... DN:20-500mm Best price and quality. Pneumatic Diaphragm Steam Control Valve(150Lb, 300Lb, 600lb,900Lb,etc) Features:Top-guided ... Single Seated Control Valves, compact valve body, less component, esay to maintain.The ... , inherent adjustable ratio is 50:1. The valve actuator use multiple springs structure, and the height reduce 30%, the weight reduce ...