储罐设计

I目录1设计...............................................................................................................................I1.1工艺参数的设定..............................................................................................................I1.1.1设计压力·······················································································I1.1.2筒体的选材及结构···········································································I1.1.3封头的结构及选材···········································································I1.2设计计算........................................................................................................................II1.2.1筒体壁厚计算················································································II1.2.2封头壁厚计算·············································································III1.3压力实验........................................................................................................................IV1.3.1水压试验·····················································································IV1.3.2水压试验的应力校核：···································································IV1.4附件选择.......................................................................................................................IV1.4.1人孔选择及人孔补强····································································IV2.4.3进出料接管的选择·······································································VI1.4.4液面计的设计··········································································VIII1.4.5安全阀的选择··········································································VIII1.4.6排污管的选择··········································································VIII1.4.7鞍座的选择·············································································VIII1.4.8鞍座选取标准·············································································IX1.4.9鞍座强度校核··············································································X1.4.10容器部分的焊接··········································································XI1.5筒体和封头的校核计算.............................................................................................XI1.5.1筒体轴向应力校核·······································································XI1.5.2筒体和封头切向应力校核···························································XIII2液氨储罐的泄漏及处理方法.............................................................错误!未定义书签。2.1液氨泄漏的危害..............................................................................错误!未定义书签。2.2泄漏的危害......................................................................................错误!未定义书签。2.2.1生产运行过程中危险性分析······································错误!未定义书签。2.2.2设备、设施危险性分析············································错误!未定义书签。2.3液氨储罐泄漏事故的应急处置措施..............................................错误!未定义书签。I2设计2.1工艺参数的设定2.1.1设计压力液化气体储罐装安全阀，设计压力可取最大操作压力的1.05-1.10倍。通过公式P1.1P1.12.032.3MPa设，因此我们的设计压力P2.3MPa。表2-1设计参数设计要求参数设计压力2.3Mpa设计温度50℃储存物料液氨储罐体积50m32.1.2筒体的选材及结构根据液氨的物性选择罐体材料，碳钢对液氨有良好的耐蚀性腐蚀在0.1/mm年以下，且又属于中压储罐，可以考虑20R和16MnR这两种钢材。如果纯粹从技术角度看，建议选用20R类的低碳钢板，16MnR钢板的价格虽比20R贵，但在制造费用方面，同等重量设备的计价，16MnR钢板为比较经济。所以在此选择16MnR钢板作为制造筒体和封头材料。钢板标准号为GB6654-1996。常温储罐有两种形式：球形贮罐和圆筒形贮罐。球形储罐具有投资少,金属耗量少,占地面积少等优点,但是加工制造及安装复杂,焊接工作量大,因此安装费用较高。一般用于储存总量大于5003m或单罐容积大于2003m时；圆筒形贮罐具有加工制造安装简单,承压能力较好，安装费用少等优点,但是金属耗量大占地面积大,所以在总贮量小于5003m,单罐容积小于1003m时选用卧式贮罐比较经济。由于圆筒形贮罐按安装方式可分为卧式和立式两种。根据工艺要求，液氨储量为503m，因此，液氨储罐可设计为卧式圆筒形[1]。2.1.3封头的结构及选材封头有多种形式，半球形封头就单位容积的表面积来说为最小，需要的厚度是同样直径圆筒的二分之一，从受力来看，球形封头是最理想的结构形式，但缺点是深度大，直径小时，整体冲压困难，大直径采用分瓣冲压其拼焊工作量也较II大。椭圆形封头的应力情况不如半球形封头均匀，但对于标准椭圆形封头与厚度相等的筒体连接时，可以达到与筒体等强度。它吸取了蝶形封头深度浅的优点，用冲压法易于成形，制造比球形封头容易，所以选择椭圆形封头，结构由半个椭球面和一圆柱直边段组成。查椭圆形封头标准（JB/T4737-95）以内直径为公称直径的封头封头取与筒体相同材料[4]。表2-2椭圆封头标准内径曲面高度h1直边高度h2内面积Fi/m2容积V/m32600650407.632.51图2-1封头2.2设计计算2.2.1筒体壁厚计算确定容器的公称直径、筒体长度已知：设计的液化石油气储罐的理论体积为3=50mV理论2i V/4DL2V封实际装量系数 0.9V/V理论实际设：容器的公称直径为iD筒体的长度为L当2i50=4DL则推出92i5010=0.785LD估根据GB/9019-2001查表可知：容器的公称直径DN=2600长度L=8500mm查《压力容器材料使用手册-碳钢及合金钢》得16MnR的密度为7.85t/m3，熔点为1430℃，许用应力列于下表：表2-316MnR许用应力III钢号板厚/㎜在下列温度（℃）下的许用应力/Mpa16MnR201001502002503006～167017017017015614416～366316316315914713436～605715715715013812560～10053153150141128116圆筒的计算压力为2.3Mpa,容器筒体的纵向焊接接头和封头的拼接接头都采用双面焊或相当于双面焊的全焊透的焊接接头，取焊接接头系数为1.0,全部无损探伤。取许用应力为170Mpa，则：筒体计算厚度为：2.32600t17.656217012.32citcpDmmp钢板厚度负偏差10.8Cmm,查材料腐蚀手册得50℃下液氨对钢板的腐蚀速率小于0.1mm/y，所以双面腐蚀取腐蚀裕量。22Cmm所以设计厚度为：2t19.656dtCmm圆整后取名义厚度为：t24ndtCmm圆整值图2-2筒体的相关尺寸2.2.2封头壁厚计算根据标准椭圆形封头得a:b=2:1封头计算公式2.32600t=17.648217010.52.320.5citcpDmmp故封头厚度近似等于筒体厚度，取同样厚度，则名义厚度tn1=24mm。因为封头壁厚≥20mm则标准椭圆形封头的直边高度h0=40mm。IV2.3压力试验2.3.1水压试验试验方法：试验时容器顶部应设排气口，充液时应将容器内的空气排尽，试验过程中，应保持容器外表面的干燥。试验时压力应缓慢上升，达到规定试验压力后，保压时间一般不少于30min。然后将压力降至规定试验压力的80%，并保持足够长的时间以便对所有焊接接头和连接部位进行检查。如有渗漏，修补后重新试验。水压试验时的压力Tp1.251.252.32.875tpMpa2.3.2水压试验的应力校核：水压试验时的应力2.8752600241163.93822241TieTepDtMpat查《化工容器设计》得16MnR钢板的常温强度指标MPas325，水压试验时的许用应力为0.90.91.00325292.5sMpa故σT＜0.9ФσS筒体满足水压试验时的强度要求。2.4附件选择2.4.1人孔选择及人孔补强人孔的作用：为了检