Notes for a Successful Composite Repair

In order to determine a suitable composite repair solution, the operator should provide the following information:

• Pipeline design and operating pressure;
• Pipeline design and operating temperature;
• Pipeline medium;
• Required lifetime of the repair.

Documentation Requirement for Various Operating Conditions

Basic material documentation

Basic material documentation including Technical Data Sheet, Material Safety Data Sheet should be provided by the supplier. Basic data on material chemical compatibility with the working environment should also be available.

Design capability

Organisations who offer a repair option for pressurised parts need to have an understanding of the design issues associated with their product and be able to provide Engineering Calculations with supporting data. Suppliers must have a competent engineering capability.

Surface Preparation

Surface preparation is one of the single most important aspect to determine the quality and success of the pipe repair. The durability of a bonded assembly under applied load is determined to a large extent by the quality of the surface preparation used. For the higher specification duties and for those that are critical to safety, a surface treatment is recommended to promote bonding and to retain its integrity over the required operational period. Details of surface preparation and implementation procedure and standards required should be specified.

Short-Term Test Data

Short term test data should include tensile strength and modulus values in both the hoop and axial directions of the repair. For permanent and medium/ high pressure (> 5barg) loads bond strength tests to demonstrate the efficacy of the chosen surface preparation methods should also be carried out.

Long-Term Durability Data

Satisfactory designs can be achieved for pressures up to 20 barg based on short-term data that has been adjusted by a suitable factor. However, for safety critical service and the higher pressure duties (up to 50 barg), long-term durability data should be provided to demonstrate fitness for purpose. Long-term effects by fluids and exposure to ultraviolet light should be addressed.

Method of Statement and Risk Assessment

A detailed method of statement and risk assessment of the repair work should be documentation accordingly to each repair scenarios. Proper test procedure and standards should be included and implemented at each stage of repair works to ensure compliance. It is necessary to ensure that product applicators are trained and certified by the supplier.

Implementation Documentation

The applicators for each repair should document the repair works with daily site reports and close-out reports with step-by-step implementation photos.

Health and Safety Documentation

Many of the repair methods involve the handling of chemicals which are inflammable and/or toxic and which pose a hazard to personnel. Assessments should be available for all the chemical species concerned and the material supplier should provide documentation. Due attention to suppliers instructions, the use of simple safety equipment, and good housekeeping is necessary.

Checking Surface Profile Before Composite Repair of Pipeline

After the pipe surface has been prepared according to the required standards; the pipeline surface profile should be measured to ensure that the roughness meets requirement before commencing of composite repair of affected pipeline.

Surface Profile Measurement of Prepared Surface

The type and size of the abrasive used in blast cleaning have a significant effect on the profile or amplitude produced. In addition to the degree of cleanliness, surface preparation specifications need to consider ‘roughness’ relative to the coating to be applied. For example, shot abrasives are used for thin film paint coatings such as pre-fabrication primers, whereas thick or high build paint coatings and thermally sprayed metal coatings need a coarse angular surface profile to provide a mechanical key. 

Inadequate quality control and lack of restriction of large abrasive particle sizes for thin priming coats can lead to peaks of the blast cleaned surface not being adequately covered and may produce rust spots very quickly. The more recently used very high build coatings and thermal-sprayed metal coatings need a large surface area with a high profile in order to ensure that the adhesive bond is greater than the cohesive bond. The difference between these two examples of blast cleaned surfaces is illustrated in the three-dimensional (axonometric) diagrams obtained from a non-contact surface characterisation equipment.

The surface treatment specification therefore should describe the surface roughness required, usually as an indication of the average amplitude achieved by the blast cleaning process. Several methods have been developed to measure or assess the distance between the peaks and troughs of blast cleaned surfaces. These have included comparator panels, special dial gauges and replica tapes. 

To date only the comparator method is referenced as a standard. This method uses a square panel with a central hole surrounded by four segments with different grades of roughness. There is one comparator for grit blasted surfaces and one for shot blasted surfaces. 

The appropriate comparator is placed against the substrate then visual and tactile comparisons are made. The comparators are referred to in ISO 8503-1 Parts 1 to 4, (BS 7079 Parts C1 to C4), ‘Preparation of Steel Substrates before the Application of Paints and Related Products - Surface Roughness Characteristics of Blast Cleaned Steel Substrates’. These standards describe the specification for the comparactors, the method of use and two methods for calibration.

