Clock Spring Brochure

CCLLOOCCKK SSPPRRIINNGG®® Composite Repair System

for Riser Applications The Fast, Economical Solution for Pipeline Repair

No heavy or specialized installation / lifting equipment required No skilled labour required No hot work & welding No production loss Installation can be as quick as 30 minutes Complete cure within two hours Future corrosion growth is completely prevented Completely environmentally friendly and benign, when installed

Clock Spring Pipe and Pipeline Repairs

Wescott Coatings& Training Services










C CLOCK SPRING®

Table of Contents

Introduction page 3 Burst Test page 11 Installation Procedure page 14 Edge Effect page 19 Weld Repair page 22 Dent Repair page 26 Bend Repair page 32 Marker Method page 35 Field Inspection page 38 Riser Repair page 43 Snap Wrap page 47 Pipe Support page 52 Leak Stop page 56 Water Activated page 66 Wet Wrap vs. Clock Spring® Composite Repair page 73 Pressure Reduction page 77 NACE #3 page 78 Condensing Pipe page 79 Unique Repairs page 80 Approvals page 84 Reference List page 99 Certification page 103 Frequently Asked Questions page 105 Disposal page 112

Simply the smartest pipeline repair decision you can make!

Clock Spring Company L.P.● 14107 Interdrive West ● Houston, Texas, 77032

Telephone 281.590.8491 ● 800.471.0060 ● Fax 281.590.9528 Clock Spring ● UK 2 Woodlands, Warboys, Huntingdon, Cambs, PE17 2UR, England

Telephone 011 44 1487 824 449 ●Fax 011 44 1487 824 451 www.clockspring.com

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Contents


T | 01914975550E | [email protected] | www.wescottcoatings.com

WescottCoatings&TrainingServicesLTDUnit9B,TynePointIndustrialEstateJarrow,TyneandWear,NE323UP

Introduction 03

Burst Test 11

Installation Procedure 14

Edge Effect 19

Weld Repair 22

Dent Repair 26

Bend Repair 32

Marker Method 35

Field Inspection 38

Riser Repair 43

Snap Wrap 47

Pipe Support 52

Leak Stop 56

Composite Repair System for Riser Applications 60

Snap Wrap Offshore Extended Version/Structural Repair 61

Contour & Swap Wrap Combination Offshore Riser Repair 62

Clock Spring Offshore Riser 63

C CLOCK SPRING®

Table of Contents

Introduction page 3 Burst Test page 11 Installation Procedure page 14 Edge Effect page 19 Weld Repair page 22 Dent Repair page 26 Bend Repair page 32 Marker Method page 35 Field Inspection page 38 Riser Repair page 43 Snap Wrap page 47 Pipe Support page 52 Leak Stop page 56 Water Activated page 66 Wet Wrap vs. Clock Spring® Composite Repair page 73 Pressure Reduction page 77 NACE #3 page 78 Condensing Pipe page 79 Unique Repairs page 80 Approvals page 84 Reference List page 99 Certification page 103 Frequently Asked Questions page 105 Disposal page 112





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Introduction There are over 400,000 miles of high-pressure gas gathering and transmission pipelines and 800,000 miles of local distribution lines in the U.S., many of which were installed in the 1950-1980 period. Monitoring and preventive maintenance of this vast network to provide safe and reliable energy services comprises a significant part of the operating and maintenance costs of the pipeline industry.

Clock Spring® Background

In 1987, The Gas Research Institute formed a team to evaluate alternative repair techniques to complement cutout and replace and steel sleeves. This team consisted of the following members:

Gas Research Institute ITW Plexus Battelle North Western University Stress Engineering Kiefner and Associates Southwest Research Institute Clock Spring Company NCF Industries

The teams’ mandate was to determine the feasibility of using composites as a repair alternative for high-pressure pipelines. This 10-year research and testing program consisted of the following DESIGN CRITERIA:

• Non-intrusive • Applicable to in-service pipelines

• Permanent repair • Cost effective

• Fully predictable and verifiable by modeling and definitive equations • Eliminate all installation variables

• Effective in all locations and environments • Effective for all pipe grades and sizes

• Meet or exceed current code requirements • Eliminate field design and field engineering

• Conservatively restore the pipe to its original strength • Rigorously tested and subjected to peer review

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Introduction

Clock Spring Background

Introduction There are over 400,000 miles of high-pressure gas gathering and transmission pipelines and 800,000 miles of local distribution lines in the U.S., many of which were installed in the 1950-1980 period. Monitoring and preventive maintenance of this vast network to provide safe and reliable energy services comprises a significant part of the operating and maintenance costs of the pipeline industry.

Clock Spring® Background

In 1987, The Gas Research Institute formed a team to evaluate alternative repair techniques to complement cutout and replace and steel sleeves. This team consisted of the following members:

Gas Research Institute ITW Plexus Battelle North Western University Stress Engineering Kiefner and Associates Southwest Research Institute Clock Spring Company NCF Industries

The teams’ mandate was to determine the feasibility of using composites as a repair alternative for high-pressure pipelines. This 10-year research and testing program consisted of the following DESIGN CRITERIA:

• Non-intrusive • Applicable to in-service pipelines

• Permanent repair • Cost effective

• Fully predictable and verifiable by modeling and definitive equations • Eliminate all installation variables

• Effective in all locations and environments • Effective for all pipe grades and sizes

• Meet or exceed current code requirements • Eliminate field design and field engineering

• Conservatively restore the pipe to its original strength • Rigorously tested and subjected to peer review

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Major Benefits of Clock Spring®

• No shielding of Cathodic Protection systems • Better for the pipeline as all hoop stress is removed from the defect area

• Completely environmentally friendly and benign, when installed

• Scientifically proven as a 50 year permanent repair

• No heavy or specialized installation equipment needed

• No skilled labor required

• No hot work & welding required

• No pipeline operation interruption

• Installation in 15 minutes

• Complete cure within 2 hours, dig area can then be backfilled

• Future corrosion growth completely prevented

• Used in all environments…Artic, Desert, Offshore, Above Ground,

Underground, Subsea…

• Future intelligent pig surveys can “see” beneath the installed repair

• Experience with total success in over 65,000 installations in 63 countries worldwide

The result of this exhaustive development effort is the Clock Spring® repair system.


