Mechanical Cementing Products

The Weatherford Technique

For the last half century, the industry has depended on Weatherford to provide quality equipment for its primary cementing needs. Weatherford now offers the world's largest and most complete line of cementing products - not just a partial solution. As the recognized specialists in the field, Weatherford provides the broadest product offering, innovative tool designs, the latest in manufacturing technology, combined with the backing of experienced engineers to analyze the well and make detailed recommendations for satisfying your cementation objectives. From the beginning of the cementing job to its conclusion, Weatherford provides complete assistance to make sure that job runs properly. Weatherford strives to provide customers with the lowest cementing costs possible.

That's the Weatherford technique.

CONTENTS

Welded Centralizers...................2(inside cover)

Non-Weld Centralizers ...............3(inside cover)®SPIRAGLIDER Centralizers .....4

Centralizers (non-weld) ..............5

Centralizers (welded) .................9

Flow Enhancement Tools ...........14

Roller Centralizers ....................15

Stop Collars ...............................16

Specialty Tools ...........................17

Installation Patterns ...................19

®CentraPro Plus Software Program

The mechanical cementing products installation pattern, as part of the total cementing program, should be based on individual well conditions and operating objectives. To assist in developing the most effective program for a well, Weatherford has developed the CentraPro Plus program, a sophisticated lateral load software program designed to provide optimum deployment of cementation products in the well. This innovative program utilizes three dimensional analysis to calculate the lateral forces as well

Product Testing

Weatherford technicians regularly perform destructive tests to assure that Weatherford products continue to meet the highest standards, exceeding even those of the American Petroleum Institute. Weatherford commitment to the industry involves providing efficient products to meet real well conditions.

Weatherford's main manufacturing plants are licensed to use the API monogram.

Weatherford's specially-designed test procedures monitor products under abnormal conditions.

Weatherford's cementingengineers at the wellsite.

Engineering

Weatherford's experienced cementing engineers are available worldwide to help ensure the correct implementation of the cementing program and the proper installation of each piece of equipment. The on-site engineers continually monitor the well and can quickly adapt the program to unforeseen conditions.

After job completion, Weatherford engineers evaluate the performance data of the well and, by comparing it with other similar cementations, can help customers prepare for future cementing jobs.

1

The Largest and Most Complete Line of

API SPECIFICATION

Centralizers are manufactured for all common casing/hole size combinations...assurance that Weatherford centralizers are of a consistently high quality.

WELDED CENTRALIZERS

INTEGRAL HINGES

Have eight sections and seven shear points for maximum load capacity. Hinges wrap to the inside, against the casing, for optimum design strength.

For Excellent Performance Under Tensile Stress

Weatherford welded centralizers have been providing excellent service for over 50 years. They are the result of high quality materials, coupled with the most advanced manufacturing processes, including proprietary robotics technology and automatic centralizer welding. Consistency is foremost in Weatherford’s goal of assuring performance excellence at the wellsite. Special high strength steel springs are made to design specifications. End collars are uniquely designed with integral hinges and self-locking hinge pins. The centralizer ribs are engineered to maintain rigidity while providing a streamlined profile in the wellbore.

Testing centralizers for stress confirms that they will run under demanding conditions without distortion or destruction.

2

Primary Cementing Tools Found Anywhere

SUPER-STRONG WELDS

And maximum weld length are the product of Weatherford’s patented automatic welding equipment. Assuring ultimate strength and uniformity in every weld.

PREMIUM BOW SPRINGS

High quality spring steel undergoes special heat treatment to achieve maximum centering power and minimum running resistance.

HINGE PINS

Embody a self-locking design that will not work loose, yet they tap easily into place.

ROLL-FORMED RIDGE

Around end collars provide extra rigidity, minimizes out-of-round distortion in shipping or storage, and makes a streamlined leading edge to prevent hanging up.

RIGID QUALITY CONTROL TESTS

Are performed on every centralizer to verify size and fit.

More than 50 years experience has gone into the design, manufacture and continual improvement of the Weatherford non-weld centralizers. Weatherford’s newest generation of products reflects that experience. They are built for use in the most demanding conditions. Starting with the uniformity of the bow hardness to the heavy gauge end collars, they provide a ruggedness for just about any application. These premium products exceed the requirements for API Specification 10D.

Testing centralizers for compression assures that the centralizers can withstand very high forces when running casing. The test, illustrated at left, shows that a damaged centralizer will still remain intact under severe conditions.

EXCEEDS THE REQUIREMENTS OF API SPECIFICATION 10D

With exceptional starting and restoring performance.

EXTENDED PROFILE Prevents bows from hitting against casing collar.

For Excellent Performance While Under Compression

3

NON-WELD CENTRALIZERS

LOCKING TAB

Each bow locks in place securely with patented tab.*

CHOICE OF BOWS

Weatherford offers five basic designs with additional configurations available. The bows can be made in stainless steel and in sizes to match any well profile.

HINGES

Turned inward for maximum strength.

SELF LOCKING HINGE PIN

For easy and sure installation.

HIGH QUALITY BOWS

Uniform bow hardness.

FIELD ASSEMBLY

All bow combinations can be field assembled to reduce shipping costs.

END COLLARS

Non-weld models feature heavy gauge steel with extra strong hinges.

OPTIMIZED HYDRODYNAMICS AND FLOW-BY AREA

Hydrodynamic shape of spiral fins allows optimal mud displacement and minimal pressure drop across centralizer. Induced vortex flows enable superior mud removal.

Typical AverageCoefficient of Friction**

n Zinc Steeln

0.12

0.10

0.08

0.06

0.04

0.02

0.00

Coeffic

ient of F

riction **Valid for water/bentonite,

water/chalk and oil base mud, according to a study by the Institute of Tribology, Technical University of Clausthal, Germany

The Weatherford SPIRAGLIDER centralizers are the newest innovations in a broad offering of cementation products. They were designed specifically for highly deviated or horizontal wells and are ideal for use with liner hangers. The SPIRAGLIDER system consists of a STEEL centralizer and two asymmetrically beveled stop collars.The SPIRAGLIDER centralizer’s unique design features allow them to run in restricted holes while yielding reduced wear and a low coefficient of friction for minimal drag. They promote optimal mud displacement during cementation, utilizing fins that create a vortex motion for superior mud removal. The SPIRAGLIDER construction is tough and gives maximum standoff and wear resistance.

4

PRE-DEFINED FIN LOAD RESISTANCE

SPIRAGLIDERhigh sideloads, yet are engineered to intentionally yield at predetermined sideforce under stuck-pipe conditions.

fin design resists

UNIQUE STOP COLLARS

Provide protection for the centralizer’s leading edge and performs as a positioning device.

