Know and Understand Centrifugal Pumps Episode 14 ppt

Know and Understand Centrifugal Pumps - 50 - 40 - 30 - 20 - 10 - 0- 100 200 400 600 800 1000 2000 4000 6000 Figure 17-13 Figure 17-14 Use a ‘Y’ branch and not a ‘T’ branch. This will reduce turbulence. 244 Pump Piping Slight incline toward the Eccentric DRY Straight Pipe toward Pump Figure 17-15 Correct suction piping leading to the pump (Figure 17-15). 1'1 10 DIAMETERS . STRAIGHT PIPE Figure 17-16 ~ ~~~ You should respect 10 pipe diameters before the first elbow in the suction piping (Figure 17-16). Example: If the pump has a 6 inch suction nozzle, you should have 60 inches of straight pipe before the first elbow. 245 Know and Understand Centrifugal Pumps INCORRECT Concentric reducer "J - CORRECT - CORRECT Figure 17-17 Use an eccentric pipe reducer to connect to the pump suction nozzle (Figure 17-1 7). Don't use flange bolts to unite misaligned piping to the pump. This damages the flange faces and stresses the pump casing (Figure 17-18). INCORRECT CORRECT Fiaure 17-18 246 Pump Piping CORRECT DISCHARGE PIPING Discharge pipe diameter larger than pump discharge nozzle Instrumentation fromthelast obstruction (valve) is 8 diameters pipe upport. Reducer Fiaure 17-19 Index Ri4 absolute pressure (psia), 4 Affinity Laws, The, 39,98,99,235 impeller diameter, 42 air aspiration, 33 alignment techniques, 145 laser alignment, 146 reverse dial indicator alignment, rim and face alignment, 146 (ANSI)pump, 58, 138 145 American National Standards Institute American Petroleum Institute (MI) American Voluntary Standards (AVS), Archimedes, 77 atmospheric pressure (ATM), 4 Bachus & Custodio formula, The, bases, 148 bearing failure, 159 pump, 59 58 18,100 dirt and abrasion, 161 improper mounting, 160 vibration brinelling, 16 1 grease, 158 oil, 157 bearing lubrication, 157 bearing maintenance, 163 bearing seals, 167 mechanical seal, 167 labyrinth seal, 168 lip seal, 169 bearings, 155 ball bearing, 155 roller bearing, 156 bearing temperature, 165 Bernoulli’s Law/Principle, 3,29, 54 best efficiency point (BEP), 67, 130, brake horsepower (BHP), 40,76 203 canned motor pump, 63 cartridge concept, 214 cast iron, 233 cavitation, 25 preventing cavitation, 35 turbulence cavitation, 34 vaporization capitation, 29 centrifugal pump, 3,54 centrifugal volute pump, 56 chemical attack, 207 compression packing, 175 compression set, 208 corrosion, 233 corrosive liquids, 220 coupling alignment, 153 cryogenics, 220 crystallization, 2 19 cutwater, 47 dangerous liquids, 220 Darcypeisbach formula, The, 17, dial indicator, 148,222 discharge head, 10 discharge pressure, 7 drain pipe, 239 99 Index driver shaft alignment, 142 dry running pump, 220 dual volute pump, 141 eccentric pipe reducer, 246 efficiency curve, 76,80 elastomer, 189 energy (BHp) curve, 76,81 environment controls, 2 13 equipment alignment sequence, 153 erosion, 232 ethylene propylene, 206 external flush, 21 5 extrusion, 208 failure analysis, 227 family curves, 85 flow, 39,46 fluid velocity, 235 fluorocarbon, 206 friction head (Hf), 92 calculating the Hf, 97 gases, 220 gauge pressure (psig), 5 grout, 148 hard vacuum, 221 Hazen and Williams formula, The, 17,98 head, 39 head-flow curve, 76,78 heat, 189 heat exchanger, 218 high pressure, 189,221 high speed shafts, 189 high temperature, 220 high temperature pump, 138 high velocity shaft speed, 221 horsepower, 44 hot alignment, 147 H-Q curve, see head-flow curve impeller, 3, 48 conventional impeller, 66 impeller diameter, 42 open impeller, 70 overhung impeller, 57 pump impeller, 64 semi open impeller, 71 totally enclosed impeller, 71 turbine impeller, 65 in-flow pipe, 239 installation dimension, 2 12 internal re-circulation, 32 kinetic energy pump, 51 L/D factor, 135 lantern ring, the, 177 Laws of Similarity, The, 39 magnetic drive pump, 62 mechanical seals, 180, 184 back-to-back double seal, 196 balanced, 188 cartridge, 192 double seals, 194,218 face-to-face dual seal, 197 single, balanced, external, 187 single, balanced, internal, 186 single, outside-mounted, single, unbalanced, inside support systems for dual seals, 198 tandem dual seal, 195 minimum requirement curve, 76 misalignment, types of, 144 motor, the, 148 negative psi, 5 net positive suction head (NPSH), 12, 54,82 net positive suction head available (NPSHa), 13,14 net positive suction head required (NPSHr), 13,76,82 nitrile, 206 non-lubricating liquids, 220 non-metallic pump, 61 O-ring, 187,214 O-ring (the elastomer) failure, 204 ozone attack, 209 unbalanced, 186 mounted, 185 split, cracked or hard, 208 packing lubricant, 178 graphite, 178 mica. 178 249 Know and Understand Centrifugal Pumps molybdenum disulfide (moly grease), 178 Pascal’s Law, 4 perfluorocarbon, 206 pipe strain, 149 positive displacement (PD) pump, 2, 51 pressure head (Hp), 92 determining the Hp, 96 pressure measurement, 4, 6 pressure spikes, 190 properties of water, 16 pump efficiency, 50 pump head, 5 pump installation, 147 pump maintenance files, 226 pump packing, 180 pump performance curves, 76 pump piping, 238 pump shaft, 142 pump shaft packing, 171 pumping unit, 200 pumps in parallel, 120, 122 pumps in series, 120, 124 quench and drain, 217 reciprocating action, 172 regenerative turbine pump, 65 rotary action, 173 rotary turbine, 173 running alignment, 147 seal chamber pressure, 7 seal failure, premature, 202 shaft deflection, 128 shims, 149 skin formation, 220 slurries and suspended solids, 220 slurry seal, 217 soft foot, 150 solidification, 219 specific gravity, 6 specific speed, Ns, 73 speed, 40 static head (Hs), 92 determining the Hs, 96 stopa, 171 stuffing box, 171 Submergence Laws, 243 suction bell, 241 suction bypass, 2 15 suction head, 10 suction lift, 10 suction pressure, 7 suction specific speed, Nss, 66 sweetzone, the, 140 synthetic fibers, 174 Teflon, 177 thermal convection tank, 198 thermal jacketed seal chamber, 216 throttling, 236 total dynamic head (TDH), 92 total head, 9 tramp flange, 104 turbine pump, 58 turbo tank, 199 turbulence, 235 vacuum, 5 vane passing syndrome, 33 vapor pressure, 24 vaporization, 220 variable elevations, 110 variable frequency drive (VFD), 39 variable resistances, 116 vegetable fibers, 171 velocity head (Hv), 92 calculating the Hv, 97 velocity head formula, 28 vertical turbine pump, 60 viscosity, 48, 157 volute type pump, 128 vortex breakers, 239 water horsepower (WHp), 45 Watt, James 44 wear bands, 72 wear rings, 48,233 zerk (zirk) fitting, 163 ps are made up of several components and are ex,,, s has been lecturing to trifugal pumps for many ay have read his ‘Pump Rico, has combined his knowledge to produce this lively and and down to ea consulting engineeri understandable book needing an accessible account of centri ISBN: 185617 409 3 II ISBN 1-85617-409-3 II I II IUI 111111 II I I1 1111 . Know and Understand Centrifugal Pumps - 50 - 40 - 30 - 20 - 10 - 0- 100 200 400 600 800 1000 2000 4000 6000 Figure 17-13 Figure 17 -14 Use a ‘Y’ branch and not. graphite, 178 mica. 178 249 Know and Understand Centrifugal Pumps molybdenum disulfide (moly grease), 178 Pascal’s Law, 4 perfluorocarbon, 206 pipe strain, 149 positive displacement (PD). 33 alignment techniques, 145 laser alignment, 146 reverse dial indicator alignment, rim and face alignment, 146 (ANSI)pump, 58, 138 145 American National Standards Institute American