Introduction to the Types and Functions of Valves Equipped on Laboratory Reactors

　　 Laboratory Reactor Manufacturers equip their production processes with a variety of valves, each of which has its own unique characteristics and application areas.

　　1. Gate Valve: A commonly used shut-off valve, it is used to connect or isolate the medium in a pipeline but is not suitable for regulating the flow rate of the medium. Gate valves are typically employed in laboratory reactors where pressure, temperature, and pipe diameter can vary significantly.

　　2. Globe Valve: Also a type of shut-off valve, similar to a gate valve—except that the globe valve is more suitable for smaller-diameter applications.

　　3. A throttling valve controls the pressure and flow rate of a fluid by altering the cross-sectional area of the flow passage. It is a type of regulating valve; however, due to its structural limitations, it lacks the adjustment characteristics of a control valve and therefore cannot be used as a substitute for a control valve.

　　4. A butterfly valve is a type of valve that uses a circular disc, which rotates with the valve stem, as its closing member to perform opening and closing operations. Butterfly valves are primarily used as shut-off valves, but they can also be designed to combine shut-off and throttling functions for flow regulation. Butterfly valves are typically employed in pipelines where the inlet and outlet pressures are relatively low.

　　5. A check valve is a valve that automatically prevents fluid backflow. Under the action of fluid pressure, the valve disc of the check valve opens, allowing fluid to flow from the inlet side to the outlet side. When the pressure on the inlet side drops below that on the outlet side, the valve disc automatically closes under the combined effects of the fluid pressure differential and its own weight, thereby preventing reverse flow. This type of valve is primarily used in applications where it is necessary to stabilize the pressure within a reactor.

　　6. A ball valve is a type of valve that uses a sphere with a circular bore as its closing member. The sphere rotates along with the valve stem to perform the opening and closing action. In laboratory reactors, it is primarily used for discharging liquid materials from the bottom of the reactor.

　　7. A pressure-reducing valve is a type of control valve that reduces the inlet pressure to a desired outlet pressure by throttling through its closing member. Moreover, it can maintain a substantially constant outlet pressure by utilizing the energy inherent in the medium itself, even when the inlet pressure and flow rate fluctuate. Typically, this valve is used in conjunction with a check valve to keep the pressure inside the reactor constant, especially in cases where the pressure changes due to material reactions.

　　8. Steam trap: A valve used in steam pipelines that automatically discharges condensate, air, and other non-condensable gases while preventing steam leakage. Such valves are relatively seldom used in laboratory reactors.