Author: Chemco

Industry:                            

Power Generation

Date:

2015

Substrate:

Critical support structure for 40 year old overhead pipe services into turbine hall

Products:

Epo-chem RS 500P™ a wet and surface tolerant mio epoxy primer and Epo-chem™ RA 500 series, a moisture tolerant glass flake filled epoxy top coat, providing excellent long term corrosion resistance.

Environment:

15°C – 60°C sea water

Challenge:

The original coating specification was considered as an atmospheric environment, upon inspection it was found that regular leaks changed the structural steel exposure to immersed causing the original paint systems to fail.

Budget restrictions, access difficulties and age were all a consideration. No abrasive blasting was possible as the costs would’ve been prohibitive with containment and clean up.

Chemco’s Solution:

• Reclassify from atmospheric exposure to immersed due to the regular salt water leaks.
• High pressure water blast up to 20,000 psi using our small foot print machine after mechanical clean in the difficult to reach areas.
• Application of Epo-chem™ RS 500P to a nominal thickness of 100µm and top coat using Epo- chem™ RA 500 with a nominal DFT of 350µm

Results:

Saved hundreds of thousands of dollars in replacement costs and the asset owner is rest-assured that Chemco will provide long term corrosion protection, evident through the years of applications around the power station.

Industry:                      

Power Generation,

Date:

March 2003,

Substrate:

Cast Iron,

Products:

Chem-tect™ RB 332, glass flake filled vinyl ester,

RC 200 Anti Foul, copper pigmented polyester resin & Externals with RL 500PF a surface/wet tolerant zinc rich epoxy.

Environment:

Sea Water,

Challenge:

Our clients strainer has been in service for 30 years. Upon inspection of the strainer body, back wash covers & critical dimensions found the substrate to be severely corroded, illustrated by the extent of graphitised cast iron, holes through the casting and diminishing wall thickness.

Chemco’s Solution:

Pre-abrasive blast and machine datum points to ensure reference points remain for post machining, sealing ring & shaft lands. Needle gun/scabble graphitised material prior to Hot Wash and abrasive blast cycle to reduce soluble salts to an acceptable level.

Scope:

• Mask up critical dimensions.
• Abrasive blast to AS 1627.4 Class 3
• Application of RB 332 to the internals including flange, rebates and shaft landing areas.
• Reinforce casting using Composite repair techniques to reinstate original strength.
• External coating application to System A which includes the application of RL 500PF @ 300um
• Application of RC 500GTC Jade Green
• Packaging and protection for transport

Results:

Refurbishing the Hicks Hargraves Strainer saved the company up to $150,000. RB 332 will provide long term protection coupled with the non-toxic anti-foul coating will prevent marine growth for a minimum of 5 years.

Industry:                      

Mining and Mineral Processing,

Date:

April 2010,

Substrate: 

Steel multi-stage pump casing, galvanised coupling,

Products:

Epo-chem™ RL 500PF,

Epo-chem™ RW 500 – Solvent Free Novolac Epoxy,

Environment:                

80°C corrosive aqueous ammonia,

Challenge:

The client required an external coating system to provide long term protection to their newly purchased multi-stage pump assemblies against an aqueous ammonia environment at elevated temperatures. The coating system was required to act as a corrosion barrier for the pump case should any leaks occur whilst in service. Abrasive blasting could not be deployed due to the risk of damaging critical components.

Chemco’s Solution:

We recommended RL 500PF which primes and finishes in 1 coat. This coating system requires minimal surface preparation. It is moisture/surface tolerant coating is ideal for site maintenance contracts. Rain or high humidity has no effect on painted surfaces.

We followed this with RW 500, a solvent-free epoxy Novolac which imparts outstanding protection to metal substrates. It forms a durable barrier resistant to abrasion, erosion, thermal shock, and the most aggressive environments of high temperature and chemicals in immersed and non-immersed conditions.

Scope:                          

• Mask off seal areas, ID plates and critical exposed fittings. Mechanically prep surface, solvent wash with MEK
• Prime with 1 coat RL 500PF to prepared surfaces
• Apply2 coats RW 500 to a DFT of 400µm
• DFT checks, mount onto base frame, assemble coupling guard

Results:

The two product systems applied by skilled applicators resolved the no abrasive blasting issue and currently provides durable protection against a high temperature corrosive aggressive environment.

Industry:

Marine – Shipping

Date:

April 2001

Substrate:

Cast iron sea chest

Products:

Chem-tect™ RB 300 Series – Glass Flake filled vinyl ester resin
RC 200 Antifoul

Environment:

Sea Water

Challenge:

The internals of a sea chest located in the engine room were heavily corroded and required refurbishment. This included encapsulation and effective dust extraction to prevent mechanical damage inside the engine room. Work had to be completed within 20 hours to prevent disruption to existing schedule.

Chemcote’s Solution:

We recommended the use of RB 300 series @ 1200μm nominal thickness.  The top coatapplied contains a non-toxic anti-foul. Applied @ 300μm it will provide excellent protection against salt corrosion

Scope:

• Pre-abrasive blast to remove graphitised metal
• Hot pressure wash and re-grit blast to ISO 8501-1 cleanliness standard with a minimum 75µm profile
• Application of 3 coats of RB 300 series providing peace of mind for at least the next 10 years
• Application of Copper based epoxy in two coats to prevent marine growth

Results:

With Chemco Australia’s successful application, many other components have been refurbished using similar methods. This can be done both on board, and within our fully equipped workshop located in Wollongong.

