Manual Ventilation Butterfly Valve

Manual Ventilation Butterfly Valve is a quarter-turn rotary flow control valve dedicated to gas regulation and shut-off in low-pressure ventilation,dust collection and flue gas systems.Operated manually via handle,worm gear or handwheel,it features a lightweight,compact structure and 90°quick opening/closing.

Product Structure

Valve Body:Manufactured from carbon steel,stainless steel or cast iron,available in circular or rectangular designs to match duct specifications.

Butterfly Disc:Centrally mounted plate rotating 0–90°to adjust flow area;welded construction for high strength and minimal internal obstructions.

Stem&Actuator:Connected to the disc,driven by manual handle,worm gear or gearbox for precise positioning;large-diameter models often use worm gears for torque reduction.

Sealing System:Metal-to-metal,graphite or high-temperature elastomer seals providing reliable shut-off;metal seals excel in high-temperature applications.

Bearings&Bushings:Low-friction bearings ensure smooth operation and extended service life.

Working Principle

By rotating the manual actuator,the stem turns the butterfly disc within the body.At 0°(fully open),the disc aligns parallel to flow,minimizing pressure loss.At 90°(fully closed),the disc seals against the seat to block gas passage.Intermediate angles enable precise airflow modulation.

Key Features

Manual Operation:Flexible,reliable and independent of external power;worm gear models offer fine adjustment.

Lightweight&Compact:Low weight,small footprint,easy installation and maintenance.

Low Torque:Smooth,effortless operation even in large sizes.

Wide Temperature Range:Standard:-29°C to 300°C;high-temperature variants up to 425°C.

Low Pressure:Rated for 0.05–0.6 MPa,ideal for large-diameter ventilation ducts.

Leak-proof Performance:Hard or soft sealing options ensure low leakage.

Corrosion Resistance:Carbon steel,stainless steel or alloy constructions adapt to dusty,corrosive gases.

Applications

Environmental Protection:Dust collection systems,baghouses,industrial dust control.

Metallurgy&Building Materials:Furnace flue gas,kiln ventilation,cement plant exhaust.

Power Plants:Boiler ducts,generator cooling,boiler air flow control.

Chemical&Petrochemical:Corrosive gas pipelines,ventilation systems.

HVAC&Construction:Commercial ventilation,underground garage air control.

Glass&Ceramics:High-temperature furnace exhaust and combustion air.