Clock Spring Company L.P.● 14107 Interdrive West ● Houston, Texas, 77032 Telephone 281.590.8491 ● 800.471.0060 ● Fax 281.590.9528

Clock Spring ● UK 2 Woodlands, Warboys, Huntingdon, Cambs, PE17 2UR, England Telephone 011 44 1487 824 449 ●Fax 011 44 1487 824 451

www.clockspring.com

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Major Benefits of Clock Spring

Each Accessory Kit Contains the Following:

2 - Alignment Block 2 - 3” Putty Knife

1 - Breakaway Blade Knife 1 - Jiffy Mixer

1 - Squiggle Adhesive Scrapper 1 - 1” Filament Tape 1 - Plastic Trash Bag

1 - Starter Pad 1 - Adhesive Stir Stick

1 - Roller Handle 1 - Roller Sleeve 1 - Adhesive Tray

1 - Dual Lock Tight Pad (Velcro) 2 - 2” Paint Brush

1 - Installation Guide

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Each Accessory Kit Contains the Following:

2 - Alignment Block 2 - 3” Putty Knife

1 - Breakaway Blade Knife 1 - Jiffy Mixer

1 - Squiggle Adhesive Scrapper 1 - 1” Filament Tape 1 - Plastic Trash Bag

1 - Starter Pad 1 - Adhesive Stir Stick

1 - Roller Handle 1 - Roller Sleeve 1 - Adhesive Tray

1 - Dual Lock Tight Pad (Velcro) 2 - 2” Paint Brush

1 - Installation Guide

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Clock Spring® Features

Highly effective, ingeniously simple… the Clock Spring® pipeline reinforcement system redefines the economics of pipeline repair. Installing Clock Spring® is simple. Each kit contains everything needed to make permanent pipeline repairs. No machinery or highly skilled personnel are required. A two-man crew can be trained in just a few hours to install the Clock Spring® system. It's safer. Because Clock Spring® is a composite, using an extremely durable, proprietary adhesive to bond to the pipe's surface, no welding or hot work is required. As a result, the dangers of burn-through, metal embrittlement, and cracking in the weld zone are completely eliminated. In nearly all cases, installation can be completed while the line is in operation. Plus, since there's no need to cut out or remove pipe, there are no environmental risks or waste disposal problems. It’s economical. Clock Spring® is much less expensive to install and fits more closely to the carrier pipe than conventional steel sleeves. Compared to cutouts or actual pipe replacement, Clock Spring® is usually substantially cheaper. Because it installs so quickly, time, equipment and labor costs are vastly reduced, and throughput is never interrupted.

1. A patented, high-strength, unidirectional composite structure. 2. A patented, fast-curing, high performance two-part adhesive system. 3. An extremely high compressive strength, proprietary load transferring component. Once installed, the three elements bond together to form an extraordinarily strong, durable repair.

The Clock Spring® System

It's faster. Installing Clock Spring® involves a quick, three-step process: treating and

filling the damaged or corroded section, wrapping the Clock Spring® sleeve, and applying a traditional coating (tape, heat-shrink or painted). Typical repairs take less than 25 minutes to actually install. The innovative adhesive cures amazingly fast. In less than two hours, start to finish, the repair is complete, leaving the repaired area even stronger than when the pipe was new.

It's proven. Literally thousands of hours of research have gone into the Clock Spring® system. It has been exhaustively tested and proven reliable and extremely durable by an array of respected independent research organizations under the management of the Gas Research Institute.

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Clock Spring Features

APPROVED 50 YEAR PERMANENT REPAIR FOR USE ON UP TO 80% METAL LOSS DEFECTS.

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ONCE CURED, CLOCK SPRING® IS SUTIABLE FOR USE IN ALL ENVIRONMENTS

ON 4” – 56” DIAMETER PIPELINES

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56” HIGH PRESSURE GAS PIPELINE REPAIRS

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56” High Pressure Gas Pipeline Repairs

CLOCK SPRING® REPAIR VS. CONVENTIONAL REPAIRS

MMiinnoorr Major Major Timescale CCoommppeettiittiivvee High High Price

NNoonnee Major Major Heavy Equipment NNoonnee Yes None Annular corrosion NNoonnee Yes Yes Radiography NNoonnee Yes Yes Fillet welds NNoonnee Substantial Substantial Welding SSeemmii High High Labor skill level

SSmmaallll Large Large Labor force required

NNoonnee Minor Major Production Loss

CClloocckk sspprriinngg Welded steel sleeve

Cut out & Replace

Activity

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10

Clock Spring Repair vs. Conventional Repairs

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BURST TEST ON UNREPAIRED SPOOL

Defect Length = 7.87in, Defect Width = 2.95in, Depth = 80% Wall Loss

Defect Burst at 70 Bar

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Burst Test on Unrepaired Spool

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BURST TEST WITH CLOCK SPRING REPAIR

Clock Spring Repair Made on Same Size Defect

Pipe Burst at 200 Bar! Clock Spring® repair remains unaltered!

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Burst Test with Clock Spring Repair

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BURST TEST CROSS-SECTION

Cross-section Photo: Under the Clock Spring®, the pipe kept its original circular shape as the Clock Spring® shares the stress of the pipe wall.

Detail: There is NO deformation of the defect, because the stress is completely transferred to the Clock Spring®.

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Burst Test Cross-Section

INSTALLATION PROCEDURE

CLOCK SPRING® IS SUPPLIED IN A COMPLETE KIT FORM FOR EACH PIPE DIAMETER SIZE AND INCLUDES: THE COIL, FILLER, ADHESIVE AND ALL APPLICATION ITEMS.