The dial gauge and replica tape methods have been commonly used in the UK. For the dial gauge a calibrated needle gauge is first set to zero on a smooth surface and then the gauge is positioned at several points on the steel surface to measure the depths in the profile. Average readings are obtained.

The replica tape method comprises the use of a two layer plastic film, one compressible, one 50 micron thick incompressible layer and a specially adapted flat anvil dial gauge. The compressible layer is placed on the surface of the blast cleaned steel and is rubbed with a circular ended tool until the surface has conformed to that of the steel, indicated by a uniform dark colouration. The tape is then removed and measured with the dial gauge. 

The maximum profile can then be calculated by subtracting the thickness of the non-compressible backing, i.e. 50 _m from the dial reading. The replica tape method is relatively easy to use especially on difficult to access surfaces of fabricated components. This method also provides a permanent record of the surface roughness. Commercially available tapes are known as ‘Testex, Press - O - Film’. A standard for this method is currently being drafted by an ISO committee. 

If an average profile reading is required, this can be obtained using a portable surface roughness meter that traverses a stylus over the cleaned surface for a defined distance, usually 0.8 mm. These instruments, such as the Talysurf 10, can measure either the arithmetic mean roughness (Ra) or the mean ‘peak to valley’ height (Rz or Rtm), however their short traverse length can only provide an indication of the surface roughness.

More accurate measurements of surface roughness can be obtained from an instrument with a stylus traverse length of 2.5 mm, e.g. the Talysurf 3+ gauge. Whichever method is used to measure surface roughness, inevitably there will be rogue peaks that need to be taken into account. These can be defined as peaks of exceptional height in the blast cleaned surface and are not usually representative but can cause ‘rust rashing’ on primed surfaces where the peaks have projected above the primer coating.

Surface Profile Requirement Before Commencing Composite Repair

It is recommended that the surface roughness be between 60 and 80 microns before composite repair works or surface coating can begin. Once the pipe surface and roughness has been prepared to the required standards, the subsequent composite repair works should commenced within 4 hours.

Surface Preparations for an Effective Anti-Corrosion Coating

Good surface preparation may be considered to be the most important part of the entire coating process in that the greatest percentage of coating failures can be traced directly to poor surface preparation. All paint or anti-corrosion coating systems will fail prematurely unless the surface has been properly prepared to receive the coating. If contaminants such as loose rust, oil, grease, dirt, salts, chemicals, dust, etc. are not removed from the surface to be coated, adhesion will be compromised and/or osmotic blistering will occur in addition to premature failure of the coating in service. No paint or anti-corrosion coating system will give optimum performance over a poorly prepared surface.

Surface cleanliness

The extent to which a surface is made clean before the coating is applied, is a balance between the expected performance of the coating, the paint manufacturer’s recommendations, the time available for the job, the relative cost of the various surface preparation methods available, access to the area to be prepared and the condition of the steel prior to surface preparation. In many instances, coatings cannot be applied under ideal conditions, especially under pipe corrosion repair and maintenance conditions. The quality of surface cleanliness achieved (or it is possible to achieve) will be very different for an un-corroded high quality steel plate with tightly adherent mill-scale, with poorly adherent coating, loose rust scale and heavy pitting. Any substance which prevents a coating from adhering directly to the steel can be considered a contaminant. Major contaminants include:

• Moisture or water
• Oil and grease
• Salt and other Ionic species from the nearby sea and industrial areas
• White rust (zinc salts from weathered zinc silicate shop primers)
• Weld spatter
• Weld fume
• Cutting fume
• Burn through from welding on the reverse side of the steel
• Dust and dirt from the yard site and from neighbouring industrial processes

In maintenance and repair situations, the presence of pitting, corrosion products, cathodic protection products, aged coatings and trapped cargoes, etc., must also be considered, particularly if only localized surface preparation of the most severely affected areas is being carried out prior to re-coating.