SPIRAGLIDER ®

Highly Deviated And Horizontal Well Centralizer System*

STEEL CONSTRUCTION

The SPIRAGLIDER system is made of steel, giving it a toughness advantage over other materials and alloys.

SMOOTH SURFACE

Wide symmetrical fins are smoothly beveled on both ends to have lower coefficient of friction and to ease casing movement in either direction.

SHAPED TO MINIMIZE RUNNING RESISTANCEBoth spiral and straight fin designs minimize drag forces while running pipe. The fins glide smoothly on the low side of horizontal boreholes.

in. mm in. mm in. mm in. mm

4" ST A0 6.186 157.1 4.965 126.1 10-3/4" ST A0 13.010 330.5 11.790 299.5

ST A1 6.579 167.1 5.201 132.1 ST A1 13.404 340.5 12.026 305.5

ST A2 7.131 181.1 5.201 132.1 ST A2 13.955 354.5 12.026 305.5

ST A3 8.902 226.1 5.201 132.1 ST A3 15.727 399.5 12.026 305.5

ST A4 10.398 264.1 5.201 132.1 ST A4 17.223 437.5 12.026 305.5

4-1/2" ST A0 6.691 169.9 5.470 138.9 11-3/4" ST A0 14.023 356.2 12.802 352.2

ST A1 7.084 179.9 5.706 144.9 ST A1 14.417 366.2 13.039 331.2

ST A2 7.636 193.9 5.706 144.9 ST A2 14.968 380.2 13.039 331.2

ST A3 9.407 238.9 5.706 144.9 ST A3 16.739 425.2 13.039 331.2

ST A4 10.903 276.9 5.706 144.9 ST A4 18.235 463.2 13.039 331.2

5" ST A0 7.196 182.8 5.975 151.8 13-3/8" ST A0 15.668 398.0 14.448 367.0

ST A1 7.589 192.8 6.211 157.8 ST A1 16.062 408.0 14.684 373.0

ST A2 8.141 206.8 6.211 157.8 ST A2 16.613 422.0 14.684 373.0

ST A3 9.912 251.8 6.211 157.8 ST A3 18.385 467.0 14.684 373.0

ST A4 11.408 289.8 6.211 157.8 ST A4 19.881 505.0 14.684 373.0

5-1/2" ST A0 7.701 195.6 6.480 164.6 16" ST A0 18.326 465.5 17.106 434.5

ST A1 8.094 205.6 6.716 170.6 ST A1 18.720 475.5 17.342 440.5

ST A2 8.646 219.6 6.716 170.6 ST A2 19.271 489.5 17.342 440.5

ST A3 10.417 264.6 6.716 170.6 ST A3 21.043 534.5 17.342 440.5

ST A4 11.913 302.6 6.716 170.6 ST A4 22.539 572.5 17.342 440.5

6-5/8" ST A0 8.837 224.5 7.616 193.0 18-5/8" ST A0 20.984 533.0 19.763 502.0

ST A1 9.231 234.5 7.853 199.5 ST A1 21.377 543.0 20.000 508.0

ST A2 9.782 248.5 7.853 199.5 ST A2 21.929 557.0 20.000 508.0

ST A3 11.553 293.5 7.853 199.5 ST A3 23.700 602.0 20.000 508.0

ST A4 13.050 331.5 7.853 199.5 ST A4 25.196 640.0 20.000 508.0

7" ST A0 9.216 234.1 7.995 203.1 20" ST A0 22.376 568.4 21.156 537.4

ST A1 9.609 244.1 8.231 209.1 ST A1 22.770 578.4 21.392 543.4

ST A2 10.161 258.1 8.231 209.1 ST A2 23.321 592.4 21.392 543.4

ST A3 11.932 303.1 8.231 209.1 ST A3 25.093 637.4 21.392 543.4

ST A4 13.428 341.1 8.231 209.1 ST A4 26.589 675.4 21.392 543.4

7-5/8" ST A0 9.847 250.1 8.626 219.1 24" ST A0 26.426 671.2 25.206 640.2

ST A1 10.241 260.1 8.863 225.1 ST A1 26.820 681.2 25.442 646.2

ST A2 10.792 274.1 8.863 225.1 ST A2 27.371 695.2 25.442 646.2

ST A3 12.563 319.1 8.863 225.1 ST A3 29.143 740.2 25.442 646.2

ST A4 14.060 357.1 8.863 225.1 ST A4 30.639 778.2 25.442 646.2

8-5/8" ST A0 10.857 275.8 9.636 244.8 26" ST A0 28.451 722.7 27.231 691.7

ST A1 11.251 285.8 9.873 250.8 ST A1 28.845 732.7 27.467 697.7

ST A2 11.802 299.8 9.873 250.8 ST A2 29.396 746.7 27.467 697.7

ST A3 13.573 344.8 9.873 250.8 ST A3 31.168 791.7 27.467 697.7

ST A4 15.070 382.8 9.873 250.8 ST A4 32.664 829.7 27.467 697.7

9-5/8" ST A0 11.867 301.4 10.646 270.4 30" ST A0 32.501 825.5 31.281 794.5

ST A1 12.261 311.4 10.883 276.4 ST A1 32.895 835.5 31.517 800.5

ST A2 12.812 325.4 10.883 276.4 ST A2 33.446 849.5 31.517 800.5

ST A3 14.583 370.4 10.883 276.4 ST A3 35.218 894.5 31.517 800.5

ST A4 16.080 408.4 10.883 276.4 ST A4 36.714 932.5 31.517 800.5

Casing Size

(in.)Bow Type

Maximum O.D. Min. Compressed O.D.Casing Size

(in.)Bow Type

Maximum O.D. Min. Compressed O.D.

STRAIGHT BOW CENTRALIZERS

Weatherford’s non-weld straight centralizers are the result of more than 50 years of field experience and laboratory testing. This newest design has features making them ideal for both tubing and casing applications.

Non-Weld Straight Centralizers

NON-WELD STRAIGHT CENTRALIZER BOW HEIGHTS

5

NON-WELD CENTRALIZERS

Weatherford markets straight centralizer bows in several standard sizes and provides a variety of bow configurations for special applications. If your well plan requires a special design, contact your local Weatherford representative.

?Non-weld design eliminates weak spots.

?Choice of standard bow heights assures optimum starting/restoring force criteria.

?Patented locking tabs hold bows in the collars.

?High-quality, spring-steel bows and specially designed collar hinges provide reliable downhole performance.

?Available in stainless steel.