PHOTORAPHS SHOW MIXING AND PREPARING THE TWO COMPONENT FILLER AND ADHESIVE.

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Installation Procedure

DEFECT AREA IS CLEANED AND SIZED. IF POSSIBLE, AREA SHOULD BE SAND BLASTED TO A NACE 3 FINISH. IF THIS IS

NOT POSSIBLE, AREA SHOULD BE GROUND CLEAN TO REMOVE ALL LOOSE DEBRIS.

THERE IS NO NEED TO DECREASE THE PIPELINE OPERATING PRESSURE FOR DEFECTS BELOW 50% METAL LOSS.

THE DOUBLE SIDED ADHESIVE STARTER PAD IS APPLIED TO THE PIPE SURFACE.

FILLER IS APPLIED TO THE DEFECT AREA, AS WELL AS ALL RAISED AREAS SUCH AS SEAM OR SPIRAL WELD.

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LEADING EDGE OF THE COIL IS PLACED ON THE STARTER PAD. THE COIL IS THEN WOUND AROUND THE PIPE WHILE

ADHESIVE IS APPLIED TO EACH LAYER.

AS STANDARD, EACH COIL IS A COMPLETE EIGHT (8) WRAPS AROUND THE PIPE.

INSTALLATION CAN BE COMPLETED WITHIN 15 – 25 MINUTES

DEPENDING ON THE PIPE DIAMETER.

EACH COIL HAS A “MEMORY MATRIX”, WHICH ONCE THE COIL IS INSTALLED, TIGHTENS THE COIL TO THE PIPE DIAMETER. ADDITIONAL TIGHTENING OF THE COIL IS

ACHIEVED USING THE CINCH BAR WHILE FILAMENT TAPE IS APPLIED TO HOLD THE COIL IN PLACE WHILE CURING.

COMPLETE CURE SHOULD BE ACHIEVED IN TWO (2) HOURS.

THE COIL CAN THEN BE COATED AND BACKFILLED.

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FOR LARGE PIPE DIAMETERS, 24” AND GREATER, IT IS RECOMMENDED A “SPOOL FEEDER” IS USED.

THIS IS ATTACHED TO THE PIPE AND SUPPORTS THE WEIGHT OF THE COIL. THE COIL IS THEN WOUND AROUND

THE PIPE AND ADHESIVE IS APPLIED TO EACH LAYER.

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THESE PHOTOS DEPICT FINSHED INSTALLATIONS MADE USING THE SPOOL FEEDER SYSTEM. THE SPOOL FEEDER

SHOULD ALSO BE USED WHEN THERE IS MINIMAL CLEARANCE AVAILABLE AROUND THE PIPE OD.

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CLOCK SPRING® Application Note Reinforcement Edge Effect There are times when a single Clock Spring® is not wide enough to complete a repair. In this case, two or more units are used side-by-side (Figure 1), to cover the defect area and provide the 2-inch (50 mm) overlap specified for the repair. These units are spaced as close as possible with a maximum gap of 0.25 inches (6 mm). This gap is still reinforced because of a phenomenon called 'edge effect'.

Figure 1. Multiple Clock Spring® Units

Similarly, defects in bends can be reinforced with Clock Spring® but the repair is complicated by the radius of the elbow or fitting. In this case, the composite must be installed as narrow bands instead of the nominal 12-inch (305 mm) width to accommodate the shape of the elbow. This results in continuous reinforcement of the intrados but a separation of the bands on the extrados as can be seen in Figure 2a and 2b. The specification for a bend repair requires that this separation on the extrados not exceed 0.50-inches (13 mm). The width of the composite bands and the gap at the extrados are controlled by the geometry of the fitting. Bend repairs should be reviewed by a Clock Spring® representative to ensure adequate design.

Figures 2a, 2b. Reinforcement of Bends

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The reinforcement provided by Clock Spring® does not stop instantly at the edge of the unit but rather decrease linearly over a short distance beyond the Clock Spring®. The rate of decrease of reinforcement with distance is complex and must be calculated using finite element analysis (FEA) and verified by full scale testing. This work was done for Clock Spring® repairs and is reported in GRI – 93/0346 "Clock Spring® Reinforcement of Elbow Fittings". The findings in this report are summarized in Figure 3.

Reinforcement Reduction

020406080

100120

0 0.25 0.5 0.75

Distance (inches)

Rei

nfor

cem

ent (

%) Test data

(absolute)Test datanormalizedFEA data(absolute)FEA datanormalizedRule of Thumb

Figure 3 shows both FEA and test data for the reduction in reinforcement past the edge of the Clock Spring® unit. The data is presented as absolute values and normalized to 100%. The 100% represents the reinforcement of a standard Clock Spring® unit.

Figure 3. Reduction in Reinforcement Beyond Edge of Clock Spring®

The x-axis is distance from sleeve edge. That is, 0.25 inches (6 mm) represents the middle of a 0.5-inch (13 mm) gap. The 0.5-inch (13 mm) maximum gap specified for the extrados gap of a bend repair will still be adequately reinforced. Clock Spring Company has determined that as a "rule of thumb" the rate of reinforcement decrease can be approximated by 25% per 0.25-inches (4% per mm). This curve (normalized) is also shown in Figure 3. When more than one Clock Spring® is used to reinforce defects in straight pipe the gap between the units is specified as 0.25 inches (6 mm). The edge effect ensures adequate reinforcement in the center of the gap.


Clock Spring Company L.P.● 14107 Interdrive West ● Houston, Texas, 77032 Telephone 281.590.8491 ● 800.471.0060 ● 281.590.9528

Clock Spring ● UK 2 Woodlands, Warboys, Huntington, Cambs PE17 2UR, England Telephone 011 44 1487 824 449 ●Fax 011 44 1487 824 451

www.clockspring.com

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20Wescott Coatings& Training Services



EACH CLOCK SPRING® IS 12” WIDE. 2” OF PRISTINE PIPE ARE REQUIRED FROM THE EDGE OF THE DEFECT TO

THE END OF THE COIL.

