Composite wrap pipeline repair

Composite wrap pipeline repair is an advanced trenchless technology used to reinforce and rehabilitate pipelines that have developed leaks or defects over time. This type of repair involves applying fiber-reinforced polymer (FRP) composite materials, such as carbon fiber or glass fiber, onto the external surface of the pipe to seal leaks and restore strength. Composite wrap pipeline repair offers major benefits compared to traditional repair methods like welding, clamping, or full pipe replacement:

Cost-effective: Composite wrap repairs cost 50-80% less than pipe replacement. Only the damaged section needs repair rather than the whole pipeline.
Time-efficient: Installation is 5-10 times faster than pipe replacement. Repairs can often be completed without stopping pipeline operation.
Trenchless: Requires no excavation or destruction which minimizes public disruption.
Durable: Restored pipelines last 30+ years with minimal maintenance.
Versatile: Effective for many pipe materials like steel, concrete, PVC, fiberglass, etc. Can reinforce bends, joints, cracks, dents, and corrosion damage.

The global composite wrap pipeline repair market was valued at $248 million in 2021. It is projected to reach $344 million by 2028 with a CAGR of 5.0% from 2022 to 2028 according to Reports & Data. This growth is driven by the aging infrastructure around the world and the need for rapid, affordable repairs.

Types of Composite Wrap Pipeline Repair

There are a few main types of composite wrap systems used for pipeline repair and reinforcement:

Epoxy-based systems: Epoxy is combined with fiber reinforcement like carbon or glass to create a solid composite that bonds to the pipe surface. Epoxies cure rapidly to restore strength.
Polyurethane-based systems: Polyurethane resin systems have similar fiber reinforcements as epoxy. Polyurethanes are more flexible and better suited for pipes subject to movement/vibration.
Heat-activated systems: These incorporate a heating source to melt heat-activated resins like polyethylene so they flow into the fiber wrap. No catalysts or curing compounds needed.
UV light-cured systems: The resin cures rapidly with UV light activation instead of traditional curing compounds. Allows for a faster installation.

The table below compares some pros and cons of each type:

Type of System	Advantages	Disadvantages
Epoxy	High strength, rapid installation, low cost	Brittle, short shelf life, temperature sensitive
Polyurethane	Flexible, tolerant of pipe movement	Moisture sensitive, expensive
Heat-activated	No curing compounds or catalysts needed	Requires heating equipment, slower installation
UV light-cured	Extremely rapid curing, low temp application	Requires UV lights, limited thickness/strength

Real-World Examples:

An 18” steel gas pipeline in Egypt was suffering external corrosion damage. It was reinforced structurally using a heat-activated polyethylene wrap system. This avoided the need to stop gas flow during $2 million pipeline replacement.
A 24” PVC sewer pipe in Los Angeles had multiple leaks near joints caused by seismic activity. Crews repaired a 75 ft. section using a UV light-activated vinyl ester composite wrap without trenching or stopping sewage flow.
In Australia, concrete penstock pipes feeding hydroelectric turbines were reinforced using an epoxy/carbon fiber structural wrap to extend the operating life without costly penstock replacement.

How Composite Wrap Pipeline Repair Works

Composite wrap pipeline repair is completed using the following basic steps: Pipeline wrapping process

Surface preparation: The pipe exterior is cleaned and smoothed to remove loose material, corrosion, or debris that could cause future failure. Often abrasive blasting or grinding is used.
Resin impregnation: The fiber reinforcement is saturated with the selected resin system before application. This “wetting out” removes voids and ensures proper bonding.
Wrap application: The wet resin-impregnated fiber wrap is wrapped tightly around the pipe using a specialized wrapping machine or by hand.
Curing: Resins cure over time, temperature, or with UV light/heat to form a solid barrier. Curing time ranges from 30 minutes to 12 hours.
Testing: Tests confirm that the resin has completely cured and the repair can withstand the operating pressure. Common tests are spark testing, adhesion testing, and hardness testing.

