GB / T 1048-2005 standard stainless steel valves, valve nominal pressure is also an identity, by a combination of the symbol "PN" and a digital representation of valve manufacturers, can not be used to calculate the nominal purpose, it does not represent the actual measured value of the valve, nominal pressure The aim is to establish specifications to simplify the number of pressure valves, in the selection, design institutes, manufacturing units and users are to follow the principles of this provision to the nearest data by the nominal purpose of the establishment is the same size. Nominal divided European system and the American system. China's nominal pressure is to use the European system standards. Control valve can be a variety of drive valves, such as manual, electric, hydraulic, pneumatic, turbine, electromagnetic dynamic, electromagnetic hydraulic, electro hydraulic, pneumatic and hydraulic, spur gears, bevel gear drive and the like; in pressure, under the effect of temperature or other forms of sensor signals, according to the requirements prescribed action marine valves, or do not rely on the sensor signal and a simple on or off, the valve is being driven or automatic mechanism to open and close member for lifting, sliding, rotating pendulum or rotary motion, thus changing the size of its flow area to achieve its control function. _ Ming Kong plastic valves valve (Online) _ Zhuhai valve by valve, the Hong Kong Science and Technology Co., Ltd. of Dongguan. Valve Co., Ltd., Dongguan Ming Kong (www.gdmgfm.com) is Dongguan, butterfly leaders, over the years, the company implement the scientific management, innovation and development, the principle of honesty and trustworthiness, and satisfy customer needs. Ming Kong valve leadership with the staff warmly welcome all inquiries negotiations to create a better valve out of Hong Kong in the future.