Globe valve is also known as stop valve, is a mandatory sealed valve, so the valve is closed, the valve must be applied pressure to force the sealing surface is not leaking. When the media from the valve below the valve into the valve, the operating force to overcome the resistance is the stem and packing friction and the pressure generated by the medium of the thrust, the force off valve than the valve force, so the stem Of the diameter to be large, or stem bending occurs the top of the fault. According to the connection is divided into three types: flange connection, threaded connection, welding connection. From the self-sealing valve appears, the flow direction of the valve to change from the top of the valve into the valve chamber, then the pressure in the medium under the force off the valve is small, and open the valve force, the stem diameter can be . At the same time, the role of the media, this form of the valve is more stringent. China's valve "three to" has provided that the flow of cut-off valve, all top-down. When the valve is open, the valve opening height, for the nominal diameter of 25% to 30%. Flow has reached the maximum, said the valve has reached the fully open position. So cut-off valve fully open position, the valve should be determined by the stroke.
Globe Valve of the opening and closing part is plug-shaped valve flap, sealing the top surface was flat or sea cone, the valve seat along the centerline of the linear motion. The movement of the valve stem (common name: dark bar), but also lift the rotating rod can be used to control air, water, steam, various corrosive media, mud, oil, liquid metal and radioactive media and other types of fluids flow. Therefore, this type of cut-off valve valve is very suitable for cutting or adjustment and throttling. As the valve stem open or closed stroke is relatively short, and has a very reliable cutting function, and because the change in the valve seat and the valve flap is proportional to the relationship between the stroke is very suitable for the regulation of the flow.