Category: Technowrap™ engineered composite repairs

Date: 2017

Client: Major North Sea Operator

Location: UK North Sea

Scope

The stair tower on large North Sea platform was out of use due to heavy corrosion on the structural members. The operator contracted ICR to deliver a cost effective option to re-instate the stairwell to its original design capacity. Phase 1 took place in July 2017 whereby work commenced on the lower section of the stair tower with approx. 80 metres of beams and tubulars being repaired. Phase 2 began in August 2017 to repair the upper section of the stairwell. 

Solution

Technowrap™ SRS – ICR’s structural carbon fibre repair system – was recommended to provide added toughness. A low temperature curing resin was used and designed to suit ambient conditions in the North Sea.

The client provided a surface profile of Sa2.5 (grit blasting). Complexity of the scope required maximum efficiency from the onboard fabric maintenance (FM) team and prior to mobilisation, ICR trained the FM crew on the application of gel coating. This was applied within 4 hours of blasting in order to hold the blast and prevent gingering. A team of four ICR technicians worked back to back within a double skin habitat to maintain a suitable environment. Materials were prepped and ready for the next shift to ensure optimum productivity on the job. 

Results & Benefits

• The stairwell composite repair is a long term integrity solution which will avoid corrosion in the future and is designed for the remaining life of the asset 
• Cost effective solution compared with stairwell replacement 
• A quicker solution delivered by multi-skilled technicians which ensured the stairwell was back in use as safely and timely as possible 

Date: 2015

Client: Major Global Operator

Location: UK North Sea

Scope

A 48” discharge caisson had a large number of through-wall defects over a vertical length of 23 metres that required immediate attention. The scope of the work was to provide an engineered design, with 20 years repair lifetime. This required live leak sealing the numerous through-wall defects and applying both Technowrap™ 2K and Technowrap™ SRS over the defect areas. 

Solution

The Technowrap™ 2K and Technowrap™ SRS repair using ICR’s Splashzone™ resin system was installed live. 

The combination of the two repair products was a requirement to withstand both the internal pressure plus the axial bending moment resulting from the wave loading. Having successfully overcome all challenges, ICR’s composite engineering team was able to successfully complete the repair of length 23 meters on the 48” caisson. All 40 plus through-wall defects were successfully sealed and the structural integrity of the caisson was reinstated for an extended lifetime of 20 years. 

Results & Benefits

• All 40 plus through-wall defects were successfully sealed and the structural integrity of the caisson was reinstated for an extended lifetime of 20 years 
• Applying the repair live resulted in zero impact on production and operations to the client and providing an extremely cost effective solution 

Date: December 2019

Client: Major Operator

Location: North Sea

Scope

Two large laydown areas onboard an operator’s asset offshore in the North Sea were suffering from external corrosion and multiple through wall defects resulting in water ingress. As the roof was classified as a laydown areas and subjected to personnel traffic there was a requirement that the load capacity of the roof was factored into the design. This unique design ensured that the laminate could withstand the applied loads and impacts associated of +5kN/m².

Solution

ICR provided an engineered design using four layers of Technowrap™ DRS. Combining the properties of the Technowrap™ SRS (Structural Rehabilitation System) carbon fibre and DRS a rubber toughened epoxy resin system. Our integrated approach, providing engineering, materials, technician training and installation, all in-house, has enabled ICR to become an industry specialist. Third party training for the contractor on application and QA/QC procedures was provided and the contractor was subsequently
supervised by a ICR technician.

Results & Benefits

• There were multiple areas with through wall defects and more were to be expected following mechanical surface cleaning preparations
• As a result it was decided that ICR would prefabricate composite plates to cover any through wall defects before the surface preparation commenced
• Following the successful installation of Technowrap™ DRS, the integrity of the roofs was restored for a 10-year defined lifetime

Date: July 2019

Client: Major Operator

Location: Central North Sea

Scope

The pipe deck on the client’s asset had suffered extensive corrosion resulting in severe wall loss and through wall defects. This was the third phase of a 22 bay pipe deck repair. 7 bays measuring 3m x 6m required a repair solution totalling 126m². Multiple through-wall defects and low wall readings were found. 

Solution

The bays were grit blasted to a SA2.5 surface profile. For any areas that were through-wall, 6 layers of our DRS Carbon Fibre solution was utilised. This consisted of a 2 layer composite plate – fully cured – bonded directly over the defects followed by a 4 layer wet lay up. For all non through-wall areas, 4 layers were applied. Fully engineered calculations produced by the ICR technical team. 