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Industry:                      

Chemical Manufacturing

Date:

2010

Substrate:

Steel Substrate

Products:

Chemco Epo-chem™ RS 500P (Moisture & Surface Tolerant)

Chemco Epo-chem™ RA 500M (Wet Tolerant)

Environment:

Ammonia Pipeline externals

Challenge:

The ammonia lines had been in service since the plant was built. This has caused severe external corrosion caused holes to form in the pipe and there were no spare lines for the plant to be shutdown. Very expensive pipe sealing clamps were in use and the condition of the rest of the pipelines were deteriorating rapidly as the pipes are constantly cold and very wet. Engineers had put corrosion protection of the pipes in abeyance which was just exacerbating the problem.

Before – Ammonia bullet pipelines

Surface Prep – 20,000 psi Water Blasting

Glass flake filled epoxy corrosion barrier applied

Top coat colour applied

Chemco’s Solution:

Moisture-Tolerant and Solvent-Free epoxies RS 500P and RA 500M were recommended as this system requires minimum surface preparation (i.e. no dry grit blasting) and solvent-based materials were not allowed. These epoxies are ideal for confined spaces.

Rain, water, condensation or high humidity has no effect on freshly painted surfaces and its environmentally friendly properties allowed work to continue throughout the Queensland Wet Season. Areas were high-pressure washed at 500bar to a WJ4 standard. Coating was applied to an average DFT of 300µm.

Results:

This coating system is relatively new to Australia and is a prime example of innovative technology being used to save the existing plant from the possibility of catastrophic failure. Despite the extreme weather experienced in Queensland and the complex layout, the coating work was finished on time and within budget. As a result, there will be considerable savings in the cost of pipe sealing clamps in the future and improvement in plant safety has exceeded the engineer’s expectations.

Industry:                     

Steel Manufacturing

Date:

November 2014

Substrate:

Internals of small diameter pipe.

Products:

Chemco International – InD-cote™

Top coat using RP 500 AR  

Environment:

Abrasive Coke Breeze temperatures up to 60ºC.

Challenge:

Existing pipe lasts 4 weeks in service before a hole appears and valves an estimated 18 months service.

Chemco’s Solution:

A new addition to the Chemco International range, illustrating further coating advancements based on research and development, we now have InD-cote™; a Ceramic Bead Filled High Temperature epoxy, designed to provide protection to aggressive sliding abrasion applications, reinforced with a wrap of woven basalt fibre  and top coated with RP 500 AR.

Scope:

• Machine rebate on flanges.
• Abrasive blast to AS 1627.4 as per Chemco requirements.
• Application of InD-cote™ and top coat using RP 500AR.
• Application of Basalt Fibre wrap using RP 500 AR Series
• Machine coated rebates

Results:

Based on the success of previous applications with a combination of our Abrasion Resistant composite systems using basalt fibre in abrasive environments a solution was sought after using the Chemco range of products and expertise. After regularly replacing these sections of pipe on a monthly basis the plant maintenance team are very happy with 9 months of service and still going. Stay tuned by sending us an email if you want to find out more.

Industry:                          

Co-generation & Gas

Date:

November 2010

Substrate:

Mild Steel

Products:

Epo-chem™ RL 500PF – Surface and moisture tolerant zinc rich epoxy

Environment:                  

Methane gas co-generation plant exhaust stack trials.

Challenge:

15 year old plant was showing signs of premature corrosion within 3-4 years of commissioning. Spark free surface preparation was a strict requirement. Plant outage was not possible and work was required to proceed whilst online with an estimated 105°C on the surface.

Chemco’s Solution:

Chemco’s application of wet & surface tolerant coatings was carried out with minimal disruption to the everyday activities with an expected life in excess of 10 years before any signs of corrosion are visible.

Scope:                       

Mobilize to site and work in with plant maintenance personnel to ensure all risks are assessed and reduced where possible. Obtain safe access and mechanically clean, using a wire brush only. Application of 2 coats of RL 500PF with a nominal DFT of 300µm.

Results:

Many other coatings were trialled and failed within a 3 month period. The site has been revisited many times over the past 5 years with no signs of coating failure. Plant Maintenance Engineers are pleased with the results and look forward to solving other corrosion issues.

Industry:                     

Water Treatment

Date:

2009

Substrate:

304 Stainless Steel

Products:

Chem-tect™ RB 300 series

Epo-chem™ RL 500PF

Environment:

Seawater/chlorinated – treatment water

Challenge:

Short time frame requiring quick turnaround. Customer required provision of long term corrosion protection.

Chemco’s Solution:

Working around the clock and the application of proven RB 300 series, a glass flake filled vinyl ester with excellent resistance to chemical and abrasive protection.

Scope:

Grind welds and sharp edges. Machine rebate to all flange faces to prevent crevice corrosion caused by misaligned gaskets.

Abrasive blast to Class 3 AS 1627.4 75micron profile (nominal) Apply of 2 coats of RB 300 Series to a DFT (dry film thickness) of 1200 microns.

