Manual Ventilation Butterfly Valve is a cost-effective,easy-to-operate flow control device,mainly used for regulating air volume,isolating and cutting off air,flue gas,and dust-laden gas in ventilation,dust removal,HVAC,and industrial ventilation systems.It is widely applied in factory workshops,warehouses,civil buildings,and small-to-medium-sized industrial projects where automatic control is not required,relying on manual operation to achieve pipeline on-off and air volume adjustment.

The valve features a simple and compact structure,consisting of a valve body,butterfly plate,valve stem,and manual operating mechanism(handwheel or handle).The valve body adopts a wafer-type or flange-type connection,which is light in weight,small in installation space,and easy to assemble and disassemble,greatly reducing installation costs and pipeline layout space.The manual operating mechanism is designed with a labor-saving structure,allowing operators to easily rotate the butterfly plate 0–90 degrees with a small force,realizing stepless adjustment of air volume or full on-off control.

In terms of material selection,the valve body and butterfly plate are made of high-quality carbon steel as standard,which is sturdy and durable,suitable for general ventilation scenarios.For humid,slightly corrosive,or clean occasions(such as food processing auxiliary ventilation),304/316L stainless steel materials can be customized to enhance corrosion resistance and hygiene performance.The sealing structure adopts high-quality soft seal(EPDM or PTFE),which has excellent airtightness,effectively preventing air leakage and flue gas backflow,ensuring the stability of the ventilation system.

Compared with electric and pneumatic types,the manual ventilation butterfly valve has the advantages of low cost,simple maintenance,and high reliability.It has no complex electrical or pneumatic components,avoiding faults caused by power outages or air source failures,and is suitable for occasions with simple control requirements.The valve is equipped with a position limit device,which can accurately fix the opening angle of the butterfly plate,facilitating operators to adjust and maintain a stable air volume.

It is widely used in factory ventilation and exhaust,workshop dust removal pipelines,civil building HVAC systems,small boiler flue gas discharge,and other scenarios.With its simple operation,reliable performance,and cost-effectiveness,it has become a common and practical flow control accessory in ventilation systems.The valve has a long service life,few wearing parts,and only requires regular inspection and lubrication,which can effectively reduce later maintenance costs.