Valve selection steps

Valve is the fluid delivery system is the holding member, with diversion, interception, regulation, throttling, to prevent backflow, shunt or overflow pressure relief effect, pneumatic plastic ball valve. The valve is the main control element of the pipeline. Pipe system is the most suitable selection of the valve is very important, is related to the safety of the pipeline, loss of flow, capital, etc., must be familiar with the characteristics of the valve and the choice of the valve is the steps and basis. At present, pneumatic valve soft butterfly valve, the valve industry in China has been able to produce a full range of gate valves, globe valves, check valves, ball valves, butterfly valves, throttle, plug valves, diaphragm valves, safety valves, regulating valves, traps and special Valves and other 12 categories, pneumatic cut off ball valve; maximum working pressure of 600mpa, the most nominal diameter of 5350mm, the maximum operating temperature of 1200 ℃, the minimum operating temperature of -196 ℃, the utility of water, steam, oil, natural Gas, highly corrosive medium (such as concentrated nitric acid, medium concentration of sulfuric acid, etc.), flammable medium (such as stupid, ethylene, etc.), toxic media (such as hydrogen sulfide), explosive media and with radioactive media Water, etc.), pneumatic valve on the folder. Valve pressure parts made of cast copper, cast iron, ductile iron, high silicon cast iron, cast steel, forged steel, high and low alloy steel, stainless steel, Hastelloy, Inconel, Monel, duplex stainless steel , Titanium alloy, pneumatic butterfly valve. And to support the production of a variety of electric, pneumatic, hydraulic valve drive. The face of so many valve varieties and so complex is the variety of conditions, to choose the most suitable piping system is the installation of the valve products, I think, first of all should be aware of the characteristics of the valve; secondly, should control the choice of the valve is the step and Basis; Furthermore, should follow the principle of choosing the valve is. First, the characteristics of the valve is the use of features and structural characteristics of the use of the valve to determine the characteristics of the important performance and application areas, which are the valve application features are: the type of valve is (closed circuit valves, regulating valves, safety valves, etc.) ; Product type (gate valve, globe valve, butterfly valve, etc.); important valve parts (body, bonnet, valve stem, valve flap, sealing surface) is the information; Structural characteristics It is certainly a trademark of the valve is the installation, repair, maintenance and other means of some structural features, Pan Pan security doors, structural characteristics are: the valve is the length of the structure and the overall height of the pipe is the form of convergence Flange connection, screw connection, clamp connection, male connection, welding connection, etc.), on the security door; sealing surface is the situation (set ring, screw ring, welding, welding, valve body) Rod structure situation (rotating rod, lifting rod) and so on. Second, the choice of the valve steps 1, to understand the valve in the equipment or device is the use of pneumatic threaded ball valve, the valve is sure the working conditions: practical media, working pressure, working temperature, etc. 2, determine the connection with the valve is received The nominal diameter and connection: flange, thread, welding, etc. 3, determine the operation of the valve is the method: manual, electric, electromagnetic, pneumatic or hydraulic, electro-hydraulic linkage 4, according to the pipeline is the medium of transmission, working pressure , The working temperature to determine the selected valve is the shell and the inner is the material: cast steel, carbon steel, stainless steel, alloy steel, stainless steel, gray iron, malleable iron, ductile iron, copper alloy. 5, choose the type of valve is: closed-circuit valves, regulating valves, safety valves, etc. 6, determine the type of valve is: gate valve, globe valve, ball valve, butterfly valve, throttle, safety valve, pressure reducing valve, steam trap 7 , Sure the valve is the parameter: For the active valve, according to the different need to determine the allowable flow resistance, discharge capacity, back pressure, etc., pvc butterfly valve and then determine the nominal diameter of the valve and the valve seat hole is the diameter of 8, Selection of the valve geometry parameters: construction length, the flange connection situation and size, opening and closing the valve height direction is the size of the convergence is the bolt hole size and number of all valve dimensions 9, the application of existing Yes Material: valve product catalog, the valve product samples, and so choose the right valve products Third, the choice of the valve is based on 1, the selected valve is the use of conditions of use and control mode of control 2, the nature of the working medium is: working pressure , Working temperature, corrosion performance, whether it contains solid particles, the media is toxic, whether it is flammable, explosive medium, medium viscosity, etc. 3, the valve Body characteristics are the request: flow resistance, discharge capacity, flow characteristics, sealing grade, etc. 4, the installation size and dimensions requirements: nominal diameter, and the pipe is the connection method and connection dimensions, dimensions or weight restrictions 5, The valve product is an additional request for reliability, service life, and explosion-proof performance of the motorized unit. (When selecting the parameters, it should be noted that if the valve is to be used for control purposes, the following additional parameters must be specified: Operating mode, maximum and minimum Flow requirements, normal flow is the pressure drop, the pressure drop when closed, the maximum and minimum inlet pressure the valve is.) The valve according to the above is based on and steps. When selecting a valve in a fair and accurate manner, it is also necessary to know concretely the internal structure of various types of valves so that the valve that is preferred can be accurately determined. Pipe is the ultimate control is the valve. Valve opening and closing pieces to control the flow of media in the pipeline is the way the valve is the shape of the valve so that the valve has the characteristics of the flow must be in the choice of piping system is the most appropriate installation of the valve is necessary to consider this point. This article Keywords: valve