There are a few key factors that determine the performance and longevity of a composite wrap pipeline repair:

Pipe material – Each material has different surface prep needs and requires resin systems compatible with expansion/contraction properties.
Operating temperature – Resins and wraps must be designed to withstand temperature fluctuations from the pipe contents.
Operating pressure – The repair design thickness and strength increases for higher pressure pipes.
Environment – Chemical and corrosion resistance must match the pipe environment. UV resistance is also needed for outdoor pipes.
Application quality – Proper surface prep, resin ratios, wrapping tension, overlap, and curing are critical.

Benefits of Composite Wrap Pipeline Repair

Composite reinforcement is the leading rehabilitation solution for pipelines worldwide because of advantages over other repair options: 1. Cost Savings

Composite repairs cost 50-80% less than full pipe replacement. Only small sections need repair, not the entire line.
Installation rates of up to 150 ft/hr minimize downtime and lost revenue from shutdowns.
Extends asset lifespan so replacement can be deferred 30+ years.

2. Speed

Repairs 5-10 times faster than pipe replacement.
Cure rapidly from 30 mins up to 12 hours for some resin systems.
Often done without stopping pipeline flow.

3. Quality

Restores pipe to full pressure rating and structural integrity.
Withstands up to 80% of new pipe strength.
Maintains performance for 30+ years.

4. Safety

No open flames or hot works permits needed.
No excavation or destruction involved.
Workers avoid risks of trenching like cave-ins or hydrogen sulfide exposure.

5. Minimal Disruption

Avoids public impact from road closures or destroyed landscaping.
Inconspicuous low-profile wrap allows pipes to remain in service.

Challenges and Limitations of Composite Wrap Pipeline Repair

While composite reinforcement offers tremendous advantages, there are some challenges and limitations to consider: Meeting Codes and Standards

Obtaining approval from owners/operators and authorities for permanent repairs. Must comply with codes like ASME PCC-2.
Qualifying personnel and products to required certifications.

Quality Control

Following rigorous surface preparation and installation procedures to avoid future failures.
Ensuring proper resin ratios, impregnation, wrapping tension and overlap.
Confirming complete curing with spark, adhesion, and hardness testing.

Technical Expertise

Design complexity in determining design thickness and materials.
Identifying proper resin for each pipe and environment.
Training competent application crews.

Access Limitations

Available workspace around pipe.
Diameter restrictions from wrapping equipment.
Ability to stop flow during resin curing period.

Costs

Raw material costs fluctuate with oil/gas prices.
Mobilization costs for small repairs.
Costs still high compared to some clamping or welding repairs.

Ongoing research aims to expand the application range of composite repairs by improving UV, fire, and extreme temperature resistance. New automated wrapping systems also seek to reduce labor and costs while maintaining quality.

Composite Wrap Pipeline Repair vs Other Repair Methods

Composite reinforcement offers unique advantages over other pipeline repair alternatives:

Repair Method	Comparison to Composite Wrap
Welding	<ul><li>Slower installation rate</li><li>Higher cost for small repairs</li><li>Stops operation during welding</li><li>High skill requirement</li><li>Not effective for non-metallic pipes</li></ul>
Clamping	<ul><li>Less durable long-term repair</li><li>Often only a temporary fix</li><li>External clamps can shift or corrode</li><li>Not feasible for small pinhole leaks</li></ul>
Lining	<ul><li>Requires flow stoppage</li><li>Difficult on bends</li><li>Less effective for external corrosion</li><li>Short liner life compared to wrap</li></ul>
Pipe replacement	<ul><li>5-10 times slower installation</li><li>Much higher costs</li><li>Trenching impacts public</li><li>Replacement may be unnecessary</li></ul>

Composite wrap reinforcement is often preferred by pipeline owners and operators because it can be installed rapidly under pressure without stops in service. The durable external barrier restores strength and sealing without costly and disruptive pipe replacement. Many other repair methods are only temporary or limited in application.

Composite Wrap Pipeline Repair Applications and Case Studies

Composite wraps have been used to reinforce pipelines worldwide in diverse applications: Oil and Gas Pipelines

An 8” crude oil line in Oklahoma was suffering external corrosion and pitting. A 70 ft. section was reinforced with a carbon fiber/epoxy structural wrap, avoiding a shut down.
A 20” wet gas pipeline in the North Sea was reinforced in subsea conditions using a heat-activated polyethylene wrap system.