STA0 STA1 STA2 STA3 STA4

In. 0.965 1.161 1.437 2.303 3.051

mm 24.5 29.5 36.5 58.5 77.5

Non-Weld Centralizer Standard Bow HeightsStraight Centralizer Bow Configurations

STA 0 STA 1 STA 3 STA 3 STA 4

PipeOD

Height

TANDEM RISE™ BOW CENTRALIZERS

This special design increases the ratio of restoring force to moving force. It has the ability to withstand high lateral loads encountered in horizontal holes. The non-weld design increases its ability to withstand compressive loading while running in the wellbore. It is available for close tolerance applications and can be installed over casing couplings and stop collars.

Benefits include:

NON-WELD STRAIGHT CENTRALIZERS – TUBING

Tubing centralizers can be effective in tubingless completions, for guiding and stabbing tubing into downhole equipment or in reducing frictional drag in deviated holes. They can also be used to center wireline tools, to protect control lines and cables, or to prevent wear on tubing and casing due to thermal expansion and contraction. For optimum tubing concentricity, Weatherford recommends the use of positive tubing centralizers inside casing.

TR 2

TR 3

TR 4

* When bows are completely compressed, these figures represent the centralizer’s largest rigid diameter presented by the bow, the hinge or any other part.

NOTE: STI AND STII centralizers should not be installed over any casing collar or stop collar.

NON-WELD STRAIGHT CENTRALIZERS – TUBING

Tandem Rise Bow Profiles

6

NON-WELD CENTRALIZERS

?Better standoff for increased mud removal

?Reduced drag while running pipe

?Reduced wall sticking for easier pipe movement

?Increased contact area for less bow penetration into the formation

?Complete mud removal while cementing

in. mm in. mm in. mm

TR1 0.171 4.35 0.8 20.32 14-1/8" 358.8*

TR2 0.171 4.35 1.171 29.74 14-1/8" 358.8

TR3 0.171 4.35 1.421 36.09 14-1/8" 358.8

TR4 0.171 4.35 2.171 55.14 14-1/8" 358.8

Note: 1) All bows 1-1/2" (38.1 mm) wide

*Based on 5/8" clearance for coupling

Bow

Spring

Number

"X" Bow

thickness"X" Bow Height

"Z" Max. Coupling

Length

Based on Coupling 1"

Above Casing Size

in. mm in. mm

2-3/8" STTI 5-1/8" 130 3-3/8" 86

STTII 5-1/2" 140 3-1/2" 89

STTIII 7-1/4" 184 3-1/2" 89

STTIV 8-1/2" 216 3-1/2" 89

2-7/8" STTI 5-5/8" 143 3-7/8" 98

STTII 6" 153 4" 102

STTIII 7-3/4" 197 4" 102

STTIV 9" 229 4" 102

3-1/2" STTI 6-1/4" 159 4-1/2" 114

STTII 6-5/8" 169 4-5/8" 117

STTIII 8-3/8" 213 4-5/8" 117

STTIV 9-5/8" 245 4-5/8" 117

Size (in.) Bow TypeMaximum Bow O.D.

Minimum Compressed Bow

O.D.

TR 1

ZX Y

Non-WeldPositive Centralizer

Non-Weld Positive Centralizers – Casing

BOW SPRING CENTRALIZERS

The Bow Spring Centralizer Sub meets the demands of ultra-tight clearance casing strings. Where special drilling requirements demand that casing be run in previous casing or open hole with close tolerances, this tool allows passing very tight restrictions, followed by expansion into an under reamed hole. The Bow Spring Centralizer Sub offers numerous advantages, including:

POSITIVE CENTRALIZERS

Weatherford’s non-weld positive centralizers are available for both tubing and casing applications. They significantly reduce frictional drag when used in deviated holes, and can provide nearly 100 percent standoff (concentricity) when run inside a cased hole.

Concentric casing strings facilitate liner and packer positioning, stage cementing, surface cementing, slip and packoff installation, and well-abandonment. Weatherford’s non-weld positive centralizers offer the following features:

*Special Tools Available 16” - 24”

BOW SPRING CENTRALIZER SUB

Bow Spring Centralizer SUB*

7

NON-WELD CENTRALIZERS

?Combines slim hole capabilities with the quality of Weatherford’s welded centralizers

?Runs inside ultra-tight clearances

?Centralizer bows recess completely into tool body then expands for casing centering in open or underreamed sections

?Allows maximum fluid bypass area to minimize the impact on circulating pressure

?Non-weld design eliminates weak (brittle) spots

?U-profile bow design permits maximum fluid passage.

?Available with solid bows.

?Patented locking tabs hold bows in the collars

?Can be transported unassembled to reduce

?Large selection of bow sizes, shipping costs.

Casing

Size*

Previous

Casing Min.

Drift I.D.

Open Hole Size

Number of

Bow

Springs

4.500 5.000 5-3/4" - 9-7/8" 4

5.000 5.500 6" - 10-5/8" 4

5.500 6.000 6-1/2" - 10-5/8" 4

7.000 7.500 7-7/8" - 12-1/4" 4

7.625 8.125 8-1/2" - 12-1/4" 6

8.625 9.125 9-5/8" - 12-1/2" 6

9.625 10.125 10-1/2" - 14-3/4" 6

10.750 11.250 12-1/4" - 15-1/2" 6

11.750 12.250 13-1/2" - 16" 6

13.375 14.000 14-3/4" - 17-1/2" 8

in mm in mm in mm in mm in mm in mm in mm in mm in mm in mm in mm

4" 5-1/8" 130.2 5-1/2" 139.7 5-7/8" 149.2 6-1/8" 155.6 6-1/8" 165.1 6-7/8" 174.6 7-1/4" 184.2 7-5/8" 183.7 8-7/8" 225.4 10-3/8" 263.5 5-7/8" 149.2

4-1/2" 5-5/8" 142.9 6" 152.4 6-3/8" 161.9 6-5/8" 168.3 7" 203.2 7-3/8" 187.3 7-3/4" 196.9 8-1/8" 206.4 9-3/8" 238.1 10-7/8" 276.2 6-3/8" 161.9

5" 6-1/8" 155.6 6-1/2" 165.1 6-7/8" 174.6 7-1/8" 181.0 7-1/2" 190.5 7-7/8" 200.0 8-1/4" 209.6 8-5/8" 219.1 9-7/8" 250.8 11-3/8" 288.9 6-7/8" 174.6

5-1/2" 6-5/8" 168.3 7" 177.8 7-3/8" 187.3 7-5/8" 193.7 8" 228.6 8-3/8" 212.7 8-3/4" 222.3 9-1/8" 231.6 10-3/8" 263.5 11-7/8" 301.6 7-3/8" 187.9

