gas valves as well as the classification of the following methods:

By structural features, based off the seat relative to the direction of movement can be divided into: 1 door-shaped DKL fitting cut: off pieces move along the seat center. 2 gate shape: off pieces to move along the vertical seat center. 3 cock and ball: ball plunger or closure member is rotating around the center line itself. 4 Swing type: off pieces around the hydraulic hose ends outside of the valve shaft rotation. 5 dish: off pieces of the disc around the axis of rotation of the valve seat. 6 spool type: sliding closure member in a direction perpendicular to the channel.