Introduction of high pressure cut-off valve

High pressure cut-off valve opening and closing is plug valve disc, sealing surfaces appear flat or cone, the valve disc make linear movement along the centerline of fluid. Valve stem form of exercise, lifting lever ( The valve rod, hand wheel lifting) And lift rotating lever ( The handwheel with the valve rod rotation movements, nut in the valve body) 。 By the only existing valve opened seated, does not allow for adjusting and throttling. The well-known domestic manufacturers have right valve door equipment co. , LTD. And Shanghai hunan emerging hydropower equipment co. , LTD. The company is the ministry of machine building, chemical, China chemical equipment corporation fixed-point production enterprise. Its products in the industry have a certain price advantage and technological advantages. High pressure cut-off valve belongs to compulsory sealed valve door, so the door is closed, the valve must be pressure on the valve disc, to force a sealing surface does not leak. While the media from the valve disc below to the valve, operating force required to overcome resistance, is the valve stem and packing of the friction force and the thrust produced by medium pressure, close the valve door force than the valve door open force is large, so the diameter of the valve rod, otherwise it will occur the valve rod bending failure. In recent years, from the seal gate valve, globe valve under the valve disc medium flow direction into the valve cavity, above under medium pressure at this moment, close the valve door is small, the force and the force of the valve door open, the diameter of the valve stem can be reduced accordingly. At the same time, under the effect of medium, this form of gate valve is tight. Valve door in China & other; Order to & throughout; Once, as the flow of the valve, shall be applied. High pressure cut-off valve opens, the opening of the valve disc height, is 25% ~ 30% of nominal diameter, flow has reached maximum, said valve door has amounted to full open position. So the cut-off valve in full open position, the valve disc to the trip to decide. Advantages: high pressure cut-off valve has the following advantages: simple structure, manufacture and maintenance more convenient. Working stroke is small, opening and closing time is short. Good sealing, sealing surface friction between the small, long service life. Faults: globe valve faults are as follows: fluid resistance is big, required when opening and closing force is larger. Do not apply to the medium with larger particles, viscosity, easy to coking. Poor regulation performance. High pressure cut-off valve types: high pressure cut-off valve types according to the position of the valve stem threads with external thread type, internal thread type. According to the flow of medium, have straight-through type, straight and Angle. Cut-off valve, the form of the seal packing seal globe valve and bellows seal globe valve. Installation and maintenance: high pressure cut-off valve installation and maintenance should be paid attention to the following: the handwheel, handle operation of cut-off valve can be installed in any position. The handwheel, handle and wei mechanism, does not allow for lifting. The flow of medium should be consistent with the direction arrow shown in the valve body. Globe valves introduction: cut-off valve, also called door and is one of the most widely used valve gate, it is popular, is because of the sealing surface friction between the opening and closing process, more durable, open height is not big, manufacturing easy, convenient maintenance, not only suitable for low voltage, and is suitable for high pressure. It is the closing of the principle, rely on the valve rod pressure, valve valve sealing surface and the valve seat sealing surface fit closely, prevent medium circulation. As a one-way valve only medium flow, the installation direction. The structure length is greater than the gate door, at the same time, fluid resistance is big, long runs, seal reliability is not strong. Globe valves can be divided into three categories: straight through, right Angle type and once-through Angle globe valves.