Water and Sewer Pipelines

A 48” prestressed concrete cylinder pipe feeding a hydroelectric dam was reinforced using a carbon fiber structural wrap after cracks formed. Outage was avoided.
In the UAE, over 50 miles of sewer pipeline was restored using UV-cured glass fiber vinyl ester wraps without excavation.

Chemical and Industrial Pipelines

Heat-traced chemical lines at a UK refinery were reinforced with a heat-activated wrap to add corrosion resistance without removing expensive trace heating.
Penstock pipes feeding hydroelectric turbines were suffering external corrosion. A polyurethane composite wrap was used to avoid penstock replacement.

Government and Military

On a Navy vessel, 20 ft. of 12” saltwater pipe was reinforced in restricted spaces using a carbon fiber/epoxy wrap to avoid pipe replacement.
At a Department of Energy facility, over 2000 ft. of buried concrete header pipes were reinforced with a heat-activated structural wrap after air test failures.

These applications demonstrate the versatility of composite wrap to rapidly reinforce pipelines of any material in difficult conditions while avoiding replacement. Owners have realized tremendous cost and time savings.

Revolutionize your pipeline repair with our cutting-edge composite wrap solutions! Our method is faster, safer, and more cost-effective than traditional repairs. Say goodbye to costly downtime and hello to restored pipeline integrity with minimal disruption. Visit Composite pipe repair solutions for the future of pipeline maintenance!

Composite Wrap Pipeline Repair FAQs

Here are answers to some frequently asked questions about this trenchless pipe rehabilitation technology:

What is composite wrap pipe repair?

Composite wrap pipe repair is a method used to repair damaged pipelines using composite materials. It involves wrapping fiber-reinforced polymer composites, consisting of high-strength fibers like fiberglass or carbon fiber embedded in a polymer resin matrix, around the damaged section of pipe. The composite wrap provides structural reinforcement and restores the strength and pressure containment capability of the pipe. It can repair defects like corrosion, dents, gouges, cracks, and leaks. Composite wrap is considered a permanent repair method and can extend the service life of pipelines by 20 years or more. Key benefits of composite wrap pipe repair:

Restores pipe to original strength
No hot work required
Quick installation (days vs weeks)
Cost effective compared to replacement
No service interruption
Prevents further degradation

What is composite material for pipeline repair?

The main composite materials used for pipeline repair are:

Fiberglass – Most commonly used. Provides high strength and corrosion resistance. Main options are bi-directional E-glass fabrics or unidirectional S-glass fabrics.
Carbon fiber – Extremely strong and stiff. Used for high pressure applications. More expensive than fiberglass.
Aramid fiber (Kevlar) – Very strong and heat resistant. Often used for high temperature applications.
Resin matrix – Usually epoxy or polyester. Bonds fibers and transfers load. Vinyl ester used for chemical resistance.

The composite fabric gives the wrap its strength and stiffness, while the resin cures and bonds it to the pipe surface. The materials are combined at the job site using a wet layup process. Proper surface preparation and installation per manufacturer specifications are critical for performance.

Can composite materials be repaired?

Yes, composite materials can be repaired using similar techniques to the original fabrication methods. The most common repair methods are: Scarf repair – Damaged area is tapered and layers of composite material are built back up to original thickness. Provides smooth finish. Step repair – Damaged plies are removed and replaced by new materials in single steps. Quick but surface is not as smooth. Patch repair – Precured composite patch is adhesively bonded over damaged area using film or paste adhesive. Resin injection – Low viscosity resin is injected into delaminations or voids and cured. Best for minor damage. Bolted repair – Metal or composite patch secured with bolts/fasteners. Used for thick composites. Bonded repair – Patch co-cured/co-bonded to damaged parent structure. Common for thin skins. The strength and durability of a composite repair depends on proper materials selection, surface preparation, technique, and quality control. Inspections should be performed before and after repair.

How do you fix a broken composite?