Carry out QA including holiday test @ 8kV and confirm thickness.

Externals protected with 1 coat of RL 500PF

Results:

Extremely fast turnaround and cure time – back in production in 3 days. Expected to exceed life requirement of 25 years, plus reduce maintenance cost in the future.

Industry:                      

Steel Manufacturing

Date:

January 2015

Substrate:

Mild steel substrate

Products:

Epo-chem™ RE 500P & RW 500

Environment:

1,000°C Coking Coal transport wagon and moved to the quenching station, where 80°C recirculated water is used.

Challenge:

Major structural steel repairs are carried out every two years due to the aggressive nature of this environment, the regular thermo cycling in service exceeds many coatings limitations. Oven temperature Coke is pushed in the Hot Car wagon where all of the coated surfaces are protected with sacrificial wear plates acting as heat shields where it is transported to the quenching area and an estimated 80 tonnes of recirculated water is dumped onto the Hot Coking Coal.

Engineers have tried and tested many different coatings with varied results. Main challenges are most of the work is carried out on site where abrasive blasting is not always possible due to the tight time schedule whilst other trades are working alongside the Chemco Applications Team.

Chemco’s Solution:     

We recommended Epo-chem™ RE 500P a high temperature resistant surface tolerant, Novolac Epoxy primer. Top coated with Epo-chem™ RW 500, glassflake filled, high temperature resistant Novolac Epoxy. The coating system provides excellent corrosion/erosion resistance against this environment.

Scope:                         

Abrasive blasting to AS 1627.4 Class 3, 60µm profile on new sections in our workshop.

All areas on site were mechanically cleaned using a scabbler, needle gun and bristle blaster to thoroughly remove all signs of corrosion. Application of RE 500P in one coat at 100µm nominal and application of RW 500 at 350µm Dry Film Thickness (DFT).

Results:

Most linings were failing within a short period of time, between 2 & 8 weeks of service. An inspection of Chemco Internationals high temperature coating systems after 2 weeks has indicated the lining is in excellent condition.

Industry:                           

Petrochemical – Oil Refinery,

Date:

2002,

Substrate:

Mild Steel water boxes & bronze tube sheets,

Products:

Chem-tect™ RB 300 series,

Environment:

60-80°C, re-circulated & sea water,

Challenge:

Tube sheets of this chiller were severely corroded due to a galvanic reaction between dissimilar metals. A 72 hour shutdown period was utilised to complete the work. The tube internals had to be protected from abrasive blasting damage. There was also severe pitting corrosion on sealing faces.

Chemco’s Solution:

Tube internals were protected by inserting specially designed plastic caps.

The entire chiller face was abrasive blasted to ensure surface is clean and free of contamination. RB 300 was applied to tube-sheet face, followed by post machine sealing faces to ensure division plates mate, preventing interference and by-passing. Caps were removed. Chemco also supplied nylon inserts to prevent tube end corrosion & cavitation.

Results:

This client has become one of our regular customers. Chemco Australia has now conducted numerous jobs for this client over the past years, including multiple heat exchanger units. The photo to the left was taken during a 4 year inspection of another chiller unit coated with the same coating and showed no signs of deterioration.

Industry:                          

Oil & Gas,

Date:

April 2009,

Substrate: 

Structural Steel,

Products:

Epo-chem™ RS 500P,

Epo-chem™ RA 500M,

Environment:                  

Hot and humid, sea mist,

Challenge:

Highly corroded carbon steel decks would have taken 12 months to re-surface with riding crew permanently on board. Corrosion would have re-appeared upon completion under high humidity and rain conditions.

Chemco’s Solution:

Chemco’s application of wet & surface tolerant coatings was carried out with minimal disruption to the everyday activities and came with a 10 year warranty, much to the rig manager and asset owner’s satisfaction.

Scope:                       

15,000 – 19,000 psi water blast with small footprint machine

Wet abrasive blasting to reduce metallic salt content

Perforations were found in accommodation quarters and other critical areas

Applied 1 coat RS 500P and laminated using 600gm/m2 multi-directional matting

Applied 1 coat RA 500M with a nominal thickness of 500μm—700μm

Results:

Application was complete within client’s time frame, and asset owner also saved 12 months of downtime and repetitive painting costs. Chemco Australia has been awarded continuous work on the rest of the problem areas and other rigs from the same client.

Industry:                        

HVAC, Power Generation, Oil & Gas,

Date:

February 2012,

Substrate: 

Cast Iron,

Products:

Epo-chem™ RS 500P,

Epo-chem™ RA 532,

Environment:                

Recirculated water,

Challenge:

This heat exchanger vessel was manufactured in 1981 and installed shortly after. Fatigue cracking was found in some welds and localised corrosion was discovered on the tube bundle guides. The unit was exposed to inclement weather.

Chemco’s Solution:

We recommended coating with our moisture and surface tolerant epoxy RS 500P as a primer. Finishing with a top coat of RA 532, a glass-flake filled epoxy solvent-free system. This protective coating system will with provide long term protection in this environment.