FOR LARGE AREAS OF GENERAL CORROSION, COILS CAN BE APPLIED SIDE BY SIDE.

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CLOCK SPRING® Application Note Weld Repair Clock Spring® composite repair system can be used to reinforce corrosion or other blunt defects that affect the girth weld zone. Clock Spring® provides hoop reinforcement for pipe damaged by corrosion or other blunt defects by wrapping tightly around the pipe and sharing the hoop load. The cap of a girth weld restricts the Clock Spring® contact with the pipe. Defects in the weld zone can be repaired by bridging the weld cap with an additional Clock Spring® unit. Clock Springs are installed on either side of the weld; the space between the units is filled with high compressive strength filler and a third unit installed over the filled gap.

Weld Bridge Application Note Scope: The following technique will provide structural reinforcement for external corrosion, or other blunt defects associated with the girth weld zone. The three steps to the process are:

1. Application of Clock Spring® on both sides of the weld. 2. Molding the area between the Clock Spring® units (over the weld bead)

with filler material using a single wrap mold. 3. Application of the bridging unit.

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Application Guidelines: 1. Only certified installers may apply Clock Spring®. 2. The pipeline operator must inspect the weld zone to ensure that it is free

of cracks. 3. Defect shall not exceed the following

a. 50% pipe wall loss b. 30% of the pipe circumference

4. The following additional material is required. Filler kits, single-wrap mold, parting film, tie-down straps, 100-grit sandpaper.

Installation Steps: 1. Install a Clock Spring® unit on each side of the girth weld. (See Figure 1)

Optional: Six-inch (150 mm) wide Clock Spring® may be used. 2. Remove all extruded material from the area of the girth weld. 3. Allow adhesive to cure and remove the securing filament tape nearest the

girth weld. 4. Apply filler material to the area between the Clock Spring® units (over the

weld bead). Install the parting film and the single-wrap Clock Spring mold. Tighten the mold using the tie-down straps. (See Figure 2)

5. Remove all extruded filler material. 6. Allow the filler to harden (approximately 1-1/2 hours). Cure time will be

affected by temperature. 7. Remove mold, lightly abrade filler and the exterior of the installed Clock

Springs, and wipe abraded area. 8. Apply filler material as required to all voids, center and install the “Bridging”

Clock Spring® unit over the girth weld in accordance with standard Clock Spring® repair procedures. (See Figure 3)


Clock Spring Company L.P.● 14107 Interdrive West ● Houston, Texas 77032 Telephone 281.590.8491 ● 800.471.0060 ● Fax 281.590.9528


www.clockspring.com

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DOUBLE GIRTH WELD REPAIR

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DOUBLE GIRTH WELD REPAIR

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Double Girth Weld Repair

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CLOCK SPRING®

Application Note Dent Repair The following procedure provides the generic approach to reinforcing dented pipe sections. Reinforcing dented pipe reduces cyclical loading that can lead to time dependent failure. Fatigue testing indicates that the Clock Spring® repair system extends the fatigue life for dressed mechanical defects by an order of magnitude over grinding as the sole repair. (GRI Report No. GRI-97-0413 "Evaluation of a Composite System For Repair of Mechanical Damage in Gas Transmission Lines"). The repair is limited to smooth dents caused by inadvertent pipe contact with machinery or objects in the ditch or backfill. Stress concentrators in the dent must be removed in accordance with applicable codes and the dent area inspected for surface cracking. Contact the Clock Spring Company, L.P. or a designated representative for more information.

Figure 1

Figure 2

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CLOCK SPRING®

Application Note Dent Repair The following procedure provides the generic approach to reinforcing dented pipe sections. Reinforcing dented pipe reduces cyclical loading that can lead to time dependent failure. Fatigue testing indicates that the Clock Spring® repair system extends the fatigue life for dressed mechanical defects by an order of magnitude over grinding as the sole repair. (GRI Report No. GRI-97-0413 "Evaluation of a Composite System For Repair of Mechanical Damage in Gas Transmission Lines"). The repair is limited to smooth dents caused by inadvertent pipe contact with machinery or objects in the ditch or backfill. Stress concentrators in the dent must be removed in accordance with applicable codes and the dent area inspected for surface cracking. Contact the Clock Spring Company, L.P. or a designated representative for more information.

Figure 1

Figure 2

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Figure 3

Figure 4

Figure 5





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GAS PIPELINE DENT REPAIR

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Gas Pipeline Dent Repair

CLOCK SPRING® Application Note Effectiveness of dent repair using Clock Spring® Clock Spring® composite repair system can be used to reinforce dents in high-pressure pipelines. Fatigue testing indicates that Clock Spring® extends the fatigue life for dressed mechanical defects by an order of magnitude over grinding as the sole repair. (GRI Report No. GRI-97-0413 "Evaluation of a Composite System For Repair of Mechanical Damage in Gas Transmission Lines"). The repair is limited to smooth dents caused by inadvertent pipe contact with machinery or objects in the ditch or backfill. Stress concentrators in the dent must be removed in accordance with applicable codes and the dent area inspected for surface cracking.

Un-repaired--------------------● Grinding only------------------X Clock Spring® & Grinding--◊

Num

ber o

f Cyc

les

Diameter / wall thickness

Figure 1. Number of Cycles as a Function of Pipe Diameter to Wall Thickness Ratio

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Three groups of data are plotted in Figure 1,

1. PRCI/GRI data for un-repaired dents with gouges (Lower) 2. GRI data for partially repaired defects (Grinding out stress riser)(Middle) 3. GRI data for fully repaired defects (Grinding plus Clock Spring®)(Upper)

Cycles to failure are plotted against Diameter / Wall thickness ratio (D/t). Analysis yields several observations.

• At a D/t of 60, the fatigue life for partially repaired defects is approximately one order of magnitude greater than the fatigue life of un-repaired defects.

