自来水管道流量一览表

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住宅给水流量、管径计算表(V1.2)

DN100 10.62
1.3 102
DN125 16.72
1.3 128
DN150 23.27
1.3 151
洗脸盆坐便器
0.75
0.5
每个洁具当量/每户卫生生洁具的数量
浴缸 1.2
洗涤盆洗衣机
1
1
淋浴 0.75
净身盆 0.5
预留当量合计
0
（Ng）
2
2
0
1
1
2
0
0
6
人数
3.5 14 24.5 84 119 196 227.5 381.5 700
管径（MM) 控制流量（L/S）控制流速（M/S）计算内径（mm）
DN15 0.10 0.8 12.8
DN20 0.21 0.8 18.3
DN25 0.41 0.9
24
衬塑钢管控制参数
DN32 DN40
DN50
0.76 1.02
2.36
0.9
0.9
1.2
32.8
38
50
衬塑钢管水力计算表
DN65 3.98 1.2
使用说明：白色区域为表格计算值，含公式，不允许修改；橙色区域为控制参数，允许修改，但修改
会影响表格计算值；黄色区域为用户输入区，输入参数后表格会自动计算"总当量"，"最大小时用水量"， "U0"，"ac"，"U"，"设计秒流量"，"适宜管径"，"流速"。但是要注意：1）“适宜管径”根据“控制流速” （控制流量）及“设计秒流量”自动取值，调整“控制流速”会自动生成控制流量，相应的“适宜管径”取值也会发生变化；您也可以在“手工调整管径”中修改管径并获得相对应的流速；2）“计算流速”根据“计算内径”及“设计秒流量”计算得到，与规范给出对照表中数据相近，此表格仅适用于表格规定管材的水力计算，非规定管材需慎重使用；3）按规范当Ng达到某值（即超规范限定值)，Qg取“最大小时用水量L/S”为“ 设计秒流量”,即当Qg>40L/S,则以“最大小时用水量”为“设计秒流量”。

管道流量流速表

管径/流速/流量对照表管径（DN）0.4m/s 0.6m/s 0.8m/s 1.0m/s 1.2m/s 1.4m/s 1.6 m/s 1.8 m/s 2.0m/s 2.2m/s 2.4m/s 2.6m/s 2.8m/s 3.0m/s流速对应流量m3/h20 0.5 0.7 0.9 1.1 1.4 1.6 1.8 2.0 2.3 2.5 2.7 2.9 3.2 3.4 25 0.7 1.1 1.4 1.8 2.1 2.5 2.8 3.2 3.5 3.9 4.2 4.6 4.9 5.3 32 1.2 1.7 2.3 2.9 3.5 4.1 4.6 5.2 5.8 6.4 6.9 7.5 8.1 8.7 40 1.8 2.7 3.6 4.5 5.4 6.3 7.2 8.1 9.0 10.0 10.9 11.8 12.7 13.6 50 2.8 4.2 5.7 7.1 8.5 9.9 11.3 12.7 14.1 15.6 17.0 18.4 19.8 21.2 65 4.8 7.2 9.6 11.9 14.3 16.7 19.1 21.5 23.9 26.3 28.7 31.1 33.4 35.8 80 7.2 10.9 14.5 18.1 21.7 25.3 29.0 32.6 36.2 39.8 43.4 47.0 50.7 54.3 100 11.3 17.0 22.6 28.3 33.9 39.6 45.2 50.9 56.5 62.2 67.9 73.5 79.2 84.8 125 17.7 26.5 35.3 44.2 53.0 61.9 70.7 79.5 88.4 97.2 106.0 114.9 123.7 132.5 150 25.4 38.2 50.9 63.6 76.3 89.1 101.8 114.5 127.2 140.0 152.7 165.4 178.1 190.9 200 45.2 67.9 90.5 113.1 135.7 158.3 181.0 208.6 226.2 248.8 271.4 294.1 316.7 339.3250 70.7 106.0 141.4 176.7 212.1 247.4 282.7 318.1 353.4 388.8 424.1 489.5 494.8 530.1 300 101.8 152.7 208.6 254.5 305.4 386.3 407.1 488.0 508.9 589.8 640.7 661.6 712.5 763.4 350 138.5 207.8 277.1 346.4 415.6 484.9 554.2 623.4 692.7 762.0 831.3 900.5 989.8 1089. 400 181.0 271.4 381.9 462.4 542.9 633.3 723.8 814.3 904.8 995.3 1085.1176.1286.1357.管径流速推荐值m/s：（DN）20 25 32 40 50 65 80 100 125 150 200 250 300 350 400闭式系统0.5-0.6 0.6-0.7 0.7-0.9 0.8-1 0.9-1.2 1.1-1.4 1.2-1.6 1.3-1.8 1.5-2.0 1.6-2.2 1.8-2.5 1.8-2.6 1.9-2.9 1.6-2.5 1.8-2.6 开式系统0.4-0.5 0.5-0.6 0.6-0.8 0.7-0.9 0.8-1.0 0.9-1.2 1.1-1.4 1.2-1.6 1.4-1.8 1.5-2.0 1.6-2.3 1.7-2.4 1.7-2.4 1.6-2.1 1.8-2.32 管道内流体常用流速范围和一般工程设计中的压力降控制值2.1 管道内各种介质常用流速范围管道内各种介质常用流速范围见表2.1。

