浮头式换热器（Ⅱ型）设计.docVIP

本科毕业设计（论文） 浮头式换热器（Ⅱ型）设计 学院（系）：车辆与能源学院 专 业：热能与动力工程 学生 姓名： 任晓 学 号： 指导 教师： 于敏之 答辩 日期： 2012.6.25 摘 要 换热设备是炼油厂的典型设备，主要用于原有和油品等的换热或冷却。换热器种类很多，根据冷、热流体热量交换的原理和方式基本上可分三大类即：间壁式、混合式和蓄热式。在三类换热器中，间壁式换热器应用最多，管壳式换热器是间壁式换热器的主要类型。本次我的设计题目是减二中/原油冷却器，换热器形式选用管壳式换热器中的浮头式。 首先是根据给定的工艺参数进行前期的工艺计算，这部分的主要目的是确定浮头式换热器的具体型号，以及一些对接下来的结构设计有影响的关键数据。工艺计算的大体内容为传热面积计算、初步选型、传热系数校核、有效平均温度差、校核传热面积、流体助力计算、壁温计算。其中初步选型后要对初选的传热系数进行校核，如果不合格要要重新选型、反复试算。在流体阻力校核部分要考虑操作成本与制造成本的平衡关系。 其次是结构计算。这部分是对管板、接管、法兰等具体零件的设计和选用。材料选用方面：对于主要承压元件选用Q345R为材料。由于介质腐蚀性不高，所以选用20钢为换热管的材料。材料的选用与制造成本紧密相连，所以应该在保证设计要求的前提下尽量降低成本。 关键词 浮头式换热器；换热管；选材 Abstract Heat exchanger is a typical refinery equipment, mainly for the original and the heat transfer oil, etc., or cooling. Many types of heat exchangers, according to the cold, the thermal fluid heat exchange principles and methods are basically divided into three main categories namely: partitions type, hybrid and regenerative. In the three types of heat exchangers, the partitions heat exchangers most widely used. Shell and tube heat exchanger is the partitions of the main types of heat exchangers. The subject of my design is to reduce II / oil coolers, heat exchangers in the form of shell and tube heat exchangers used in the floating head.  First, according to the given process parameters pre-process calculation, the main purpose of this section is to determine the specific floating head heat exchanger models, and some impact on the structural design of the next key data. Process in general terms the contents of the heat transfer area calculation, the initial selection, checking the heat transfer coefficient, effective mean temperature difference, check the heat transfer area, fluid power calculations, the wall temperature calculation. Which after the initial selection of the heat transfer coefficients of primary check, if failed to b