The strength of the valve performance refers to the valve to withstand the pressure of the media capacity. The valve is a mechanical product that is subjected to internal pressure and must therefore have sufficient strength and rigidity to ensure long-term use without cracking or deformation.
Valve sealing performance refers to the sealing parts of the valve to prevent the ability of media leakage, it is the most important technical indicators of the valve. The sealing part of the valve has three parts: the contact between the opening and closing parts and the sealing surface of the valve seat; the filling of the packing and the stem and the stuffing box; and the connection between the valve body and the valve cover. One of the previous leak is called the internal leakage, which is usually said lax, it will affect the ability of the valve cut off the media. For the cut-off valve class, the internal leakage is not allowed. After the two leaks called leakage, that is, the media leak from the valve to the valve outside. Leakage will cause material loss, pollution of the environment, serious will cause accidents. For flammable and explosive, toxic or radioactive media, leakage is not allowed, so the valve must have a reliable sealing performance.
The media flow through the valve will have a pressure loss (both before and after the valve pressure difference), that is, the valve flow of the media have a certain resistance to the media to overcome the resistance of the valve will consume a certain amount of energy. From the energy conservation considerations, the design and manufacture of valves, as far as possible to reduce the resistance of the valve to the flow medium.
Opening and closing torque and opening and closing torque
Hoisting force and opening and closing torque refers to the valve opening or closing must be applied to the force or torque. When the valve is closed, it is necessary to form a certain sealing pressure between the opening and closing parts and the sealing surface of the opening, and also between the stem and the packing, between the stem and the nut thread, Other friction parts of the friction, which must impose a certain closing force and closing torque, the valve in the opening and closing process, the required opening and closing force and opening and closing torque is changing, the maximum value is closed in the final instantaneous or open The initial moment. Design and manufacture of valves should be designed to reduce their closing force and closing torque.
Opening and closing speed
The opening and closing speed is expressed by the time required to complete the opening or closing operation of the valve. Generally on the valve opening and closing speed without strict requirements, but some conditions on the opening and closing speed have special requirements, if any requirements to quickly open or close to prevent accidents, and some requirements slowly closed to prevent water hammer, This should be taken into account when selecting valve types.
Action sensitivity and reliability
This refers to the valve for the media parameters change, make the appropriate response to the degree of sensitivity. For the valves, valves, valves and other valves used to adjust the parameters of the valve, as well as safety valves, traps and other valves with specific functions, its functional sensitivity and reliability are very important technical performance indicators.
It indicates the degree of durability of the valve, the valve is an important performance indicators, and has great economic significance. Usually to ensure that the sealing requirements of the opening and closing times to represent, can also be used to express the time.