外压浮球是浮球式疏水阀中的关键零件,它的质量对疏水阀的性能起着决定性的作用。浮球式疏水阀的损坏大多因浮球材料选择太薄,强度不够,在高温和外压的作用下,往往由于壁厚不够,浮球失稳而被压瘪,致使疏水阀动作失灵。但若浮球壳壁太厚,又会减少浮球应有的浮力,影响疏水阀的开启能力。本文就浮球式疏水阀的外压浮球的设计计算方法问题,根据目前国际上通用的计算外压容器的方 External pressure float ball float trap is a key component, its quality of the performance of the trap plays a decisive role. Float trap damage mostly due to the selection of the float material is too thin, the strength is not enough, under the action of high temperature and pressure, often due to insufficient wall thickness, float ball instability and was deflated, resulting in trap failure. However, if the floating shell wall is too thick, it will reduce the buoyancy of the float and affect the opening ability of the trap. In this paper, floating ball trap external pressure float design and calculation methods, according to the current international common calculation of external pressure vessel