顶部导向型单座调节阀是一种体积小、结构简单但却能适应苛刻工况条件的单座调节阀。该系列调节阀很容易制成波纹管密封型、蒸汽夹套型、加长型上阀盖等特殊结构。Simple structure and compact size characterize our topguided control valves. They are......