Classification and Characteristics of Oil Well Choke Valves

Ⅰ. Needle choke valve

Needle oil well choke valves are used in choke manifolds, high pressure oil and gas wellhead devices, etc. There are two types of needle throttle valve: manual and hydraulic. Needle throttle valve is mainly composed of flange, valve body, O-ring, packing box, gland, valve stem, handwheel, valve seat, bearing, pressure cap, valve needle, nut, key, etc. A pair of concealed throttle heads and valve seats can reduce the damage caused by high-speed fluids, a large nut on the top cover is convenient for maintenance, and the test port is convenient for installing pressure detection instruments. Needle choke valves are widely used for wellhead systems, manifolds, testing and other purposes.

Ⅱ. Cylindrical choke valve

The valve core of the cylindrical throttle valve is cylindrical and is made of solid carbide; the inner ring of the valve seat is inlaid with cemented carbide; the contact end of the valve cover and the medium is surfacing with cemented carbide, which makes it have good wear resistance and resistance. corrosive. A nylon wear-resistant bushing is embedded in the outlet passage of the valve to protect the valve body from wear.

The cylindrical throttle valve adjusts the opening and closing of the valve flap by hydraulic push or the rotation of the handwheel, and has the characteristics of good fluid flow performance and small vibration. The cylindrical valve disc is fixed on the valve stem by front and rear stop caps, grooved round nuts, etc., and the flow is adjusted with the up and down movement of the valve stem. The valve disc and the inner sleeve of the valve seat are made of YG8, which is resistant to corrosion and erosion. performance.

The cylindrical oil well choke valve is sealed with O-ring and lip-ring between the valve body and the valve cover, the valve body and the liquid cylinder. It is connected with bolts, and the connection part is protruding and away from the inner cavity, which eliminates the erosion of the corrosive medium on the bolts and screw holes, and reduces the bolt load. The manual throttle valve is directly connected with the valve stem by the handwheel to drive the valve core to work. In order to reduce the operating torque, a labor-saving mechanism with a bevel gear structure can also be added between the handwheel and the valve stem.

The tail of the valve cover of the hydraulic cylindrical throttle valve is a hydraulic cylinder and a piston. The hydraulic oil pushes the piston to drive the valve stem, and then drives the valve core to advance forward and backward, so that the flow channel area between the valve core and the valve seat is changed to achieve throttling. Purpose. In order to make the operator of the console know the opening degree of the throttle valve, a valve position transmitter is installed on the outer end of the liquid cylinder of the valve cover.

The throttle valve can only be used to control the pressure and flow, and must not be used as a cutoff, that is, the valve core and the valve seat cannot be used for sealing.

Ⅲ. Cage choke valve

The cage type throttle valve uses the cage structure with holes to change the direction of the fluid, and uses the principle of fluid mechanics to make the fluid move along the center line of the cage to avoid erosion and corrosion of the throttling element and reduce operating noise. The cage type throttle valve can provide a variable flow, and the throttle diameter has a large adjustment range, but if the flow rate is required to remain unchanged, the throttle valve can also provide a fixed flow at a certain position, so that It can meet the different traffic needs of users.