Surface cleaning and conditioning

There are many methods available for cleaning and preparing steel surfaces prior to painting. The choice of preparation method will depend upon the repair areas to be prepared and the equipment available. On board maintenance may involve abrasive or water blasting, power and/or hand tool preparation depending upon the size and location of the area to be prepared and painted. As with edge preparation, a higher standard of surface preparation will result in a longer and more effective coating performance.

One of the major causes of coating blistering is the presence of retained soluble material, such as salt, on metal surfaces before painting. While salts are easily removed from flat surfaces by water washing, it is the salts which become trapped in cracks in the coating, under old paint and rust and in pits in the steel surface that are more difficult to remove and can be problematic. Such residual salts will cause blistering or detachment of the new coating, if not removed. High pressure water washing will remove the majority of these trapped salts, if carried out effectively.

Solvent cleaning

This is a process of using solvents or other cleaning compounds, to remove oil, grease and other similar contaminants. This process is best utilized as a preliminary step in the total surface preparation procedure, since subsequent cleaning processes, such as abrasive blasting, may simply spread some of the contaminants more thinly over the surface rather than completely removing them.

Although widely used, solvents are not necessarily the preferred cleaner recommended by paint companies for large areas of contaminants, as they may become an impediment rather than a help if not properly removed. A proprietary, water soluble, oil and grease remover followed by plentiful fresh water washing would be the preferred method of achieving this standard. Care must be taken that the cleaner does not leave any ionic residues on the surface, particularly if the fresh water washing is limited to the use of buckets of water and cloths.

If solvent cleaning is chosen then safety is very important. Adequate ventilation and minimizing potential fire hazards are paramount. Clean-up rags should be changed often to prevent smearing, and two or three solvent applications may be necessary. Brush application should be avoided, or the oil will simply spread over a larger area.

Abrasive blasting

This is the most commonly used method of preparing a surface for the application of. When properly carried out, abrasive blasting removes old paint, rust, salts, fouling, etc., and provides a good mechanical key (blast profile) for the new coating. The surface should be degreased if necessary before abrasive blasting. Weld spatters and deposits should also be removed before blasting. After the abrasive blasting is completed, the surface must be cleaned to remove loose debris and dust before painting commences.

Blast profile

It is important that the correct blast profile is achieved before the substrate is coated. Paint manufacturers should specify the blast profile for each coating, in terms of the anchor pattern required for that paint. In general, thicker coatings will require a profile with a greater peak to trough measurement than a thin coating. If too high, a blast profile is produced. Inadequate coating coverage will result over any high and sharp peaks and this could lead to premature coating breakdown. However, abrasive blasting can also result in an insufficient surface profile and may simply re-distribute contamination over the steel surface trapping contaminants under the surface.

If the blast profile is too shallow or the surface is insufficiently blasted to produce a uniform blast profile, the adhesion of the coating to the metal will be reduced and early failure in service can result. There are several methods for assessing the blast profile characteristics, such as test tapes, comparator gauges, rugotest gauges, etc. If the blasting media is contaminated, the quantity of soluble salts remaining on the steel surface after blasting can be higher than before blasting. The quantity of soluble salts in blasting media can be checked by aqueous extraction techniques.

Soluble contaminants remaining on a surface should be quantified using commercially available tests to ISO 8502-6 and further surface preparation work should be carried out, if necessary, until the specified cleanliness standards are achieved.

Spot blasting

Spot blasting is an abrasive, localized preparation process commonly used during repair and maintenance work, when patches of localized corrosion have occurred. Care must be taken to avoid the following problems:

• Undercutting and loosening of paint edges around the cleaned spot.
• Stray abrasive particles (ricochet damage) will damage surrounding paint in confined spaces and this must be treated and repaired as necessary.

Blasting should be discontinued when moving from one spot to the next rather than trailing blast media over the surface. Any damage caused in this way should be repaired.

Sweep blasting

A jet of abrasive is swept across the surface of the steel rather than being focused on one area for any period of time. Its effectiveness depends upon the type and particle size of the abrasive used, the condition of the surface and the skill of the operator. Three major types of sweep blast are in common use:

• Light sweeping is used to remove surface contamination or loose coatings. It is also used for etching of existing coatings to improve adhesion. Fine abrasive (0.2-0.5mm) is commonly used for light sweep blasting.
• Heavy or hard sweeping is used to remove old coating, rust, etc., back to the original shop primer or bare steel.