6-5/8" 7-3/4" 196.9 8-1/8" 206.4 8-1/2" 215.9 8-3/4" 222.3 9-1/8" 231.8 9-1/2" 241.3 9-7/8" 250.8 10-1/4" 260.4 11-1/2" 292.1 13" 355.6 8-1/2" 215.9

7" 8-1/8" 206.4 8-1/2" 215.9 8-7/8" 225.4 9-1/8" 231.8 9-1/2" 241.3 9-7/8" 250.8 10-1/4" 260.4 10-5/8" 269.9 11-7/8" 301.6 13-3/8" 339.7 8-7/8" 225.4

7-5/8" 8-3/4" 222.3 9-1/8" 231.8 9-1/2" 241.3 9-3/4" 247.7 10-1/8" 257.2 10-1/2" 266.7 10-7/8" 276.2 11-1/4" 285.8 12-1/2" 317.5 14" 381.0 9-1/2" 241.3

8-5/8" 9-3/4" 247.7 10-1/8" 257.2 10-1/2" 266.7 10-3/4" 273.1 11-1/8" 282.6 11-1/2" 292.1 11-7/8" 301.6 12-1/4" 311.2 13-1/2" 342.9 15" 406.4 10-1/2" 266.7

8-5/8" 10-3/4" 273.1 11-1/8" 282.6 11-1/2" 292.1 11-3/4" 298.5 12-1/8" 308.0 12-1/2" 317.5 12-7/8" 327.0 13-1/4" 338.6 14-1/2" 368.3 16" 431.8 11-1/2" 292.1

10-3/4" 11-7/8" 301.6 12-1/4" 311.2 12-5/8" 320.7 12-7/8" 327.0 13-1/4" 336.6 13-5/8" 346.1 14" 381.0 14-3/8" 365.1 15-1/2" 393.7 17-1/8" 435.0 12-5/8" 320.7

11-3/4" 12-7/8" 327.0 13-1/4" 336.6 13-5/8" 346.1 13-7/8" 352.4 14-1/4" 362.0 14-5/8" 371.5 15" 406.4 15-3/8" 390.5 16-1/2" 419.1 18-1/8" 460.4 13-5/8" 346.1

13-3/8" 14-1/2" 368.3 14-7/8" 377.8 15-1/4" 387.4 15-1/2" 393.7 15-7/8" 403.2 16-1/4" 412.8 18-5/8" 422.3 17" 457.2 18-1/4" 463.6 19-3/4" 501.7 15-1/4" 387.4

16" 17-1/8" 435.0 17-1/2" 444.5 17-7/8" 454.0 18-1/8" 460.4 18-1/2" 469.9 18-7/8" 479.4 19-1/4" 489.0 19-5/8" 496.6 20-7/8" 530.2 22-3/8" 568.3 17-7/8" 454.0

18-5/8" 19-3/4" 501.7 20-1/2" 511.2 20-1/2" 520.7 20-3/4" 527.1 21-1/8" 538.8 21-1/2" 546.1 21-7/8" 555.6 22-3/8" 568.3 23-1/2" 596.9 25-1/8" 638.2 20-1/2" 520.7

20" 21-1/8" 536.6 21-7/8" 546.1 21-7/8" 555.6 22-1/8" 562.0 22-1/2" 571.5 22-7/8" 581.0 23-1/4" 590.6 23-3/4" 603.3 24-7/8" 631.8 26-1/2" 673.1 21-7/8" 555.6

24" 25-1/8" 638.2 25-1/2" 647.7 25-7/8" 657.2 26-1/8" 663.6 26-1/2" 673.1 27" 711.2 27-3/8" 695.3 27-3/4" 704.9 28-7/8" 733.4 30-1/2" 774.7 25-7/8" 657.2

PO9 PO10 PO11Size (in.)

Bow Type / Maximum Box O.D.

PO1 PO2 PO3 PO4 PO5 PO6 PO7 PO8

Restoring Force

Test Positions

CENTRALIZER SELECTION

To select the right product for application, basic considerations need to be examined.

To help achieve the proper balance between starting force and restoring force, Weatherford offers centralizers with a wide range of bow heights and shapes as well as one piece aluminum rigid centralizers for deviated and horizontal wells.

The restoring force is the force exerted by a centralizer against the casing to keep it away from the bore hole wall. Current API Specification 10D states that "67% may or may not be sufficient for a good cementation." Practical experience has shown that standoff values of 75 to 90% are adequate, even in horizontal wells.

Restoring Force TestAccording to API SPEC 10D

Starting Force and Moving(= Running) Force Testaccording to API SPEC 10D

F = Measured Starting and Running ( = Moving) Force

W = Weight of 40 feet medium weight casing

The starting force is the maximum force required to start a centralizer into previously run casing. It should be less than the weight of 40 feet (12.2 meters) of medium weight casing.

Centralizers for other casing and hole combinations available upon request. - Chart does not apply to Bow Spring Centralizers Subs

BOW SPRING SELECTION GUIDE NON-WELD CENTRALIZERS

F < W

8

NON-WELD CENTRALIZERS

Casing

Size (in.)

Bow

Type

Preferred Hole Size Combination

(in.)

Casing Size

(in.)

Bow

Type

Preferred Hole

Size

Combination

(in.)

4" ST A0 -- 10-3/4" ST A0 12-1/4"

ST A1 -- ST A1 12-1/4"

ST A2 6-5/8" ST A2 12-5/8"

ST A3 -- ST A3 13-1/2"

ST A4 -- ST A4 14-3/4", 15-1/2"

4-1/2" ST A0 6", 6-1/8", 6-1/4" 11-3/4" ST A0 --

ST A1 6-1/2", 6-3/4" ST A1 --

ST A2 -- ST A2 13-1/2"

ST A3 8-1/2", 8-3/4" ST A3 12-3/4", 15-1/2"

ST A4 9-7/8", 10-5/8" ST A4 17-1/2"

5" ST A0 6-1/4", 6-1/2" 13-3/8" ST A0 --

ST A1 6-3/4" ST A1 14-3/4"

ST A2 -- ST A2 15-1/2"

ST A3 8-1/2", 8-3/4" ST A3 16"

ST A4 10-5/8", 11" ST A4 17-1/2"

5-1/2" ST A0 6-5/8", 6-1/2", 6-3/4" 16" ST A0 17-1/2"

ST A1 -- ST A1 --

ST A2 7-1/8" ST A2 18-1/2"

ST A3 8-3/8", 8-1/2", 8-3/4", 9-7/8" ST A3 18-1/2"

ST A4 10-5/8", 11" ST A4 20", 22"