Here are the general steps to properly fix a broken composite structure:

Inspect damage – Assess size, depth, affected layers using tap testing, ultrasonics, x-ray, etc.
Remove damaged section – Cut out broken section removing at least 2 plies beyond visible damage. Create tapered scarf edges.
Clean surface – Abrade bonding surface, apply adhesion promoter, remove dust.
Prepare patch – Cut replacement plies of original material, dry fit patch.
Apply adhesive – Mix and apply structural adhesive to bonding surfaces.
Install patch – Position patch on bonding surface, working from one end to avoid air bubbles.
Apply pressure – Use vacuum bag, clamps, or weights to apply steady pressure.
Cure adhesive – Heat cure adhesive per manufacturer instructions.
Inspect repair – Ensure proper bond strength, no gaps or air pockets.
Finish – Sand and refinish outer surface if needed.

Proper materials, repair design, surface preparation and technique are critical to restore strength. Always follow OEM repair manuals. Perform cure and post-cure inspections.

What is the most common method used for composite wrap pipeline repairs in oil and gas industry?

The most common method used for composite wrap pipeline repairs in the oil and gas industry is the wet layup technique using pre-impregnated composite fabrics:

The damaged section of pipe is cleaned and abrasively blasted to create a rough surface profile.
Liquid epoxy is mixed and applied to fill pits, gouges, and provide a smooth surface.
A pre-impregnated fiberglass fabric is saturated with water to initiate resin cure then wrapped circumferentially under tension.
Multiple layers are built up to required thickness, with at least 50% overlap between layers.
The saturated fabric cures rapidly to form a hard, durable composite wrap within minutes.
The wrap restores strength, provides corrosion protection, and prevents further degradation.

Pre-impregnated fabrics like SylWrap make installation much faster. Other methods utilize dry fabrics saturated on-site with two-part resins. Proper surface prep, trained technicians, and QA make this an effective permanent repair.

What are the composites used in pipes?

The main composite materials used in pipes are:

Fiberglass – Most common. Provides corrosion resistance. Used as filament wound pipe or composite repairs.
Carbon fiber – Extremely strong and stiff but expensive. Used for high pressure applications.
Aramid fiber – Very strong and durable. Used for natural gas pipe repairs.
Epoxy resin – Excellent adhesion, chemical resistance, and low shrinkage.
Polyester resin – Fast curing and low cost but lower strength.
Vinyl ester resin – Best corrosion resistance but more expensive.

Pipes may consist entirely of composite materials or use composites to rehabilitate and strengthen traditional materials like steel. The resin matrix binds fibers together and transfers load from the pipe to the reinforcement. Glass and carbon fibers provide exceptional hoop strength to contain pressure. Proper materials selection and design are critical for performance requirements.

What are the advantages of composite wrap pipe repair?

The main advantages of using composite wrap for pipe repair include:

Permanent repair – Restores full strength and containment. Lasts for decades.
No service disruption – Pipe remains in operation during installation.
Fast installation – Wrapping goes quickly compared to welded sleeves or replacement.
Lower safety risks – No hot work, fire hazards, or emissions during installation.
Adaptability – Conforms to complex shapes like elbows, tees, reducers.
Cost savings – Less expensive than pipe replacement or metal sleeves. Saves product loss.
No corrosion – Stops external corrosion and prevents further degradation.
Quality – Consistent fabrication, installed only by certified technicians.

By providing a fast, permanent fix without taking pipelines out of service, composite wrapping delivers exceptional value compared to traditional repair methods. The composite materials are engineered to withstand operating pressures and harsh conditions for decades.

How do you use repair wrap?

Here are the key steps to properly install a composite repair wrap:

Clean pipe surface and abrasive blast to remove corrosion and create surface profile.
Apply adhesive putty to fill pits, gouges, and smooth surface.
Pre-cut fabric to proper dimensions. Pre-mix resin if doing wet layup.
Saturate first layer of fabric with water or resin, wrap under tension.
Apply subsequent layers with >50% overlap to build up thickness.
Use plastic squeegee to remove air pockets and excess resin.
Allow resin to fully cure per specifications before putting back in service.

Proper surface preparation is essential. Wrapping tension, smoothness, and overlap are critical to performance. Always follow the manufacturer’s installation guide. Use trained technicians experienced with wet layup. Inspect the finished wrap using NDT methods.

