 62.4 lb/ft 3 A (in 2 ) = A (ft 2 ) x (144 in 2 /ft 2 ) P (psi) = F (lbs) / A (in 2 ) P = A (ft 2 ) x H (ft) x 62.4 lb/ft 3 A (ft 2 ) x (144 in 2 /ft 2 ) P = (psi/ft) X H (ft)

15 0.433 PSI / FT 1 FOOT / PSI 2.31 FT/PSI

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17 STATIC PRESSURE DEPENDENT ON WATER DEPTH (HEIGHT) HEAD

18 HEAD

19 STATIC PRESSURE DEPENDENT ON WATER DEPTH (HEIGHT) HEAD PRESSURE HEAD ELEVATION HEAD

20 PRESSURE HEAD PRESSURE HEAD ELEVATION HEAD SEA LEVEL ELEVATION HEAD

21 STATIC PRESSURE PIEZOMETRIC SURFACE DEPENDENT ON WATER DEPTH (HEIGHT) HEAD PRESSURE HEAD ELEVATION HEAD DYNAMIC PRESSURE FRICTION LOSS

22 DEFINITION THE HEAD, PRESSURE OR ENERGY (SAME THING) LOST BY WATER FLOWING IN A PIPE AS A RESULT OF TURBULENCE CAUSED BY THE VELOCITY OF THE FLOWING WATER AND THE ROUGHNESS OF THE PIPE OR RESTRICTIONS CAUSED BY FITTINGS.

23 AKA SMOOTHNESS C-FACTOR HIGHER C-FACTOR SMOOTHER PIPE GREATER CARRYING CAPACITY SMALLER FRICTION LOSS C-FACTOR MAY DECREASE AS PIPE AGES PIPE DEPOSITS TUBERCULATION

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26 INCREASING VELOCITY INCREASES FRICTION LOSS Q = A x V V = Q / A FLOW IF FLOW INCREASES VELOCITY INCREASES AREA IF AREA DECREASES VELOCITY INCREASES DIAMETER IF DIAMETER DECREASES VELOCITY INCREASES

27 MAJOR LOSSES AKA FRICTION LOSSES LOSSES IN THE PIPE MINOR LOSSES LOSSES DUE TO FITTINGS

28 HYDRAULIC GRADE = ELEVATION HEAD + PRESSURE HEAD

29 H.G. HYDRAULIC GRADE H.G. PSI HEAD PSI HEAD ELEVATION HEAD SEA LEVEL ELEVATION HEAD

30 HYDRAULIC GRADE = ELEVATION HEAD + PRESSURE HEAD EQUIVALENT TO THE ELEVATION OF THE WATER SURFACE IN A RESERVOIR

31 H.G. WATER SURFACE ELEVATION SEA LEVEL

32 HYDRAULIC GRADE = ELEVATION HEAD + PRESSURE HEAD EQUIVALENT TO THE ELEVATION OF THE WATER SURFACE IN A RESERVOIR HYDRAULIC GRADE LINE LINE CONNECTING HYDRAULIC GRADES

33 H.G. HYDRAULIC GRADE LINE H.G. HEAD HEAD ELEVATION ELEVATION SEA LEVEL

34 HYDRAULIC GRADE = ELEVATION HEAD + PRESSURE HEAD EQUIVALENT TO THE ELEVATION OF THE WATER SURFACE IN A RESERVOIR HYDRAULIC GRADE LINE LINE CONNECTING HYDRAULIC GRADES ALWAYS SLOPES DOWN IN THE DIRECTION OF FLOW FLAT AT NO FLOW WHAT CAUSES HYDRAULIC GRADE LINE TO SLOPE DOWN FRICTION LOSSES

35 H.G. HYDRAULIC GRADE LINE FRICTION LOSS HEAD HEAD ELEVATION SEA LEVEL ELEVATION

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39 WORK ENERGY NEEDED TO MOVE ONE POUND MASS ONE FOOT MEASURED IN FT-LBS HORSEPOWER ENERGY PER MINUTE ONE HORSEPOWER DEFINED TO BE 1 Hp = 33,000 FT-LBS/MIN

40 MEASUREMENT OF THE AMOUNT OF ENERGY DELIVERED TO WATER WHp = Q (gpm) x TDH (feet) x 8.34 lbs/gal 33,000 (ft-lbs/min)/hp WHp = Q (gpm) x TDH (feet) 3,960

41 TOTAL HEAD PRODUCED BY THE PUMP MEASURED IN FEET STATIC HEAD STATIC SUCTION HEAD

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45 NEGATIVE SUCTION HEAD MAXIMUM THEORETICAL SUCTION LIFT 34 FEET MAXIMUM PRACTICAL SUCTION LIFT FEET

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48 TOTAL HEAD PRODUCED BY THE PUMP MEASURED IN FEET STATIC HEAD STATIC SUCTION HEAD STATIC DISCHARGE HEAD DYNAMIC HEAD IMPACTS FRICTION LOSS VELOCITY HEAD DYNAMIC HEAD DYNAMIC DISCHARGE HEAD DYNAMIC SUCTION HEAD

49 SUCTION LIFT CONDITION

50 SUCTION LIFT CONDITION

51 SUCTION LIFT CONDITION

52 SUCTION LIFT CONDITION

53 SUCTION LIFT CONDITION

54 SUCTION LIFT CONDITION

55 SUCTION LIFT CONDITION

56 SUCTION LIFT CONDITION

57 SUCTION LIFT CONDITION

58 FLOODED SUCTION CONDITION

59 THE HORSEPOWER REQUIRED TO DRIVE THE PUMP AKA BRAKE HORSEPOWER EFFICIENCY MEASURES PUMP S ABILITY TO CONVERT PUMP HP TO WATER HP PUMP EFFICIENCY = MECHANICAL EFFICIENCY

60 PHp = WHp EFF PUMP WHp = Q (gpm) x TDH (feet) 3,960 PHp = Q (gpm) x TDH (feet) 3,960 x EFF PUMP

61 MOTOR EFFICIENCY = ELECTRICAL EFFICIENCY

62 MHp = PHp EFF MOTOR PHp = Q (gpm) x TDH (feet) 3,960 x EFF PUMP MHp = Q (gpm) x TDH (feet) 3,960 x EFF PUMP x EFF MOTOR

63 MEASURED IN WATTS OR KILOWATTS TOTAL CONSUMPTION IS BASED ON OPERATING TIME IN KILOWATT-HOURS (KWH) Hp =.746 KW (KILOWATTS) COST = Hp x.746 KW/Hp x OP HRS x CENTS/KWH

64 EFF = EFF PUMP x EFF MOTOR EFF = WHp x PHp = WHp PHp MHp MHp ELEC MHp EFF M PHp EFF P WHp