The Flowhead is the first piece of equipment on a surface well testing package that handles flow at surface.
When testing a well, surface shut off is usually provided by a flow control head or Flowhead that functions as a temporary Christmas Tree.
The Flowhead is located on top of the well and is the first piece of equipment at the surface that fluid flows through.
Flowhead Functions
The Flowhead Functions:
- It supports the weight of the test string.
- It allows up-and-down and rotation movement of the test string.
- It flows out of the well through a flow valve.
- It allows to pump fluid into the well though a kill valve.
- It allows tools to be introduced into the well through the swab valve.
Flowhead Features and Benefits
The Flowhead has the following features and benefits:
A master valve that allows isolation of the surface equipment from the downholetest string.
A swab valve that permits introduction and retrieval of wireline tools.
A flow line valve to allow fluid to flow from the well. This valve is usually operatedwith a hydraulic actuator, allowing remote and automatic closure.
A kill line valve used to pump fluid into the well.
An optional swivel allowing the test string suspended from the flowhead to berotated independentlyof the main flowhead block.
An elevator sub used to handle the flowhead with the rig elevators.
A threaded connection on top of the elevator sub used to attach pressureequipment.
The only alternative to the Flowhead is the Christmas Tree, whichis a permanent head installed after the well is completed.The Christmas Tree accommodates a completion string.
Because the Flowhead facilitates testing that occurs before a wellis completed, in contrast to the Christmas Tree, it is designed toaccommodate a temporary test string.The threaded connection on the bottom sub allows easyconnection and disconnection of the temporary test string.
Flowhead Subs
Subs above and below the Master and Swab Valve allowhandling of the Flowhead with the rig elevators.They also have a secondary function of protecting thethreads at either end of the Flowhead.Replacement of these Subs is inexpensive compared tothat of the Flowhead Valves.
Flowhead Swivel
The Flowhead Swivel is inserted between the Master Valve and the Main valve block.
It allows the sub-surface equipment to be rotated with respect tothe main Flowhead block.
Using a Swivel, it is possible to rotate the subsurface equipmentwithout disconnecting the flow line or the kill line.
An example of this is using the Swivel to set the Drill Stem Test (DST) packer downhole.
Another example is to re-latch the subsurface connection used with floating rigs.
Contact us: winpetro@hotmail.com
Comentarios