6-1/2" ST A0 7-7/8" 18-5/8" ST A0 --

ST A1 8-1/2", 8-5/8" ST A1 --

ST A2 8-5/8", 8-3/4" ST A2 --

ST A3 10-5/8", 11" ST A3 22"

ST A4 12-1/4" ST A4 24"

7" ST A0 8-3/8", 8-1/2" 20" ST A0 --

ST A1 8-1/2", 8-5/8", 8-3/4" ST A1 --

ST A2 8-1/2", 8-5/8", 8-3/4" ST A2 22"

ST A3 10-5/8", 11" ST A3 --

ST A4 12-1/4" ST A4 24", 26"

7-5/8" ST A0 -- 24" ST A0 --

ST A1 9-1/2" ST A1 --

ST A2 9-7/8" ST A2 26"

ST A3 12-1/4" ST A3 --

ST A4 13-1/2" ST A4 28"

8-5/8" ST A0 9-3/4", 9-7/8" 26" ST A0 --

ST A1 10-5/8" ST A1 --

ST A2 -- ST A2 --

ST A3 12-1/4" ST A3 --

ST A4 13-1/2" ST A4 30", 32"

9-5/8" ST A0 -- 30" ST A0 --

ST A1 11" ST A1 --

ST A2 11-3/8" ST A2 --

ST A3 11-3/4", 12-1/4", 12-1/2", 12-5/8" ST A3 32"

ST A4 14-3/4", 15-1/2" ST A4 34", 36"

Product Numbers :11216 Latch-on with lap-welded bows.

:12212 Latch-on with notched-bows

:12312 Slip-on with notched-in bows

9

WELDED CENTRALIZERS

S-SERIES CENTRALIZERS

The Weatherford S-Series centralizer is the standard welded centralizer for casing-hole size combinations and is a high quality welded product that meets or exceeds API Specification 10D requirements. It offers a choice of six different bow heights, available for any casing/open hole configuration. The end collars are available as latch-on or slip-on. The S-Series features:

?Rigid Design - End bands are equipped with ribs to provide rigidity to the bands. Bow springs are of high quality heat-treated spring steel.

?Integral Hinge - Folded to the inside of the endbands so that, once installed, it won't unfold even under extreme conditions.

?Self-Locking Hinge Pins - Equipped with a positive safety locking device.

?Clearance - Since bow springs are attached to the O.D. of the end collars, the centralizers may be installed over stop collars or casing collars.

Product Number: S110 _ _ Latch-On.

Available bow springs: 25, 30, 36, 46, 57 and 85.

B-SERIES CENTRALIZERS

Some hole conditions do not require the same superior performance characteristics of the S-Series. In these instances, the B-Series centralizers offer an economical alternative. They are manufactured in a broad range of hole sizes and may be installed over the casing collars or stop collars.

Product Number: B110 _ _ Latch-On

Available bow springs: 25, 36 and 46.

SINGLE LINER CENTRALIZERS

These centralizers are specifically designed for close tolerance applications where running drag must be minimal, yet the centering strength as high as possible. The uniquely-shaped bows accomplish this most effectively, making these centralizers the optimum solution.

?Available in Turbolizer styles

?Available as latch-on or slip-on

?Notched or lap-welded versions available

?Furnished with integral set screws

?Can be installed without set screws, between stop collars, for casing rotation.

The Turbolizer centralizer's fluid motion causes:

SINGLE STRAIGHT (TURBOLIZER) CENTRALIZERS

DOUBLE REVERSE BOW TURBOLIZER CENTRALIZERS

10

WELDED CENTRALIZERS

TURBOLIZER™ CENTRALIZERS

Weatherford Turbolizer centralizers have all of the characteristics of regular centralizers as far as starting and restoring forces are concerned. The main difference is that the Turbolizer centralizers have a built-in stop collar and deflector blades. These blades, or fins, deflect the fluid flow in a turbulent and outward directed spiral.

?Choice of bow spring and deflector fin sizes

?Equipped with right or left handed fins

?Have integral set screws

?Meet API Specification 10D requirements in most casing and hole combinations

?Fins are heat treated spring steel

?Have built-in stop collar on leading edge*

?Greater centering efficiency

?360º wall coverage for increased load bearing area

?Lower starting force

?Available with integral stops

?Turbolizer fins on only one end so they can be installed over stop collars

?High restoring force for optimum standoff

?Low moving force to minimize drag

?Allow free rotation of the pipe for maximum displacement efficiency

?Over stop collar design minimizes moving forces while reciprocating

?Meet or exceed API Specification 10D requirements

ROTATING CENTRALIZERS (MODEL STT-1SL)

Rotating centralizers were developed in response to industry requirements for centralizers that could be used with a rotating liner in highly deviated conditions. These centralizers offer the following features:

*Note: Single straight Turbolizer centralizers should never be installed over stop collars, any upset connections or over a casing collars.

?Break up of cement and drilling fluids channeling

?Deflection of mud and cement toward washed-out sections of the well bore

?Improved filter cake removal

?Self-cleaning action which prevents the Turbolizer centralizers from "balling-up”

11

WELDED CENTRALIZERS

RIGID CENTRALIZERS, LATCH-ON

These centralizers provide positive standoff and centering, and can be used in both cased or open hole applications. In cased hole situations, they can be installed below casing hanging equipment and under liner hangers to facilitate proper setting. They offer:

?Single bar or double bar — Single bar versions arerecommended for cased hole applications; double bar for open hole.

?Available in various configurations — Available in latch-on or slip-on versions and also in latch-on with integral stops.

SPRIAL-TYPE MT CENTRALIZERS

These centralizers are designed for use with multiple tubing strings (dual, triple, etc., or tubingless completions) run in one hole. The centralizers may be installed over close tolerance stop collars.

RIGID T-BAR CENTRALIZERS

These centralizers are custom built to suit severe service applications such as in subsea conditions and in large bore deviated holes where extreme axial and radial loads may be encountered. Either a T-bar or flat bar may be used to provide a large bearing surface to virtually eliminate well bore gouging. Options may include:

?Extra heavy-duty end collars

?Double rows of set screws

?Flat bar or T-bar staves

?Bronze cladding on stave ends to protect wellhead equipment

THERMAL STABILIZERS (NOT SHOWN)

Thermal stabilizers are used to insulate steam injection lines from the casing. The rigid stabilizers, with replaceable non-asbestos-compound insulation pads affixed to the bows, greatly reduce heat loss.

WELDED CENTRALIZERS

12

GRAVEL PACK CENTRALIZERS

These centralizers are designed to give a minimal amount of drag resistance when passing through the previous casing or wellhead and then spring out to fit underreamed sections and washouts.

