1. “Slickline Fatigue Tracking Software Delivers Economic Benefits”
November 14, 2010
ICoTA Round Table
Calgary, AB
Ed Smalley 1

2. Today’s Highlights Drivers for New Slickline Technology
New Technology to Monitor SL Fatigue Life
Slickline fatigue model development
Corrosion life reduction
Slickline Inspection
Example Results

3. Why Focus on Slickline Fatigue Life?
Cost, Safety, and Expand Market
Fatigue Life Monitoring Goals
Extend Life / Reduce SL Expenditures
Improved Safety (SL surface)
Reduce Downtime / Fishing Operations
Increased Customer Confidence in SL Operations

4. Causes of Slickline Failures
Mechanical Damage
Abrasion, severe bending (kinking)
Corrosion
Rust, acid, H2S, CO2
Fatigue Damage
Sheave wheel, overpull
Failure Causes can be Interrelated
- Example: Cracks caused by corrosion can exacerbate fatigue damage
Technology to Quantify both Corrosion & Fatigue Life

5. Slickline Data Acquisition & Fatigue
Data Acquisition System
Acquires depth and weight channels
Display & record data during field operation
Calculates:
Fatigue damage caused by SL movement/tension
Displays:
% Fatigue Life Used vs. length of SL
Slickline history (cuts, re-spooling events, etc.)

6. SL Fatigue Model Development (Fatigue vs. Crack Propagation)
Fatigue Damage
Damage (bending) accumulates until crack initiation
Crack Propagation (following crack initiation)
Repeated bending causes crack propagation until a failure (fracture) occurs
CT Fatigue – includes only crack initiation
DP Fatigue – usually includes only crack propagation
Slickline Fatigue – includes effects of both

7. Large Test Machine (SL Fatigue Model Development)
Air Piston (tension)

8. Large Test Machine (16” and 19” Sheave Diameters)
Each blue sheave actually is 2 sheaves together, one 19” and one 16”. So we can do testing with 2 sheave diameters, but only one drum diameter. The drum has a diameter of 20”.

9. Large Test Machine (Spilt-Drum Used for Testing)
Point out the split drum. When the sample stretches so much that the piston approaches the end of its stroke, we have to stop, release the tension, and rotate one side of the drum, with respect to the other side, to take up the slack.

10. Bending Diameter to Initiate Yielding:
Plastic Fatigue from Bending Events (Bending Strain Inversely Proportional to Sheave Size) d
(in.) Dy
0.092
19.7
0.108
23.1
0.125
26.8
0.140
30.0
Bending Diameter to Initiate Yielding:
Dy = dE σy
Where:
Dy = Bending diameter at which yielding begins
d = Diameter of slickline
E = Modulus of elasticity (30 x 10-6)
σy = cyclic yield stress (~140k PSI typical, varies by material)

11. Strains from a Type 1 SL Rigup (SL Fatigue Model Development)
eSp
eSl
eSu
time
strain
The magnitude of the strains is inversely proportional to the diameter of the sheave (the larger the sheaves the smaller the bending strain and the longer the fatigue life). The reverse strains, shown in red, are the most detrimental, causing the most SL fatigue damage. For this type 1, there are two “strain reversals, which occur at the Sl (lower sheave), one when RIH and one when POOH
RIH
POOH
Sp = power sheave
Sl = lower sheave
Su = upper sheave

12. Strains from a Type 2 SL Rigups (SL Fatigue Model Development)
eSp
eSd1
eSu
eSl
time
strain
Type 2a
eSp
eSd1
eSu
eSl
time
Adding a single depth sheave causes another set of bending events, but the number of strain reversals remains the same – 2.
Type 2b
strain
Sd1 = depth sheave 1

