L4 - X’MAS TREES

• X’MAS TREES

- DUAL BORE TREES

- HORIZONTAL (SPOOL) TREES

- VALVES & ACTUATORS

- DEEPWATER TREES

- ALL ELECTRIC TREE

- DRILL THRU SPOOL TREE

Wellhead to casing hangerMetal Seal assembly

Wellhead to casing hangerMetal Seal assembly

Wellhead to casing hangerMetal Seal assembly

High strength load shoulder

Bypass Area

Passive Pre-loadedlockdown system

13 3/8” casing hanger

10 3/4” casing hanger

7” casing hanger – For Glenelg thetubing hanger is at this elevationand replaces the 7” casing hanger

18 ¾” HP wellhead housing

30” conductor

20” casing

13 3/8” casing

10 3/4” casing

C Annulus

B Annulus

A Annulus

TYPICAL SUBSEA WELLHEAD

H-4 VetcoProfile

Cameron Profile

SUBSEA X’MAS TREE FUNCTIONS • Basically a stack of valves installed on a subsea wellhead to provide a controllable interface

between the well and the production facilities.

• Specific functions of a subsea Christmas tree :

– Sealing the wellhead from the environment by means of the tree connector

– Sealing the production bore and annulus from the environment

– Providing a controlled flow path from the production tubing, through the tree to the production flow line. Well flow control by means of tree valves and/or a tree-mountedchoke valve.

– Providing access to the well bore via tree caps and/or swab valves.

– Providing access to the annulus for well control, pressure monitoring, gas lift, etc.

– Providing a hydraulic interface for the down hole safety valve.

– Providing an electrical interface for down hole instrumentation, electric submersible pumps etc.

– Providing structural support for flow line and control umbilical interface.

Horizontal / Spool TreeConventional Dual Bore Tree

2” Tubing 5 1/2 Tubing

5 1/2, 7”or 9 5/8Tubing

VALVES -PRODUCTION

• Master Control Valve

• Wing Valve

• Swab Valve or Plug

VALVES –ANNULUS

• Control

* Wing Valve

• Swab Valve

CROSSOVER VALVE

TREE VALVES

FAIL SAFE HYDRAULIC ACTUATOR

Gate Valve Slide Bore with Gate in open position

Valve stem moved by hydraulic fluid

Actuator Spring compressed

If hydraulic pressure is lost to the actuator (by design, activated by the control system OR if in an emergency the umbilical is cut) then the spring returns the valve to a safe closed position

Dual Bore X’Tree

• Designed to allow vertical access to the main production bore and to the annulus bore during installation and workover operations.

• When a dual bore subsea Christmas tree is connected to a subseawellhead it must interface with the tubing hanger previouslyinstalled in the wellhead. The tubing hanger and tree must becorrectly orientated so that the production and annulus bores are properly aligned and sealed.

• Accomplished by interaction of a pin and helix between the tubing hanger running tool and the BOP

DUAL BORE TREE

• COOPER CAMERON

• FMC KONGSBERG

• VETCO GREY

• KVAERNER NATIONAL

• DRILQUIP

SUBSEA X’MAS TREE MANUFACTURERS

X’MAS TREE SCHEMATIC WITH CONTROL SYSTEM

Note all control functions pass through the Tree Cap. With Tree Cap removed the control functions can be taken over by a drilling rig.

DUAL BORE X’MAS TREES

DRIL QUIP Showing Protection frameOSENBERG Tree

Horizontal X’Trees• “Side valve tree” or SpoolTree™.

• Most obvious distinction from the dual bore tree: the production and annulus bores branch horizontally out of the side of the treebody /valves on a horizontal axis.

• No production or annulus swab valves. Access to the well bore by removing the internal tree cap, or a wireline plug within the internal tree cap.

• Other distinguishing features of the horizontal tree:

1. the tubing hanger is installed in the tree itself, rather than in the wellhead and

2. the top of the tree is designed so the BOP may be landed onto the tree. This arrangement allows the tubing string to be recoveredwithout first retrieving the tree.

KEY

PWV = PRODUCTION WING VALVE

XOV = CROSSOVER VALV

PMV = PRODUCTION MASTER VALVE

AAV = ANNULUS ACCESS VALVE

AMV = ANNULUS MASTER VALVE

AWV = ANNULUS WING VALVE

SCSSV = DOWNHOLE SUBSURFACE SAFETY VALVE

DHPTT = DOENHOLE P & T TRANSDUCERS

HORIZONTAL TREE5.5” TUBING WITH 4” PRODUCTION CHOKE & 2” GAS LIFT CHOKE

CAMERON HORIZONTAL - SPOOL TREE

TREE PROTECTION

INSTALLATION USING GULDE WIRES

Tree being run on Guide wires from Drilling Rig with Running Tool

DEEPWATER GUIDELINELESS TREE

CAMERON ALL ELECTRIC TREE

1. ELECTRICALLY ACTUATED PRODUCTION GATE VALVE

2. ELECTRICALLY ACTUATED ANNULUS GATE VALVE

3. ELECTRICALLY OPERATED CHOKE

4. ELECTRICALLY ACTUATED CHEMICAL INJECTION VALVE

5. ELECTRIC SUBSEA CONTROL MODULE

6. POWER REGULATION AND COMMUNICATIONS MODULE

RUNNING WELLHEAD AND CEMENTING CASING

Wellhead locked into housing

INSTALLING THE X’MAS TREE

Tree run in drill string using running tool

INSTALLING THE X’MAS TREE

Funnel down capture of tree on wellhead

RUNNING BOP AND TESTING

RUNNING BOP AND TESTING

RUNNING BOP AND TESTING

INSTALLING THE CASING

Drill bit passing through BOP

INSTALLING THE CASING

Drill bit enters top of tree – see tree bore protected by liner

INSTALLING THE CASING

Drill to required depth and retrieve drill