And mark gate two main assembly consists of the summary:

The valve body assemblies and actuators assembly (or actuator system), are divided into four series: single seat series valves, two-seater series valves, sleeve series control valves and self-reliance type series control valves. Four types of valves varieties can lead to many, many different applications, the structure of each structure has its special application, characteristics, advantages and disadvantages. Although some control valve is better than other wider application condition, but control valves and cannot be applied to all of the condition, please you to a control valves sales engineers links to building common enhance performance, reduce cost the best solution. Cast steel and mark gate valve subject to compulsory sealed type, so when valve is closed, must to disc to put pressure on, to have compulsory seal face not leak. When medium by disc below into the valve, operating power need to overcome resistance, and mark gate is stem and packing friction and produced by the pressure of the service medium of the thrust, close the valve open the valve force than force, so stem diameter, or there may be an stem of bending down.

In recent years, since the sealing from appearing, and mark gate to the flow direction of medium is shifted over the disc into the body cavity and, at this point, in the medium pressure effect, shut the valve force is small, but open valve strength is great, the valve stem diameter can reduces correspondingly. At the same time, in the medium function, this form of valve is more closely. And the flow of mark gate, shall be by top down. This valve should be installed horizontally.