Spjällventiler

Spjällventiler, often referred to as butterfly valves in English, are a type of quarter-turn valve used to control or isolate flow. They consist of a disc mounted on a rod or shaft within the valve body. When the valve is open, the disc is rotated 90 degrees so that it is parallel to the flow. When the valve is closed, the disc is rotated 90 degrees to be perpendicular to the flow, blocking the passage.

The primary advantage of spjällventiler is their simplicity, compact design, and relatively low cost. They are suitable for a wide range of applications, including water treatment, HVAC systems, and industrial processes. The disc presents some resistance to flow even when fully open, which can lead to a slight pressure drop. They are generally not recommended for applications requiring very precise flow control or for handling highly viscous fluids.

Spjällventiler can be operated manually using a lever or gearbox, or they can be automated with electric, pneumatic, or hydraulic actuators. The seating material for the disc can vary, including soft materials like rubber or PTFE for bubble-tight shutoff, or metal for high-temperature and high-pressure applications. Their ease of operation and maintenance makes them a popular choice in many industries.