Application scope of globe valve
The opening or closing stroke of the stem of the globe valve is relatively short, which has a very reliable cut-off function. The stroke between the opening and closing of American Standard globe valve disc is small, and the sealing surface can withstand multiple opening and closing. Therefore, the globe valve is fit for switching on & off frequently, which can be used in most media process systems. Globe valve is widely used in petrochemical, electric power, metallurgy, urban construction, chemical industry and other industries.
Installation direction of globe valve
The chamfered flat disc is between flat and conical in terms of its shape. If the opening height of the disc is very small and the bottom of the disc is not higher than the seating surface, the formula of conical disc can be used. If the opening height is large, and AK value is close to the data determined by the formula of plane sealing disc, at this time, the opening height of disc shall be calculated according to the distance between the bottom of disc and the seating surface.
When it is viewed from both sides of the globe valve, the downward raised part of the valve stem is “low”. On the other side, the channel connected to the valve chamber slightly higher (relative to “low”) is “high”. Globe valve: DN ≤ 200mm and PN ≤ 4. Globe valve of 0mpa adopts method of low inlet and high outlet. When DN > 200 mm, method of high in and low out should be selected. When the diameter is larger than 200 mm, due to the larger flow rate and the large pressure on the unit area, a large opposite force is needed to ensure the sealing when using the method low inlet and high outlet.
The structure of globe valve body includes straight through type, straight flow type and right angle type. Straight through is the most common structure, but its fluid resistance is the largest. Direct flow fluid has less resistance and is mostly used for fluid with solid particles or high viscosity. The right angle valve body is mostly forged, which is suitable for the globe valve with small diameter and high pressure.
