The Relevance of the Most Irrelevant

BHA and Drillstring Component(Why I decided to mess with the conventional blade stabiliser)

Tom Newman

March 10th 2016

Directional Problems

BAT-2 Downhole Dynamics

Poor BHA response, energy transfer & MWD Interference

BHA DamageMWD/LWD, PDM, RSS failures, excessive stabiliser wear

Poor Hole QualityPoor energy transfer, trip time (ledges), csg running issues

Vibration Related Issues

Whirl as Shape

Is a sine wave

Bit tilted by wave, reduces ROP & increases MSE

Shape crosses wellbore = quiet (nodes)

Mechanical Specific Energy best indicator

Source: Fred Dupriest, Thus the Lowly Stabiliser

Fit for Purpose?

Fit for Purpose Solution?

Poor Hydrodynamic Design

Static Flow Modelling Research

Rotational 100 rpm

Flow Modelling Research

Switchblade

Weight Transfer

Hydrodynamic Design

Enhanced Stabiliser

Retention Method Research

Pull and push

Test blade Test boltsTest bolts

Final Retention System

An integral, interference fit pin, with precision radii and a locking bolt array

Run History

Run in Dutch North Sea, UAE, KSA, France, Turkey, and Belgium

Less balling up, stick/slip, vibration & little wear with more stable torque. All other BHA components in good condition.

Wells drilled 20

Hours drilled> 7,000 hrs

Meters drilled> 56,000m / 183,000ft

Case History:

Weight Transfer & Less Balling

Dutch North Sea

OBJECTIVE:16" hole section 659m - 1,566mMotor BHA (1.15° ABH) + 2 x Switchblades 15" & 15 ¼"Build to and hold @ 25˚ inclination

CONCERNS:Packing offBalling

Case History:

Weight Transfer & Less Balling

DRILLING OBSERVATIONS:

No motor stalls

No hanging up

Good tool face control

POOH OBSERVATIONS:

No clay ball problems

No packing off

Fixedblade

Known gauge ODs

Tangent sections

Lower cost applications

Case History:

Weight Transfer & Less Balling

Western Gulf Region

OBJECTIVE:8 1/2" hole section 6,428ft – 9,598ftMotor BHA (1.50° ABH) + 1 x Fixedblade 7 7/8" (8") Hold horizontal with azimuthal left turn @ 27˚

CONCERNS:Sliding ROPTorque levels

Case History:

Weight Transfer & Less Balling

Run Results (Spiralblade vs. Fixedblade)Backflow induced packing off (L0 above)

Minimal surface weight transfer / hang upPOOH No motor stalls

Cross Section Comparison

To see full simulation go to:

https://youtu.be/eRcm44-JVok

Questions?