?Useful in sections where gravel packing is being implemented

?Used for oversized holes

?Available with special clearance collars designed to go through restrictions

DEPTH ORIENTATION MARKERS (DOM)™

Weatherford Depth Orientation Markers are patented* devices which exert a focused magnetic field inside the casing so that they will affect the casing collar locator tool and provide a downhole reference point.

?Used on flush joint pipe where connections are hard to detect

?Used with non-magnetic tubulars in corrosive service

?Provide a permanent benchmark on wells for future production

?Made to match specific casing weights

?Offered in standard and close tolerance versions

?Will sometimes save a gamma ray run

MICRO-ANNULUS SEALS (CEMENT SEAL UNITS)

Weatherford micro-annulus seals are used to block off possible gas or fluid migration along the casing-cement interface. This product offers the following features:

?Reduce interzonal communications

?Prevent gas pressure on the annulus

?Deter leakage of stimulation media up the annulus

?Minimize gas storage well leakage

?Decrease loss of injection media in injection wells

?Standard model is rated to 275°F (135°C)

?High temperature model rated to 400°F (204°C)

WELDED CENTRALIZERS

WELDED CENTRALIZER SPECIFICATIONS

Notes: *1.Close Tolerance — Integral Stop-Collar

*2.Where two bow spring sizes are indicated, the lower should be used for smaller hole sizes or with light weight casing and 2 centralizers per joint installations.

*3.Type 12 and 16 bow springs are identical, 12 is for notched-in, 16 for lap-welded Close Tolerance Centralizer

BOW SPRING SELECTION GUIDE — WELDED CENTRALIZERS

13

2-3/8" 2-7/8" 3-1/2" 4-1/2" 5" 5-1/2" 6-5/8" 7" 7-5/8" 8-5/8" 9-5/8" 10-3/4" 11-3/4" 13-3/8" 16" 18-5/8" 20"

4-1/2" - 4-3/4" 30 *16 *12 -- -- -- -- -- -- -- -- -- -- -- -- -- --

5-3/4" - 6" 36 30 25 *12/16 *12 -- -- -- -- -- -- -- -- -- -- -- --

6-1/8" - 6-3/8" 46 30/36 30 *16 *12/16 -- -- -- -- -- -- -- -- -- -- -- --

6-1/2" - 6-3/4" 46 46 36 25 *16 *12 -- -- -- -- -- -- -- -- -- -- --

7-3/8" - 7-7/8" 57 46 46 36 30/36 25 *12 -- -- -- -- -- -- -- -- -- --

8-3/8" - 8-5/8" 57 57 46 36/46 36 30/36 *16/25 *16 *12 -- -- -- -- -- -- -- --

8-3/4" - 9" 85 57 57 46 46 36 25 25 *12 -- -- -- -- -- -- -- --

9-1/2" - 10" 85 85 85 57 46/57 46 36 36 25/30 -- -- -- -- -- -- -- --

10-5/8" - 11" -- 85 85 57/85 57 57 46 46 36 25/30 *12/16 -- -- -- -- -- --

12" - 12-1/4" -- -- 85 85 85 85 57 57 57 46 36 25 -- -- -- -- --

14" - 15-1/2" -- -- -- -- 85 85 85 85 85 57/85 46/57 46 36/46 -- -- -- --

17" - 18-5/8" -- -- -- -- -- -- -- -- -- 85 85 57 57 46 25/36 -- --

19-1/2" - 20-1/2" -- -- -- -- -- -- -- -- -- -- -- -- -- -- 57 -- --

22" - 23" -- -- -- -- -- -- -- -- -- -- -- -- -- -- 85 46/57 46

24" -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 57 46/57

26" -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 85 57/85

Hole Size (in)Casing Size (in inches)

Max. Bow

O.D. (in)

Min.

Comp.

O.D. (in.)

Max. Bow

O.D. (in)

Min.

Comp.

O.D. (in.)

Max. Bow

O.D. (in)

Min.

Comp.

O.D. (in.)

Max. Bow

O.D. (in)

Min.

Comp.

O.D. (in.)

Max. Bow

O.D. (in)

Min.

Comp.

O.D. (in.)

Max. Bow

O.D. (in)

Min.

Comp.

O.D. (in.)

Max. Bow

O.D. (in)

Min.

Comp.

O.D. (in.)

Max. Bow

O.D. (in)

Min.

Comp.

O.D. (in.)

4-1/2" 6.000 5.500 6.250 5.500 7.250 5.500 7.550 5.500 8.500 5.500 9.250 5.500 11.500 5.500 14.500 5.500

5" 6.500 6.000 6.750 6.000 7.875 6.000 8.250 6.000 8.750 6.000 9.750 6.000 12.000 6.000 15.000 6.000

5-1/2" 7.000 6.500 7.250 6.500 8.375 6.500 8.750 6.500 9.125 6.500 10.250 6.500 12.500 6.500 15.500 6.500

6-5/8" 8.125 7.625 8.375 7.625 9.500 7.625 9.875 7.625 10.375 7.625 11.375 7.625 13.625 7.625 16.625 7.625

7" 8.500 8.000 8.750 8.000 9.875 8.000 10.250 8.000 10.750 8.000 11.750 8.000 14.000 8.000 17.000 8.000

7-5/8" 9.125 8.625 9.375 8.625 10.500 8.625 11.000 8.625 11.500 8.625 12.375 8.625 14.625 8.625 17.625 8.625

8-5/8" 10.250 9.625 10.500 9.625 11.500 9.625 12.000 9.625 12.500 9.625 13.875 9.625 15.625 9.625 18.625 9.625

9-5/8" 11.250 10.750 11.500 10.750 12.500 10.750 13.000 10.750 13.500 10.750 14.875 10.750 16.625 10.750 19.625 10.750

10-3/4" 12.375 11.875 12.625 11.875 13.625 11.875 14.125 11.875 14.625 11.875 15.875 11.875 17.750 11.875 20.875 11.875

11-3/4" 13.375 12.875 13.625 12.875 14.625 12.875 15.125 12.875 15.625 12.875 16.875 12.875 18.750 12.875 21.875 12.875

13-3/8" 15.000 14.500 15.250 14.500 16.250 14.500 16.750 14.500 17.250 14.500 18.750 14.500 20.375 14.500 23.500 14.500

16" 17.625 17.125 17.875 17.125 18.875 17.125 19.375 17.125 19.875 17.125 21.375 17.125 23.000 17.125 26.125 17.125

18-5/8" 20.250 19.750 20.500 19.750 21.500 19.750 22.000 19.750 22.500 19.750 24.000 19.750 25.625 19.750 28.750 19.750

20" 21.625 21.125 21.875 21.125 22.875 21.125 23.375 21.125 23.875 21.125 25.375 21.125 27.000 21.125 30.125 21.125

85 Bow30 Bow 36 Bow 46 Bow 57 Bow

Casing

Size (in.)

