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WA9302A-CS 950612 SHIMEK, JACOBS & FINKLEA CONSULTING ENGINEERS 8333 Douglas Avenue,//820 Dallas, Texas 75225 (214) 361-7900 ROS$ L. JACOB3, P.E. RoNALD v. CONWAY. P... ~ JOHN W. BIRKHOFF, P.E. JOE R. CARTER, P.E. GARY C. HENDRICK3, P.E. June 12, 1995 C. L. SHIMEK, P.E. I. C. FINKLEA, P.E. JAMES E. LAUGHLIN, P.E. Mr. Howard Pafford Water Utilities Superintendent City of Coppell Post Office Box 478 Coppell, Texas 75019 Re: Village Parkway Pump Station Expansion Pump Selection Dear Mr. Pafford: As you are aware, and as provided in our engineering services agreement for this project, the final selection of the pumps for the Village Parkway Pump Station Expansion is the responsibility of the City of Coppell. However, since we have converted your water system analysis database to the Cybernet format, we were easily able to prepare system curves for your use and aid in the selection of the proper pumps for the hydraulic condition and design parameters specified. We are enclosing one copy each of system-head curves we developed for the Village Parkway Pump Station Expansion project. The system curves were developed using the Cybernet Hydraulic model and the water system data we converted from the recent Kimley-Horn water system report. These system curves were developed on the basis that the pump station expansion is to serve as a system operational enhancement rather than to add system pumping capacity. For that reason, when evaluating the system head curve, we assumed in all alternatives and design years that the following conditions applied: 1) No other pumps in the system are running. This includes the 3-450 horsepower pumps at Village Parkway Pump Station and the future Belt Line Road Pump Station scheduled to come on line in the year 2004. If the proposed pumps (pumps no. 5 & 6) are to provide operational flexibility and not system capacity, then this seems to be a reasonable assumption. Basing the pump selection on this condition will assure a pump that has the highest efficiency under the most probable operational situation. This is not to say however, that the proposed pumps will not operate properly when the other pumps are running, just that they won't likely be operating at their most efficient point. 2) That the proposed pumps would primarily be operated during off-peak times. This generally applies to minimum hour demand periods during the summer time when the elevated storage is not being re-filled, and during the wet months of late fail, winter and early spring. Using this assumption, a system-curve was develop for each design year utilizing the minimum hourly demand period data set. This data set was Mr. Howard Pafford City of Coppell June 12, 1995 Page No. 2 developed from the average day demand data contained in the Kimley-Horn Report and is roughly equivalent to 80% of the average day demand. Another reason for using the minimum hourly demand period as the basis of the system curve development is that during this period of the system operation the highest system heads are normally experienced. We have also made a preliminary pump selection based on the system curves we developed and on the information we were able to derive from the City's water system analysis report. Reviewing the output data from the hydraulic analysis of the distribution system, we found that for most operating conditions the proposed pumps were delivering in the range of 2,600 to 3,000 gallons per minute. This delivery rate was based on proposed pumps rated at 250 horsepower each. Using the delivery rate as a basis of pump selection, we reviewed several Worthington horizontal split case pumps and found the model 8LR-20 with a 17-inch impeller, or the model 10LR-14 with a 14.17-inch impeller, to be best suited for this application. Based