Introduction and Cassification of Choke Valve

Choke valve is the core component of well control device used in choke manifold in oil and natural gas industry. Its function is to maintain a certain casing pressure with the help of its opening and closing during the implementation of oil and gas well pressure control technology, and stabilize the change of bottom hole pressure in a certain narrow range. Most of the throttling elements of the throttle valve adopt needle valve structure; some are cylindrical rubber, whose outer wall is driven by gas and liquid to change the size of its inner hole; others use two overlapping metal plates to change the size of the orifice by their relative rotation. Although the structure of the choke valve is different, the principle is to change the size of the fluid channel so that the resistance of the drilling fluid flowing through the throttle element is different, resulting in different wellhead back pressure. The smaller the through hole is, the greater the back pressure is; the larger the through hole is, the smaller the back pressure is, so as to achieve the purpose of throttling.

The choke valve in the choke manifold are mainly divided into two categories: fixed throttle and adjustable throttle. The adjustable choke valve can be divided into needle throttle valve, barrel choke valve, cage type choke valve and orifice plate choke valve according to the structure of the disc. Its operation modes are manual, pneumatic, electric and hydraulic.

Choke valve is the core component of well control device used in choke manifold in oil and natural gas industry. Its function is to maintain a certain casing pressure with the help of its opening and closing during the implementation of oil and gas well pressure control technology, and stabilize the change of bottom hole pressure in a certain narrow range. Most of the throttling elements of the choke valve adopt needle valve structure; some are cylindrical rubber, whose outer wall is driven by gas and liquid to change the size of its inner hole; others use two overlapping metal plates to change the size of the orifice by their relative rotation. Although the flow rate of the fixed throttle of oil and gas choke valve is fixed, it can be changed according to the needs of different sizes of the throttle to get different displacement. The fixed throttle is used with the adjustable flow valve, usually the adjustable flow valve is used first, and the fixed throttle is used when the kick is large.