• The fatigue life of fully repaired defects is approximately two orders of magnitude greater that un-repaired defects.

• Fatigue life of un-repaired and partially repaired defects increases with increasing D/t. There is not enough data to estimate the trend line for fully repaired data so it is shown flat.

Un-repaired--------------------● Grinding only------------------X Clock Spring® & Grinding--◊

Num

ber o

f Cyc

les

Gouge Depth / Wall Thickness (%)

Figure 2. Number of Cycles as a Function of Gouge Depth

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Figure 2 provides data plotted with the gouge depth being the variable of interest. As with figure 1, the following data groups are presented,

1. PRCI/GRI data for un-repaired dents with gouges (Lower) 2. GRI data for partially repaired defects (Grinding out stress riser)(Middle) 3. GRI data for fully repaired defects (Grinding plus Clock Spring®)(Upper)

Several observations can be made,

• The fatigue life of a dent with a gouge decreases with increasing gouge depth.

• The fatigue life of partially repaired defects is greater than un-repaired defects by two orders of magnitude at the 15 % gouge depth.

• The fatigue life of fully repaired defects is greater than un-repaired defects by three orders of magnitude at the 15% gouge depth.

Clock Spring® repair system is effective in increasing the fatigue life of mechanical defects (dents). Stress concentrators or gouges must be removed prior to Clock Spring® installation




www.clockspring.com

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CLOCK SPRING® Application Note Bend Repair Clock Spring® provides hoop reinforcement for pipe damaged by corrosion or other blunt defects by wrapping tightly around the pipe and sharing the hoop load. Defects in bends require special consideration to ensure that the following design requirements are met (Figure 1a, b, c).

1. The repair area shall have the installed Clock Spring® units extend a minimum of 2 inches (51 mm) beyond both ends of the defect.

2. The gap between the Clock Spring® and the intrados of the bend shall not

exceed 0.187 inches (4.8 mm).

3. The gap between adjacent Clock Spring® units on the extrados of the bend shall not exceed 0.5 inches (12.7 mm).

4. The width of each Clock Spring® unit shall not be less than 2.5 inches

(63.5 mm). Figures 1a, b, c Bend Repairs

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The design of the bend repair requires specific information about the bend. In addition to pipe grade, diameter, wall thickness, class location, defect length, defect width and defect depth; provide: Installation Requirements: 1. ONLY Certified Installers may install Clock Springs. 2. Install Clock Spring® units in accordance with standard Clock Spring® repair

procedures. 3. Start the installation of Clock Spring® units from the middle of the defect

moving outwards. 4. In addition to applying filler material to all cavities and tented areas, ensure

that filler is applied to both the intrados and extrados area of the pipe contacting the Clock Spring® unit.




www.clockspring.com

Figure 2

(S1 and S2) Or

(C and H) Or BR.

See Figure 2.

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1.5 BEND REPAIR BEND REPAIR

CLOCK SPRING® USED AS A REINFORCEMENT SYSTEM FOR OFFSHORE OIL RISERS

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CLOCK SPRING® Application Note Clock Spring® Marker Introduction Pipelines require periodic inspection to detect imperfections in the wall of the pipe that could lead to subsequent failure of the pipeline. This inspection is done by several methods, the most common of which is running an inspection tool through the pipe. These tools are designed to inspect the steel for imperfections by use of various technologies including, but not limited to, ultrasonic and magnetic flux leakage. Magnetic flux leakage is the most common technology used for this inspection task. It is valuable for a pipeline operator to be able to detect prior repairs on subsequent inspection so that time is not spent determining the disposition of a defect detected by the inspection equipment. The older more traditional repairs are identifiable in the magnetic flux leakage inspection tool data but the Clock Spring® composite repairs are invisible to this technology. This procedure provides a means by which a magnetic flux leakage inspection tool can detect Clock Spring® composite repairs. Having the Clock Spring® identified in the tool data provides definitive information about previous repairs and serves to identify locations that may be used to verify tool performance. Detailed measurements of the defect should be acquired before installation of the Clock Spring®. This information should then be filed for future reference. On subsequent inspections, this information can confirm the performance of the inspection tool or be used to help calibrate the inspection tool for better data analysis.

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CLOCK SPRING® Application Note Clock Spring® Marker Introduction Pipelines require periodic inspection to detect imperfections in the wall of the pipe that could lead to subsequent failure of the pipeline. This inspection is done by several methods, the most common of which is running an inspection tool through the pipe. These tools are designed to inspect the steel for imperfections by use of various technologies including, but not limited to, ultrasonic and magnetic flux leakage. Magnetic flux leakage is the most common technology used for this inspection task. It is valuable for a pipeline operator to be able to detect prior repairs on subsequent inspection so that time is not spent determining the disposition of a defect detected by the inspection equipment. The older more traditional repairs are identifiable in the magnetic flux leakage inspection tool data but the Clock Spring® composite repairs are invisible to this technology. This procedure provides a means by which a magnetic flux leakage inspection tool can detect Clock Spring® composite repairs. Having the Clock Spring® identified in the tool data provides definitive information about previous repairs and serves to identify locations that may be used to verify tool performance. Detailed measurements of the defect should be acquired before installation of the Clock Spring®. This information should then be filed for future reference. On subsequent inspections, this information can confirm the performance of the inspection tool or be used to help calibrate the inspection tool for better data analysis.

