Manual multi-blade sector butterfly valve

The manual multi-blade sector butterfly valve is a practical mechanical flow control device integrating multi-blade linkage and sector plate structure, specially designed for large-caliber ventilation ducts, fan pipelines and industrial flue gas systems. Different from single-disc butterfly valves, it adopts combined sector blades and manual operating mechanism, which features larger flow area, more stable airflow regulation and lower operating resistance. It is mainly used to adjust air volume, balance pipeline pressure and cut off airflow in industrial ventilation, hot air delivery and dust removal systems, and is a cost-effective choice for projects without automatic control requirements.

The valve is constructed with a sturdy integral frame, multiple synchronized sector blades, connecting linkage, solid valve shafts and manual operating parts. The frame and blades are generally made of high-quality carbon steel or galvanized steel, undergoing rigorous welding and anti-rust treatment to enhance structural rigidity and durability. All sector blades are connected by a precise linkage system, so they rotate simultaneously at the same angle when operated manually. The manual hand lever or handwheel directly drives the transmission parts to adjust the opening degree within 90 degrees. When fully open, the sector blades unfold completely to form a smooth flow channel with minimum pressure drop. When partially closed, the overlapping blades achieve stepless air volume regulation. When fully closed, the blades fit tightly against each other and the frame to form a reliable seal and block airflow thoroughly.

This product has many outstanding practical advantages. First of all, the multi-blade sector design greatly reduces operating torque, so operators can easily complete opening, closing and adjustment even on large-size valves. Compared with single large disc valves, it runs more flexibly and is not prone to jamming under wind pressure. Secondly, the segmented blade structure makes airflow distribution more uniform, effectively avoiding turbulent flow and pipeline vibration during regulation. The all-steel reinforced structure resists deformation caused by long-term positive and negative air pressure and fan vibration, ensuring stable long-term operation. In addition, the manual drive requires no power supply or supporting control circuits, which is applicable to various on-site environments and cuts down operation and matching costs.

The overall structure is simple with fewer vulnerable components, bringing low failure rate and convenient daily maintenance. The smooth surface of sector blades is not easy to gather dust, further reducing cleaning workload. It adapts to normal temperature ventilation, medium-temperature flue gas and slightly dusty working conditions, and covers a full range of specifications to match different duct diameters.

It is widely applied in industrial factory ventilation, boiler fan inlet and outlet pipelines, cement and metallurgical workshop duct systems, dust removal equipment and conventional flue gas exhaust projects. With easy operation, stable performance and high cost performance, the manual multi-blade sector butterfly valve has become a common and trusted flow control component for large industrial ductwork.