Scope:                           

• Identify damaged areas and check existing specification thickness
• Bristle blast damaged surface area
• Solvent wipe and square off using masking tape
• Application of RS 500P in one coat to a nominal DFT of 100µm
• Application of RA 532 in one coat to a minimum DFT of 250µm

Results:         

Chemco was able to carry out the repairs to the internals of the heat exchanger vessel within the strict time frame provided by the client. This application will provide at least 10 years of corrosion free service.

Industry:           

HVAC,

Date:

March 2006,

Substrate:

Admiralty bronze 200/200,

Products:

Chem-tect™ RB 300 – Glassflake filled vinyl ester,

Ceram-chem™ RP 500 – Ceramic filled epoxy designed to improve lumber flow,

Environment:

Ambient Sea Water,

Challenge:

Original pumps were suffering severe corrosion and cavitation.

Chemco Australia’s Solution: 

We recommended the use of RB 300 series @ 1200μm nominal thickness and top coat with 2 coats of RP 500 @ 300μm.

Scope:

• Pre machine critical dimensions
• Abrasive blast to ISO 8501-1 cleanliness standard with a minimum 75μm profile.
• Mask and protect all area not to be coated
• Application of 2 coats of RB 300 series
• Application of RP 500 in two coats to improve fluid efficiency
• Post machine to allow re-assembly
• Balance impeller as required

Results:

Some engineering changes were made to the strainer system prior to the installation of these 3 pumps. Coupled with our coating system, these pumps can now expect long term protection – with minimal maintenance. Tube sheets, pipe-work and many other components have been protected using similar methods both on site and within our fully equipped workshop located in Wollongong.

Industry:

Oil & Gas Industry,

Date:

April 2010,

Substrate:

Carbon Steel Rig Decks,

Products:

Epo-chem RS 500P

Chem-tect RA 500M

Environment:

Wet & Humid, atmospheric moisture 

Challenge:

Heavily corroded steel rig decks would have taken 12 months to re-surface with riding crew permanently on board. Corrosion would have re-appeared upon completion due to high humidity and rain conditions.

The Rig                Ultra high water blasting           One section completed

Chemco’s Solution:

Chemco Australia recommended the use of moisture surface tolerant glass-flake filled epoxies, applicable to wet and corroded surfaces providing long term corrosion protection.

Scope:

• 15,000-19,000 psi water blast with small footprint machine
• Wet abrasive blasting to reduce metallic salt content
• Perforations were found in accommodation quarters and other critical areas
• Applied 1 coat RS 500P and laminate using 600gm/m2 multi-directional matting
• Applied 1 coat RA 500M with a nominal thickness of 500μm-700μm

Results:

Application was done within client’s time-frame and also came with a 10 year warranty, much to the rig manager and asset owner’s satisfaction. Asset owner saved 12 months of downtime and re-coating costs. An estimated 20,000 m² of rig deck has been coated to date. Chemco Australia has also been awarded continuous work on the rest of the problem areas and other rigs from the same client.

Industry:

Power Generation,

Date:

Aug 2012,

Substrate:

Cast Iron,

Products:

Chem-tect RB 300 Series – Glass flake filled vinyl ester resin

Chem-glass RC 200 Anti foul – Copper pigment based polyester resin

Environment:

Ambient Salt Water,

Challenge:

To extend the operating life of heavily corroded, 30 year old suction tubes, the 15-20mm deep pitting requires pit filling and reinforcement using composites.

Corroded tube              Internals repaired           Suction tube completed

Chemco’s Solution:

We recommended the application of RB 308 to fill deep pitting by extensive trowelling. Intermediate coat using RB 332 and top coat using RP 500, a ceramic filled epoxy designed to provide improved efficiency and reduced growth.

Scope:

• UHPWB at 20,000psi to remove graphitised material and abrasive blast cycle to reach <25ppm chloride levels.
• Abrasive blast to AS1627.4 Sa2.5 with a nominal surface profile of 75µm.
• Application of RB 300 primer in one coat.
• Application of RB 308 to fill pits and RB 332 to ensure smooth internals.
• Carry out QA to ensure no holidays exist, repair where required.
• Top coat, 2 coats of RP 500
• External coating system is repeated, except for the topcoat where RC 200 antifoul is applied to prevent marine growth.

Results:

Pump efficiency has improved with the additional protection of the complete Chemco coating system. In addition Chemco has managed to reduce downtime and save thousands of dollars in replacement costs.

Industry:

HVAC,

Date:

March 2006,

Substrate:

Admiralty bronze 200/200,

Products:

• Chem-tect RB 300
• Ceram-chem RP 500

Environment:

Ambient Sea Water,

Challenge:

The original sea water volute pumps were suffering severe corrosion and cavitation. The pumps would require refurbishing and machining to original profile.

Volute after blasting      Impeller eye coated     External coating completed

Chemco’s Solution:

We recommended the use of RB 300 series @ 1200μm nominal thickness and top coat with 2 coats of RP 500 @ 300μm

Scope:

• Pre machine critical dimensions
• Abrasive blast to ISO 8501-1 cleanliness standard with a minimum 75μm profile.
• Mask and protect all area not to be coated
• Application of 2 coats of RB 300 series
• Application of RP 500 in two coats to improve fluid efficiency
• Post machine to allow re-assembly
• Balance impeller as required

Results:

Some engineering changes were made to the strainer system prior to the installation of these three sea water volute pumps. Coupled with our coating system, these pumps can now expect long term protection -with minimal maintenance. Tube sheets, pipe-work and many other components have been protected using similar methods both on site and within our fully equipped workshop located in Wollongong.

