Flat gate valve is the main control component of


wellhead and manifold; can also be used
separately as needed. According to its structure can be divided into: manual rising stem
flat gate valve, manual non-rising stem flat gate valve, hydraulic flat gate valve.

Surface safety valve is a special valve whose opening and closing parts are in a normally closed state under the action of external force. When the medium pressure in the equipment or pipeline rises above the specified value, it discharges the medium to the outside of the system to prevent the medium pressure in the pipeline or equipment from exceeding the specified value. The safety valve plays the role of safety protection in the system.

Choke valve is a valve that control fluid flow or pressure by changing the throttle area. The types of choke valve are fixed type, needle type, cage type and orifice type, which adjust the flow and pressure by changing the cross-sectional area of the channel. Usually, the flow rate of the medium between the choke disc and the valve seat is very high, which leads to cavitation on the surface of the choke regulator. In order to minimize cavitation damage, Douson's restrictors are made of materials with excellent cavitation resistance (made of wear-resistant alloy).

Check valve, also known as one-way valve or check valve, its main function is to prevent the reverse flow of the medium, prevent the reverse of the pump and the drive motor, and realize the discharge of the container medium. Check valves can also be used as an auxiliary system for replenishing overpressure pipelines, and are generally installed on kill pipelines or well kill pipelines that require a large flow rate.

Plug valve is a necessary part that is applied to high pressure manifold in well cementing and fracture service, also selected for high pressure fluid control system. It is excellent for its compact structure, easy maintenance, low torque, and rapid operation, which make it to be the most ideal valve for cementing and fracturing manifold.

Compared with the traditional electric valve, the new generation of electric ultra-high pressure valve independently developed by Douson:<br>
Stable torque: Open the valve under the condition of full pressure difference (20000psi), and the torque change is small and uniform in 200 cycle tests. <br>
High adjustment accuracy: The erosion-resistant seat design is adopted, and the adjustment accuracy reaches 1%. <br>
More energy-saving: under the same diameter and pressure level, the new generation of electric valves requires more than 50% less electrical power than traditional electric valves. Small power consumption saves electric energy and also saves the cost of purchasing electric actuators. <br>
High degree of digitalization: each valve in the system can communicate with the user data acquisition system to realize remote control and digital management.