Hydro blasting/water jetting

While dry abrasive blasting is the most commonly used method of surface preparation, government and local regulations are continuously changing and require the development of more environmentally-sensitive and user-friendly methods of surface preparation. The use of hydro blasting (also known as hydro jetting, water blasting and water jetting) is becoming an increasing viable means to accomplish this. ASTM F20-16-00 (2006), SSPC-SP12 and NACE No.5 all include information on water jetting. It should be noted that water blasted surfaces are visually very different from those produced by abrasive cleaning or power tools and surfaces often appear dull or mottled after the initial cleaning is completed. 

One drawback of water blasting is the formation of flash rust (also called flash back or gingering) after blasting. Heavy rust formed in a short time period is indicative of residual salt on the steel and re-blasting is necessary before painting. Light rusting is generally acceptable to the paint manufacturers, subject to the coating to be applied and the area in which it will be used. Water blasting does not produce a profile on the steel surface as compared with abrasive blasting. It does however remove rust and loose paint, as well as soluble salts, dirt and oils, from the steel to expose the original abrasive blast surface profile plus the profile produced by corrosion and mechanical damage. The use of ultra-high pressure water blasting can also remove adherent paint from steel.

The terms water washing (usually used to remove salts, slimes and light fouling from vessels in dry dock) and water blasting (used to remove rust and paint) can easily become confused. To clarify the situation, the following pressure guidelines are given:

• Low pressure water washing/cleaning: pressures less than 1,000 psi (68 bar)
• High pressure water washing/cleaning: pressures between 1,000 and 10,000 psi (68-680 bar)
• High pressure water blasting: pressures between 10,000 and 25,000 psi (680-1700 bar)
• Ultra high pressure water blasting: pressures above 25,000 psi (1700 bar).

Most machines operate in the 30,000 –36,000 psi (2000-2500 bar) range Inhibitors can sometimes be added to the water to help prevent flash rusting prior to coating being applied, however they are often ionic in nature and must be completely removed by further washing before the paint is applied. It is also important to ensure that the water being used should be sufficiently pure so that it does not contaminate the surface being cleaned. The use of slurry blasting, where an abrasive is included in the water stream, is also popular in some locations. This has the advantage of producing a profile on the steel as well as washing away soluble salts.

Power tool cleaning

The effectiveness of cleaning using power tools rather than abrasive or water blasting methods depends on the effort and endurance of the operator as working above shoulder height is especially tiring. Some of the more popular methods are as follows:

(1) Rotary power disking

This one is the most commonly used surface preparation methods for maintenance situations. It is also widely used at new installation for the preparation of welds and cut edges prior to painting. Normally, silicon carbide disks are used and the grade selected to suit the conditions of the surface to be abraded. It is important to change the discs at regular intervals in order to maintain efficiency. Care should be exercised in the selection of the grit size and type of disk to be utilized, so that the surface is not excessively smoothed, thereby reducing the ability of the paint to adhere. Irregular and pitted surfaces may require a combination of the various power tool cleaning methods to maximize effectiveness.

(2) Mechanical de-scaling

Needle guns, Roto-Peen and other pounding-type instruments are effective to some degree in removing thick rust and scale and are frequently used. The action of these types of devices is dependent upon cutting blade or point pounding the surface and breaking away the scale. Cleaning is only effective at the actual points of contact. The intermediate areas are only partially cleaned, because the brittle scale disintegrates, but the lowermost layer of rust and scale remains attached to the substrate.

(3) Rotary wire brushing

This method has some merits, depending upon the condition of the surface. Loose “powdery” rust can be removed, but hard scale rust will resist the abrasion of the wire bristles. When rust scale is intact and adherent to the substrate, rotary wire brushing tends to merely burnish or polish the surface of the rust scale, but does not remove it. Care should be exercised, in that the burnished surface may give the appearance of a well cleaned surface, which is often misleading.

(4) Hand tool cleaning

This method is the slowest and usually the least satisfactory method of surface preparation. It is frequently used in confined areas where power tool access is not possible. Scrapers, chipping hammers or chisels can be used to remove loose, non-adherent paint, rust or scale but it is a laborious method and very difficult to achieve a good standard of surface preparation. Wire brushing can make the surface worse by polishing rather than cleaning the rusted surface. Soluble salts, dirt and other contaminants are frequently trapped and over-coated, leading to early paint breakdown.

