一、前言选择最合适的管道尺寸对化工厂具有很大的经济意义,因为化工管道的成本约为工厂总投资的10～20%。管道尺寸的确定需分二步进行,首先按速度推荐值确定公称管道尺寸;然后根据介质特性和确定的管径计算压力降。对于主要管线进出口之间的最大压力降总值是由全厂工程设计给定的,这规定的压力降基本上确定了物料管线的管径,如果压力降不合适,就有必要修改管径。本文着 I. Preface Choosing the most suitable pipe size is of great economic importance to chemical plants because the cost of chemical pipelines is about 10-20% of the total plant investment. Pipe size to be determined in two steps, first of all, according to the speed recommended to determine the nominal pipe size; and then calculate the pressure drop based on media characteristics and determine the diameter. The total value of the maximum pressure drop between the main pipeline import and export is given by the whole plant engineering design, which stipulates that the pressure drop basically determines the pipe diameter of the material pipe. If the pressure drop is not suitable, it is necessary to modify the pipe diameter . This article