电热设计资料(自整理)

1、计量单位1.功率： w、 kw1kw=3.412btu/hr(英热单位 / 小时 )=1.36( 马力 )=864kcal/hr2.重量： kg1kg=2.204621b( 磅 )3. 流速： m/min4. 流量： m3/min、kg/ho5. 比热： kcal/(kg ) 1kcal/(kg)=1btu/hr. f=4186.8j/(kg )21w/c =6.4516 w/in26. 功率密度： w/cm7. 压力： mpa8. 导热系数： w/(m) 1 w/(m)=0.01j/(cm s )=0.578btu/(ft.h.f)9. 温度：1of=9/5 321r=9/5 491.671

2、k=1 273.15电加热功率计算加热功率的计算有以下三个方面：运行时的功率启动时的功率系统中的热损失所有的计算应以最恶劣的情况考虑：最低的环境温度最短的运行周期最高的运行温度加热介质的最大重量（流动介质则为最大流量）设计电加热器系统的步骤根据工艺过程，画出加热的工艺流程图（不涉及材料形式及规格）。计算工艺过程所需的热量。计算系统起动时所需的热量及时间。重画加热工艺流程图，考虑合适的安全系数，确定加热器的总功率。1决定发热元件的护套材料及功率密度。决定加热器的形式尺寸及数量。决定加热器的电源及控制系统。有关加热功率在理想状态下的计算公式如下：系统起动时所需要的功率：系统运行时所需要的功率：加热

3、系统的散热量管道平面式中符号，含义如下：p功率： kwq2散热量：管道为 w/m；平面为 w/mm1介质重量： kg保温材料的导热数： w/mkc1介质比热： kcal/kg 保温材料厚度： mmm2容器重量： kgd管道外径： mmc2介质比热： kcal/kg l管道长度： mm3每小时增加的介质重量或流s2系统的散热面积： m量 :kg/hc3介质比热： kcal/kg t 介质和环境温度之差或温升：h 加热时间： h有关加热功率计算的参考数据（如需更多数据，请来电、来函咨询）2各种物质的比热（ 25） cal/(g ) kcal/(kg)物质比热物质比热物质比热物质比热氢气3.41乙醇

4、0.55导热油0.46玻璃0.200水1.00丙醇0.67二氧化碳0.24银0.056冰0.50丁醇0.69氨0.52锡0.051酒精0.58丙酮0.51空气0.24汞0.033甘油0.58石油0.52软木塞0.49锌0.090乙醚0.56石蜡0.77沥青0.40铝0.215煤油0.51蜂蜡0.82硬橡胶0.34炉渣0.180机油0.40醋酸0.42abs塑料0.35镍0.106松香水0.42硫磺0.24陶瓷0.26钢0.120氮气0.25硫酸0.34混凝土0.21生铁0.130苯0.34橄榄油0.47岩盐0.22铁0.118甲苯0.44蓖麻油0.43无定形碳0.17黄铜0.090萘0.40天

5、然气0.60硫0.18铜0.092甲醇0.60氯化氢0.20水泥0.19石墨0.174各种气体和蒸汽的定容定压比热cal/(g ) kcal/(kg)物质温度（）定压比热（ cp）定容比热（ cv）氢163.412.42氦181.250.75氨200.510.39水蒸汽100-3000.470.36酒精蒸汽108-2200.450.40乙醚蒸汽25-1110.430.40氮200.250.18一氧化碳180.250.18空气20-1000.240.17氧200.220.16二氧化碳200.200.15氯化氢22-2140.190.13各种物质的密度物质比重物质比重物质比重气体（ 0和标准大气压

6、下，g/cm3）氢0.00009甲烷0.00078氦0.00018乙炔0.00117氖0.00090一氧化碳0.00125氮0.00125空气0.00129氧0.00143一氧化氮0.00134氟0.001696硫化氢0.001543氩0.00178二氧化碳0.00198臭氧0.00214二氧化氮0.00198氯0.00321氰0.00234氪0.00374二氧化硫0.00293氙0.00589溴化氢0.00364氡0.00973碘化氢0.00579煤气0.00060氨0.0007液体（常温 g/cm3）汽油0.70橄榄油0.92硝酸1.50乙醚0.71鱼肝油0.95硫酸1.80石油0.76蓖

7、麻油0.97溴3.12酒精0.79纯水1.00水银14.20木精0.80海水1.03煤油0.80醋酸1.05松节油0.86盐酸1.20苯0.88无水甘油1.26矿油0.9-0.93二硫化碳1.29植物油0.9-0.93蜂蜜1.40固体（常温 g/cm 3）铸钢7.80铅11.34有机玻璃1.18碳钢7.80-7.85镁1.738石灰石2.60-3.0铸铁6.80-7.20锌7.133沥青0.90-1.50铝2.70铬7.19白磷1.82银10.49锰7.43碳1.90-2.30金19.302钠0.97铜8.93钨19.254康铜8.90钽16.60镍8.90锡5.765镍铬8.40铂21.45