Pickling

In new building shipyards, an acid pickling process can be used for the preparation of small items before coating. The items, such as pipes, are alkali cleaned followed by a wash and then an acid pickling bath to remove rust. Thorough washing must take place to remove all the acid, particularly if the item is to be painted.

Preparation of non ferrous metals

(1) Galvanized steel

The surface must be dry, clean and free from oil and grease before painting. Degreasing requires some effort to obtain a clean surface, as the zinc corrosion products can trap grease and other contaminants. Any white zinc corrosion products should be removed by high pressure, fresh water washing or fresh water washing with scrubbing. Sweep blasting or abrading are suitable preparation methods, but fresh water washing should be used additionally to remove soluble salts. An etch primer can also be used after cleaning to provide a key for further coatings. Paint companies should be consulted on suitable preparation methods, primers and coatings for galvanized steels and will advise on individual cases.

(2) Aluminum

The surface should be clean, dry and free from oil and grease. Corrosion salts should be removed by light abrasion and water washing. Clean surfaces should be abraded or very lightly blasted using a low pressure and a non-metallic abrasive (e.g. garnet). Alternatively, a proprietary etch primer should be used to provide a key for subsequent paint coats. Paint companies should be consulted regarding suitable primers and coatings.

Factors Influencing Rate of Corrosion

There are several factors influencing the rate of corrosion including diffusion, temperature, conductivity, type of ions, pH value and electrochemical potential. The rate of corrosion can be controlled or reduced by applying anti-corrosion coatings or corrosion protection techniques including composite repair compounds, metal repair putties with metal putty and reinforcement wrap. We shall explore the different factors contributing to the corrosion rate here.

Diffusion

In the majority of cases, the corrosion rates of metals are controlled by the diffusion of reactants to and from the metal surface. Freshly exposed bare steel surfaces will corrode at a greater rate than those covered with a compact layer of rust. The corrosion rate is also heavily controlled by the diffusion of oxygen through the water to the steel surface. In areas where oxygen diffusion is prevalent, corrosion appears to occur at faster rates. High flow areas, such as in the vicinity of bell mouths, will tend to exhibit higher corrosion rates because of the increased oxygen levels, although erosion is also a factor. Areas covered by a thin, conducting water moisture film will corrode faster than areas under immersion.

Temperature

As corrosion rates are determined by diffusion, diffusion rates are also controlled by temperature. Steel and other metals corrode at faster rates at higher temperatures than at lower temperatures. For example, corrosion rates in the cargo tanks will also be higher due to the increased temperature.

Conductivity

For corrosion to occur there must be a conductive medium between the two parts of the corrosion reaction. Corrosion will not occur in distilled water and the rate of corrosion will increase as the conductivity increases due to the presence of more ions in the solution. The corrosion rate of steel reaches a maximum close to the normal ionic content of sea water. Fresh water corrodes steel to a lesser extent than brackish or estuarine water, with sea water usually being the most corrosive to steel.

Type of ions

Some types of ions present in sea water or in cargoes are more corrosive than others. Chloride ions are usually the most destructive with sulfate and other sulfur containing ions also presenting major problems. Chloride ions have a destructive effect on the protective properties of any rusts produced by preventing the formation of the more protective, densely packed oxides. Sulfur containing ions become involved in additional electron generating reactions within the rust itself which in turn forms a cyclic, self-regenerating process.

Acidity and alkalinity (pH)

pH is a measure of the acidity or alkalinity on a scale of 1 to 14. pH 7 is neutral. In neutral sea water, the pH is around 7.5 which mean that the hydrogen ions (acid) and hydroxyl ions (alkali) are almost in balance. Under such circumstances, the reaction that balances the iron dissolution is the reduction of dissolved oxygen to form hydroxyl ions. If however the environment becomes more acidic and the pH falls closer to 1, then there is a greater quantity of hydrogen ions than hydroxyl ions present in the solution. The excess hydrogen ions can become involved in the balancing (cathodic) reaction which results in the evolution of hydrogen gas. As both the hydrogen ions and the hydrogen gas can diffuse very rapidly, the steel can corrode faster. This is a common effect when carrying cargoes such as pet-coke, sulphur and sour crude oils. Under alkaline conditions, where there is an excess of hydroxyl ions and the pH levels tend towards 14, steel cannot corrode and remains unaffected.

