Key technical performance valves
The strength properties of the valve is the valve's ability to withstand the pressure medium. Withstand the internal pressure of the valve is a mechanical product, and therefore must have sufficient strength and rigidity to ensure the long-term use without the risk of cracking or deformation.
Valve sealing performance is part of the sealing valve to prevent leakage of medium capacity, it is the valve of the most important technical performance indicators. Valve seal has three parts: opening and closing pieces and valve seat sealing surface between the contact points; filler stem and the stuffing of the distribution and handling; valve body and bonnet connection. Of which the first one is called the leakage of internal leakage, also known as loose, it will affect the ability of the valve cut off media. For the truncated valve, internal leakage is not allowed. After two leaks called leak, that media leaks from the valve to the valve outside. Leakage will result in material losses, environmental pollution, can also cause serious accidents. The explosive, toxic or radioactive medium, leakage is allowed, and therefore, the valve must have a reliable sealing performance.
Medium flowing through the valve would cause pressure loss (both before and after the valve pressure difference), that is, the flow valve on the media have a certain resistance, medium to overcome the resistance of the valve is necessary to consume some energy. From the conservation of energy considerations, the design and manufacture of valves, to minimize the resistance of the valve on the flow medium.
Hoisting hoisting force and torque
Opening and closing force and closing torque is open or close the valve must be imposed by force or torque. Close the valve, it is necessary to make opening and closing pieces with fat seat sealing surface seal formed between certain specific pressure, but also to overcome the stem and packing between the stem and the nut thread between the stem end of the Bearing and Other parts of the friction friction, and therefore must apply the closing force and closing moments, the valve opening and closing process, the need to stop force and the opening and closing moments of change, and its maximum is close to the final instant or open the initial transient. Design and manufacture of valves should seek to reduce the closing force and closing moments.
Opening and closing speed
Opening and closing speed is completed with a valve opening or closing action once the time required to represent. Valves open and close speed generally no strict requirements, but some conditions have special requirements for opening and closing speed, if the requirements of rapidly turned on or off, to prevent accidents, and some asked slowly shut down to prevent water hammer, etc., This selection of valve type should be considered.
Action sensitivity and reliability
This refers to the valve for the medium parameters, and make the appropriate degree of sensitivity. The throttle valve, pressure reducing valve, regulating valve is used to adjust the valves and valve medium parameters, the trap has a specific function such as valves, sensitivity and reliability of its function is a very important technical performance indicators.
It represents the durability of the valve is a valve key performance indicators, and has great economic significance. Usually guarantee the sealing requirements to open and close that can also be used to indicate the use of time.