Stop valve is the use of stem lift valve head driven to change the distance between the valve plate and the valve to open and close the control valve, globe valve is the most widely used in chemical production cut-off valve. Globe valve in the actual production is mainly used for water, steam, compressed air and other piping control, but not suitable for viscosity and easy to crystallize the material. Globe valve structure is more complex, but the actual operation is simple and labor-saving, in the regulation of traffic and cut off the channel has a better performance, slow opening and closing rare water hammer phenomenon. Globe valve has the advantages of compact structure and obvious appearance. Hand wheel and valve stem are arranged on the top of the valve. There are threads and stuffing box sealing section in the middle. Globe valve in use to determine the state of the valve opening and closing the main way is to observe the valve stem exposed bonnet height, in order to control the operation of the valve. There may be a gap between the valve stem and the bonnet, which can easily result in media leakage, which can be solved by the packing seal. Small stop valve stem thread located in the valve body, so in use more contact with the media longer, easily corroded by the medium. Therefore, in order to prevent the short life of the globe valve, cents butterfly valve chief engineer Lianquan that the globe valve installation should refer to the direction of the fluid, pay attention to keep pipeline fluid low into the high, that is, from the bottom up through the valve seat. The purpose of this installation is to reduce fluid resistance in the valve body to reduce the valve opening and closing force, while still maintaining the valve stem, the packing box is not in contact with the media to reduce damage and leakage. Globe valve in the installation and use, should pay attention to the following three points: 1, the valve should be opened before the leak check to determine whether the valve without leakage defects, stuffing box is no leak defects. 2, stop valve stem operation, such as can not be done by hand, can use a special F wrench instead, but in the F wrench is still not open, do not use the extended wrench forced open and close, in order to avoid damage to the valve or even safety Accident happened. 3, the cut-off valve used in the medium-pressure steam pipe, the condensate in the open before the need to exclude, after the steam preheating the pipeline, the preheating pressure maintained at between 0.2 to 0.3MPA, the purpose of doing so is to avoid temperature , Sudden changes in pressure caused by the seal damage, after the state is stable to determine the pressure can be adjusted to the desired level.