Definition - What does Fixed Choke mean?
A fixed choke (also known as a positive choke) is a device that is used to control the flow of fluids by directing the flow through a fixed-size hole. The calibration on the choke allows for accurate control over the flow or predetermined fluid rates that have been arrived at in various test conditions.
There are two types of chokes namely, adjustable choke and fixed choke. The adjustable choke allows the fixed choke to be changed during operations and provides greater flexibility for wellbore cleanup rates.
Trenchlesspedia explains Fixed Choke
One type of a fixed choke is the choke bean that is used to control fluid flow. It consists of a replaceable bean usually made of hardened steel. It is mounted near the Christmas tree, which is a set of valves and fittings at the top of a well to control production or flow. The bean is manufactured precisely to the choke diameter and all fluid flows through it. The beans are available in different sizes and are identified by choke diameter. The fixed choke gives more accurate flow control at differing test conditions.
A choke manifold enables dual-flow paths in order to control flow to the downstream process equipment from the upstream control equipment. Choke changes can be done with the least interference to testing and operations. Choke manifold is used in the appraisal well testing, well exploration, extended well testing, production testing, cleanup, and flowback.