Electrochemical potential

Every metal takes up a specific electrochemical potential when immersed in a conducting liquid. This potential is called the half-cell potential as it can only be measured by comparing it to another known reference potential produced by a reference electrode. Common reference electrodes are the Saturated Calomel Electrode (SCE), silver/silver chloride and copper/copper sulfate reference electrodes. The potential that a metal takes up in a solution can determine if and how fast it will corrode. The potential can be changed by connecting it to another dissimilar metal (as in galvanic corrosion or by using sacrificial anodes) or by applying an external potential.

Pipe and Leak Repair Kit

Within industry, piping is a system of pipes used to convey fluids (liquids and gases) from one location to another. The engineering discipline of piping design studies the efficient transport of fluid.

Leak Repair Kit

There’s nothing worse than seeing a pipe leak.  From pinhole water leaks to corrosive chemical leaks. The leak repair kit alleviate your concerns. These kits comprises of highly efficient tools and essential elements that help in repairing the leakage problems. These kits are manufactured using quality tested material thus making these in tandem with the standards of the market.

Keep leak repair kits on hand for temporary repairs. They can be used for longer-term repairs, or for corrosive chemical environments.  There are many kinds of leak repair kits available in the market. They are fast, easy to use, durable, and cost-effective leak repair system.

Pipe Repair Kit

The pipe repair kit features:

• Permanently repair most pipes/fittings or hose in minutes
• Applies like tape, sets like steel
• Works on pipe of nearly any material, including copper, steel, plastic, cast iron, rubber
• Includes everything you need but water - No tools needed!

Kit includes:

• foil packed resin tape
• protective gloves
• application lubricant
• installation instructions

There are some emergency pipe repair kits available in the market. This is an all-inclusive emergency response kit that enables immediate action when situations demand it. A wrench and water are all that’s needed to use. It is versatile and can be used for hazardous and non-hazardous chemical service.

If you ever have to perform an emergency repair on a broken pipe, you will truly appreciate this unique pipe repair product. Without the use of tools, you can repair the break or leak in your copper, steel, plastic, cast iron, or rubber pipe - in minutes.

Metal Putty

The product overviews of metal putty are:

• Steel reinforced metal epoxy putty
• Sets steel hard in 10 minutes and can be used underwater
• Can be drilled, tapped, filed, machined, sanded and painted once dry

Uses:

• Suitable for use with metals and most other types of material

Composite Wrap

Composite wrap is a permanent, cost-effective pipeline repair technology, suitable for non-leaking defects such as pits, dents, gouges, and external corrosion. Composite wrap can be performed on an operating pipeline without taking it out of service. This repair technique is quick and generally less costly than other repair options, and it permanently restores the pressure-containing capability of the pipe when properly installed. Composite wrap can serve as an alternative to the traditional pipeline repair practices such as pipeline replacement or the installation of full-encirclement steel split sleeves.

Compared to these traditional practices, composite wrap repairs are generally less expensive, time consuming, and labor intensive. is cleaned, and the stainless steel split sleeve is bolted or welded into place. Use of composite wrap as an alternative to pipeline replacement can reduce safety risks, decrease pipeline downtime, save gas for sale, and decrease methane emissions to the atmosphere. Composite wrap systems

Composite wraps are ideal for both internal and external pipe corrosion. Composite wraps offer an ultra fast, reliable and safe solutions for pipeline corrosion issues. ​

Pipe Corrosion Repair

Features

• Dynamically predict corrosion rates using pressure, temperature, wall wetting, and shear rates
• Choose from three commonly used CO2 corrosion models: NORSOK M-506, de Waard 1995, and IFE top-of-line corrosion

Description

• It can predict corrosion rate along a pipeline based on variation in temperature, pressure, flow velocity, and flow regime.

The flow regime supports prediction of oil or water wetting of the pipe wall. Pressure, temperature, liquid flow velocity, condensation rates, and wall shear stress calculated by the flow model feed the corrosion rate calculations. Identifying potential points of corrosion along pipelines is critical to maintaining safe operations and to anticipating upcoming maintenance.