Can you wrap a pipe to stop it from leaking?

Yes, composite wraps can be used to stop leaks in pipelines without having to take them out of service. Leak repair wraps consist of a flexible putty compound reinforced with high-strength fiber wrap that has excellent sealing and adhesion properties. The key steps for pipe leak wrap repair are:

Clean and abrade surface around leak to create bond
Apply leak sealing putty generously to cover leak
Wrap specialized fiberglass or carbon fabric under tension
Resin saturates fabric and cures rapidly to form hard seal
Additional layers can be added for more severe leaks

The composite wrap reinforces and contains the putty, which seals the leak quickly with minimal downtime or safety risks. It provides a permanent repair solution. Leak repair wraps are commonly used as an emergency pipeline repair technique before corrosion defects grow larger.

How do you use a composite pipe wrap?

Using a composite wrap to repair or reinforce pipelines involves these key steps:

Clean pipe surface by abrasive blasting to near white metal per SSPC-SP10.
Apply adhesive putty to fill pits, gouges, and provide smooth surface.
Pre-cut fabric to proper pipe dimensions. Pre-mix resin if doing wet layup.
Saturate fabric with water or resin. Wrap under tension with 50% overlap.
Use plastic squeegee to smooth layers, remove air and excess resin.
Build up thickness to meet design requirements with additional layers.
Allow resin to fully cure before putting back in service per specifications.
Inspect wrap with NDT methods like ultrasonics, tap testing, X-ray.

It is critical to use qualified personnel experienced with composite wet layup techniques. Strict adherence to surface prep and installation standards ensures optimal performance and containment integrity.

How do you determine if a pipeline is suitable for composite wrap repair?

There are several key factors to consider when determining if a pipeline defect or damage is suitable for composite wrap repair:

Type of damage – Composite wraps are recommended for non-leaking defects like corrosion, gouges, cracks, dents, and defects up to 80% wall loss. They can also temporarily repair internal corrosion.
Pipeline operating conditions – There are typically no pressure limits on composite wrap use. However, some products may have temperature restrictions. The wrap must be compatible with the pipeline contents.
Location and access – Composite wraps conform to complex shapes and require minimal access. They are advantageous where replacement is difficult.
Cost – Composite wraps are generally less expensive and faster to install than cut-outs or welded sleeves, avoiding gas loss and service disruptions.
Lifetime requirements – Properly installed composite wraps provide a permanent repair, restoring pipelines for 20+ years of service.

Detailed measurements, engineering assessments of loads and operating conditions, and manufacturer recommendations should inform final suitability decisions. Software like GRIWrap can aid determinations. In-service testing may be required.

What should you look for when inspecting a pipeline to determine if a composite wrap is suitable?

When inspecting a pipeline to evaluate suitability for a composite wrap repair, key aspects to examine include:

Type, location, length, width, and depth of damage
Percentage of wall loss from corrosion
Presence of cracks, gouges, dents or leaks
Pipe diameter, schedule, and operating pressure
Operating temperature range and chemical exposure
Location of nearby valves, tees, elbows or other equipment
Soil conditions, depth of burial and external loads
Access limitations for installation equipment

Inspection data determines the wrap length, number of layers, resin type, and accessories needed. The wrap must extend past damage on both sides. Non-destructive testing like ultrasonics and radiography informs decisions. If defects exceed 80% wall loss or the pipe leaks, composite wraps may not be appropriate.

What tests need to be performed to qualify a composite wrap system for pipeline repair?

To qualify a composite wrap system for pipeline repair per ASME PCC-2 and ISO 24817, the following performance tests are required: Mechanical properties: Tensile strength, modulus, maximum strain, lap shear adhesion strength, glass transition temperature, etc. Must meet minimum strength and stiffness. Durability testing: Water absorption, cathodic disbondment, hot/wet conditioning, thermal cycling, freeze-thaw, UV exposure. Determines environmental limits. Pressure testing: Hydrostatic burst tests of pipe samples with defects and composite wrap. Must not leak or rupture before meeting criteria. Flaw tolerance testing: Validate performance reinforcing various flaws like corrosion, cracks, gouges. May need defects with cyclic pressure. Field installation testing: Simulate on-site wrapping process to qualify installation manuals and training. Examine workmanship. The system pressure rating is based on the lowest passing pressure test. Performance must be validated under expected operating conditions. Ongoing QA and inspection ensures conformance.