13. Strains from a Type 3 SL Rigups (SL Fatigue Model Development)
eSp
eSd2
eSu
eSl
time
eSd1
Type 3a
eSp
eSd2
eSu
eSl
time
eSd1
Adding a 2 sheave depth system again increases the number of bending events, but again the reverse bends remains at 2, so there is a marginal increase in fatigue damage.
Type 3b
Sd2 = depth sheave 2

14. Model Results / Tension = 0 (SL Fatigue Model Development)
Estimated trips to failure is 1314

15. Model Results / Tension = 2,000 lbs (SL Fatigue Model Development)
Estimated trips to failure dropped to 1046 with tension

16. Corrosion / Tracked Fatigue De-Rating (Portable Slickline Fatigue Tester)
Portable SL Fatigue Test Machine
Wellsite use
Rapid Testing of Short SL Samples
Rotation of SL sample imparts bending strain
Repeatable results
Determine Life Reduction Due to Corrosion
From tests of actual SL being ran in the field

17. Corrosion Life Reduction
Maximum Downhole End:
Hottest corrosive wellbore fluids
Longest period of time in well
Exposure to atmosphere when on drum
Corrosion Testing
Samples taken from downhole end during life of SL
Test samples in portable tester
Compare test results to SL fatigue model
If worse, add a corrosion factor to fatigue results

18. Portable Slickline Tester (Corrosion De-rating & Maximum Remaining Fatigue Life)
Records Revolutions to Failure
Rotation of SL imparts bending events
Convert revolutions to fatigue life
Sample length = 34 cm
Multiple Sheave Sizes
30-61 cm (12-24 in)

19. Sheave Size Adjustment (Portable Slickline Tester)
Adjustable Tailstock Position to Match Sheave Size

20. Fatigue Model vs. Data Comparison (SL Fatigue Model Development) Briden Supa75 0.125”
Everything red and purple is for the small machine.
Everything blue is for the large machine.
The results from the large and small machine agree very well – thus testing with the small machine is sufficient except for high tension testing.
Tests on the small machine with and without cooling were almost the same – thus cooling not needed.
Lines are Tipton’s fatigue model results. The kink in the blue lines at 20” is because the drum of the large machine is always 20”. When the sheaves are below 20” the sheaves dominate the bending. When the sheaves are above 20” the drum dominates the bending.

21. SL Inspection vs. Fatigue Tracking
Inspection Systems Can Locate:
Defects
Cracks or pits
Diameter changes
Necking
Inspection Systems Cannot:
Measure fatigue damage
Estimate SL life reduction due to the defects
Estimate remaining SL fatigue life
The point here is that the SL fatigue life calculation, combined with corrosion tests, should give a much more accurate means of tracking the life of a SL than an inspection system.

22. Slickline Job Data (Example: Tension & Depth vs. Time)

23. % Fatigue Life Used Output (Example)

24. Slickline – Case History 1
Background
Sandvik 2RK ” slickline
Slickline data acquisition system used to record field job data
Depth, tension, sheave size & configuration
Field Data
37 Individual job records (i.e. work on a single well)
Up to 7 downhole trips per well
Slickline History
Time in service: 90 Days

25. Slickline (Case History 1)
Assumptions
Fatigue Calculated as GD31MO 0.108” Slickline
Several Jobs Not Recorded (<10% of total)
Rig Up: Dual-wheeled Measuring Head
Upper & lower sheave wheels (‘Type 3’ rigup)
6 m Slickline Cut Off after Each Job (avg.)
No Exposure to Corrosive Environments

26. Fatigue Calculation (Case History 1)
Tension
Results
Slickline Retired with Only 20% Fatigue Life Used !
Wasted $ for Unnecessary Line Replacement
Fatigue Life Used

27. Conclusion Slickline Fatigue Software Portable Fatigue Tester
Display/record job data
Record line cuts & spooling events
Real-time remaining fatigue life
Can be utilized with DAS provided by numerous manufacturers
Generates post-job customer reports
Portable Fatigue Tester
Test for corrosion
Fatigue life de-rating
Questions?