12 Bow 16 Bow 25 Bow

LoDRAG™ CENTRALIZER

The LoDRAG centralizer is also a mechanical friction-reduction system that performs independently of drilling or completion mud film strength or lubricity. The small contact area of the rollers with the casing or borehole wall functions exceptionally well in underpressured conditions, where risk of differential sticking is high.

LoDRAG tools have been used primarily to run casing and sand-control screens into unconsolidated sandstone reservoirs. Using LoDRAG tools in these reservoirs can reduce axial drag by up to 60 percent. The LoDRAG tool can reduce axial friction in cased holes by similar percentages.

ROLLER CENTRALIZERS

?Rollers help to avoid plowing that can create major drag problems

?Precision machined inside diameter provides excellent rotational performance in mud

?Small roller contact area reduces differential sticking

?Rollers provide exceptional wear resistance

?Torque-reducing performance improves the cement sheath

?The roller/axle relationship ensures that axle shear stresses remain within elastic limits

?High quality construction materials improve high-pressure / high-temperature capabilities

LoTORQ™ CENTRALIZERS

The majority of LoTORQ tools have been used in extended-reach wells to run and rotate long, heavy-wall liners where rotation provides an optimum cement sheath.

Weatherford developed a mechanical friction (torque and drag) reduction system that performs independently from drilling/completion fluids. Analysis has shown that the small contact area of the rollers function exceptionally well in under-pressured conditions where the risk of differential sticking is high. The LoTORQ centralizers offers operators the same benefits as the LoDRAG centralizer but also serves well when long and/or heavy cemented liners are being rotated.

The features of the LoDRAG centralizer include:

LoDRAG™

LoTORQ™

The LoDRAG tools achieve optimum performance when:

14

?Casing, liner, and screens are being run into horizontal and extended-reach wells

?Centralizer wear may compromise the cement job

?Where HSE requirements ban the use of oil-based and pseudo-oilbased mud

?Underpressured formations may cause differential sticking

FLOW ENHANCEMENT TOOLS

RIGID CENTRALIZERS

Weatherford's broad offering of flow enhancement tools perform well in highly deviated and horizontal wells. They are designed in many sizes, materials and configurations to meet customer requirements, even under severe conditions.

The rigid centralizers are generally constructed in one piece to add greater strength and are held in place by high load stop collars or set screws. The tools are designed to improve cement flow while promoting maximum standoff from the bore hole.

Now Available in a Heavy Duty Version

SPIRAL RIGID CENTRALIZERS

SHORT SPIRAL RIGID CENTRALIZERS

®SPIRAGLIDER CENTRALIZERS

15

?Designed specifically for highly deviated and horizontal wells

?Ideal for use with liner hangers

?Steel construction provides superior toughness over other materials and alloys

?Fin design provides low coefficient of friction to reduce drag forces while running pipe

?Fins create vortex flow to optimize mud displacement and minimize pressure drop across the centralizer

?SPIRAGLIDER construction gives maximum standoff

?Fin design resists high sideloads

?Spiral blades yield to allow passage through unexpected undergauge open hole

?Blades overlap the entire 360º open hole circumference

?Reduced flow area between the spiral provides a vortex motion for increased fluid velocity

?Extra length gives maximum centralization

?Spiral design provides optimum flow area

?Made of high strength, corrosion resistant cast aluminum

?Used with corrosion-resistant alloys (CRA) to negate ionic transfer

?Spiral blades increase annular turbulence

?Blades are set at an average of 45º for maximum fluid swirl

?Blades and collar made of abrasion-resistant mild steel

?Continuous welds secure blades to collars

?Available with or without set screws

J5H STOP COLLARS

The J5H Stop Collar has a cross-bolt design that makes installation quick and easy. This economical collar can be used where annular tolerances are not critical.

Model J5H Stop Collar(60500

Model J10H Stop Collar(60200)

Model J10S Stop Collar(60300)

STOP COLLARS

STOP COLLARS

16

Model JSH Stop Collar(60900)

Weatherford stop collars limit the movement of mechanical cementing products on the pipe and are manufactured to withstand high axial forces. Four standard designs are available.

JSH STOP COLLARS

This hinged stop collar has an internal groove into which a spiral locking pin is driven, firmly wedging the collar into position around the casing. The JSH Stop Collar is used on both upset and non-upset casing and provides maximum annular clearance.

J10H STOP COLLARS

This stop collar is for use on casing up to 30 inches in diameter. A single row of set screws offers good gripping force and cost effectiveness.

J10S STOP COLLARS

Superb solid collar set-screw device gives excellent gripping force, and used where high axial loads are expected

in in mm in mm in mm in mm

2-3/8" 3-3/8" 86

2-7/8" 3-7/8" 98

3-1/2" 4-3/4" 121 4-1/2" 114

4-1/2" 5-5/8" 143 5-3/4" 146 5-5/8" 143

5" 6-1/2" 156 6-1/4" 159 6-1/8" 156

5-1/5" 6-5/8" 168 6-3/4" 171 6-5/8" 168

6-5/8" 7-3/4" 197 7-7/8" 200 7-3/4" 197

7" 8-1/4" 209 8-1/4" 210 8-1/4" 209

7-5/8" 8-7/8" 225 8-7/8" 225 8-7/8" 225

8-5/8" 9-7/8" 251 9-7/8" 251 9-7/8" 251

9-5/8" 10-7/8" 276 10-7/8" 276 10-7/8" 276

10-3/4" 12" 305 12" 305 12" 305

11-3/4" 13" 330 13" 330 13" 330

13-3/8" 14-5/8" 371 14-5/8" 371 14-5/8" 371

16" 17-1/2" 445 17-1/2" 445

18-5/8" 20-1/8" 511

20" 21-1/2" 546 21-1/2" 546

24" 25-1/5" 648

26" 27-5/8" 701

30" 31-7/8" 810

J10H / J10S

Collar Type / Maximum O.D.

*Other sizes available

SizeJSH J5H J4H

ROTATING WELLBORE WIPERS (MODEL 54850)

Rotating wellbore wipers can be used when well conditions do not permit reciprocation of the casing string, but do permit rotation. The 60-inch long strips are clamped tightly to the casing at intervals along the length of the wiper.

Note: Stop collars must be used with rotating wellbore wipers.