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Procedure The procedure outlined is only effective for Magnetic Flux Leakage (MFL) inspection tools. Because of the varying performance of inspection tools, no guarantee is given or implied. This method has been demonstrated to be effective. Measure the external defect and record results for future reference. Install the Clock Spring® using standard installation procedures. Wrap five (5) layers of steel banding material on top of the Clock Spring® at each end. (See Figure 1.) The banding material is standard 1.25” x .031” steel strap used for material shipping. (Groves Industrial Supply #14031) Coat and back-fill. The purpose of this procedure is to place additional metal in close proximity to the pipe. Magnetic Flux Leakage (MFL) inspection tools can detect this additional metal and thus provide a Clock Spring® reference signal in the recorded data. Figure 1 shows metal banding placed on top of the Clock Spring®. While this ensures that the banding is insulated from the pipe, it does require additional material. Alternatively, the metal banding can be placed on the pipe immediately outside the Clock Spring®. In this case, three (3) wraps of banding can be used. The banding in this case should be insulated from the pipe by a thin membrane. Banding in this position will be easier for the inspection tools to detect and is most likely to generate an easily recognizable signal in the data. Figure 1.

Banding Material Clock Spring® Identifier

Adhesive

Pipe Clock Spring®

Inspection data showing Clock Springs identified by banding material.

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Procedure The procedure outlined is only effective for Magnetic Flux Leakage (MFL) inspection tools. Because of the varying performance of inspection tools, no guarantee is given or implied. This method has been demonstrated to be effective. Measure the external defect and record results for future reference. Install the Clock Spring® using standard installation procedures. Wrap five (5) layers of steel banding material on top of the Clock Spring® at each end. (See Figure 1.) The banding material is standard 1.25” x .031” steel strap used for material shipping. (Groves Industrial Supply #14031) Coat and back-fill. The purpose of this procedure is to place additional metal in close proximity to the pipe. Magnetic Flux Leakage (MFL) inspection tools can detect this additional metal and thus provide a Clock Spring® reference signal in the recorded data. Figure 1 shows metal banding placed on top of the Clock Spring®. While this ensures that the banding is insulated from the pipe, it does require additional material. Alternatively, the metal banding can be placed on the pipe immediately outside the Clock Spring®. In this case, three (3) wraps of banding can be used. The banding in this case should be insulated from the pipe by a thin membrane. Banding in this position will be easier for the inspection tools to detect and is most likely to generate an easily recognizable signal in the data. Figure 1.

Banding Material Clock Spring® Identifier

Adhesive

Pipe Clock Spring®

Inspection data showing Clock Springs identified by banding material.

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Figure 1

Figure 2 MFL Data Showing Clock Spring® Repairs

Figure 2 shows Tuboscope Magnetic Flux Leakage inspection data of two Clock Springs and a girth weld. The Clock Spring® composite repairs are identified by banding material placed on each edge of each unit. (Each Clock Spring® unit is nominally 1 foot wide.) The defects repaired with the Clock Springs are clearly shown in the data. The signals from the defect are unaffected by the Clock Spring® and can be used on subsequent inspections to calibrate the tool.




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CLOCK SPRING® Introduction Occasionally, during the course of routine maintenance, a Pipeline Company will daylight an existing Clock Spring® repair. The Company might then like to assess and confirm the condition of the Clock Spring®. Field Inspection There is very little testing that can be done, insitu, to test the Clock Spring®. Visual inspection will provide the best indication of performance. The Clock Spring® installation should be inspected to ensure that… • the coating is continuous and free of defects. • there are 8 layers of Clock Spring® material. (thickness >0.36 inches (9 mm)). • the repair is a monolithic structure. • there is no evidence of movement. • the resin is hard and the glass fibers fully contained. The adhesive can be tested to ensure that it has a minimum hardness of 40 durometer on the Shore "A" hardness scale.

Clock Spring® repairs, properly installed, will not fail because of exposure to the environment. The conservative estimate of life is a minimum of 50 years. This is fully documented in a number of technical reports. Prior Testing Clock Spring’s effectiveness as a permanent repair for high-pressure transmission pipelines is substantiated by an impressive series of tests. These tests were necessary to satisfy both Pipeline Companies and Regulators that the technique is effective. These tests are detailed in GRI Report 98/0032 "Field Validation of Composite Repair of Gas Transmission Pipelines" These tests are further summarized in GRI Report 98/0227 "Summary of Validation of Clock Spring® for Permanent Repair of Pipeline Corrosion Defects". The Field Verification Testing of over 100 Clock Spring® installations was done to confirm laboratory testing in actual field operating environments. Following is a brief summary of the key elements of the laboratory research pertinent to the field validation effort.

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Composite Short-term Strength and Physical Properties

Clock Spring® is manufactured by encapsulating tows of continuous E-glass fibers in an isophthalic polyester resin matrix. The wet fibers are then wound and cured around a cylindrical mandrel to form the characteristic Clock Spring® shape. The resulting composite laminate layers are nominally 0.065-inches thick and have a glass fiber content ranging from 60 to 70 percent by weight (45 to 55 percent by volume). The density of the cured composite laminate ranges from 0.61-to 0.69-lb/cubic inches.

Short-term and long-term tensile tests were carried out using standard ASTM composite tensile specimens cut from 12 inch wide flat plate panels of the Clock Spring® composite system. The tensile strength of these samples, under worst-case conditions of full immersion in water at 140º F, was 52 to 85 ksi. These data are from narrow 0.5-inch wide strips and represent a lower bound to the actual strength of the full 12-inch wide commercial panel. The Clock Spring® composite material exhibits linear elastic behavior up to the point of failure in tension, typically 1.5 to 2 percent strain. Typical values of the elastic modulus are 5 x 106 psi in the fiber direction and 1.4 x 106 psi in the transverse direction. The coefficient of thermal expansion was found to be 6.0 x 10-6 inch/inch/degree F in the fiber direction and 3.2 x 10-5 inch/inch/degree F in the transverse direction.