水系统管径流速流量对照表

管径流量流速0.10.110.180.290.450.71 1.19 1.81 2.83 4.42 6.3611.3117.6725.4534.6445.2457.2670.69101.790.20.230.350.580.90 1.41 2.39 3.62 5.658.8412.7222.6235.3450.8969.2790.48114.51141.37203.580.30.340.530.87 1.36 2.12 3.58 5.438.4813.2519.0933.9353.0176.34103.91135.72171.77212.06305.360.40.450.71 1.16 1.81 2.83 4.787.2411.3117.6725.4545.2470.69101.79138.54180.96229.02282.74407.150.50.570.88 1.45 2.26 3.53 5.979.0514.1422.0931.8156.5588.36127.23173.18226.19286.28353.43508.940.60.68 1.06 1.74 2.71 4.247.1710.8616.9626.5138.1767.86106.03152.68207.82271.43343.53424.12610.730.70.79 1.24 2.03 3.17 4.958.3612.6719.7930.9344.5379.17123.70178.13242.45316.67400.79494.80712.510.80.90 1.41 2.32 3.62 5.659.5614.4822.6235.3450.8990.48141.37203.58277.09361.91458.04565.49814.300.9 1.02 1.59 2.61 4.07 6.3610.7516.2925.4539.7657.26101.79159.04229.02311.72407.15515.30636.17916.091 1.13 1.77 2.90 4.527.0711.9518.1028.2744.1863.62113.09176.71254.47346.36452.39572.56706.861017.881.1 1.24 1.94 3.18 4.987.7813.1419.9131.1048.6069.98124.41194.39279.92381.00497.63629.81777.541119.661.2 1.36 2.12 3.47 5.438.4814.3421.7133.9353.0176.34135.72212.06305.36415.63542.87687.07848.231221.451.30 1.47 2.30 3.76 5.889.1915.5323.5236.7657.4382.70147.03229.73330.81450.27588.11744.32918.921323.241.40 1.58 2.47 4.05 6.339.9016.7225.3339.5861.8589.06158.34247.40356.26484.90633.35801.58989.601425.031.50 1.70 2.65 4.34 6.7910.6017.9227.1442.4166.2795.43169.65265.07381.70519.54678.58858.831060.291526.811.60 1.81 2.83 4.637.2411.3119.1128.9545.2470.69101.79180.96282.74407.15554.18723.82916.091130.971628.601.70 1.92 3.00 4.927.6912.0220.3130.7648.0775.10108.15192.27300.41432.60588.81769.06973.341201.661730.391.80 2.04 3.18 5.218.1412.7221.5032.5750.8979.52114.51203.58318.09458.04623.45814.301030.601272.351832.181.90 2.15 3.36 5.508.6013.4322.7034.3853.7283.94120.87214.88335.76483.49658.09859.541087.851343.031933.962.00 2.26 3.53 5.799.0514.1423.8936.1956.5588.36127.23226.19353.43508.94692.72904.781145.111413.722035.752.10 2.38 3.71 6.089.5014.8425.0938.0059.3892.78133.60237.50371.10534.38727.36950.021202.371484.402137.542.20 2.49 3.89 6.379.9515.5526.2839.8162.2097.19139.96248.81388.77559.83761.99995.261259.621555.092239.332.30 2.60 4.06 6.6610.4016.2627.4841.6265.03101.61146.32260.12406.44585.28796.631040.501316.881625.772341.112.402.714.246.9510.8616.9628.6743.4367.86106.03152.68271.43424.12610.73831.271085.731374.131696.462442.905006004004503003502501501006532402025管径/流速/流量对照表1 青岛奥特斯机电系统工程有限公司管径单位：DN 流速单位：m/s 流量单位：m 3/h 圆周率（π）：3.1415926管道管径规格大小（DN）5080125200管径流量流速2.50 2.83 4.427.2411.3117.6729.8645.2470.69110.45159.04282.74441.79636.17865.901130.971431.391767.152544.692.60 2.94 4.597.5311.7618.3831.0647.0573.51114.86165.40294.05459.46661.62900.541176.211488.641837.832646.482.70 3.05 4.777.8212.2119.0932.2548.8676.34119.28171.77305.36477.13687.07935.171221.451545.901908.522748.272.80 3.17 4.958.1112.6719.7933.4550.6779.17123.70178.13316.67494.80712.51969.811266.691603.151979.202850.052.90 3.28 5.128.4013.1220.5034.6452.4882.00128.12184.49327.98512.47737.961004.451311.931660.412049.892951.843.00 3.39 5.308.6913.5721.2135.8454.2984.82132.54190.85339.29530.14763.411039.081357.171717.672120.583053.633.1 3.51 5.488.9814.0221.9137.0356.1087.65136.95197.21350.60547.82788.851073.721402.411774.922191.263155.423.2 3.62 5.659.2614.4822.6238.2357.9190.48141.37203.58361.91565.49814.301108.351447.651832.182261.953257.203.3 3.73 5.839.5514.9323.3339.4259.7293.31145.79209.94373.22583.16839.751142.991492.881889.432332.633358.993.4 3.85 6.019.8415.3824.0340.6261.5296.13150.21216.30384.53600.83865.191177.631538.121946.692403.323460.783.5 3.96 6.1910.1315.8324.7441.8163.3398.96154.63222.66395.84618.50890.641212.261583.362003.942474.003562.573.6 4.07 6.3610.4216.2925.4543.0165.14101.79159.04229.02407.15636.17916.091246.901628.602061.202544.693664.353.7 4.18 