Oil and Gas Well Completions cont 1

Tubing Hanger/Xmas Tree Interface


Adapter Flange

Cross-over between tubing hanger spool and x-mas tree
It can receive the extended tubing hanger neck
Feed through for:
electrical cables (ESP or sensors)
hydraulic controllines (sc-sssv)
sensor lines etc 
Surface Wellhead Connectors





The completed well



Xmas Trees

Primary flow control system for well once in production
Features and access requirements
Outflow from well - production
Inflow to well - injection or killing
Vertical access to tubing - wire line, coiled tubing
Flanged Xmas Tree 
Xmas Tree Components 
Pressure gauges (accessory)
safety hazard / potential wrong pressure readings
Gauge flange or tree cap
provides seal for top of tree
Lubricator valve
isolate pressure, well access for intervention tools
Flow tee
used to direct flow, enable thru-tubing access
Production wing valve
used to isolate well for most routine operations 
Kill wing valve
enables connection of pumping equipment
Choke (accessory)
controls rate of flow from well
Master valves (main isolation valves)
Upper Master Valve (operational valve), optional: hydraulic / pneumatic controlled
Surface Safety Valve
Lower Master Valve (back-up valve)
  manually operated


 X-mas tree valve


¥The stem rotates
¥The gate moves up and down
 
 Choke






Categories of Xmas Tree 

Flanged tree
Several flanged components
each connection is a potential leak path
Much more common than monoblock design
More flexible than monoblock design
takes up more space (height)
Monoblock construction tree
Single block construction
Fewer possible leak paths
Used in high pressure/leak sensitive locations
 
  Monoblock Xmas Tree
 
Comprises inline or "Y" shaped block of single casting/forging
Valving arrangement
Lower Master Valve (manual)
Upper Master Valve (Surface Safety Valve)
Y piece or side outlet flanges
houses both production and kill wing valves
Uppermost valve (manual swab valve)
  Well cluster in shallow water
WELL IN CELLAR


 
 

Tree hook-up
Multiple Completions


Cases where more than one completion string installed
Each string independently suspended
Must seal off tubing casing annulus
either independently or collectively
Independent control of fluid flow in each string
Multiple Completion Tree



Xmas Tree Selection
produce a listing of the parameters of the anticipated process or 
operating envelope
- Classify the Well Type
  Water Well ( low or medium pressure, Rate )
  Oil Well (low, medium or high pressure, GOR, Rate )
  Gas Well ( low, medium or high pressure, WGR, Rate)
This will be the basis for the design and the selection of equipment 
type and rating
 

KEYWORDS
tubing suspension
annulus access
hanger flange
boll weevil
ram type
LMG, UMG, Swab valve
production and kill wing valve
surface safety valve
flanged and monoblock tree
pressure rating
 




Oil and Gas Well Completions