Long-term Composite Strength in Pipeline Environment The strength of polymer composites subjected to high stress in severe environments is known to decrease with time. In pipeline repair applications, Clock Spring® is not highly stressed, nor is the environment unusually severe or deleterious. Long-term static load (stress-rupture) tests were performed in the laboratory research program on saturated, 0.5-inch wide samples at elevated 140º F temperatures. These tests were to verify sufficient long-term residual strength and performance of the Clock Spring® material as a permanent repair. These tests represented a worst-case condition for the environment to which the Clock Spring® would be subjected. Figure 2 summarizes the results of the long-term testing. In these tests the gauged sections of saturated 0.5-inch wide samples were continuously immersed in de-ionized water at nominal pH ranging from 4 to 9.5, representing typical soil moisture conditions, and at temperatures of 120º F and 140º F. No fundamental change in the failure mechanism was observed in the long-term stress-rupture specimens to indicate degradation in properties. The lower bound line to the worst-case failure data indicates that 20 ksi is a conservative long term operating stress for a 50-year life.

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Figure 2. Long-term Durability and Residual Strength of Saturated Clock Spring® at 140 F.

Long-term static load tests were maintained for up to 20,000 hours (27 months). During this time, no specimen failed at less than 30 ksi. At the conclusion of the static load testing the un-failed specimens were subjected to conventional tensile testing at 140º F. The residual strength of the un-failed specimens, coupled with the test duration, indicate that no significant damage had been sustained by the samples at stresses of 18 to 35 ksi for test durations up to 20,000 hours. Long-term Clock Spring® Design Stress

The maximum operating stress for transmission pipelines in the United States ranges from 40 to 72 percent of their specified minimum yield strength (SMYS), depending upon the class location. ASME pipeline design codes require that any defect present in the pipeline due to corrosion or other factors must be able to withstand a hydrostatic test of the pipe to the equivalent of 100 percent of SMYS. Similarly the composite repair model GRIWrap™ uses the 50 year maximum stress of 20 ksi for long term Clock Spring® composite repair. GRIWrap™ requires that the repaired defect also be able to withstand a hydrostatic test of the pipe to the equivalent of 100 percent SMYS hoop stress throughout its design life.

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Adhesive Material Investigation The Clock Spring® composite is bonded to the pipe and to itself with an interlayer adhesive. A typical Clock Spring® installation consists of 8 complete wraps of the pipe to form a monolithic, 0.50-inch thick structure. The adhesive is a proprietary epoxy/methyl methacrylate known as MA440. An analysis of the stress field in the Clock Spring® adhesive by Stress Engineering Services Inc. shows that the maximum adhesive stress is at the ends of unit and will likely remain below 200 psi. The Clock Spring® adhesive strength was measured in the laboratory to range from 1100 to 1500 psi. The effects of stress and variability of soil pH were investigated. In these tests the Clock Spring® laminates were submerged in heated water baths at different pH levels and loaded under constant stress for periods of up to 10,000 hours (13 months). While the adhesive strength did diminish in these tests, it remained well above that strength required for the Clock Spring® application. Field Validation Program

Laboratory analysis showed that Clock Spring® is an effective permanent repair technique for high-pressure transmission pipelines. To fully validate this laboratory data a comprehensive Field Validation Program was established. Over 100 Clock Springs were installed at various locations across the United States in conjunction with this investigation. The locations and installation conditions varied widely, representing the broad range of conditions expected for application of the composite wrap. Soil conditions at the sites ranged from red clay to dry sand. Installation temperatures ranged from 40º F to 95º F. This program focused on three areas:

• Comprehensive monitoring of Clock Spring® on an operating pipeline,

including inspection and laboratory testing after 2 to 4 years of exposure, electronic monitoring of strains over 4 years, and testing of adhesive panels buried with the Clock Springs.

• Installation of Clock Springs on 10 operating pipelines and subsequent inspection and laboratory testing after 2 to 4 years of exposure.

• Field inspection, recovery, and laboratory testing of first generation Clock Spring® installations after 3 to 7 years of exposure. This program yielded the following results:

• Monitoring selected installations with strain gauges showed no loss of reinforcement or system degradation.

• Detailed visual inspection after 2 to 7 years of exposure showed no evidence of degradation or loss of serviceability.

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• Laboratory analysis of Clock Springs removed from service after 2 to 7 years of exposure showed the following:

• The buried composites did not diminish in strength. • The residual strength of test specimens under 15 to 20 ksi constant tensile

load showed no measurable loss of strength or degradation. • The residual strength of Clock Spring® composite after 2 to 4 years of

exposure was higher than the initial laboratory worst-case samples. • There is no deterioration of the resin matrix or glass fibers. • Physical properties of the composite and adhesive did not change with

exposure. • Chemical evaluation showed no evidence of chemical breakdown. • Lap shear strength of the adhesive was not affected by long-term exposure to

field conditions. The conclusion drawn from this extensive battery of tests was that Clock

Spring® repair technology could be used to permanently repair pipeline defects.

Clock Spring® repairs, properly installed, will not fail because of exposure to the environment. The conservative estimate of life is a minimum of 50 years. This is fully documented in a number of technical reports.




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CLOCK SPRING® Application Note Riser Repair Clock Spring® composite repairs are used to repair risers and piping on offshore platforms. The ease of installation, requiring no "hot work", makes Clock Spring® a very attractive repair alternative. The installation procedures are identical to on-shore application with the exception of vertical risers. Risers are repaired in the same manner as horizontal pipe with the Clock Spring® being held in position by support blocks secured to the pipe under the repair. As with other Clock Spring® repairs, the repaired area is stronger than new pipe. The repairs are effective, economical and safe.




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30” GAS RISER REPAIR

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30” GAS RISER REPAIR

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30” Gas Riser Repair

8” RISER REPAIR

Fig 1: Top Section Fig2: Bottom Section 2 Overlapping coils used to reinforce 2 x 6” wide coils used to flange. reinforce mitered girth weld.

Fig 3: Completed Repair

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8” Riser Repair

SNAP WRAP INSTALLATION

Thoroughly mix the two component filler and adhesive.

Apply filler material to defect area and adhesive to pipe surface.

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Snap Wrap Installation

Snap on first layer and apply Snap on each layer. Keep applying adhesive. adhesive.

On completion of eighth layer, apply Tighten and leave to cure. hose clamps.