Industry:

Power Generation,

Date:

November 2001,

Substrate:

10 year old carbon steel Intercooler Vessel,

Products:

Chem-tect™ RF 300P,

Chem-tect™ RF 332,

Epo-chem™ RL 500PF

Environment:

High Pressure Steam, exceeding 150°C,

Challenge:

The vessel was experiencing severe corrosion and metal loss. We had a short window to machine rebates in all flange faces to allow coating to be applied from the internals out onto the flange face.

Vessels on arrival              External coating              Internal lining

Chemco’s Solution:

On close inspection, deep pitting was found in a number of areas, particularly in the bottom part of the vessel. Weld repairs would have delayed the project so Chemco recommended pit-filling to be carried out to reduce down time and the use of composite fibres to increase strength. RF 300 series was recommended as the coating requires low maintenance and ease of repair-ability. It will also provide 20 years of corrosion protection.

Scope:

• Abrasive blast to AS 1627.4 2005 75
• Reduce metallic salts using 90°C high pressure water. Re-abrasive blast to above standard.
• Application of 1200µm of RF 332: A glass flake filled high temperature vinyl ester designed to provide long life corrosion protection.
• All internal and external flange faces are coated to ensure full protection.
• High Voltage spark test @ 8kV DC & rectify defects
• Application of RL 500PF in two coat and RC 500GTC.

Results:

The intercooler vessel was inspected 4 years and again 8 years after original application and found in excellent condition. There were no signs of corrosion or coating breakdown. Some mechanical damage to the internal lining required repairs where the tube bundle installation/inspection impacted on the lining integrity on the guides.

Industry:

Oil & Gas Industry,

Date:

March 2008,

Substrate:

Lining on produced water treatment vessel,

Products:

Epo-chem™ RW 564,

Environment:

Produced water environment (coalescing) at 95°C,

Challenge:

The original coating was failing with osmosis blistering and exposure of the substrate to the cargo which caused localised corrosion pitting. Remedial work for this job needed to be completed along side ongoing repairs to ensure that the vessel arrived in Singapore in 2 years time for a refit. Corrosion rates of 2-3 mm per year would have reduced vessel’s corrosion allowance to zero resulting in a vessel perforation.

Removing original coat      Pinholes                Completed internals

Chemco’s Solution:

Chemco Australia recommended that the affected areas be abrasive blasted and treated with repeated high pressure hot washes. A steam lance would heat the vessel up with steam to 400°C to remove salt from the pin-holes. Measurement of pinholes would ensure glass-flake epoxy coating filling. During the application of the coatings, metallic salt, environment and high voltage spark testing would be carried out to guarantee long life protection.

Scope:

• Abrasive blasting to remove coating
• Salt tests revealed metallic salts, contaminated areas
• After water washing and drying, abrasive blast to whip surface back to class 2.5.
• Spigots were blasted using angle nozzle
• Whip blasting of floor and spigots for salt test
• Area carefully hand painted to fill pinholes
• Coating inspected and declared fit for purpose
• Vessel boxed and pressure tested

Results:

Pinholes affected the ‘wash area’ in an 800‐1000mm wide band below the tank’s centerline. Osmosis blistering resulted in crevice corrosion which was invisible at the coating application stage. These pin-holes measured 3-4 mm in depth and .5-1mm wide. Previous coating failure had developed a concentration cell with a difference in aeration, depleted of oxygen, which led to a highly corrosive condition in deepening the pinhole.

The vessel’s internal lining was replaced with corrosion resistant glass-flake filled epoxy resin. This film will protect the substrate and prevent further metal loss. The Chemco team carried out the job successfully despite many challenges and maintained final coating quality much to client’s satisfaction. The pin-holing challenge was resolved by pit-filling and is to be reviewed in future NFT programs.

Industry:

Petrochemical – Oil Refinery,

Date:

2002,

Substrate:

Mild Steel water boxes & bronze tube sheets,

Products:

Chem-tect™ RB 300 series,

Environment:

Ambient sea water inlet side and 60-80°C outlet side.

Challenge:

The cooling water system was severely corroded and required refurbishment. The tube sheets were corroded due to a galvanic reaction between dissimilar metals. A 72 hour shut down period was utilised to complete the work. The tube internals required protection from abrasive blasting damage. Sealing faces were suffering severe pitting corrosion also.

Tubesheet on arrival         On completion            Condenser water boxes

Chemco’s Solution:

Tube internals were protected by inserting rubber bungs from internal damage the surface treatment process.

The entire face was abrasive blasted to ensure surface is clean and free of contamination. RB 300 was applied to tube-sheet face, followed by post machine sealing faces to ensure division plates mate, preventing interference and by-passing. Caps were removed.  Chemco also supplied nylon inserts to prevent tube end corrosion & cavitation.

Results:

This client has become one of our regular customers. Chemco Australia has conducted numerous jobs for this client over the years, including multiple heat exchanger and condenser units. During a routine 4 year inspection, other cooling water systems coated with the same coating which showed no signs of deterioration.

