The working principle of pneumatic valve gas pipeline ball

Basic structure of the
general gas pipeline ball pneumatic valve is mainly by the pneumatic valve, pneumatic valve seat, sphere, pneumatic valve stem and transmission device. The main functions of the pneumatic ball valve is switched on and cutting off the channel of fluid in pipe, pneumatic ball valve is through the transmission device for ball rotation ° to achieve open and close function.
the commonly used gas pipeline ball pneumatic valve mainly has two types: floating ball structure and fixed structure. Pneumatic valve (1) floating ball can be floating spheres under the effect of gas pressure, the ball will be pressed to the export side of the sealing ring, this is to form a single seal, pneumatic valve pneumatic valve seat seal before can't guarantee anything. The structure of the pneumatic ball valve is characterized by simple structure, unilateral sealing performance is good, but its sealing surface stress in a number of large, so the open-close torque. (2) and the fixed structure of the pneumatic ball valve ball with upper and lower axis, the lower shaft is fixed on the bearing at the bottom of the pneumatic valve body, the upper is connected to a pneumatic valve stem. Sphere can be along the vertical axis of rotation, with the passage of pneumatic valve can not like a floating structure pneumatic ball valve ball can move sideways. As a result, the fixed ball ball pneumatic valve, pneumatic valve before the pressure of the fluid to the bearing and pneumatic valve stem, will not cause pressure to the pneumatic valve seat, so fixed pneumatic ball valve torque is small, pneumatic seat deformation is small, stable sealing performance, long service life. Fixed pneumatic ball valve of pneumatic valve seat is floating, floating pneumatic seat with seat after spring pressure and gas pressure sphere, so as to realize seal. Pneumatic ball valve pneumatic valve seat structure
domestic natural gas pipeline is the most commonly used pneumatic ball valve with CAMERON pneumatic ball valve, pneumatic GROVE ball valve, James lai to pneumatic ball valve, zigong pneumatic ball valve, etc. , the most commonly used pneumatic seat structure has the following several forms.
( Ordinary pneumatic seat
commonly used in ordinary pneumatic seat diameter equal to less than the pneumatic ball valve of the mm floating pneumatic seat on [ ] 。 Ordinary pneumatic seat mainly in the pre-tightening force or fluid pressure, pneumatic valve seat and ball pressure, and make the pneumatic seat materials to produce plastic deformation and to seal, the sealing effect depends on the pneumatic seat under the action of fluid, or under the effect of prestressing force can compensation sphere don't roundness and the degree of surface micro roughness. This pneumatic valve seat structure is simple, easy to manufacture, application is more common.
( Elastic pneumatic seat
the elastic pneumatic seat form relatively more, but the commonly used on gas pipeline with helical spring group pneumatic pneumatic valve seat, the seat and disc springs both pneumatic valve seat is by the spring of elastic and fluid pressure pneumatic seat to a sphere, so as to achieve sealing. These two kinds of pneumatic seat has good two-way sealing ability and good elastic compensation ability, but for helical spring group of pneumatic valve seat, every one of the spring stiffness is very difficult to achieve consistent, so that pneumatic seat uneven, influence on the performance of the pneumatic valve seal. Disc spring, by contrast, simple, compact structure, convenient processing, and to receive strength evenly. Therefore is widely applied.
( Rotary pneumatic seat
pneumatic ball valve in the opening moments or shut down before the end of a sphere with pneumatic seat crescent formed between the narrow channel, the gas was throttling and high surge flow turbulent state, often resulted in the erosion of pneumatic valve seat and internal leakage occurred. Rotary pneumatic valve seat is the main characteristics of pneumatic valves in the process of opening and closing, pneumatic valve seat can rotate along the axis of the channel for movement, through the pneumatic valve pneumatic seat rotary switch, can make the pneumatic seat along the circumferential direction even wear, improve the working condition, prolong service life.