Pipe Reinforcement

Pipe reinforcement is made to last for a very long time. Reinforcement pipes are manufactured in many different types and sizes, and for many different uses. They are tough to withstand long jacking drives. The materials used are trusted for extreme strength and longevity. The pipes are made with confidence for storm water, gravity pressure/sewer, raw water, potable water delivery, and many other applications.

What Are The Uses And Applications Of Metal Putty For Products And Industries

Metal putty is suitable for use with metals and most other types of material. The uses and applications of metal putty for metal repair compound are:

For Steel Repair Putty

Features

• Metal filled two-component epoxy putty
• Bonds to metal, concrete, plastic
• Cures at room temperature
• Can be drilled, tapped, machine or painted
• Excellent resistance to oil, gasoline, water and chemical
• Ideal for patching and repairing areas where welding or brazing is undesirable

Application

• Suitable for repairing defects and rebuilding of steel and iron casting parts
• Recommended for repairing and rebuilding of worn components such as bearing and fan housing

Aluminium Repair

Features

• Aluminium-filled  two-component epoxy putty
• Repairs to non-rusting aluminium castings, machinery and equipment
• Excellent resistance to chlofluorocarbons
• Bonds to aluminium and other metals
• Fills porosity in aluminium castings
• Can be drilled, tapped, machined or painted

Application

• Used for rebuilding of various aluminium casting parts
• Used for repairing aluminium casting air holes and sand holes, shrinkage and cracks
• Used for filling oversize, scratch or damaged repairing
• Applicable to general machines, automobiles, airplanes, watercraft etc

Bronze Repair

Features

• Bronze -filled two-component epoxy putty
• Repairs to bronze and brass bushings, shafts, castings and parts
• Repairs and rebuilds area where brazing is undesirable or impossible
• Bonds securely to bronze alloys, brass, copper and ferrous metals
• Can be drilled, tapped, machined or painted

Application

• Used for rebuilding and repairing of various bronze casting parts
• Used for repairing bronze casting air holes and sand holes, shrinkage and cracks
• Used for filling oversize, scratch or damaged repairing
• Applicable to watercrafts, machines, automobiles, mining machineries etc

Stainless Steel Repair

Features

• Stainless steel-filled two-component epoxy putty
• Patch, repair and rebuild stainless steel parts and equipment
• Bonds to ferrous and non-ferrous metals
• Non-rusting

Application

• Used for repairing stainless steel and steel parts defect repairing and worn part rebuilding
• Applicable to watercrafts, machines, automobiles, mining machineries etc

Underwater Repair

Features

• Ceramic-based two-component epoxy putty.
• Suitable for moist and wet conditions
• Excellent resistance to oil and chemicals
• Bonds to metallic and non-metallic surfaces
• Fills porosity and cracks on valves and pump bodies
• Can be drilled, tapped, machined or painted

Application

• Used for repairing pipeline, valve, pump shell, tank body and concrete under emergency
• Used for leakage stopping for water machineries, watercrafts repairing, mines and buildings etc
• Used in splash zone repair in combination of SealXpert Fiberglass Repair Tapes

Steel-Filled Repair

Features

• Fast-curing
• Stainless steel-filled two-component epoxy putty
• Suitable for quick and emergency repairs
• Cures in less than one hour
• Can be drilled, tapped, machined or painted

Application

• Used for emergency and quick repairing of steel, iron, stainless steel etc. metal damaged parts, worn parts and leakage
• Applicable to watercrafts, machines, automobiles, mining machineries etc

High Temperature Repair

Features

• Withstands high temperature up to 230 °C (446 °F) (continuous) and 280 °C (536 °F) (intermittent)
• Nickel alloy-filled two-component epoxy putty
• Suitable for engine parts repairs
• Can be drilled, tapped, machined or painted

Application

• Used for repairing abrasion, scratch, and crack etc. on equipment operating at high temperature
• Applicable to watercrafts, automobiles, machineries in petrochemical, power plant etc