8、各种物质的溶点溶解热沸点和汽化热物质溶点 ( )溶解热（ cal/g ）沸点（）汽化热（ cal/g ）乙醚-11723.543584酒精-11423.5478204二硫化碳-11245.346.2584冰080100539各种保温材料的导热系数和最高使用温度材料最高使用温度（）常温下的导热系数（ w/mk）4玻璃纤维3000.036岩棉3500.044矿渣棉3500.040膨涨珍珠岩5500.047聚氨脂泡沫塑料800.024聚苯稀泡沫塑料600.031硅酸钙5500.054复合硅酸盐毡 fhp-vb7000.024复合硅酸盐 fhp-v涂料7000.024硅酸铝（干法制造）4000.046

9、硅酸铝（湿法制造）8000.046注：准确的数据请查供应商的说明书不同温度下，不同管径的保温材料的厚度材料：岩棉外表封皮：铝或不锈钢湿度： 81%环境温度：15.4 风速： 3.8m/s管道直径管道温度（）英寸 / 公称直径 / 毫米 25 5075100 125 150 175 200 225 250 275 300 325 350 375 400 425 4501/2 /15/21.3425 303030405050506060608080 80 80 80 80 803/4 /20/26.6725 303040405050606060708080 80 80 80 80 801/25/3

10、3.4025 304040405060606070708080 80 80 80 80 801/2 /40/48.2625 304040505060607070709090 90 90 90 90 902/50/60.3330 404050506060707070709090 100 100 100 120 1203/80/88.9030 4040505060707070808090110 110 120 130 130 1504/100/1140330 40505050607080809090100 100 110 120 130 130 1606/150/168.330 405060707

11、08080100 100 100 110 130 130 130 130 160 1608/200/219.140 50506070808090100 100 100 110 130 130 130 150 170 18010/250/273.140 506060708080 100 100 100 120 120 140 140 170 170 180 19012/300/323.940 506060708080 100 100 100 120 140 140 170 170 180 190 20014/350/355.640 606060708080 100 100 100 140 140

12、 170 170 180 190 200 20016/400/406.440 606080808090 100 100 100 140 150 170 180 180 190 200 21018/450/457.240 606080809090 100 100 110 150 160 170 180 180 190 22 21020/500/508.060 6060809090 100 100 100 120 160 160 180 190 200 210 220 22024/600/609.6060 6060809090 100 100 100 120 170 170 190 200 200

13、 210 220 22026/650/660.4060 6060100 10090 100 130 130 140 200 200 200 200 200 210 220 22028/700/711.2060 6070100 10090 110 130 130 140 200 200 200 200 200 210 220 22030/750/762.060 6070100 100 100 110 130 130 170 200 200 200 200 200 210 220 28036/900/91404070 7090100 100 100 110 160 170 180 200 200

14、200 200 200 210 220 28040/1000/1016.070 7090100 100 100 110 170 180 190 200 200 200 200 200 280 280 290542/1050/1066.8070 70 90 100 100 100 110 170 180 190 200 200 200 200 280 280 290 30048/1200/1219.2070 70 90 100 100 100 110 170 190 190 200 200 200 200 290 300 300 30054/1350/1371.6070 70 100 100 1

15、00 100 150 180 190 190 200 200 200 280 300 300 300 30060/1500/1524.0070 70 100 100 100 100 160 180 200 200 200 200 280 280 300 300 300 30066/1650/1676.8070 70 100 100 100 100 170 190 200 200 200 200 280 300 300 300 300 30072/1800/1828.8070 80 100 100 100 100 170 190 200 200 200 200 280 300 300 300 3

16、00 300罐体 70 100 100 100 100 180 200 200 200 300 300 300 300 300 300 300 400 400 以上数据仅供参考常用的设计图表在工程的计算和电加热器的选型中，经常要涉及到一些常用数据，如介质表面的热损失、介质在不同工况下的温度变化等。为了防止在电加热器工作的同时，对介质的性能和加热元件产生不必要的损伤，下面列出了部分图表，供选型参考。1.强迫对流下加热器功率密度的选择（空气，环境温度20）出口温度出口流速 m/min2. 水表面的热损失（环境温度 20）热损失 kw/m26表面温度3. 油或蜡表面的热损失（环境温度 20）2热损失

