A butterfly valve regulates flow by rotating a valve plate (butterfly plate). The valve plate can be fully opened or fully closed by rotating 90 degrees around its axis. Its principle is to control the flow rate by changing the relative position of the valve plate and the pipeline.

On the grand stage of industrial production, interlocking is a vital "behind-the-scenes hero" ensuring production safety and improving efficiency. Take automated production lines as an example. These involve numerous complex mechanical devices and processes, requiring close collaboration and orderly operation between various pieces of equipment. The interlocking mechanism acts like a strict commander, ensuring that equipment can only start or perform corresponding operations under specific conditions.

Venturi valves are high-precision flow control valves designed based on the Venturi effect. They are primarily used in fluid systems such as ventilation and air conditioning, and are especially suitable for scenarios with stringent airflow control requirements, such as laboratory fume hoods and clean rooms.

Differential pressure gauges operate based on Bernoulli's theorem and the continuity equation of flow. When fluid flows through a narrow section of a pipe, the increased velocity causes a decrease in static pressure, creating a differential pressure between two points. This differential pressure is converted into deformation by sensitive elements such as rubber diaphragms, and then driven by elastic connectors and magnetic induction devices to rotate the pointer, ultimately displaying the pressure data on the dial.