6.5410.7116.7426.1544.2066.95104.62163.46235.38418.46653.84941.541281.531673.842118.452615.383766.143.8 4.30 6.7211.0017.1926.8645.3968.76107.44167.88241.75429.77671.52966.981316.171719.082175.712686.063867.933.9 4.41 6.8911.2917.6427.5746.5970.57110.27172.30248.11441.08689.19992.431350.811764.322232.972756.753969.724 4.527.0711.5818.1028.2747.7872.38113.10176.71254.47452.39706.861017.881385.441809.562290.222827.434071.504.1 4.647.2511.8718.5528.9848.9874.19115.92181.13260.83463.70724.531043.321420.081854.802347.482898.124173.294.2 4.757.4212.1619.0029.6950.1776.00118.75185.55267.19475.01742.201068.771454.711900.042404.732968.814275.084.3 4.867.6012.4519.4530.3951.3777.81121.58189.97273.55486.32759.871094.221489.351945.272461.993039.494376.874.4 4.987.7812.7419.9131.1052.5679.62124.41194.39279.92497.63777.541119.661523.991990.512519.243110.184478.654.5 5.097.9513.0320.3631.8153.7681.43127.23198.80286.28508.94795.221145.111558.622035.752576.503180.864580.444.6 5.208.1313.3220.8132.5254.9583.24130.06203.22292.64520.25812.891170.561593.262080.992633.753251.554682.234.7 5.328.3113.6121.2633.2256.1585.05132.89207.64299.00531.56830.561196.001627.892126.232691.013322.234784.024.85.438.4813.9021.7133.9357.3486.86135.72212.06305.36542.87848.231221.451662.532171.472748.273392.924885.8050060040045030035020025015080100125506532402025管径/流速/流量对照表2 青岛奥特斯机电系统工程有限公司管径单位：DN 流速单位：m/s 流量单位：m 3/h 圆周率（π）：3.1415926管道管径规格大小（DN）管径流量流速4.95.548.6614.1922.1734.6458.5388.67138.54216.48311.72554.18865.901246.901697.172216.712805.523463.614987.595 5.658.8414.4822.6235.3459.7390.48141.37220.89318.09565.49883.571272.351731.802261.952862.783534.295089.385.1 5.779.0114.7723.0736.0560.9292.29144.20225.31324.45576.80901.241297.791766.442307.192920.033604.985191.175.2 5.889.1915.0623.5236.7662.1294.10147.03229.73330.81588.11918.921323.241801.082352.422977.293675.665292.965.3 5.999.3715.3523.9837.4663.3195.91149.85234.15337.17599.42936.591348.691835.712397.663034.543746.355394.745.4 6.119.5415.6324.4338.1764.5197.72152.68238.56343.53610.73954.261374.131870.352442.903091.803817.045496.535.5 6.229.7215.9224.8838.8865.7099.53155.51242.98349.89622.04971.931399.581904.982488.143149.053887.725598.325.6 6.339.9016.2125.3339.5866.90101.34158.34247.40356.26633.35989.601425.031939.622533.383206.313958.415700.115.7 6.4510.0716.5025.7940.2968.09103.14161.16251.82362.62644.651007.271450.471974.262578.623263.564029.095801.895.8 6.5610.2516.7926.2441.0069.29104.95163.99256.24368.98655.961024.941475.922008.892623.863320.824099.785903.685.9 6.6710.4317.0826.6941.7070.48106.76166.82260.65375.34667.271042.621501.372043.532669.103378.084170.466005.476 6.7910.6017.3727.1442.4171.68108.57169.65265.07381.70678.581060.291526.812078.162714.343435.334241.156107.266.1 6.9010.7817.6627.6043.1272.87110.38172.47269.49388.07689.891077.961552.262112.802759.573492.594311.846209.046.27.0110.9617.9528.0543.8374.06112.19175.30273.91394.43701.201095.631577.712147.442804.813549.844382.526310.836.37.1311.1318.2428.5044.5375.26114.00178.13278.33400.79712.511113.301603.152182.072850.053607.104453.216412.626.47.2411.3118.5328.9545.2476.45115.81180.96282.74407.15723.821130.971628.602216.712895.293664.354523.896514.416.57.3511.4918.8229.4145.9577.65117.62183.78287.16413.51735.131148.641654.052251.342940.533721.614594.586616.196.67.4611.6619.1129.8646.6578.84119.43186.61291.58419.87746.441166.321679.502285.982985.773778.864665.276717.986.77.5811.8419.4030.3147.3680.04121.24189.44296.00426.24757.751183.991704.942320.623031.013836.124735.956819.776.87.6912.0219.6930.7648.0781.23123.05192.27300.41432.60769.061201.661730.392355.253076.253893.384806.646921.566.97.8012.1919.9831.2148.7782.43124.86195.09304.83438.96780.371219.331755.842389.893121.493950.634877.327023.3477.9212.3720.2731.6749.4883.62126.67197.92309.25445.32791.681237.001781.282424.523166.734007.894948.017125.137.18.0312.5520.5632.1250.1984.82128.48200.75313.67451.68802.991254.671806.732459.163211.964065.145018.697226.927.28.1412.7220.8532.5750.8986.01130.29203.58318.09458.04814.301272.351832.182493.803257.204122.405089.387328.71500600400450300350200250125150801005065管径单位：DN 