Reciprocating Wellbore Wiper

Wi l d ca t ( 5 1 0 0 7 )

WILDCAT™ SCRATCHER

Weatherford’s Wildcat scratchers remove excessive wall cake and improve the cement bond between the casing and porous formations while reinforcing the cement column. Their hinged design makes them easy to install.

For running in the hole, a series of scratchers is mounted on the casing string. The inclined external bristles abrade the wellbore during running and reciprocation. The scratchers feature large fluid-bypass slots and coiled bristles for bending durability.

WELLBORE WIPERS

RECIPROCATING WELLBORE WIPERS

These wipers remove excess wall cake to improve cement-to-formation bonding by producing a wiping action during running and reciprocation. A continuous, interlocking and overlapping loop of tempered-steel wire cable is laced into the hinged collars. A bolt holds the wipers in position and eliminates the need for stop collars. A hinged version is also available.

SPECIALTY TOOLS

17

in. mm in. mm

5360041 4-1/2" 11-1/8" 283 5-5/8" 143

5360051 5-1/2" 12-1/8" 308 6-5/8" 168

5360070 7" 13-5/8" 346 8-1/8" 206

5360075 7-5/8" 14-1/4" 362 8-3/4" 222

5360085 8-5/8" 15-1/4" 387 10-3/4" 248

5360095 9-5/8" 16-1/4" 413 9-3/4" 273

5360010 10-3/4" 17-3/8" 441 11-7/8" 302

5360013 13-3/8" 20" 508 14-1/2" 368

Other sizes upon request

Product

Number

Casing

Size

Loop O.D. Compressed O.D.

SPECIALTY TOOLS

PLUG-BACK STINGERS7Weatherford offers for rent or sale full length joints of 6.5 lb/ft. 2 / " 8

EUE 8rd N-80 tubing fully dressed with appropriate centralizers and cable scratchers. This configuration is effective with rotation and/or reciprocation, depending on hole conditions and rig capabilities. The centralizing and abrading action that the "Plug-Back Stingers" provide greatly improves the mud displacement efficiency of the cement slurry. The small diameter stinger minimizes the possibility of mud contamination in the slurry as it is withdrawn from the plugged interval and provides a "weak" point in the drill string should problems cause the pipe to be cemented in.

7Weatherford has been renting 2 / " tubing dressed to set cement 8

for over 20 years on the Gulf Coast. This service is now available from your local Weatherford representative. Tubing will come pre-dressed with hinged rotating centralizers and scratchers. The entire string usually consisting of 10, 20, or 30 joints is racked and safely stored in baskets. Additional components that are available include the drill pipe wiper darts, up-jetted diverter sub, and handling tools. Handling tools can include a TS100 Spider, base plate and elevators. Crossovers and extensions are available as needed.

“Plug-Back Stingers" provide greatly improves the mud displacement efficiency of the cement slurry.

CEMENT BASKETS (SOLID OR HINGED)

Weatherford cement baskets protect weak formations from excessive hydrostatic pressure exerted by the weight of the cementing column. They are normally installed on the casing string above the weak formations, but they are also used in stage-cementing or in cementing the annulus from the surface. Each basket’s overlapping metal fins provide maximum flexibility and fluid passage while maintaining optimum support characteristics.

Weatherford’s hinged baskets can be installed on upset pipe and can be disassembled for shipping and space economy. Special sizes upon request.

Cement baskets should be installed over stop collars to facilitate pipe reciprocation.

STANDARD CEMENT BASKET SPECIFICATIONS

18

CSG./

TBG. Size

Latch-on

Type

No. of

Bows

Slip-on

Type

No. of

Bows

Total

Length

Basket

O.D.

Min. Hole

Size

3-1/2" -- -- 1835731 10 24-1/2" 11-1/2" 5"

4-1/2" -- -- 1835741 10 24-1/2" 12-1/2" 6"

5-1/2" 1825751 12 1835751 12 24-1/2" 13-1/2" 7-1/4"

7" 1825770 14 1835770 14 24-1/2" 15" 8-3/4"

7-5/8" 1825775 14 1835775 15 24-1/2" 15-5/8" 9-1/2"

8-5/8" 1825785 16 1835785 16 24-1/2" 16-5/8" 10-5/8"

9-5/8" 1825795 18 1835795 18 24-1/2" 17-5/8" 11-5/8"

10-3/4" 1825710 18 1835710 19 24-1/2" 18-3/4" 12-3/4"

11-3/4" 1825711 20 1835711 21 24-1/2" 19-3/4" 13-3/4"

13-3/8" 1825713 24 1835713 24 24-1/2" 21-3/8" 15-1/2"

16" 1825716 28 1835716 28 24-1/2" 24" 18"

18-5/8" 1825718 34 1835718 34 24-1/2" 26-5/8" 20-5/8"

20" 1825720 34 1835720 34 24-1/2" 28" 22"

Case I:Over stop collars

Case II:Betweenstop collars

Case III:Between couplingsand stop collars

Case IV:Over couplings

Recommended Installation Patterns

CASE I

CASE II

CASE III

CASE IV

Installation of centralizers over casing coupling reduces annular flow area, concentrates lateral loads at the cou-pling, and requires extra rig time. Weatherford does not recommend this pattern for close-tolerance conditions where STA0 bows would be used.

Choosing proper installation pattern for mechanical cementing products is essential to achieving desired results.

For example, centralizers should be installed between stop collars in close-tolerance situations to avoid drag caused by increased starting forces. So contact your Weatherford representative for assistance in planning your cementation program. Weatherford will ensure that the products and the installation pattern will meet your operating requirements. This investment will pay dividends over the life of the well.

For optimal centering, centralizers are installed over stop collars. Installation on racks eliminates lost time. This pattern is not recommended in close tolerance

For optimum centering in close-tolerance pattern, centraliz-ers are positioned between stop-collars. STA0 or STA1 bows are recommended. This pattern can be installed on racks. Close tolerance welded centralizers, with integral stop collars, are available alternatives.

In this alternate close-tolerance pattern, centralizers are installed between a stop collar and the casing coupling. This pattern allows limited centralizer travel and uses only one stop collar per centralizer. Installation should not be performed on racks.

© 2002-2009. Weatherford. All rights reserved. 71.03

Weatherford International Ltd.515 Post Oak Blvd., Suite 600Houston, Texas 77027 USATel: 713-693-4000weatherford.com

Weatherford products and services are subject to the Company’s standard terms and conditions, available on request or at weatherford.com. For more information contact an authorized Weatherford representative. Unless noted otherwise, trademarks and service marks herein are the property of Weatherford. Specifications are subject to change without notice. Weatherford sells its products and services in accordance with the terms and conditions set forth in the applicable contract between Weatherford and the client.