Results & Benefits

• The repairs were designed to seal all through wall defects as well as providing an engineered design lifetime of 20 years 
• The DRS resins provide a rubberised molecule resin which absorbs and dissipates impacts from thoroughfare and use as a landing area 
• An anti-slip coating was also applied over the completed pipe deck area. Long term corrosion protection 
• No hot work required 
• No heavy lifting or steel components 

Scope

ICR’s UK Onshore team was asked to complete a Technowrap™ composite repair scope at a nuclear power station site in England where replacement was not practicable due to severe access restrictions and isolation issues. 

Solution

Although typical composite resin systems within a confined space area require breathing apparatus, ICR was able to use its bespoke resin system and installed a Technowrap™ engineered composite repair to eliminate the requirement. Following visual inspection and risk assessment, the area was grit blasted with the pipework remaining in service at all stages. The repair was implemented and signed off within a 3-day window.

Results & Benefits

• No hot work required, reducing safety risk 
• Cost effective solution 
• 20 year design life achieved 
• Has led to several further scope enquiries from client 

Scope

On removal of insulation during plant shutdown, severe external corrosion under insulation was found on an approx. 3m length of 2” to 4” diameter water/ethanol pipework between valves and branches. ICR were approached to propose a solution to restore the integrity of the pipework and allow the plant to be rapidly returned to service. The repair design conditions being 2.5barg pressure, ambient/-35°C temperature with 2 year design life.

Solution

A Technowrap™ 2K LT engineered composite repair solution was proposed with surface preparation by hand to minimise chance of pipework going through wall. ICR mobilised technicians and material to site. During the repair, additional pipe sections were found to be corroded and repair scope doubled. ICR provided additional materials and technicians with night shift established to enable repairs to be completed to the required schedule. From initial approach to the repairs (including additional scope) being completed and signed off, was just over a week.

Results & Benefits

• Pipework integrity restored 
• No through wall penetration during repair 
• ICR technicians worked day and night to complete the repair with increased scope allowing the plant to return to service in line with schedule 

Scope

EDF Carbon Steel 20” Condensate Pipework Repair Water Line (TG2- 20” Condensate Return). The line was suffering from a through wall defect caused by external corrosion.

Solution

ICR were requested to provide an engineered repair solution to restore the integrity of the line for a design life of 5 years. This repair is subsequently designed for a through-wall defect.

Results & Benefits

• Engineering design calculation complete with design sketch, materials and manpower to complete the 15-layer repair using the Technowrap™ 2K cloth with the Technowrap™ LT resin. 
• No hot work required 
• Defined life repair of 5 years 

Scope

EDF Emergent requested out of hours on Bank Holiday Monday 18” Carbon Steel Gen TX 2 Spare Oil Conservator which was suffering from a through-wall defect due to external corrosion of the weld. This repair was subsequently designed for a through-wall defect. 

Solution

ICR were onsite the following day, with an engineered repair solution of 8 layers of Technowrap™ 2K LT was delivered to restore the integrity for a design life of 15-years. 

Results & Benefits

• Technicians onsite within 24 hours, installation was delivered, QA/QC checked and handed back to site in a 3 day window 
• 15 year Design life 

Scope

ICR were engaged to provide a engineered composite repair solution on a produced water caisson prior to installation offshore. The previous caisson was corroded due to wave action causing thermal cycling. 

Solution

Two new sections of a 12” caisson were fabricated and sprayed with an internal coating prior to ICR applying the composite solution. It was a design requirement that surface preparation to Sa2.5 and was achieved prior to the application of 4 layers of Technowrap™ 2K using HT (High Teemperature) resin. 

These were then welded together and an angular profile of 45μ was achieved using bristle blasters. A composite wrap was then applied to cover the welded section. Heat blankets were used througout the process to assist curing. 

The change in temperature was taken into consideration by derating the allowable strains in line with ISO 24817.

Results & Benefits

• ICR technicians worked day and night for a total of 7 days to complete the repair 
• A repair lifetime of 20 years was given 
• The solution will prevent future corrosion due to thermal cycling, maintaining the integrity of the structure

Scope

Various repairs carried out on a Carbon Steel Demin Water Reserve Feed Tank. The tank was suffering from through-wall defects due to external corrosion. 

Solution

ICR were requested to provide an engineered repair solution to restore the integrity of the tank for a design life of 20 years.

Results & Benefits

• ICR provided engineering design calculation complete with design sketch, materials and manpower to complete the 8-layer repair using Technowrap™ 2K HA 
• 5 x Dayshifts, 5 x repairs 
• Fast & cost effective versus replacement