Super-Metal Epoxy Putty

Features

• Alloy and ceramic filled two-component epoxy putty
• Excellent hardness
• Cold welding repairing material
• Versatile durable repair composite
• Outstanding adhesion to all metals
• Excellent corrosion resistance
• Superior chemical resistance
• Can be drilled, tapped, machined or painted

Application

• Suitable for repairing worn rotating shafts
• Applicable for making repairs that can be precision machined

Titanium Repair

Features

• Titanium filled two-component epoxy putty
• High performance
• Excellent chemical resistance
• Withstands heavy loads in harsh chemical environments
• Can be drilled, tapped, machined or painted

Application

• Suitable for repairing and rebuilding on load bearing components
• Applicable for repairs to machineries and equipment that can be precision machined

The metal putty products have been designed for application in the various types of industries. They are specifically designed to provide wear, erosion and corrosion protection and chemical resistance under high operating pressure and temperatures. The products extend the lifespan of these critical assets while reducing down time.

The various types of industries are :

1 Oil & Gas Industry

2 Chemical & Petrochemical Industry

3 Marine & Offshore Industry

4 Pharmaceutical & Food Industry

5 Power Generation Industry

6 Semiconductor & Electronics Industry

7 Buildings & Facilities Maintenance Industry

8 Mining & Metals Industry

What Are The Uses And Benefits Of Composite Wrap For Pipeline Defects

Composite repair systems using composite wrap remain a constant repair option for industries requiring the repair and rehabilitation of piping systems. Various techniques and testing methods, which have the ability to handle different critical conditions onsite, are being developed in order to meet the demands of the industry. Composite wrap materials are recognized as a reliable and effective means of repairing corrosion damage, mitigating corrosion concerns and keeping critical piping systems in production.

When left unmonitored, excessive external corrosion, internal corrosion, erosion, abrasion, dents and cracks can all potentially lead to disaster. These pipeline defects if not repaired, can cause expensive and potentially deadly consequences to asset owners and equipment operators. Therefore, these pipeline defects require suitable repairs or replacements, depending on the severity of the defects.

Safer Solution to Repair of Pipeline Defects

Composite wraps have been used as transmission pipeline repair methods for more 20 years. Within that time frame, specific composite repair systems have proven to be a permanent repair of potentially catastrophic pipeline defects. Along with the guidelines issued for non-metallic repairs to pipelines in ASME PCC-2 Article 4.1, composite repair manufacturers design composite repairs solutions for specific field applications.

Fundamentals of composite repair systems

While operating pressure is not always high, the chemicals and the elevated temperatures of some piping processes accelerate internal and external corrosion. In most cases, wall loss is severe and in many cases, it has become a safety hazard or is leaking. Through wall defects or complete wall loss and pinhole leaking is a regular occurrence within many facilities. In order to repair these types of defects, a composite system must meet the minimum requirements and perform at the expected level under extreme conditions. Whilst numerous composite wrap materials are available on the market, there are few that have the testing and capability to perform at the elevated temperatures that may be experienced.

Types of composite repair systems

Layered systems and wet lay-up systems are general types of repair systems used for composite repair. The wet lay-up system involves pre-impregnated fibreglass cloth that is activated in the flied by water. An advantage of this system is that the cure state tends to be monolithic and can be used to cover a range of geometries, including tees, elbows, bends and even valves. When designing a repair system using composite wrap materials, engineers must consider both strength and stiffness. From a composite standpoint, strength relates to the tensile strength of a particular system, while stiffness relates to elastic modulus. For most conventional repair systems, there is a direct correlation.

Composite Repair System Uses and Benefits

Composite repair systems are suitable for use on pipeline defects including wall loss of up to 80 percent (e.g. external or internal pipe corrosion, erosion etc.), dents and gouges in pipes and pipe fittings. The composite repair solution is considered a replacement option to the crop-and-replace method of replacing a new pipe section.

There are many advantages of composite repair including:

(1) Able to installed while the pipeline is operation
(2) Operating pressure may not need to be reduced during repair works
(3) No hot works required to install the composite repair systems
(4) Remediate, repair and reinforce the pipe defects by increasing wall thickness
(5) Reduce unnecessary heat infected zone weld induced stresses induced from welding
(6) Versatile for application on complex pipe geometries (e.g. elbows, tees, nozzles and bends)
(6) Faster project implementation duration
(7) Economical repair solution