流速单位：m/s 流量单位：m 3/h 圆周率（π）：3.1415926管道管径规格大小（DN）3240管径/流速/流量对照表3 青岛奥特斯机电系统工程有限公司2025管径流量流速7.38.2612.9021.1433.0251.6087.21132.10206.40322.50464.41825.611290.021857.622528.433302.444179.655160.077430.497.48.3713.0821.4333.4852.3188.40133.91209.23326.92470.77836.921307.691883.072563.073347.684236.915230.757532.287.58.4813.2521.7133.9353.0189.59135.72212.06331.34477.13848.231325.361908.522597.703392.924294.165301.447634.077.68.6013.4322.0034.3853.7290.79137.53214.88335.76483.49859.541343.031933.962632.343438.164351.425372.127735.867.78.7113.6122.2934.8354.4391.98139.34217.71340.18489.85870.851360.701959.412666.983483.404408.685442.817837.657.88.8213.7822.5835.2955.1393.18141.15220.54344.59496.21882.161378.371984.862701.613528.644465.935513.507939.437.98.9313.9622.8735.7455.8494.37142.96223.37349.01502.58893.471396.052010.312736.253573.884523.195584.188041.2289.0514.1423.1636.1956.5595.57144.76226.19353.43508.94904.781413.722035.752770.883619.114580.445654.878143.018.19.1614.3123.4536.6457.2696.76146.57229.02357.85515.30916.091431.392061.202805.523664.354637.705725.558244.808.29.2714.4923.7437.1057.9697.96148.38231.85362.26521.66927.401449.062086.652840.163709.594694.955796.248346.588.39.3914.6724.0337.5558.6799.15150.19234.68366.68528.02938.711466.732112.092874.793754.834752.215866.928448.378.49.5014.8424.3238.0059.38100.35152.00237.50371.10534.38950.021484.402137.542909.433800.074809.465937.618550.168.59.6115.0224.6138.4560.08101.54153.81240.33375.52540.75961.331502.072162.992944.063845.314866.726008.308651.958.69.7315.2024.9038.9160.79102.73155.62243.16379.94547.11972.641519.752188.432978.703890.554923.986078.988753.738.79.8415.3725.1939.3661.50103.93157.43245.99384.35553.47983.951537.422213.883013.343935.794981.236149.678855.528.89.9515.5525.4839.8162.20105.12159.24248.81388.77559.83995.261555.092239.333047.973981.035038.496220.358957.318.910.0715.7325.7740.2662.91106.32161.05251.64393.19566.191006.571572.762264.773082.614026.275095.746291.049059.10910.1815.9026.0640.7263.62107.51162.86254.47397.61572.561017.881590.432290.223117.254071.505153.006361.739160.889.110.2916.0826.3541.1764.32108.71164.67257.30402.03578.921029.191608.102315.673151.884116.745210.256432.419262.679.210.4016.2626.6441.6265.03109.90166.48260.12406.44585.281040.501625.772341.113186.524161.985267.516503.109364.469.310.5216.4326.9342.0765.74111.10168.29262.95410.86591.641051.811643.452366.563221.154207.225324.766573.789466.259.410.6316.6127.2242.5266.44112.29170.10265.78415.28598.001063.111661.122392.013255.794252.465382.026644.479568.039.510.7416.7927.5142.9867.15113.49171.91268.61419.70604.361074.421678.792417.463290.434297.705439.276715.159669.829.610.8616.9627.7943.4367.86114.68173.72271.43424.12610.731085.731696.462442.903325.064342.945496.536785.849771.619.710.9717.1428.0843.8868.57115.88175.53274.26428.53617.091097.041714.132468.353359.704388.185553.796856.539873.409.811.0817.3228.3744.3369.27117.07177.34277.09432.95623.451108.351731.802493.803394.334433.425611.046927.219975.189.911.2017.4928.6644.7969.98118.26179.15279.92437.37629.811119.661749.472519.243428.974478.655668.306997.9010077.01011.3117.6728.9545.2470.69119.46180.96282.74441.79636.171130.971767.152544.693463.614523.895725.557068.5810178.820253240506580100125150200250300350400闭式系统0.5-0.60.6-0.70.7-0.90.8-10.9-1.2 1.1-1.4 1.2-1.6 1.3-1.8 1.5-2.0 1.6-2.2 1.8-2.5 1.8-2.6 1.9-2.9 1.6-2.5 1.8-2.6开式系统0.4-0.50.5-0.60.6-0.80.7-0.90.8-1.00.9-1.2 1.1-1.4 1.2-1.6 1.4-1.8 1.5-2.01.6-2.31.7-2.41.7-2.41.6-2.11.8-2.350060040045030035020025012515080100管径单位：DN 流速单位：m/s 流量单位：m 3/h 圆周率（π）：3.1415926管道管径规格大小（DN）5065管径/流速/流量对照表4 青岛奥特斯机电系统工程有限公司253240管径流速推荐安全值流速推荐值m/s:20管径(DN)。

