3000002C压载舱牺牲阳极计算书

CALCULATIONOFSACRIFICIALANODESINBALLASTTANKS3000002CP2/41.GENERALDESCRIPTION说明1.1Thealuminumalloysacrificialanodeswithboltingtypeshallbefittedinwaterballasttanksincludingpeaktanks.ThedesignofcathodicprotectionbymeansofsacrificialanoderefertothestandardGB8841-88.本船压载水舱包括艏艉尖舱内将安装螺栓连接型式的铝合金牺牲阳极，用牺牲阳极作阴极保护的设计参照GB8841-88标准。1.2Thecalculationofaluminumanodesforwaterballasttankstobeaccordingtothecontractspecificationasfollowingdesigncondition.Lifetime:five(5)yearsBallastratio:50%Meancurrentdensity:5.4mA/m2压载水舱铝合金阳极根据“建造说明书”按如下设计条件计算：使用寿命5年压载率50%保护电流密度5.4mA/m21.3Theproductsofaluminumanodeswith5yearslifetimeshouldbeaccordingtomanufacturer’srecommendationandtheBuilder’spractice.使用寿命为5年的铝阳极可以采用制造厂商推荐的或建造厂成熟的产品。2.CHEMICALCOMPONENTOFAL-ANODES(%)铝合金牺牲阳极的化学成分TYPE种类COMPOSITION化学成分ZnInCdImpurityMax杂质，不大于AlSiFeCuA11GB/T4948-2002铝-锌-铟-镉2.5~4.50.018~0.0500.005~0.0200.100.150.01Excess余量3.THEAL-ANODESPARAMETER选用铝合金牺牲阳极的参数STANDARD标准号TYPE型号CURRENT（If）发生电流值（If）CURRENTCAP.实际电容量SIZE尺寸NETWT.净重(kg/Pec.)GROSSWT.毛量(kg/块)GB/T4948-2002A11T-635mA2400Ah/kg495×140×~559.0~104.QUANTITYOFANODESCALCULATION牺牲阳极用量计算ITEM保护部位TYPE型号N.WEIGHTCURRENTPRO.AREAPRO.CUR.TOTALCUR.T.QUA.P.QUA.净重量电流值保护面积保护电流总电流需要量实配Kg/pec.mAm2mA/m2mAPec.块Pec.块AFTPEAKTK.(W.B.)艉尖舱（压载水舱）A11T96354263.605.423023.4418.118NO.10DB.W.B.TK.NO.10底压载水舱A11T96351804.005.49741.607.78NO.9W.B.TK.(P&S)NO.9压载水舱（左/右）A11T96354610.405.424896.1619.620/20NO.8W.B.TK.(P&S)NO.8压载水舱（左/右）A11T96355108.755.427587.2521.722/22NO.7W.B.TK.(S)NO.7压载水舱（右）A11T96357298.125.439409.8631.032CALCULATIONOFSACRIFICIALANODESINBALLASTTANKS3000002CP3/4NO.7W.B.TK.(PL)NO.7压载水舱（左下）A11T96354661.005.425169.4019.820NO.7W.B.TK.(PU)NO.7压载水舱（左上）A11T96352725.565.414718.0211.612NO.6W.B.TK.(P&S)NO.6压载水舱（左/右）A11T96357386.595.439887.5831.432/32NO.5W.B.TK.(P&S)NO.5压载水舱（左/右）A11T96357386.595.439887.5831.432/32NO.4W.B.TK.(P&S)NO.4压载水舱（左/右）A11T96357386.595.439887.5831.432/32NO.3W.B.TK.(P&S)NO.3压载水舱（左/右）A11T96357644.555.441280.5532.533/33NO.2W.B.TK.(P&S)NO.2压载水舱（左/右）A11T96357316.735.439510.3231.132/32NO.1W.B.TK.(P&S)NO.1压载水舱A11T963512775.205.468986.1054.354FOREPEAKTK.(W.B.)艏尖舱（压载）A11T96357549.505.440767.3032.132ANODESQUANTITYCALCULATIONFORMULA：牺牲阳极用量计算公式fjjjISiN×cRemark：Nj—Quantityofanodesforprotectedstructurebycalculation（piece）ij—Protectcurrentdensity(mA/m2)Sj—Areaofprotectedstructure(m2)If—Occurcurrentofanode(mA)C—Ballastratio,C=0.5式中：Nj—被保护结构所需的阳极数量,（块）ij—保护电流密度,(mA/m2)Sj—被保护结构面积,(m2)If—牺牲阳极发生电流量,(mA)C—压载比率,C=0.5CALCULATIONOFSACRIFICIALANODESINBALLASTTANKS3000002CP4/45.LIFETIMEOFANODESCALCULATION牺牲阳极使用寿命计算t=8760Im1000mQ×k1t=(9×2400×1000)÷(0.6×635×8760)×0.85=5.50(Year年)Remark：m—Massofanode（kg）Q—Effectivecurrentcapacity(Ah/kg)Im—Averageoccurcurrentofanode,Im=0.6×If(mA)If—Occurcurrentofanode(mA)1/k—Usingquotietyofanode,1/k=0.85式中：m—牺牲阳极的质量,（kg）Q—牺牲阳极的实际电容量,(Ah/kg)Im—牺牲阳极平均发生电流量,Im=0.6×If(mA)If—牺牲阳极发生电流量,(mA)1/k—牺牲阳极的利用系数，1/k=0.85