What is an adjustable choke?
1. n. [Drilling] A valve usually used in well control operations to reduce the pressure of a fluid from high pressure in the closed wellbore to atmospheric pressure. It may be adjusted (opened or closed) to closely control the pressure drop.
How does a wellhead choke valve work?
Choke valves are used to control flow rate and reduce pressure for processing of produced fluids farther downstream. Effective chokes reduce the likelihood of damage to downstream equipment, support longer lasting production timespans, and alleviate stress from field operators by keeping them away from the wellhead.
How do chokes help control well pressure?
Placing a choke at the wellhead means fixing the wellhead pressure and thus the flowing bottom-hole pressure and production rate. For a given wellhead pressure, by calculating pressure loss in the tubing the flowing bottom-hole pressure can be determined.
What does fixed full choke mean?
The oldest way is called a “fixed choke.” Many side-by-side and older single barrels will have fixed chokes, meaning that their barrels have the choke constriction built-in to the end of the barrel at the muzzle end. The barrels of a side-by-side would usually have two different constrictions.
What is a positive choke?
A choke in which the orifice size must be changed to change the rate of flow through the choke.
What is a wellhead choke?
A wellhead choke controls the surface pressure and production rate from a well. Chokes usually are selected so that fluctuations in the line pressure downstream of the choke have no effect on the production rate.
Is the choke supposed to be open or closed?
Normally choke will be in open position, in which valve is parallel to the air flow, and has no effect on the air flow. When choke is actuated by mechanical or by pneumatic method, it rotates an angle restrict the air flow (closed position).
What is surface choke?
In order to control the flow rate of the well at the surface, a surface choke can be installed to control the flow rate of the well. Although a choke device is used for a number of purposes at the surface or downhole, its principal use is to control flow rate and pressure of the produced hydrocarbon at the wellhead.