住宅给水流量、管径计算表(hw)

23 0.5
11.50
0 0
0.00
同时出流设计秒流最大理论手工调整调整后流理论管径计算流速概率流速管径量取值 DN（mm）速(m/s) DN（mm） (m/s) (m/s) （mm） Qg(L/S) U(%) 2.79 1.5 50 1.42 50 1.42 9.77
给水塑料管) 同时出流设计秒流最大理论手工调整调整后流理论管径计算流速概率流速管径量取值 DN（mm）速(m/s) (m/s) DN（mm） (m/s) （mm） Qg(L/S) U(%) 2.79 1.5 50 1.42 50 1.42 9.77
流量与管径对应值：0-0.16L/S——DN15；0.16-0.30L/S——DN20；0.30-0.60L/S——DN25；0.60-1.1L/S——DN 3.0L/S——DN50；3.0-5.0L/S——DN70；5.0-8.5L/S——DN80；8.5-14L/S——DN100；3）塑料管流量与管径对应值 0.20-0.30L/S——DN20；0.30-0.60L/S——DN25；0.60-1.0L/S——DN32；1.0-2.0L/S——DN40；2.0-3.5L/S——DN 5.5-9.5L/S——DN80；9.5-14L/S——DN100；
q g = 0.2 × U × N g , U =
固 qg = 0.2 N g + 0.2 N g × α c × ( N g − 1)0.49
qg——计卫生器具给水当量总数。0.2—— 量。αc——对应于不同的卫生器具的给水当量平均出流概率
每户卫生生洁具的数量洗涤盆 1 洗衣机 1 淋浴 1 净身盆 1 预留 0
）
住宅当量计算表