Industry:

Civil,

Date:

October 2014,

Substrate:

40-50 Year Old Pillar Steel Reinforcement,

Product:

Epo-Chem™ RS 500P,

Environment:

Basement of Cold Press Mill,

Challenge:

The challenge was to refurbish heavily corroded steel reinforcement within concrete pillars and to protect against future corrosion attack. The application of corrosion protection needed to be carried out in a high humidity environment and onto the wet surface of the steel.

Exposed reinforcement      Neutralising pH            Ready for concreting

Chemco’s Solution:

Chemco proposed to gain access to steel reinforcement requiring corrosion protection by physically removing the deteriorated concrete. The steel reinforcement required pH neutralising using an Alkaline cleaner solution. The concrete reinforcement would then be protected against corrosion with an application of RS 500P onto the wet steel surfaces.

Scope:

• Jack pick/hammer all deteriorated concrete.
• Ensure reasonable access to all affected areas of reinforcement.
• Application of rust converter allowing it to sit overnight.
• Neutralise pH of steel surface.
• Application of RS 500P.

Results:

Work on the concrete reinforcement was carried out within a tight time frame allowing civil contractors to return to build form-work and encapsulate with concrete. The ease of application of RS 500P onto wet substrates together with its corrosion protection properties makes this coating ideal for structures in this environment.

Industry:

Power Generation,

Date:

August 2002,

Substrate:

10 year old carbon steel vessel,

Products:

Chem-tect™ RB 300P & RB 332 ,

Environment:

Demineralised water,

Challenge:

The vessel was originally rubber lined. Osmotic blistering found during an inspection raised concerns about metal loss due to the loss of lining integrity. Over the years the rubber lining had been patched & repaired to the point it was no longer serviceable. The vessel would take 2 weeks to replace. Chemco recommended an alternative solution which was faster and less disruptive.

Osmotic blistering         Coating completed      Re installation of lateral pipe

Chemco’s Solution:

On close inspection, deep pitting was found beneath the rubber lining. Weld repairs would have delayed the project so Chemco recommended pit-filling to be carried out to reduce down time. The RB 300 series was recommended as the coating requires low maintenance and ease of repair-ability. It will also provide 20 years of corrosion protection.

The entire project was carried out on site over a period of 36 hours allowing a fast return to service with minimum disruption to production. The vessel was ready for use 12 hours after completion.

Scope:

• Remove rubber lining.
• Abrasive blast to AS 1627.4 2005 75
• Reduce metallic salts using 90°C high pressure water.
• Application of 1200µm of RB 332: A glass flake filled vinyl ester designed to provide long life corrosion protection.
• All internal and external flange faces are coated to ensure full protection.
• High Voltage spark test @ 15kV DC & rectify defects
• Re-installation of the lateral pipe work.

Results:

The cation vessel was inspected 18 months and 5 years after original application and found in excellent condition. There were no signs of corrosion or coating breakdown.

Industry:

Oil Refinery,

Date:

2007,

Substrate:

Steel floor with failed coating,

Products:

Epo-Chem™ RA 500 series,

Environment:

Immersed, ambient, possible MIC,

Challenge:

This petrochemical client had 40m diameter fuel oil storage tank with floor and 2m wall which required re-coating. The coating system requirement was for one which offers a long term corrosion solution that will provide in excess of 15 years of service. Time-constraint as the tanks had to return to service as soon as possible.

 Coating of oil storage tank floor and walls completed

Chemco’s Solution:

We recommended coating with Chemco RA 564, a glass-flake reinforced epoxy resin system that can provide long term corrosion protection in the storage tank for more than 15 years. This coating also provided extremely fast turnaround and cure time, the oil storage tank could be returned to production quickly. The coatings moisture tolerance meant there was no requirement for de-humidification, hence cost is reduced and no delays with weather.

Scope:

• Abrasive blast to Class 2.5 AS1627.4,
• Application of 2 coats of RA 564 to a DFT of 100 microns

Results:

This solvent free, no odour, no VOC coating solution also meant there were reduced OHS concerns, and no impact on the environment and no restrictions with surrounding trades. The coating’s long term protection also meant the client’s future maintenance costs have been reduced dramatically.

Industry:

Water Utilities,

Date:

August 2004,

Substrate:

Cast iron body,

Products:

Chem-tect™ RB 332,

Chem-tect™ RB 300GL,

Environment:

Dam Water,

Challenge:

The client’s pump had dropped off in efficiency. This was due to the combination of corrosion and mechanical fatigue. The client was looking to improve efficiency and reduce power consumption.

After abrasive blast      Internal Coating Completed    Re-assembly

Chemco’s Solution:

After 25+ years in service the substrate was heavily contaminated with metallic salts. This required heat treatment and a number of abrasive blasts to reduce salts below 25ppm.  We then recommended the application of 2 coats of RB 332; a glass flake filled vinyl ester providing an excellent corrosion barrier and long term protection. We then applied 2 coats of RB 300GL to enhance fluid efficiency in turn reducing power consumption.

