--- title: "Sanitary Butterfly Valves: Working Principle, Types, and Applications" date: 2026-07-12T08:51:55Z modified: 2026-07-16T03:38:46Z permalink: "https://www.hyflowtech.com/blog/basic/sanitary-butterfly-valves-working-principle-types-applications/" type: post status: publish excerpt: "" wpid: 1879 categories: - basic featured_image: "https://www.hyflowtech.com/wp-content/uploads/2026/07/image-44-e1784095282363.webp" featured_image_alt: An infographic on sanitary butterfly valve timestamp: 2026-07-16T03:38:46Z tags: - basic --- Sanitary butterfly valves regulate the passage of liquid, gas, or slurry through hygienic process lines by using a rotating disc to allow or restrict fluid flow. This disc is mounted centrally in the pipe bore and rotates 90 degrees from the fully open to the fully closed position. Due to this straightforward design, it is considered one of the most commonly used flow regulation valves in the industry. ![A Sanitary Butterfly Valve Operate](https://www.hyflowtech.com/wp-content/uploads/2026/07/image-43-edited.webp) ## How Does a Sanitary Butterfly Valve Operate? All sanitary butterfly valves are designed using a disc that rotates around a central axis in a circular fashion. The valve is open, and there is minimal resistance when the disc is aligned with the direction of flow and is rotated 90 degrees to create maximum resistance to flow. This disc is attached to an actuator/valve handle outside the valve body. Inside the valve body, there is a valve seat that is lined with materials like silicone rubber or EPDM, which seals with the edge of the disc. Therefore, it is through the seat material that the sealing capacity of the disc can be established, as this is influenced by the temperatures and cleaning chemicals used. Ball valves have greater resistance to flow than butterfly valves at their full opening position; therefore, butterfly valves are used in big diameter pipes. ## Types of Sanitary Butterfly Valves by Connection Connection type is always the first parameter to consider when choosing. It depends on how the valve will be connected to the piping, its pressure resistance, and the necessity to be able to remove it often for cleaning purposes. ### Tri-Clamp Butterfly Valve [Tri-clamp butterfly valve](https://www.hyflowtech.com/product/tri-clamp-butterfly/) is the most widespread type used in sanitary processing. It is attached through tri-clamp ferrules on each side, making it possible to take the valve out for cleaning and put it back on without any other tool than a wing bolt. [ ![Tri Clamp butterfly valve](https://hyflowtech.b-cdn.net/wp-content/uploads/2026/04/%E5%8D%AB%E7%94%9F%E7%BA%A7%E4%B8%8D%E9%94%88%E9%92%A2%E8%9D%B6%E9%98%80stainless-steel-sanitary-butterfly-valve3-2.jpg) **Tri Clamp butterfly valve** The sanitary stainless steel butterfly valve is designed for demanding hygiene environments in food, pharmaceutical, and bioengineering industries. View Details ](https://www.hyflowtech.com/product/tri-clamp-butterfly/) ### [Butt Weld Butterfly Valve](https://www.hyflowtech.com/product/butt-weld-butterfly-valve/) Butt welding valves are welded permanently into the piping system with no joints and no crevices created at all. This works well for systems that have a fixed location for the valve and where joint hygiene is very important. With a weld joint, there is no problem with degradation of a gasket at the joint, but it makes valve replacement more difficult. ### Flanged Butterfly Valve There are flange arrangements that attach to common flanges on pipes via bolted connections. They suit larger-diameter pipelines and industrial-scale systems where tri-clamp ferrules are not the standard connection. Flanged valves also handle higher pressure ratings than clamp-type designs. ### Threaded Butterfly Valve SMS and ISO thread connections provide a screwed-in fit for pipelines using threaded unions. This configuration is more common in dairy and European processing systems, where SMS threading is the standard. Thread connections are compact and require no clamps or flanges. ### Vacuum Butterfly Valve A vacuum valve is a type of valve that is specifically used when there is a pipeline running under less than atmospheric pressure. Valve seats have different compression mechanisms depending on whether the pressure in the pipeline is positive or negative. Hence, a special design to compensate for this difference is incorporated in the valve seat design. ### Three-Piece and Wafer Butterfly Valves [Wafer