on the system curves we developed and the Worthington pumps identified above, we recommend the either one (but not both) of the design requirements shown below be included in the pump specifications for this project: Village Parkway Pump Station Expansion Proposed Pumps No. 5 & 6 Operating Points Based on Design Year 1995 Worthington 8LR-20 Worthington 10LR-14 Minimum Rated I Maximum Minimum I Rated I Maximum Duty Point Duty Point Duty Point Duty Point Duty Point Duty Point Q (gpm) 3,100 3,500 3,700 2,000 2,700 4,200 Total Dynamic Head (ft) 217 200 184 220 210 185 Minimum Efficiency 80% 78% 76% 65% 78% 86% Pump Speed: 1,770 rpm 1,770 rpm Shutoff Head - Maximum 315 Ft. 260 Ft. Shutoff Head - Minimum 290 Ft. 240 Ft. Maximum BHP 250 Hp. 250 Hp. We have plotted both the Worthington, model 8LR-20 and model 10LR-14 pump curves on the system curve for each design year. The Worthington pumps were used as the basis for pump selection due to their existing service in the Village Parkway Pump Station, however many other pump manufactures have pumps that offer similar operating characteristics. We recommend the specifications for this project allow no less than three pump manufactures of equal experience, quality and service capabilities. Mr. Howard Pafford City of Coppeli June 12, 1995 Page No. 3 Please review the enclosed system-head curves and the operating points we have chosen as the basis of pump selection for this project and notify us of your findings. We are available to discuss this project further at your convenience. cc: Kenne~ M. Griffin, P.E. Shimek, Jacobs & Finklea City of Coppell, Texas Village Parkway Pump Station Additions Table No. 1 System - Head Curve Data (Minimum Hour Demand) Total Dynamic Head (FL) 1995 2004 2014 Q (gpm) Minimum Maximum Minimum Maximum Minimum Maximum 0 177.70 220.20 177.72 220.22 176.98 219.48 500 178.74 221.24 178.24 220.74 177.52 220.02 1,000 179.52 222.02 178.68 221.18 178.00 220.50 1,500 180.06 222.56 179.07 221.57 178.43 220.93 2,000 180.52 223.02 179.42 221.92 178.83 221.33 2,500 181.22 223.72 179.74 222.24 179.19 221.69 3,000 182.10 224.60 180.04 222.54 179.53 222.03 3,500 183.24 225.74 180.32 222.82 179.84 222.34 4,000 184.66 227.16 180.61 223.11 180.12 222.62 4,500 186.35 228.85 180.94 223.44 180.40 222.90 5,000 188.30 230.80 181.32 223.82 180.70 223.20 5,500 190.51 233.01 181.77 224.27 181.02 223.52 6,000 192.98 235.48 182.30 224.80 181.38 223.88 6,500 195.70 238.20 182.89 225.39 181.80 224.30 7,000 198.66 241.16 183.54 226.04 182.28 224.78 7,500 201.87 244.37 184.27 226.77 182.81 225.31 8,000 205.32 247.82 185.07 227.57 183.41 225.91 8,500 209.00 251.50 185.94 228.44 184.06 226.56 9,000 212.92 255.42 186.87 229.37 184.77 227.72 10,000 221.44 263.94 188.95 231.45 186.37 228.87 11,000 230.88 273.38 191.30 233.80 188.20 230.70 12,000 241.20 283.70 193.92 236.42 190.25 232.75 13,000 252.41 294.91 196.81 239.91 192.52 235.02 14,000 264.48 306.98 199.95 242.45 195.00 237.50 15,000 277.41 319.91 203.35 245.85 197.70 240.21 16,000 291.18 333.68 206.99 249.49 200.62 243.12 No~: D~a presented ~ this ruble was generated from K.Y. Pipe Computer Model provided by Kimerly -Horn & Associ~es and presented in thek report on the Wmer Distribution System Master Plan for the City of Coppell, Dated October, 1994. Shimek, Jacobs & Finklea City of Coppell, Texas Village Parkway Pump Station Additions Table No. 2 System - Head Curve Data (Maximum Hour Demand) Total Dynamic Head (Ft.) 1995 2004 2014 Q (gpm) Minimum Maximum Minimum Maximum Minimum Maximum 0 62.47 104.97 85.25 124.96 59.64 93.02 500 69.37 111.87 85.54 128.04 59.71 96.21 1,000 76.11 118.61 88.57 131.07 59.95 99.35 1,500 82.70 125.20 91.55 134.05 59.95 102.45 2,000 89.13 131.62 94.48 136.98 62.99 105.50 2,500 95.39 137.89 97.35 139.85 66.01 108.51 3,000 101.50 144.00 100.17 142.67 68.98 111.48 