News and Information
The working principle and characteristics of butterfly valves
A butterfly valve is a type of valve that opens and closes by rotating a disc-shaped plate. Inside the cylindrical passage of the butterfly body, the disc rotates around an axis, typically pivoting 90 degrees. When the flow-control disc reaches this 90-degree position, the valve is fully open, allowing maximum flow. By adjusting the angle of the valve, you can precisely regulate the flow rate of the medium passing through.
Release date:
2021-11-09
I. Working Principle
A butterfly valve is a type of valve that opens and closes by rotating a disc-shaped plate around an axis. In the cylindrical passage of the butterfly body, the disc rotates 90 degrees, allowing precise control of fluid flow. When the flow-control disc reaches the 90-degree position, the valve is fully open, and adjusting the valve angle enables fine-tuning of the media flow rate. Typically, butterfly valves are installed perpendicular to the pipe’s diameter. However, neither the valve body nor the valve stem includes an automatic locking mechanism on their own. To effectively regulate flow, a worm gear reducer is essential. A butterfly valve equipped with a worm gear reducer not only provides automatic locking but also enhances the valve’s operational performance, enabling more accurate adjustments to the media flow rate.
2. Characteristics
(1) Simple in structure and compact in shape. Short in length, small in volume, and lightweight—perfect for large diameters.
(2) Low fluid resistance. When fully open, the valve has a large effective flow area, resulting in minimal fluid resistance.
(3) Easy and quick to open and close, with excellent performance adjustment—capable of turning 90 degrees. It can be fully opened or closed. By adjusting the rotation angle of the disc, you can precisely control the flow rate in layers.
(4) The butterfly disc on both sides of the rotating shaft is essentially aligned with the medium, resulting in a torque direction that minimizes switching torque. Consequently, opening and closing become significantly easier.
(5) Low-pressure valves offer excellent sealing performance, with sealing surfaces typically made from rubber and plastic—materials that ensure reliable tightness. However, butterfly valves are limited by their sealing ring materials, resulting in a narrower range of operating pressures and temperatures. That said, hard-sealed butterfly valves have significantly expanded both their pressure and temperature capabilities.
Related News
The pneumatic pressure regulating valve is a pressure-balanced type, featuring cage-guided operation and a dual-seal design. It is equipped with a multi-spring pneumatic diaphragm actuator, which boasts a compact height, lightweight construction, and easy installation.
2020-04-28
Causes and Prevention of Flashing and Cavitation in Control Valves
Flash vaporization occurs when a non-compressible fluid, after being throttled through a control valve, experiences a drop in static pressure—from the vena contracta section all the way to the valve outlet—until the pressure equals or falls below the fluid’s saturation vapor pressure at the valve inlet temperature. This causes partial liquid evaporation, resulting in a two-phase mixture of gas and liquid downstream of the valve. The onset of flash vaporization leads to a point where the liquid flow no longer increases with further pressure drops, triggering choked flow conditions. Additionally, flash vaporization generates a gas-liquid two-phase flow, with both gas and liquid simultaneously flowing through the valve trim and downstream piping, causing erosion. A distinctive feature of this phenomenon is that the valve trim develops a smooth, polished appearance.
2020-04-28
Design and Selection of Low-Noise Control Valves
Most noise in control valves occurs with compressible fluids, as some of the energy is converted into sound during the throttling process. A common rule of thumb for estimation is this: if the product of the Cv value and the inlet pressure exceeds 1,000, the control valve will generate significant noise under critical pressure drop conditions.
2020-04-28
In recent years, China's valve industry has entered a period of rapid growth, with the barriers to entry in the sector steadily rising. Today, it has become one of Asia's largest valve manufacturing hubs.
2022-07-28
Energy-saving control valve: A Path Toward Lower Energy Consumption
Employing control valves with a low pressure-drop ratio helps reduce the proportion of the valve's pressure drop relative to the system’s total pressure loss, thereby lowering energy consumption. As a result, designing control valves with a low pressure-drop ratio has become one of the key development directions—while another promising avenue is the adoption of low-impedance control valves, such as butterfly valves or eccentric rotary valves. Additionally, self-operated control valves are gaining traction; for instance, directly utilizing the downstream medium’s pressure to create a self-regulating control system, leveraging the controlled medium’s own energy to maintain precise pressure regulation downstream.
2022-01-10
Driven by the "Dual Carbon" strategy, green and low-carbon practices have become the core direction for innovation and development in the valve industry. Energy-efficient, low-emission valve products are rapidly gaining traction, with the related market expected to surpass 30 billion yuan by 2025—representing a robust 27% year-on-year growth and emerging as the industry's new engine for expansion.
2021-11-12
CONTACT
MENCROWN VALVE
Address:Puxi Inducstrial Zone,Oubei Yongjia County, Wenzhou City
Phone:86-577-67379227 67370808 67379222