valves](https://www.hyflowtech.com/product/wafer-butterfly-valve/) are mounted between two pipe flanges with no separate valve connection ends. Three-piece designs have a removable body section, making it possible to replace the disc and seat without removing the end connections from the piping. Both configurations are used where valve maintenance frequency is a consideration. ## Manual vs Actuated Butterfly Valves Manual butterfly valves use a handle or locking handle to turn the disc by hand. They are suited to low-frequency operation where automation is not needed and where the valve position can be checked visually. Actuated butterfly valves automate the open and close cycle through pneumatic or electric actuators. These are used in automated processing lines where valve positions are controlled by a PLC, triggered by sensors, or integrated into a CIP sequence. ### Pneumatic Actuated Butterfly Valves Pneumatic actuators use compressed air to rotate the disc. They respond quickly and suit high-cycle applications. HEYI’s pneumatic-actuated butterfly valves have been tested to one million cycles, a figure verified through factory performance testing. That cycle count is relevant for production lines running continuous or semi-continuous CIP programs where the valve opens and closes hundreds of times per shift. ### [Electric Actuated Butterfly Valves](https://www.hyflowtech.com/product/electric-actuator-butterfly-valve/) Electric actuators use a motor to control disc position and are suited to applications where a compressed air supply is not available or where precise positioning between open and closed is needed. They integrate with standard control signals including 4-20mA and 24V DC systems. ## Sanitary Butterfly Valves: Valve Seat and Body Materials ### Seat Material The seat is the component most directly affected by process chemicals and cleaning agents. Silicone rubber is the standard seat material for food and pharmaceutical applications, offering FDA compliance and a temperature range suited to hot CIP and steam cleaning cycles. EPDM provides better resistance to caustic cleaning solutions and is preferred in dairy and beverage environments with aggressive sanitizing programs. PTFE-lined seats suit highly corrosive chemical service. ### Body Material [HEYI’s sanitary butterfly valves](https://www.hyflowtech.com/wp-content/uploads/wp-mfa-exports/taxonomy/product_cat/sanitary-butterfly-valves.md) are available in AISI 304 and AISI 316L stainless steel. As noted in earlier articles in this series, 316L is the standard for pharmaceutical, chemical, and chloride-exposed environments. The Ra 0.4 µm interior finish across the valve body meets the hygiene requirements of most food and regulated pharmaceutical applications, with 3A, FDA, and CE certifications covering the compliance documentation. ## Where Sanitary Valves Butterfly Configurations Are Used Tri-clamp and butt-weld butterfly valves control flow on food and beverage filling lines, blending tanks, and CIP circuits. Their low-profile disc creates minimal obstruction in the open position, benefiting high-volume liquid transfer. In pharmaceutical and biotech, actuated butterfly valves are integrated into automated skid systems for reactor feeding, WFI distribution, and solvent transfer. Valve failure during a validated batch carries high cost, which is why the one million-cycle actuator test specification is a meaningful data point for procurement. Dairy and brewing operations use large-diameter flanged and tri-clamp configurations for milk, cream, wort, and beer transfer. Vacuum butterfly valves suit dairy evaporators and brewing vacuum transfer systems. SMS threading ensures compatibility with existing European dairy piping standards. ## Connection Method Comparison | **Type** | **Connection** | **Best Application** | **Key Limitation** | | --- | --- | --- | --- | | Tri-clamp | Clamp ferrule | Food, pharma, dairy. | Lower max pressure than flanged. | | Butt weld | Welded | Fixed hygienic pipelines. | Difficult to remove for maintenance. | | Flanged | Bolt flange | Large diameter, industrial. | Bulkier than clamp designs. | | Threaded | SMS/ISO thread | Dairy, European systems. | Thread wear over many cycles. | | Vacuum | Clamp or weld | Vacuum conveying, freeze drying. | Specialized seat design required. | | Wafer | Between flanges | Space-constrained installations. | Requires full flange disassembly to remove. | [ Contact US ](https://www.hyflowtech.com/wp-content/uploads/wp-mfa-exports/page/contact-us.md)