3,500 107.44 149.94 102.94 145.44 71.91 114.41 4,000 113.22 155.72 105.65 148.15 74.80 117.30 4,500 118.83 161.33 108.30 150.80 77.64 120.14 5,000 124.27 166.77 110.90 153.40 80.44 122.94 5,500 129.51 172.01 113.44 155.94 83.20 125.70 6,000 134.56 177.06 115.93 158.43 85.91 128.41 6,500 139.38 181.88 118.36 160.86 88.57 131.07 7,000 143.98 186.48 120.74 163.24 91.19 133.69 7,500 148.32 190.82 123.08 165.58 93.76 136.26 8,000 152.41 194.91 125.38 167.88 96.29 138.79 8,500 156.35 198.85 127.65 170.15 98.78 141.28 9,000 160.15 202.65 129.88 172.38 101.24 143.74 10,000 167.28 209.78 134.24 176.74 106.09 148.59 11,000 173.77 216.27 138.47 180.97 110.82 153.32 12,000 179.89 222.39 142.58 185.08 115.46 157.96 13,000 185.54 228.04 146.58 189.08 120.01 162.51 14,000 190.81 233.31 150.47 192.97 124.48 166.98 15,000 195.76 238.26 154.25 196.75 128.85 171.35 16,000 201.62 244.12 157.95 200.45 133.12 175.62 Note: Data presented in this table was generated from K.Y. Pipe Computer Model provided by Kimerly -Horn & Associates and presented in their report on the Water Distribution System Master Plan for the City of Coppell, Dated October, 1994. Shimek, Jacola & Finkin City of Coppell, Texas Village Parkway Pump Station Additions Table No. 3 - Pump Curve Data Proposed Pumps EXISTING PUMPS Worthington Fairbanks Morse Worthingtom Worthington Worthinlton 8LR-20 Pump, 17" lmpeller 2824C- 6", 15.75" Impellee 6LR-18S Pump, 16" !mpdler 10LR-14 Pump, 14.75" !mlnil~ 10LR-18, 16" lmpdl~r Operating at 1770 RPM Operating at 1785 RPM Operating at 1770 RPM Operating at 1770 RPM Operating at 1765 RPM Total Dynamic Head (~) Total Dynamic Head (~) Total Dynamic Head (~) Total Dynamic Head (it) Total Dynamic Head 0 ([pm) one pump two Dumps one pump two pumps one pump two pump~ one pump two pump, one pump two 0 305 305 280 280 260 260 250 250 282 282 500 300 302.5 275 277.5 259 259.5 238 244 276 279 1,000 290 300 270 275 255 259 232 238 270 276 1,500 280 295 260 272.5 250 257 228 235 265 273 2,000 267.5 290 240 270 240 255 224 232 260 270 2,500 250 285 212 265 220 252.5 215 230 255 265.7 3,000 230 280 176 260 190 250 208 228 250 265 3,500 200 273.75 250 150 245 198 226 245 262.5 4,000 160 267.5 240 240 189 224 240 260 4,500 258.75 226 230 178 219.5 235 257.5 5,000 250 212 220 165 215 230 255 5,500 240 194 205 151 2 i 1.5 225 252.5 6,000 230 176 190 208 216.5 250 6,500 215 170 203 206.5 247.5 7,000 200 i 50 198 195 245 7,500 180 193.5 182.5 242.5 8,000 160 189 169 240 8,500 150 237.5 9,000 130 235 10,000 230 I 1,000 225 12,000 216.5 13,000 206.5 14,000 195 15,000 182.5 16.000 169 ShimeL Js~s & lrmidea Village Parkway Pump Station: System - Pump Head Curves Year 1995 - Minimum Hourly Demand Condition 320 ! Propond Pump No, 5+6 Maximum Syatom 300 ~ , / " Curve - ~' / \ ~,, ,,,." 280-~ ....\,,~ ,,/- ,, 26o .......~~· /,/ ...~ ,, 240 ~ ....... · ~ /// ,, ... \ 220 ""'.. %' , ' ' ' \ "" · ' ' '' ' ' \] Minimum System Curv~ 200 k' ' ' '~~ [ ...... - .. -,.... ,,,~ ... ---. IS0 ........... ' ...... ~-..  .. Existing Pumps No. 1, 2 or 3 ~60 N " ~ '~ (450 HP) IProposed Pump N~ ~ or 6 140 (250 HP nd~) 120 ] 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 IS 16 Q-gym Shimek, Jac, obs & Finklea Village Parkway Pump Station: System - Pump Head Curves Year 2004 - Minimum Hourly Demand Condition 320 300 280 260 240 220 200 180 160 140 120 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Thousands Q - gpm Shimek, Jacob & Finklea . Village Parkway Pump Station: System - Pump Head Curves Year 2014 - Minimum Hourly Demand Condition 320 · Poposed Pump No. 5 + 6 250 '~'-.,,. · -, ....... ,,, \ 260 .... "' ~ · , ""°"' % ..... _--- 200 ~ ................ .......................... ..= ..... ~ \ Existing Pumps No. 1;~ or3 Proposed Pump N~ 5 or 6 \ ' (450 HP) 140 i (250 HP 0 I 2 3 4 5 6 7 8 9 10 11 12 13 14 IS 16 Q -$pm