Scope:

• Strip and assess
• Manufacture template to ensure mating faces match
• Grind rebates on all flanged faces, allowing the coating to be applied on the flange face preventing future crevice corrosion.
• Protect critical dimensions
• Abrasive blast and treat to reduce metallic salts by hot washing and re-abrasive blast.
• Apply corrosion barrier RB 332
• QA included spark testing
• Rebuild gland packing areas
• Apply top coat of RB 300GL

Results:

Pump repairs were achieved and by coating with RB 300, future corrosion is prevented with a reduced amount of friction through composite technology. The pump now functions more efficiently when in use and consumes less power, which led to carbon credits and greenhouse gas reduction. The payback period of the entire refurbishment worked out to be only 14 months.

Industry:

Power Generation,

Date:

2002,

Substrate:

Mild Steel water boxes & mild steel tube sheet with a copper alloy combination tube,

Products:

Chem-tect™ RB 300 series,

Environment:

60-80°C, sea water,

Challenge:

Tube sheets were corroded due to a galvanic reaction between dissimilar metals. These were treated on site by scaffolding and encapsulation to prevent dust in the station. A two week outage allowed time for removal of the condenser water box units from site, fabrication repairs to corroded areas and machining of rebates prior to deliver to our workshop. There was a large amount of work to be completed within a tight time frame.

Condenser water boxes in the workshop

Chemco’s Solution:

• Work commenced on a round the clock basis, an understanding of the required deadline
• Abrasive Blast to AS 1627
• Application of primer to all surfaces
• Pitfill all corroded areas and reinforce using composite materials i.e. fibreglass
• Application of RB 332 in 3 coats
• Carry out QA to ensure coating longevity
• Application of RC 500 to prevent marine growth

Results:

This client has become one of our regular customers particularly for its cooling water systems. Chemco Australia has now conducted numerous jobs for this client, including multiple condenser water box units. During a routine inspection, it was noted that another unit with the same coating showed no signs of deterioration.

Industry:

Oil & Gas, Marine,

Date:

November 2005,

Substrate:

Cast iron Valve body,

Products:

Chem-tect™ RB 300 Series – Internals

Epo-chem™ RL 500PF – Externals

Environment:

Sea water,

Challenge:

The internals of the valve were heavily graphitised requiring refurbishment as a replacement would have taken up to 12 weeks because this is an imperial non-standard item. Guide channel for the valve was entirely corroded away. Coating and refurbishment had to be completed within 120 hours to prevent disruption to existing shutdown schedule.

Corroded valve body  Coating on flanges Coating completed & valve installed

Chemco’s Solution:

Chemco Australia recommended RB 300 at 1200μm nominal thickness, a glass-flake filled vinyl ester which provides a tough impermeable barrier that will last in excess of 10 years. Externals finished with top-coat RL 500PF, a moisture and surface tolerant coating.

Scope:

• Protect critical sealing faces
• Abrasive blast to remove graphitised metal
• Grind rebates on flange faces to allow coating to wrap around preventing crevice corrosion due to misaligned gaskets.
• Remove graphitised material with air chisel
• Hot pressure wash – re-grit blast to AS 1627.4 cleanliness standard with a minimum 75μm profile
• Application of 3 coats of RB 300
• Install nylon bars to replace corroded guide
• Test valve operation
• External application of RL 500PF in 2 coats

Results:

The valve was refurbished, saving the client replacement costs and waiting time.  The client was extremely satisfied with this job and have since awarded other items to be refurbished by Chemco using similar methods.

Industry:

Power Generation,

Date:

2009,

Substrate:

Steel with failed concrete lining,

Products:

Chem-tect™ RB 300 series,

Epo-chem™ RL 500PF,

RC 500 GTC top coat,

Environment:

Sea Water,

Challenge:

A short time frame requiring quick turnaround. Pipe spools required long term corrosion protection.

Convoluted Pipe            Rebated flange          Copper based coated pipes

Chemco’s Solution:

Working around the clock, preparing surfaces and coating pipe spools with RB 300 series, a robust glass flake filled vinyl ester and top coating with a non toxic anti foul copper based epoxy preventing marine growth.

Scope:

• Grind welds and sharp edges.
• Grind rebate to all flange faces to prevent crevice corrosion caused by misaligned gaskets.
• Abrasive blast to Class 3 AS 1627.4 75 micron profile (nominal)
• Apply of 2 coats of RB 300 to a DFT of 1200 microns and 1 coat polymer copper.
• Carry out QA including holiday test @ 8kV and confirm thickness.
• Externals protected with 2 coats of RL 500PF and topcoat PU

Results:

An extremely fast turnaround and cure time meant that the pipe spool was back in production quickly (in this case, 3 days). With Chemco’s protective coatings, the pipe is expected to exceed life requirement of 25 years as well as reduce maintenance cost in the future. No fouling of internals from marine growth for many years to come.

Industry:

Power Generation,

Date:

May 2010,

Substrate:

Salt Water Strainer,

Products:

Chem-tect™ RB 332,

RC 200 Anti Foul

RL 500PF,

Environment:

Sea Water,

Challenge:

Inspection of the strainer found there to be a large amount of external corrosion and severe localised pitting on the internals, particularly around the sealing ring.