某些流体在管道中的常用流速范围

蛇管、螺旋管内的冷却水
＜1.0
低压空气
12~15
高压空气
15~25
一般气体（常压）
10~20
鼓风机吸入管
10~15
鼓风机排出管
15~20
离心泵吸入管（水一类液体）
1.5~2.0
离心泵排出管（水一类液体）
2.5~30
往复泵吸入管（水一类液体）
0.75~1.0
往复泵排出管（水一类液体）
1.0~2.0
液体自流速度（冷凝水等）
176.625
0.049
DN800
1808.64
0.5024
DN50
7.065
0.00196
DN300
254.34
0.07065
DN900
2289.06
0.63585
DN65
11.94
0.00332
DN350
346.185
0.0961
DN1000
2826
0.785
DN80
18
0.00502
DN400
0.5
真空操作下气体流速
＜10
管道流量表：
管径
流量M3/小时（按1米/秒计算）
截面积M2
管径
流量M3（按1米/秒计算）
截面积M2
管径
流量M3/小时（按1米/秒计算）
截面积M2
DN15
0.636
0.0001766
DN100
28.26
0.00785
DN450
572.265
0.159
DN20
1.13
0.000314
DN125
44.16
0.0122

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自来水管道流量一览表
市政给水管管径
市政给水管管径，一般用PE，口径从20mm -620mm 。

一般是按水泵出口口径选配水管的管径；水泵连接的出水管不是管径越大越好，选的管径能满足流量的要求而且阻力损失又合理时为好。

是按计算的,15mm=4分管,20mm=6分,25mm=1寸;/ 则是按计算的,16mm也就相当于3分管,20mm差不多相当于4分的。

径
一般工程上计算时，水管路，压力常见为0.1--0.6MPa，水在水管中流速在1--3米/秒，常取1.5米/秒。

流量=管截面积X流速=0.002827X管径^2X流速(立方米/小时)^2：平方。

管径单位：mm 管径=sqrt(353.68X流量/流速)；sqrt：开平方；的公式与水相同，只是流速一般取20--40米/秒。

水流量计算表
DN15、DN25、DN50管道的流量各为多少？DN15、DN25、DN50管径的截面积分别为：DN15： 152*3.14/4=176.625平方毫米，合0.0177平方分米。

DN25： 252*3.14/4=490.625平方毫米，合0.0491平方分米。

DN50： 502*3.14/4=1962.5平方毫米，合0.1963平方分米。

设管道流速为V=4米/秒，即V=40分米/秒，且1升=1立方分米，则管道的流量分别为（截面积乘以流速）：
DN15管道：流量Q=0.0177*40=0.708升/秒，合2.55立方米/小时。

DN25管道：流量Q=0.0491*40=1.964升/秒，合7.07立方米/小时。

DN50管道：流量Q=0.1963*40=7.852升/秒，合28.27立方米/小时。

注：必须给定流速才能计算流量，上述是按照4米/秒计算的。

管径与流速、流量的计算方法一般工程上计算时，水管路，压力常见为0.1--0.6MPa，水在水管中流速在1～3米/秒，常取1.5米/秒。

流量=管截面积×流速=0.002827×管径^2×流速 (立方米/小时)
水压在0.2mpa，流量是15立方每小时，要用的管径是多少0.2Mpa的水压全部转换为动能，速度为20m/s，体积流量为15m^3/h，可换算为0.0042m^3/s，则管道面积为：
0.0042/20=0.00021m^2=210mm^2，管路直径为16.3mm，考虑到压力损失，选择20mm的管路就差不多了流量=流速流通面积。

而根据管道水流量计算公式Q=（H/sL）1/2流量与管道长度存在关系，请问怎么理解？流量=流速过流面积根据管道水流量计算公式
Q=VXSV---液体流动的流速S---过流断面的面积L---是流量的单位为每秒升流量与管道长度不存在关系。

它指的是单位时间内通过某一断面液体的数量，与长度没有关系。