电加热设计资料

9电热设计资料计量单位功率：W、kW 1kW=3.412BTU/hr(英热单位/小时)=1.36(马力)=864Kcal/hr重量：kg流速：m/minm3/min、kg/h5.比热：Kcal/(kg℃)

1kg=2.204621b(磅)1kcal/(kg℃)=1BTU/hr.oF=4186.8J/(Kg℃)功率密度：W/cm2压力：MPa导热系数：W/(m℃)

1W/c=6.4516W/in21W/(m℃)=0.01J/(cms℃)=0.578Btu/(ft.h.F)9.温度：℃ 1oF=9/5℃＋321R=9/5℃＋491.671K=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 统中的热损失全部的计算应以最恶劣的状况考虑：

最短的运行周期加热介质的最大重量〔流淌介质则为最大流量〕设计电加热器系统的步骤〔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准时间。打算发热元件的护套材料及功率密度。系统起动时所需要的功率：系统运行时所需要的功率：管道平面式中符号，含义如下：P功率：kWm1介质重量：kg介质比热：kcal/kg℃m2容器重量：kgc2介质比热：kcal/kg℃m3每小时增加的介质重量或流量:kg/hc3介质比热：kcal/kg℃h加热时间：h

QW/m；W/m2λ 保温材料的导热数：W/mkδ 保温材料厚度：mmd管道外径：mmL管道长度：mS系统的散热面积：m2△T介质和环境温度之差或温升：℃有关加热功率计算的参考数据〔如需更多数据，请来电、来函询问〕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0.42ABS0.35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自然气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物质比重物质比重物质比重物质比重氢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0.00154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〔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/cm3〕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岩棉

300350

常温下的导热系数〔W/mk〕0.0360.044矿渣棉3500.040膨涨珍宝岩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硅酸铝〔湿法制造〕8000.046注：准确的数据请查供给商的说明书不同温度下，不同管径的保温材料的厚度管道直径/公称直径/毫米管道温度〔℃〕255075100125150175202325250275300325350375400425450材料管道直径/公称直径/毫米管道温度〔℃〕2550751001251501752023252502753003253503754004254501/2″/15/21.342530303040505050606060808080808080803/4″/20/26.672530304040505060606070808080808080801″/25/33.402530404040506060607070808080808080801/2″/40/48.262530404050506060707070909090909090902″/50/60.33304040505060607070707090901001001001202303″/80/88.903040405050607070708080901101101202301301504″/100/1140330405050506070808090901001001101202301301606″/150/168.330405060707080801001001001101301301301301601608″/200/219.1405050607080809010010010011013013013015017018010″/250/273.14050606070808010010010012023014014017017018019012″/300/323.94050606070808010010010012023014017017018019020014″/350/355.64060606070808010010010014014017017018019020230016″/400/406.44060608080809010010010014015017018018019020231018″/450/457.2406060808090901001001101501601701801801902221020″/500/508.060606080909010010010012023016018019020231022023024″/600/609.6060606080909010010010012023017019020230021022023026″/650/660.406060601001009010013013014020230020230020231022023028″/700/711.206060701001009011013013014020230020230020231022023030″/750/762.060607010010010011013013017020230020230020231022028036″/900/91404070709010010010011016017018020230020230020231022028040″/1000/1016.070709010010010011017018019020230020230020238028029042″/1050/1066.8070709010010010011017018019020230020230028028029030048″/1200/1219.2070709010010010011017019019020230020230029030030030054″/1350/1371.607054″/1350/1371.60707010010010010015018019019020230020238030030030030060″/1500/1524.00707010010010010016018020230020230028028030030030030066″/1650/1676.80707010010010010017019020230020230028030030030030030072″/1800/1828.807080100100100100170190202300202300280300300300300300罐