What is a flanged butterfly valve?

A flanged butterfly valve is a type of butterfly valve that comes with a flange. It achieves sealing by connecting to the flange of a pipeline through bolts. It controls the flow of the medium in the pipeline by rotating the butterfly plate within a range of 0 to 90 degrees, allowing for the cutting off, opening, or regulating of the flow. Its core advantages lie in "stable flange connection + efficient flow control by butterfly valve": the flange connection provides strong sealing and does not require the disassembly of the entire pipeline for installation and removal, making it suitable for scenarios with vibration or pressure fluctuations; the butterfly valve body is small in size, has low flow resistance (flow resistance coefficient ≤ 0.2), and opens and closes quickly, widely used in low and medium pressure pipeline control scenarios in water treatment, municipal, chemical, and HVAC industries.

 

Key points for selecting a flanged butterfly valve

First, clarify the medium and working conditions: for non-corrosive media, choose a cast iron or carbon steel valve body; for weakly corrosive media, choose a 304 or 316L stainless steel valve body; for clean media (such as tap water, steam), choose a soft seal; for media containing minor particles (such as sewage, dusty gas), choose a metal seal; for scenarios with vibration or pressure fluctuations, prioritize flanged connection (more stable). Next, match the flange parameters: the flange standard and seal face type must be exactly the same as the pipeline flange; the nominal diameter should be calculated based on the pipeline flow. Then, confirm the operation method: for unattended pipelines, choose electric or pneumatic; for low-frequency operations, choose manual; for explosion-proof scenarios, choose pneumatic or explosion-proof electric. Finally, check the details: the flange gasket material should be compatible with the medium (such as nitrile rubber gasket for oily media, metal wound gasket for high-temperature media); for long-term disuse, regularly open and close the valve to prevent the sealing surface from sticking.

 

Applications of flanged butterfly valves

In the water treatment industry, they are used in the main inlet and outlet pipes of sewage treatment plants and the outlet control pipes of sedimentation tanks. The carbon steel or stainless steel valve body is resistant to sewage corrosion, and the flange connection is suitable for pressure fluctuations in the main pipes, ensuring the stable operation of the water treatment system. In the municipal industry, they are used in the main lines of urban tap water networks and the outlet pipes of rainwater pumping stations. The flange connection ensures long-term reliable sealing of the network and meets the requirements of smart water management and dispatching. In the chemical industry, they are used in the pipelines for transporting weakly corrosive solvents (such as methanol, ethanol). The 316L stainless steel valve body and metal seal are resistant to medium corrosion, suitable for continuous operation in chemical production. In the HVAC industry, they are used in the main pipes of the chilled water system of central air conditioning and the main pipes of heating systems. The soft-sealed flanged butterfly valve has good sealing performance and can quickly open and close to regulate the system temperature. Additionally, in the power (cooling tower circulating water main pipes) and food (normal temperature raw material conveying pipes) industries, they are also used in low and medium pressure pipeline control, balancing reliability and practicality.