What determines if a composite wrap pipe repair will be successful?

The key factors that determine if a composite wrap pipe repair will be successful are:

Proper materials selection – The composite fibers and resin matrix must be compatible with operating temperatures, chemical exposure, loads.
Adequate surface preparation – Thorough cleaning and abrasive blasting to remove coatings/corrosion and roughen surface.
Quality installation – Strict adherence to manufacturer procedures, trained technicians, proper saturation, wrapping tension, overlap, number of layers.
Suitable cure time – Resin must fully harden before putting pipe back into service per specifications.
Effective QA/QC – Inspection for air pockets, gaps, thickness verification, adhesion testing ensures quality standards.
Periodic inspection – Monitor wrap over time, especially at ends. Repair any damage from backfill immediately.

Following standards like ISO TS 24817 and verifying performance testing gives high confidence in a quality, long-lasting composite wrap repair.

How do you calculate the required thickness and length for a composite wrap pipe repair?

The ASME PCC-2 standard provides a methodology to calculate the required thickness and length for a composite wrap pipe repair:

Determine the remaining strength ratio (RSR) of the damaged pipe section based on depth of wall loss, defect length, pipe geometry and operating pressure.
Calculate the required thickness to provide necessary reinforcement so that the repaired section has RSR ≥ 1.0. The wrap thickness needed is proportional to the defect depth and length.
The circumferential extent of the wrap must extend minimum 50 mm (2 in) past each end of the defect. The total wrap length equals the defect length plus at least 100 mm.
Determine number of plies needed to achieve the thickness using the ply thickness provided by the composite manufacturer. Round up.
Validate the design by hydrotesting and analyze using composite laminate theory. Increase thickness or length if needed.

Software like ArmorPlate’s PipeWrap and online calculators can determine parameters and account for safety factors automatically based on data inputs.

What codes and standards apply to the use of composite wraps for pipeline repair?

The primary codes and standards governing the use of composite wraps for pipeline repair are:

ASME PCC-2 – Repair of Pressure Equipment and Piping
ISO TS 24817 – Petroleum, Petrochemical and Natural Gas Industries – Composite Repairs
ASME B31.4 – Pipeline Transportation Systems for Liquid Hydrocarbons
ASME B31.8 – Gas Transmission and Distribution Piping Systems
CSA Z662 – Oil and Gas Pipeline Systems
49 CFR 192 – US Federal Pipeline Safety Regulations

These provide requirements on materials, design, installation, inspection, and testing. Many pipeline operators also have their own standard repair specifications that reference these codes. Any repair technique must comply with applicable federal, state, provincial and local regulations. PHMSA rules require repairs permanently restore pipe’s MAOP. Documentation, traceability and certified installers are typically mandatory.

Materials Cost

Cost of the composite wrap kit, including fiberglass fabric, epoxy resin, and accessories. Prices vary based on pipe diameter and number of layers needed.
Filler putty for smoothing surface defects.
Surface preparation materials like abrasives for blasting.
Consumables like squeegees, brushes, gloves, etc.

Labor Cost

Hourly wages for composite technicians doing surface prep, installation, and QA inspection.
Additional engineering/project management time. Estimate at 25% of field labor cost.
Account for hands-on installation time plus resin cure time.

Equipment Costs

Rental fees for sandblasting equipment, backhoes for excavation, cranes, etc.
Purchase costs for re-usable tools like wrap tensioners. Spread this over multiple jobs.

Indirect Costs

Permits, inspection fees, non-destructive testing.
Site cleanup, waste disposal fees.
Temporary access roads or shoring if needed.

Comparison to Alternatives

Compare composite wrap installation costs to a cut-out pipe replacement or welded steel sleeve option.

Accurate cost estimates depend on details like pipe diameter, operating pressures, defect length, and site conditions. But this covers the main elements to factor into composite wrap repair costs.