conductor integrity management & solutions · 2018-02-12 · 1 safety integrity teamwork trust...

Safety Integrity Teamwork Trust

Conductor Integrity

Management &

Solutions

Delivering safe, reliable,

cost effective solutions to

the North Sea.

Contents 1. Late Life Asset Management

2. Conductors

3. Loadings

4. Internals

5. External

6. Integrity Issues

7. Integrity Issues (2)

8. Integrity Issues (3)

9. What were we dealing with?

10. Analysis

11. Approach by SETS

12. Rope Access Solution

13. Cleaning & Inspection

14. Repair Types

15. Remote Repair

16. Inspection & Install Tooling

17. No Vessel for Subsea Work


1


Late Life Asset Management

• > 150 Fixed Assets in the North Sea at

an average age of 18yrs +

• Beyond field life expectation

• Continued operation in a low $/bbl

environment

• Asset Integrity and Well / Asset Value

balance of utmost importance for

sustainability

• Highest Value Data, gained by

economic methods, allows a

sustainable Integrity management

system


8

Conductors 2

• Asset structural component

• Well load sharing

• Implications for well integrity management

• Environmental sheathing for well casings

• Corrosion protection for surface casing

• Run during early phase operations

• Robust design has permitted field life

extension

• Not necessarily fit for purpose for late life

operations


8

Loadings 3

In service, the conductor is subject to:

• Environmental loading due to waves

and currents

• Impact loads due to contact with

conductor guides

• Operational loads (BOP weight during

work‐over scenarios)

• Corrosive environments


8

Internals 4

• Annuli contents will vary and may not

be understood, especially in older wells

• Surface casing (generally) carries well

load across underwater zone

• Load sharing can be complex and

affected by deterioration of conductor

• Casing integrity – implications for well

barriers to maintain safe operations


8

External 5

Conductors

• Standard heavy walled pipe, typically

26” - 32” diameter

• Spanning between horizontal guide

frames

• Joint connector integrity. Older asset

connectors susceptible to corrosion and

low fatigue life

• Connector structural capacities of

considerable importance

6


Integrity Issues

A few of our favourite things:

• Fretting at guides

• Internal corrosion (@LAT)

• External corrosion (at connectors)

• Connector integrity

• Casing integrity

• Poor subsea inspection

• Poor data management

7


Integrity Issues (2)

1) Fretting, Cracking and through

wall material loss

2) Failed – 60% Circumferential crack

in fretted area running up through

unfretted conductor (now

cleaned)

3) Failed CGF – Through wall defect

and water ingress to surface

casing

8


Integrity Issues (3)

1) Failed Connector in Air Gap,

usually repaired when found with

Structural clamp

2) Failed connector Subsea, requires

more thought and there are

numerous horror stories of repair

attempts

3) Failed connector – Threads appear

to have been machined.

Unknown until conductor pulled as

cleaning proved difficult with

inspection not being on priority list

9


What were we dealing with? Range of fretting noted during ROV flyby

At least 8 Conductors with “heavy fretting” and TWD

Conductor guide bucket damage – multi level

Annuli integrity & at risk?

Splash zone operations so specific levels unknown but some tracking by historical ROV footage

possible.

An Asset which is economic, but borderline as to how fragile that level of economic is.

Marine Growth and access issues impacting any semblance of Asset Integrity requirements or

Risk Based Inspection criteria

“Could we have done something sooner to prevent bigger maintenance spend now?”

10


Analysis

• Understand current condition & determine implications of identified damage

• Build model across all conductors based on current condition and loadings

• Consideration of unique defect situations: separation at guide & connector above


SETS believe, a ‘third eye’ look at any challenge can give a clearer picture to what can be achieved. Our approach is based on Minimising Risk, Maximising Value for all projects, through Early Engagement and

Disruptive Thinking methods. SETS can guide an operator through a Phase stage gate process to de-risk any the project.

ROV/DSV Is not the

only option. SETS approach will ensure all options are considered whether using an ROV , DSV or Rope access technique. We will ensure the focus is on

Minimising Risk, Maximising Value

DSV

£100k/day

a £65k/day £20k/day

r ROV

11

Approach by SETS

r SETS

1

4


Rope Access Solution

• No Vessels – Under deck Rope access deployed solution

• Ability to clean and Inspect material loss within Conductor guide

Frame at circa -15m

• Repeatable, economic method to allow build of Integrity management

solution

• Ability to analyse and advise repair / maintenance requirement from

SETS pre-prepared solutions

12

8


Cleaning & Inspection

1) Cleaning & Inspection Tool Installed in the Airgap to the Conductor by

the Rope Access team

2) The Tool is run down the conductor, cleaning using HP water Jet

nozzles rotating around the conductor

3) The Tool cleans do to and through the Conductor guide frame

4) The Tools attached Laser arm allows the measurement of material loss

due to Fretting down through the guide Frame

13

8


Repair Types

1) Type 1: Is a pretty standard Wear sleeve, for minimal damage and

protection

2) Type 2: Will provide Shear Support were Fretting / TWD has occurred

3) Type 3 / 4: Provides shear & Axial support through guide where this is

not present due to condition

4) Type 5: Where connector has failed, full moment clamp

14

8


Remote Repair

1) Repair Clamp installed in the Airgap by the Rope Access Team

2) SETS Installation Tool interfaced to clamp within the Airgap

3) Clamp & Install Tool Run to Repair Site & Torqued as required

4) SETS Install Tooling detaches from Repair and recovered to surface by

RA Team

15

8


Inspection & Install Tooling 1) Cleaning & Inspection Tool

2) Type 1 Wear Sleeve

3) Type 2 RA install in Airgap

4) Type 2 in location ready for

install

16

14


No Vessels for Subsea works 17


www.setsltd.com

Early engagement. Disruptive thinking.

conductor integrity management & solutions · 2018-02-12 · 1 safety integrity teamwork trust...

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