三菱土压平衡盾构机发泡系统具有一定的缺陷。参照海瑞克的发泡剂系统设计，改进了三菱土压平衡盾构机发泡系统。通过所需能力的计算，介绍系统部件选型。介绍了改造前后的系统原理及优缺点，改造后系统故障的排除方法。三菱土压平衡盾构机发泡系统的改造克服了原有系统的缺陷，节约了成本。

The foam system of an EPB shield machine manufactured by Mitsubishi Heavy Industries has some disadvantages, therefore reforms are made by referring to the design of the foam systems of shield machines manufactured by Herrenknecht A.G. In this way, the disadvantages of the original foam system are eliminated with the lowest cost. In the paper, the selection of the components of thefoam system based on calculation of the required capacities is presented. The principles and advantages/disadvantages of the original foam system and the reformed foam system, as well as the countermeasures for the malfunctions that may occur to thereformed foam system, are also presented.