Single-seat electric control valve imports

? Overview of import control valve 
 Regulating valve for regulating the field of industrial automation process control media flow, pressure, temperature, level and other parameters. According to the automation system control signal, automatically adjust the valve opening, in order to achieve medium flow rate, pressure, temperature and level of regulation. Valve actuator normally or pneumatic actuator and valve body together constitute two parts. Straight trip mainly through single-block and through engine type two, the latter has the flow capacity, imbalances do the characteristics of small and stable operation, it is usually suitable for high flow, high pressure drop and leak less occasions. Rotary are: V-type electric control valve, electric butterfly valve, air control valve, butterfly valve and so on. Flow capacity of Cv value is the main control valve selection of one of the parameters, the control valve flow capacity is defined as: When the control valve fully open, the valve pressure at both ends to 0.1MPa, the fluid density 1g/cm3 per hour flow path control valve of the flow number, called the flow capacity, also known flow coefficient to Cv, said unit t / h, liquid Cv value is calculated as follows. Cv flow capacity value according to the size of look-up table, can determine the control valve nominal diameter DN. In the modern factory automation, the control valve plays a very important role in the production of these plants depends on the liquid and gas flow with the correct distribution and control. These control whether the exchange of energy, stress reduction or simply feeding the container, you need to complete some final control elements. Final control elements can be considered an automatic control of the "physical." Magnitude in the low energy regulator and the implementation of fluid control flow between functions required for high energy level, the final control element to complete the necessary power amplification. 
 ? import control valve flow characteristics 
 Control valve flow characteristics is to maintain a constant pressure differential across the valve under the conditions of the relative medium flows through the valve flow and the relationship between its opening. Control valve flow characteristics are linear features, such as the percentage of properties and characteristics of the three parabolic. Equal percentage control valve, control valve linear characteristic, parabolic valve characteristics. 
 The significance of the three flux characteristics are as follows: 
 (1) the percentage of properties such as (log) 
 Features such as the relative percentage of stroke and not a linear relationship between the relative flow in the stroke unit at each point on the itinerary changes caused by changes in the flow of traffic is proportional to this point, the flow is equal to the percentage change. So it has the advantage of traffic hours, small changes in flow, the flow is large, the flow changes, that is, different openings, and have the same regulation accuracy. 
 (2) linear characteristic (linear) 
 Linearity and the relative stroke linear relationship between the relative flow. Unit change in itinerary changes caused by the flow is constant. Traffic flow, the flow of small changes in relative value, traffic hours, the flow variation in relative value. 
 (3) parabolic characteristic 
 Flows of the two parties in proportion to travel changes, general linear and equal percentage characteristics with intermediate characteristics. 
 From the analysis of the three characteristics can be seen in terms of its regulatory functions to the percentage of properties such as optimal, the regulator stability, regulated performance. The characteristics of parabolic than linear regulation characteristic of good performance, according to applications requirements are different, the selection of any of these flow characteristics. 
 (4) flow coefficient Kv 
 Valve flow coefficient Kv, is an important parameter regulating valve, which reflects the ability of the fluid control valve, that is, the capacity control valve. Kv valve flow coefficient according to the calculation of control valve can determine the caliber of choice. In order to correctly select the valve diameter, valve must be properly rated to calculate the flow coefficient Kv value. Valve rated flow coefficient Kv is defined as: the required conditions, ie, both ends of the valve pressure is 10Pa, the fluid density lg / cm, the rated flow through the valve stroke to m / h or t / h flow number. 
 ? Installation and maintenance of import control valve 
 Regulating valve is very commonly used in industrial production and control equipment of particular importance, it is working properly is directly related to the production of the device is normal or not. Now, with advances in technology, control valve, control valve manufacturer and the very diverse forms, functions are also different, the following highlights the various types of control valve in the installation and commissioning should pay attention to common problems before. 
 1, the regulating valve installed before the purchase incoming inspection test valve is a very important part of the control valve to confirm whether the arrival meet the design requirements. Technical requirements of each valve shall meet the design requirements, but in the incoming inspection should be focused on checking following several contents. 
 2, body / trim size of this element include: valve type, valve type, nominal diameter, valve size, valve core in the form, flow characteristics, leakage levels, body material, valve material, seat material , CV values, the flange sealing surface of the standard form of class size and so on, as long as the same as that which does not match the content and design approval of the design should be identified and recognized. 
 3, part of the implementing agencies should check the contents of the main executive body type, style, function form, spring range, gas pressure. 
 4, part of the contents of locator key locator check the input signal, air pressure, electric and gas source interface size and explosion-proof rating, proof of which shall not be less than the design grade level requirements. 
 5, annex under the control valve design requires careful cleaning of the accessories, such as filtering valves, valve position switches, solenoid valves, hand wheel, special tools. The content of the above tests can clean up, measuring instruments, view the plate as well as specific testing methods (such as flanges and bolts used to identify materials by spectral analysis) and other methods to achieve. 
 6, the control valve body of the hydraulic test pressure test, including the pressure test and spool valve fully closed when the leak test. Typically, when the design pressure of more than 10MPa the control valve, valve pressure test must be carried out to test the body itself and the pressure on the valve cover the situation. 
 American International Group York (USA Yoco International Group) is a global fluid control one of the major production and supply, the company headquarters are located in the U.S. city of Pittsburgh Steel City, the company is committed to research and development of fluid control valves, fluid control production equipment system, in many countries, the production valve base. Users involved in petroleum products, chemicals, electric power, metallurgy, pharmaceutical, food, water treatment, municipal water supply and drainage, gas, paper, electronic industry, building, mechanical equipment and other fields. 

 American International Group York (USA Yoco International Group) mainly imports manufactured products are imported ball valve, gate valve of imports, import butterfly, import cut-off valve, check valve, import control valve, solenoid valve, trap, safety valve of imports, import relief valve, inlet filter, import exhaust valve, the angle seat valve, cut off valve, flame arrester, breather valve of imports, import plug valves, import balance valve, needle valve import import diaphragm and other excellent suppliers. Working pressure 1.0Mpa-42.0Mpa. Operating temperature: -196 ℃ -650 ℃. Material: copper, cast iron, cast steel, carbon steel, WCB, WC6, WC9, 20 #, 25 #, forged steel, A105, F11, F22, stainless steel, 304,304 L, 316,316 L, Cr-Mo steel, cold steel, alloy steel. 
 Distributed in China: Shanghai cents butterfly doors Co., Ltd. 
 Phone :021 -51873926 Contact: Mr. Guo 
 Mobile: 15216666200 
 E-mail: cnyoco@163.com / usa_valve@163.com / shxdfm@163.com 
 Valve: http://www.86fmc.com 
 Valve: http://www.86fmc.net