wafer vs lug butterfly valve

The Core Design: Simple, Compact, and Effective A wafer butterfly valve is a type of quarter-turn rotary valve used to start, stop, or regulate the flow within a pipeline. Its name gives away its two main features: "Butterfly": It gets its name from the disc, which is the core component. This disc sits in the center of the pipe and rotates on a shaft. When turned a quarter-turn (90 degrees), it moves from a position blocking the flow (closed) to being parallel with the flow (fully open), much like a butterfly opening and closing its wings. "Wafer": This refers to its body style. Unlike lug-style valves, a wafer valve does not have protruding threads (lugs) on its body. Instead, it is a slim, disc-like body that is "sandwiched" or clamped between two pipeline flanges using long bolts that pass through the entire assembly. Here’s a quick look at its main components:     Component Function Body The slim, central housing that contains the disc and fits between flanges. Disc The rotating "butterfly" element that controls flow. Can be centered or offset for better performance. Stem The shaft that connects the disc to the actuator and transmits the turning force. Seat The inner lining (often made of elastomers like EPDM or Viton) that creates a tight seal against the disc when closed. Actuator The device used to turn the stem (e.g., manual lever, gearbox, or automated electric/pneumatic unit). Key Advantages: Why Choose a Wafer Design? The wafer-style construction is chosen for specific, powerful reasons that make it a go-to solution for many applications: Lightweight and Compact: With its slim profile, it adds minimal length and weight to a piping system. This saves space and makes installation easier, especially in tight spots. Cost-Effective: It requires less material to manufacture than lug or full-body valves and uses fewer bolts to install, leading to lower overall cost. Easy Installation and Maintenance: Being sandwiched between flanges simplifies installation. Maintenance often involves simply removing the flange bolts to access the internals. Low Pressure Drop: When fully open, the disc presents minimal obstruction to the flow, ensuring efficient system operation. Quick Operation: The quarter-turn operation allows for very fast opening and closing. Where Are Wafer Butterfly Valves Used? Their versatility makes them suitable for a wide range of industries and media: