Parameters / Specifications Model: FISHER 657‑30 Actuator Type: Direct‑acting, spring‑oppose diaphragm actuator for sliding‑stem valve Actuation Mode: Spring return (fail‐safe) Signal Pressure Range: Typically 3–15 psig (0.2–1.0 bar) or 6–30 psig (0.4–2.0 bar) Effective Diaphragm Area (Size 30): Approx. 46 in² (≈297 cm²) Maximum Stem Travel (Size 30): Approx. 0.75 in (≈19 mm) Maximum Output Thrust (Size 30): Approx. 2,300 lb (≈10,230 N) Operating Temperature Range (Standard Construction with Nitrile Elastomers): Approx. –40 °F to +180 °F (≈ –40 °C to +82 °C) Construction Materials: Durable cast iron/steel body and spring case, molded diaphragm, corrosion‑resistant design Mounting: Integrated pad for digital positioner or valve controller attachment Approximate Weight (Actuator only, Size 30): ~36 lb (≈16 kg) Combined Valve Body/Actuator Usage: Size 30 suggests smaller valve body (e.g., 1.5″ flow size in some configurations)
