Difference between Globe Valves and Throttle Valves

Globe valve, also called stop valve, is one of the most widely used valves. It is popular because of its durability, easy manufacture, convenient maintenance and low friction between sealing surfaces during opening and closing. It is not only suitable for medium and low pressures, but also suitable for high pressures.

The working principle of the globe valve is to make the sealing surfaces of the disc and the valve close to each other and prevent the medium from flowing, depending on the valve lever pressure.

Stop valves only allow one-way flow of media and have directionality during installation. The face-to-face and end-to-end dimensions of the globe valve are longer than that of the gate valve, and the fluid resistance is large, so the sealing reliability of the valve is not strong in long-term operation. Throttle valve is a valve that controls fluid flow by changing throttle cross-section or choke length. One-way throttle valve can be combined by connecting throttle valve and one-way valve in parallel. Throttle valve and one-way throttle valve are simple flow control valves. In the hydraulic system of fixed displacement pump, throttle valve and overflow valve cooperate to form three throttle modulating velocity systems, namely, in line throttle speed regulating system, return line throttle speed regulating system and bypass throttle modulating velocity system.

Throttle valve has no negative feedback function of flow rate, which can't compensate the speed instability caused by load change. Generally, it is only used for occasions where loads do not change much or speed stability is not high. There is no difference between the appearance of throttle valves and stop valves, except the shape of valve discs. Most discs of throttle valves are conical streamlines, which can adjust the flow and pressure by changing the cross section of the passage. The throttle valve is used to reduce the medium pressure when the pressure drop is extremely large.