The design and manufacture of pipeline ball valve The pipeline ball valve is based on the needs of users. In order to meet the requirements of anti-sulfur stress cracking in vulcanized environment, we design, select material, manufacture, test, surface treatment and paint strictly according to American Society of Corrosion Engineers NACE related standards require. The pipeline ball valve series not only have a wide selection of materials, but also use nickel plated or 316 stainless steel as the material of the inner part and a special polymer material for the sealing ring. Alloy steel valves not only anti-corrosion, anti-vulcanization, strong ability, fire, anti-static, good sealing performance, wide range of pressure and temperature, full diameter and diameter are available, and can be equipped with a variety of drive, chemical, petroleum refining System, Natural Gas Extraction and Delivery System Ideal Valve Selection. Pipeline valve for China, it belongs to the golden age, accounting for 1/4 of the world population in China in 2000, long-distance pipeline less than 20,000 km, less than 1% of the global pipeline. Since 2000, it has achieved rapid development. By 2009, it has 80,000 kilometers of long-distance pipelines, accounting for 2.5% of the world total, including 31,000 kilometers of gas transmission lines and 29,000 kilometers of oil transmission lines. Online service of the pipeline ball valve 20000 above. The design and manufacture of pipeline ball valves, the emphasis on safety and reliability, is by no means excessive. And this idea should be implemented in the whole process of ball valve product design, process specifications, parts processing, type testing, product testing, quality control, after-sales service. Whether it is long-distance pipeline or urban pipe network are energy supply lines, is a national economic lifeline. Global underground oil and gas transmission pipelines and pipe networks, like the aboveground transmission and distribution grids, are the basis for the survival of urban industries and civilians. Without this energy supply line, modern urban functions are stopped immediately. 1 body design can be divided into all-welded body design and split body design. All-welded body design has a cylindrical structure and spherical structure, cylindrical structure is a double weld, the heat input during welding large, complex residual stress, axial and radial deformation. Spherical structure is four welded splicing, and now due to advances in technology, the use of left and right body hot forging molding, welding can be welded in the middle, reducing the line energy input and reduce axial and radial deformation. Split structure generally by the valve body and left and right connectors. The connecting body and the valve body are connected by bolts. The thickness of the connecting flange and the connection strength of the bolts should be analogically designed according to the flange with the equivalent diameter of the valve body. The connection strength must prevent the stress of the pipeline from causing loose connection and failing the sealing. Valve body and connector face to face contact with no gap in the middle. Seal must meet the fire safety requirements, the use of rubber O-ring and wound metal gasket combination seal. The material of the valve body is forgings, the temperature above -29C ° is selected from ASTM A105; the following is used from -29C ° to ASTM A350 LF2. For welded bodies, there shall be special restrictions on the chemical composition, carbon content, carbon equivalent, sulfur, phosphorus and other elements of A105 or LF2 materials. Forgings by three standard forgings acceptance, do 100% non-destructive testing, the weld at color inspection and ultrasonic testing. Most of the gas pipeline valve body is the A105, ball A105N. Most of the valve body of the oil pipeline is A105, ball 316. 2 Sealing seat and sealing seat with a combination of sealing structure, the metal-metal initial "seal" to block the entry of solid particles; with rubber, PTFE plastic, nylon, PEEK and other soft seal as a secondary seal to ensure zero leakage . However, due to accidental introduction of foreign matter in the pipeline damage to the soft sealing material, the pipeline ball valve is equipped with emergency sealing agent injection system to obtain temporary sealing requirements. Sealing rubber ring with round, triangular or other special shape. Valve companies have their own design structure and process measures to prevent the rubber ring is blown out during the switching process (Blow out) or cut. For Class900 pounds or more, should be used explosion-proof (AED) characteristics of the material as the O-ring material. PTFE seals, generally cylindrical inlay structure can also be made of barbed combo structure, designed to ensure that the seal is not blown and lead to seal failure. The sealing seat is made of the same material as the valve body, electroless nickel plated and spring-loaded to ensure the initial seal pressure. The spring can be a coil spring, a plate spring or a disc spring made of Inconel X-750. The inlet and outlet seat symmetrical two-way seal design. The piston-type self-sealing medium can be designed as "Single piston action", pressure self-sealing seat structure and Double Piston effect double sealing structure according to customers' requirements. Single-piston effect that is imported seal, the outlet end of the cavity automatically discharge pressure.