Petroleo

Basic Adjustable Gauge Stabilizer Information / Operation for Directional Drillers
Brian Hunt – Global Support Technician

June 30, 2008

© 2005 Weatherford. All rights reserved.

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Why? WHY? WHY?

Didn’t I just learn about motors? Why the **** am I taking this course now?

© 2005 Weatherford. All rights reserved.

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Purpose of an Adjustable Gauge Stabilizer
• TheAdjustable Gauge Stabilizer can be remotely adjusted for oil well drilling simply by engaging and disengaging flow. When circulating, differential pressure across the tool is used to expand or collapse radially moveable pistons. The tool is cycled by turning the flow on and off, and a cam mechanism inside the tool advances to control the various piston positions.

© 2005 Weatherford. All rightsreserved.

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Memorize this for Clients:
• The working diameter of the Weatherford Adjustable Gauge Stabilizer can be remotely adjusted for oilwell drilling. The tool operates hydraulically - differential pressure across the tool is used to expand or collapse radially moveable pistons. A repeatable sequence mechanism controls the desired blade position.

© 2005 Weatherford. All rights reserved.4

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Memorize this for Clients:
• The gauge diameter can be identified from surface pressure signals between 150 to 250 psi. • The tool employs a proven ramp system, using only six large pistons that cover a greater contact area than the nearest competitor. Piston stroke is 1-1/8” (11-1/8” to 121/4”)

© 2005 Weatherford. All rights reserved.

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© 2005 Weatherford. All rightsreserved.

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Purpose of an Adjustable Gauge Stabilizer

© 2005 Weatherford. All rights reserved.

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Purpose of an Adjustable Gauge Stabilizer
• Adjustable Gauge Stabilizer – Internal View

Bottom End

Top End

Choke Housing

Splined Sleeve

Rest Ring

© 2005 Weatherford. All rights reserved.

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Operating Instructions - Cycling
• The cam mechanism cycles betweenthree different positions in a repeated pattern. When the pumps are off, the Adjustable Gauge Stabilizer pistons will be in a neutral position sitting just below the outer surface of the stabilizer blades.

© 2005 Weatherford. All rights reserved.

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Operating Instructions - Cycling
• Depending on the position that the internal cam system is situated at, when the pumps are turned on thepistons will either extend flush with the outer surface of the stabilizer blades, or extend past the stabilizer blades creating a larger diameter stabilizer. The phase that the tool is operating at (Neutral, Open, Closed) will change the build rate on the BHA. The phase in which the Adjustable Gauge Stabilizer is operating in can be determined by reading the standpipe pressure.

© 2005Weatherford. All rights reserved.

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Piston Positions
Pressure Balance Chamber Flow On - Extended

Flow On - Flush

Flow Off - Retracted

© 2005 Weatherford. All rights reserved.

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Operating Instructions - Cycling
• If there is an increase of pressure between 200 and 250 psi when the pumps are on compared to when they were cycled previously, the pistons are in the fully extendedposition. This increase in pressure is directly related to the orifice choke configuration installed in the bottom of the tool before operation. • The chart on the next page summarizes this cycling.

© 2005 Weatherford. All rights reserved.

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Adjustable Gauge Stabilizer “Phase Table”

Phase 1 2 3 4 1 2

Position Neutral Closed Neutral Open Neutral Closed

Piston PositionRetracted Flush Retracted Extended Retracted

Pump Status Off On Off On Off

Pressure Drop None Low None High None

Repeats, Same as Above.

NOTE: This table makes the assumption that the Adjustable Gauge Stabilizer cycles to flush the first time the pumps are started.

© 2005 Weatherford. All rights reserved.

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Choke Sizing Chart for 6-1/8” AGS
6-1/8” AGS CHOKE CONFIGURATION
0.95...