Externals on arrival   Rebuilt sealing land   Completed strainer

Chemco’s Solution:

Due to the amount of metallic salts found after the preliminary abrasive blast it was necessary to hot wash the strainer components in an attempt to lower the salt content. Re-abrasive blasting was carried out and composite materials were chosen to rebuild the metal loss found on the tube plate support ring. Rebuilding this metal loss using our reinforced glass technique. Chemco ensured the tube plate had a flat area to rest on the mounting/sealing ring, in turn reducing costs and the additional time involved with machining.

Scope:

• Abrasive blasting to Chemco standards
• Application of RB 332 to the internals including the rebates
• External coating application to System A which includes the application of RL 500PF @ 300um
• Application of RC 500GTC Jade Green
• Packaging and protection for transport

Results:

Strainer was completed in time for re-assembly. RB 332 will provide long term protection coupled with the non-toxic anti-foul coating will prevent marine growth for a minimum of 5 years.

Industry:

Power Transmission,

Date:

2002 to 2010,

Substrate:

Galvanised Steel,

Products:

Chem-tect™ RB 300,

Environment:

Atmospheric –buried low or high pH soil depending on location,

Challenge:

Metal loss was detected on some legs of the transmission towers while other legs showed signs of severe corrosion at the highly susceptible natural air/ground interface of the steel members.

The client needed help in strengthening the legs of the affected transmission towers and was looking for a solution that would last 50 years. This was highlighted as a necessity for the towers that are in areas exposed to varying pH level soil & prone to poor water drainage and flooding.

Metal loss detected    Splicing corroded members    After coating

Chemco’s Solution:

We recommended coating with RB 300, a glass-flake filled vinyl ester, which has excellent resistance to corrosive environments. It provides a tough impermeable barrier suitable for steel and concrete surfaces. This system, once applied, can prevent future corrosion on the steel legs of the transmission towers for the next 50 years.

Scope:

• Excavate and break out foundation, removal of earthing strap if required.
• Install wire rope sling on transverse face according to wind direction, rope tension – 3.5kN, min SWL – 23kN
• Remove tower bolts and clamp reinforced angle steel inside existing leg, match drilling process
• Holes sprayed with Cold Gal & high tensile bolts used
• Punched bolts so that nuts don’t come loose
• Abrasive blast & apply RB 332 as per specification.
• K-brace strengthening
• Polymer concrete independently tested and rated up to 65 MPa (NATA certification)
• Non-shrink to prevent gap between concrete and steel surfaces

Results:

The customer was most satisfied with the outcome. Chemco Australia has been awarded subsequent jobs due to the success of these repairs.

Industry:

Petrochemical,

Date:

Mar 2011,

Substrate:

Floating heads and channel end covers cast from various exotic materials,

Products:

Chem-tect™ RB 332,
Epo-chem™ RL 500PF,

Environment:

Salt water at elevated temperature,

Challenge:

The end covers were originally coated by another contractor with varying results. Some items were made from exotic materials and had minor pitting along the sealing face and localised areas.

End cover pitted & corroded    Sealing face built up         Rebates filled

Chemco’s Solution:

To prevent long term corrosion by applying RB 332 to the internals of the end covers. Sealing areas showing signs of corrosion pitting were pre-machined to allow for 1mm of coating to be applied and post machined on completion.

Scope:

• High pressure washed internal & externals
• Inspection of damaged/heat affected areas
• Abrasive blasting to better inspect man hole cover
• Pitfill application of RB 332 series in 2 coats
• Thickness tested to ensure a minimum of 750µm and holiday test at 6Kv
• Externals: Application of 2 coats of RL 500PF to a nominal thickness of 300µm
• Application of 2 coats of N35 Luxathane R

Results:

Chemco delivered a fast turnaround, reducing down-time for the client in the short term and delivering the end covers with expected long term corrosion protection.

Industry:

Water Treatment,

Date:

2013,

Substrate:

Mild Steel Structure,

Products:

Epo-chem™ RS 500P –Wet & Rust tolerant 100% solids epoxy,

Epo-chem™ RA 500 – Wet & Rust tolerant glass flake filled 100% solids epoxy,

Environment:

Waste Water Effluent – pH 9,

Challenge:

To provide a cost effective coating system offering a long-term anti-corrosion solution that will ensure in excess of 15 years’ service life for an aerobic reactor.

Plant in operation             Corroded Floor              Application of top coat

Chemco’s Solution:

We recommended priming with RS 500P, followed by RA 500 top coat.

Scope:

• Abrasive blast to AS 1627.4 with a nominal 50-75µm profile.
• Application of 1 coat of RS 500P with a nominal DFT of 60-100µm.
• Check film thickness in a grid pattern (between coats)
• Strip coat using RA 500 Series on all welds and changes in direction to ensure coverage.
• Application of 1 coat of RA 500 Series with a nominal total DFT of 300µm.
• Carry out holiday test at 1.5kV to ensure no faults.
• Demobilise from site and removal of trade waste

Results:

Application costs for the aerobic reactor were kept to a minimum as the specified coating systems, RS 500P & RA 500 both feature moisture tolerant qualities during application. For this reason humidity and dew point are not a concern, negating the need for de-humidification. The coating system is easy to maintain with an expected life in excess of 15 years.