17、 kw/m表面温度4.溶融金属表面的热损失（铝、巴氏合金、锡，环境温度20）2热损失 kw/m7表面温度5. 陶瓷纤维绝热层表面的热损失（ 64kg/m3, 环境温度 20）2热损失 kw/m表面温度6. 未保温的钢表面的热损失（环境温度 20）2热损失 kw/m8表面温度7. 自然对流下环境温度和管表面温度的变化曲线（ 12 管径）管表面温度出口流速 m/minthe document of electric heatingcomputation unit1.wattage ：w 、kw1kw=3.412btu/hr=1.36(hp)=864kcal/hr92.weight ：kg1kg=2

18、.204621b3.flow rate ：m/min4.flux ：m3/min 、kg/h5.specific heat ：kcal/(kg )1kcal/(kg )=1btu/hr. o f=4186.8j/(kg )6.wattage density ：w/cm 21w/c =6.4516 w/in 27.pressure ：mpa8.heat conductivity ： w/(m )1 w/(m )=0.01j/(cm s )=0.578btu/(ft.h.f)9.temp. ：1of=9/5 321r=9/5 491.671k=1 273.15calculating the hea

19、ter wattagecalculation of the heating wattage refers to the following three point：wattage for workingwattagefor startupsystem heat lossall the calculation should be under the worst condition：the lowest ambient temp.max process temp.the shortest process cyclemax weight for heating medium (as for flow

20、ing medium ,it is the max flux)the step for designing the heater system：according to the craftwork process, draw the technical flow chart of the heater. (it doesnt contain material and specification)calculating the needed energy for the craftworkcalculating the needed energy and time while the syste

21、m startupre-draw technical flow chart, and consider the right safety factor, and confirm the total wattage for the heater.10confirming the jacket material for the hating component and wattage density.confirming the size and amount for the heaterconfirming the power supply and control system for the

22、heaterthe calculation for heating power under the ideal condition：wattage for system opening：wattage for system working：quantity of heat dissipation for heating systemtubeplanemeaning of symbol for ceremony：pwattage ：kw；planew/m 2qquantity of heat dissipation : tube w/mm1medium weight ：kgc1medium sp

23、ecific heat: kcal/kgm2container weight: kgc2container specific heat: kcal/kg m3adding the weight and flux for medium per hour: kg/hc3medium specific heat: kcal/kg t temp. defference between the medium and environment or temperature rise：hheating hours ：hheating quotiety for heat-insulating material

24、：w/mkthickness for heat-insulating material：mmd tube outer dia. ：mm l tube length ：ms area for heat dissipation ：m211the reference data for calculating the heating wattage（if needs more, pls connectus ）specific heat for kinds of material （ 25） cal/(g ) kcal/(kg )specificmaterialspecificspecificmater

25、ial比热materialheatheatmaterialheathydrogen3.41ethanol0.55heat0.46glass0.200conducting oilwater1.00propanol0.67carbon0.24silver0.056bisulfideice0.50butanol0.69ammonia0.52tin0.051alcohol0.58acet.0.51air0.24hg0.033glycerin0.58petroleum0.52cork0.49zinc0.090aether0.56olefin0.77asphaltum0.40aluminium0.215c

26、oal oil0.51beeswax0.82ebonite0.34slag0.180machine oil0.40vinegar0.42abs plastic0.35nickel0.106colophony0.42sulfur0.24china0.26steel0.120nitrogen0.25vitriol0.34concrete0.21pig iron0.130benzene0.34olive oil0.47halite0.22iron0.118toluene0.44castor oil0.43amorphism0.17brass0.090carbon0.40natural0.60sulf

27、ur0.18copper0.092naphthalenegascarbinol0.60hcl0.20cement0.19graphite0.174specific heat at constant pressure and volume for kinds of gas and steam cal/(g)kcal/(kg )specific heatspecific heatmaterialtemp. （）at constantat constantpressure （cp ）volume （cv ）hydrogen163.412.42helium181.250.75ammonia200.51

28、0.39water vapour100-3000.470.36alcohol vapour108-2200.450.40aether vapour25-1110.430.40nitrogen200.250.18carbon monoxide180.250.18air20-1000.240.1712oxygen200.220.16co 2200.200.15hcl22-2140.190.13density for each kind of materialmaterialproportionmaterialproportionmaterialproportiongas （ 0 and under

29、 satandard atomospherepressure g/cm 3）hydrogen0.00009firedamp0.00078helium0.00018acetylene0.00117neon0.00090carbon monoxide0.00125nitrogen0.00125air0.00129oxygen0.00143no0.00134fi0.001696h2s0.00154argon0.00178co 20.00198ozone0.00214no 20.00198chlorine0.00321cyanogen0.00234krypton0.00374so 20.00293xe