COMPLETE INSTALLATION CAN BE COMPLETED WITHIN 15 - 25 MINUTES.

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Completed 6” Snap Wrap Repair in UK Refinery

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Completed 6” Oxygen Line Repairs in UK Process Plant

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Completed 6” Oxygen Line Repairs in UK Process Plant

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Completed 6” Oxygen Line Reairs in UK Process Plant

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18” Snap Wrap Repair


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PIPE SUPPORT INSTALLATION

Raise pipe from support and prepare Thoroughly mix the two component filler the surface. and adhesive.

Apply filler material to defect area and adhesive to pipe surface.

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Pipe Support Installation

PIPE SUPPORT INSTALLATION CONTINUED

Snap on first layer and apply adhesive. Snap on second layer.

Tighten and leave to cure. Completed repair/support.

Complete installation can be completed within 10 – 15 minutes.

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Pipe Support Installation (continued)

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18” PIPE SUPPORT

3 x 18” repairs made in support locations. Pipe could not be raised so blocks were inserted and the supports were cut away. Pipe was hand prepared to remove all traces of

zinc paint and any corrosion scabs. The 3 repairs were completed within 2 hours.

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18” PIPE SUPPORT



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18” PIPE SUPPORT



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18” Pipe Support

MULTIPLE BRIDGE CROSSINGS REPAIRED WITH CLOCK SPRING® PIPE SUPPORTS

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LEAK STOP INSTALLATION

1. Locate hole and plug the leak to reduce/stop any flow. Prepare pipe surface. 2. Thoroughly mix 2 part Metalplastic.

3. Using a metal plate, clamp the Metalplastic over the hole and leave to cure for approximately 15-20 minutes.

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Leak Stop Installation

LEAK STOP INSTALLATION CONTINUED

4. Thoroughly mix the two component filler and adhesive.

Apply filler material over the metal plate and apply adhesive

to pipe surface.

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Leak Stop Installation (continued)

LEAK STOP INSTALLATION CONTINUED 6. Snap on first layer and apply adhesive. 7. Snap on each layer. Keep applying

adhesive.

8. On completion of eighth layer, apply 9. Tighten and leave to cure. hose clamps.

Complete installation can be completed within 15 – 25 minutes.

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Leak Stop Installation (continued)

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Pipe SupportCCLLOOCCKK SSPPRRIINNGG®®

Pipe Support The Fast, Economical Solution for Low Pressure

Pipeline Repair

3 x 18” repairs were made in support locations.

The Pipe could not be raised so blocks were inserted and the supports were cut away. The pipe was then hand prepared to remove all traces of zinc paint

and any corrosion scabs.

The 3 repairs were completed within 2 hours.

FOR FURTHER INFORMATION ON CLOCK SPRING® REPAIR SOLUTIONS CONTACT: Clock Spring Company, L.P.

14107 Interdrive West, Houston, TX 77032Telephone: 281-590-8491 • Facsimile: 281-590-9528

Email: [email protected]

CCLLOOCCKK SSPPRRIINNGG®® Pipe Support

The Fast, Economical Solution for Low Pressure Pipeline Repair








CCLLOOCCKK SSPPRRIINNGG®® Pipe Support

The Fast, Economical Solution for Low Pressure Pipeline Repair








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Composite Repair System for Riser Applications







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Snap Wrap Offshore Extended Version/Structural Repair

www.clockspring.com [email protected]

[email protected]

Snap Wrap Offshore Extended Version/ Structural Repair

Location: Middle East Pipe Details: 14” heavy wall structural cross member. 8 metre repair length. Repair Application: Severe external corrosion (up to 80%) metal loss on structural member designed to hold riser support clamps. Engineered heavy wall composite sleeve, manufactured in 600mm widths using bi-axial glass architecture. Extensive filler application and molding to rebuild pipe surface to original outer diameter and sleeves installed and cut to length in a brick wall fashion. Once completed riser holding clamps reinstated over the repair area.

Riser holding clamps reinstated onto repair

and riser

Pipe cleaned and showing severe external corrosion

Repair sleeves installed

Sealing of completed repair area prior to corrosion

coating application

CCLLOOCCKK SSPPRRIINNGG®®

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Contour & Snap Wrap Combination Offshore Riser Repair


[email protected]

Contour & Snap Wrap Offshore Riser Repair Combination Location: Malaysia Pipe Details: 12” diameter with back to back bends. 40 bar operating pressure. 35C operating temperature. Defect Details: External corrosion with severe pitting up to 60% wall loss.

Repair Application: The riser is cleaned via grit blasting to a SA 2.5 standard. The defects are identified and marked. The defects, which are concentrated within the bends are first repaired with Snap Wrap. The Snap Wraps are in 3” wide strips and installed in a “lobster back” format for a combined length of 1.8 metres. Clock Spring Contour was then used to overwrap the total riser length of 5 metres. The repair is designed to last for 20 years. Repair Time: 1.5 days on-site for the complete application with the line remaining in service.

Riser with localised pitting

Installation of Snap Wrap & Contour

Riser repair before and after Contour installation

Riser repair before and after Contour installation


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Clock Spring Offshore Riser


[email protected]

Clock Spring Offshore Riser

Location: West Malaysia Pipe Details: 8” diameter 40 Bar operating pressure 30°‐ 40°C ambient temperature Defect Details: Extensive external corrosion up to 82% wall loss covering circumferential area, especially at the mean sea level (splash zone). Repair Application: Clock Spring reinforcement sleeve with marine type chemicals utilised. These chemicals have been tested for sub‐sea application and will cure even when submerged. The total length of riser being repaired is 5.2 meters. Repair Time: Installation was completed within 9 hours, spanning 1 ½ days. The splash zone section of the riser was repaired within one hour as the crew only had a one hour window at low tide.

Completed repair

Coil installation in progress

Installation included girth welds. Repairs

submerged due to tide

5 metre total section repair


Date post:	17-Feb-2016
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