What is pipeline fittings. How is it applied?

Steel pipeline valves are operating units whose purpose is to regulate and/or control the flow of the working medium in pipeline systems. Depending on the task for which the pipeline is installed, such assemblies provide mixing, shutting off, discharging, regulating or separating the product transported through the pipeline. Regulation is performed by a system of gate valves or valves that change the internal area of the pipe (reduce or block it). Piping valves are divided according to two main operating parameters: nominal (nominal) bore; nominal (nominal) working pressure; Nominal bore (DN) is the index of the inside diameter area of the connection element. This figure is equal to the cross-sectional area of pipes for easy installation of nodes in the pipeline. Available nodes with a diameter of 2.5 mm to 3000 mm. The index of conditional pressure (PN or Ru) gives an understanding of the maximum working pressure of the system at a temperature of the working environment of 20*С, at which the node can be installed. Low pressure valves can be installed on systems with working pressure from 0,1 MPa to 1,5 MPa. Units which may be installed on systems with operating pressure from 10 MPa to 80 MPa are called high pressure valves. The most common nodes are made of steel of such grades as: St20 - carbon steel, which has high strength and ductility; AISI 304 and AISI 306 - stainless steel grades. Such material is the most reliable and ensures long work of control and distribution nodes. Classification of pipeline valves: types, types and purpose By function: shut-off valves - designed for shutting off the flow of transported substances through pipes. They are divided into draining and control valves. The first ensures discharge of working substance, the second - controls the flow of substances in tanks, control and measuring equipment. It includes cocks, valves, shutters, dampers; regulating - controls pipeline operation by means of change of substance flow. Most often there are reducing (throttling) valves. They are designed to control operating pressure in a pipeline system. It is represented by nodes with bore, angle and mixing valves; shutoff-regulating - combines functions of the first and the second. protective (shutoff, cutoff) - is installed on pipelines for protection against emergency changes in working media (sudden pressure or temperature increase). Pipeline valves with shutoff valves, safety and shutoff valves belong to this category; safety valves - works in autonomous mode and makes emergency dump of working media surplus in case of pressure increase in the system. This category includes control and distribution nodes with safety, safety, diaphragm, safety and bypass valves; distribution and mixing - is installed in the nodes of distribution of working media flows or in places where you want them to mix. It includes mixers and nodes with distribution valves; phase separation - designed to separate, for example, steam and steam condensate. That is, substances in different states. 2. According to the principle of control and operation, it can be: controlled (manual or mechanical); valves under remote-actuated drive; autonomous; 3. According to the design of connecting spigots: flanged; coupling; trunnion; fitting; under welding. Application and purpose of pipeline valves Pipeline valves are also classified by application area and are: steam and water - is made of high-quality steel and belongs to the class of high-pressure valves. They are installed on water pipes, water outlets and heating systems operating under high temperature and pressure; gas valves - applied on gas pipes of different diameters for regulation of working pressure in system. It is distinguished by high quality of insulation (laying) to minimize the risk of leaks of gaseous medium transported through the system; oil - installed on oil pipelines and transportation systems of light petroleum products (gasoline, diesel). It is distinguished by high quality of steel and insulation material; energy. Designed for pipelines installed at thermal, nuclear and hydroelectric power plants. The main requirement at the enterprises of such level, of course, is safety. That is why there are especially strict requirements for such units: starting from material quality and ending with operating characteristics; chemical - widely spread at chemical plants. Has a high resistance to various chemicals (acid, nitrogen, etc.). They are made of special steels resistant to aggressive substances; shipbuilding - field of application of such valves is in machinery and shipbuilding. It is characterized by high strength and low