- 1 - 6th edition No. SS2-8110-0530 Weir Diaphragm Control Valves Model VDD INTRODUCTION Model VDD weir diaphragm control valves are designed for slurry or corrosive material handling service. The valve body adopts a flow passage structure free from interrupted liquid trapping, which minimizes clogging by fluids containing solid substances. Abrasion- and corrosion- resistant linings can be applied to the valve interior. The actuator intergrated with simplest mechanisms utilizes a compact yet powerful diaphragm actuator loaded with multiple springs. The model VDD valves are widely applicable for reliable control of low-pressure process lines for slurry and corrosive fluids. SPECIFICATIONS Body Type Weir diaphragm valve Nominal size 1/2, 3/4, 1, 1., 2, 2., 3, 4 inches Pressure rating For operating temperature and pressure range, refer to Table 1, 3, 5, 6, 7 and 8. End connection JIS10K, ANSI150 (BS10-1962, UK standard, for flange thickness) End connection Flanged end FF: Hard natural rubber, chloroprene lining, and SCS13 RF (equivalent): PTFE, ETFE glass lining (RF section dimensions are determined by manufacturers.) Material For body / diaphragm combinations, refer to Table 1. Bonnet Plain bonnet (Non liquid-contacting, non pressurized vessel) Bonnet material: FCD-S Trim type Diaphragm type Flow characteristics Inherent flow characteristics (approximately linear) Stem material SUS403 Actuator Type Single acting diaphragm actuator Action Direct or reverse action Diaphragm Cloth-embedded ethylene propylene rubber Spring range Refer to Table 5 through Table 8. Supply pressure 200, 270 kPa {2.0, 2.8 kgf/cm2} Note) Spring range and air supply pressure vary depending on nominal size. Air connection Rc1/4 or 1/4NPT internal thread 5 1 Specifications are subject to change without notice. “This product is designed for general industrial use.”