30、0.00589bromid0.00364niton0.00973iodid0.00579gas0.00060ammonia0.0007liquid （room temp.g/cm 3 ）gasolene0.70olive oil0.92nitric acid1.50aether0.71fish liver oil0.95virtriol1.80petroleum0.76castor oil0.97bromine3.12alcohol0.79pure water1.00azoth14.20methyl0.80seawater1.03coal oil0.80vinegar1.05oil of0.8

31、6muriatic acid1.20turpentinebenzene0.88without water1.26glycerinpetrolatum0.9-0.93carbon bisulfide1.29plant oil0.9-0.93honey1.40solid （ room temp. g/cm3）cast steel7.80lead11.34organic1.18glasscarbon steel7.80-7.85magnesium1.738limestone2.60-3.0cast iron6.80-7.20zinc7.133asphaltum0.90-1.50aluminium2.

32、70chrome7.19phosphor1.82silver10.49manganese7.43carbon1.90-2.3013gold19.302natrium0.97copper8.93tungsten19.254health copper8.90tantalum16.60nickel8.90tin5.765nickel chrome8.40platinum21.45boiling point, vaporization heat, melting point, solution heat for kinds of materialmaterialmeltingsolution heat

33、boiling point（）vaporization （cal/g ）point( )（cal/g ）aether-11723.543584alcohol-11423.5478204carbon-11245.346.2584bisulfideice080100539heat conductivity and max using temp. for kinds of heat-insulating materialmaterialmax using temp.heating quotiety under room temp.（）（w/mk ）glass fiber3000.036rock co

34、tton3500.044slag cotton3500.040expanding perlite rock5500.047polyammonia foam plastic800.024polybenzene foam plastic600.031silicic acid calcium5500.054compound silicate fhp-vb7000.024compound silicate fhp-v7000.024dopesilicic acid aluminium4000.046（ drying ）silicic acid aluminium8000.046（wetting ）re

35、cord: as the correct data pls see the supplies instruction.the heat insulating material thickness for different tube dia under various temp.material ：rock cottonsurface wrappage ：aluminium or carbon steelhumidity ： 81%14ambient temp. ：15.4 wind speed ：3.8m/stube diatube temp （）in/dg mm /mm25 5075100

36、 125 150 175 200 225 250 275 300 325 350 375 400 425 4501/2 /15/21.3425 3030304050505060606080 80 80 80 80 80 803/4 /20/26.6725 3030404050506060607080 80 80 80 80 80 801/25/33.4025 3040404050606060707080 80 80 80 80 80 801/2 /40/48.2625 3040405050606070707090 90 90 90 90 90 902/50/60.3330 4040505060

37、607070707090 90 100 100 100 120 1203/80/88.9030 4040505060707070808090 110 110 120 130 130 1504/100/1140330 40505050607080809090 100 100 110 120 130 130 1606/150/168.330 40506070708080100 100 100 110 130 130 130 130 160 1608/200/219.140 50506070808090100 100 100 110 130 130 130 150 170 18010/250/273

38、.140 506060708080100 100 100 120 120 140 140 170 170 180 19012/300/323.940 506060708080100 100 100 120 140 140 170 170 180 190 20014/350/355.640 606060708080100 100 100 140 140 170 170 180 190 200 20016/400/406.440 606080808090100 100 100 140 150 170 180 180 190 200 21018/450/457.240 606080809090100

39、 100 110 150 160 170 180 180 190 22 21020/500/508.060 6060809090100 100 100 120 160 160 180 190 200 210 220 22024/600/609.6060 6060809090100 100 100 120 170 170 190 200 200 210 220 22026/650/660.4060 6060100 10090100 130 130 140 200 200 200 200 200 210 220 22028/700/711.2060 6070100 10090110 130 130

40、 140 200 200 200 200 200 210 220 22030/750/762.060 6070100 100 100 110 130 130 170 200 200 200 200 200 210 220 28036/900/91404070 7090100 100 100 110 160 170 180 200 200 200 200 200 210 220 28040/1000/1016.070 7090100 100 100 110 170 180 190 200 200 200 200 200 280 280 29042 /1050/1066.8070 7090100 100 100 110 170 180 190 200 200 200 200 280 280 290 30048 /1200/1219.2070 7090100 100 100 110 170 190 190 200 200 200 200 290 300 300 30054 /1350/1371.6070 70 100 100 100 100 150 180 190 190 200 200 200 280 300 300 300 30060 /1500/1524.0070 70100 100 100 100 160 180 200 200 200 200 280 280 300