Marine Gas Insulation AS has the only class approved refurbishment system for 0 - hour upgrade of SG (Spiral Generation) MOSS type LNG insulation
For an IMO type B Cargo tank in general, the main purpose of the insulation system is to:
The original SG (spiral generation) insulation is prone to a variety of defects originating from the application process, material behaviour and operating conditions such as frequency of loading / de-loading – but generally all failure modes can be traced back to the design of the system itself. Defects will typically show after time and can be observed as extended de-lamination of vapour barrier and spray shielding, extensive and frequent surface cracking as well as complete through thickness cracking.
The MGI Thermo upgrade system is class approved and designed according to the IGC code specifically for the SG insulation system but can in principle be used for any MOSS type LNG tank insulation. The upgrade can briefly be described as follows: All through-going cracks will be repaired by injecting Polyurethane foam in order to seal damaged original insulation. The original combined vapour barrier and sprayshield is removed and replaced by a reinforced layer of polyurethane foam and a specially developed cryogenic polymeric coating. This method will minimize gas leakage through the insulation, hence reduce nitrogen consumption and improve vapour ingress protection. Additionally the thermal performance will be improved as the added Polyurethane has a very low conductivity, and increased tightness will minimize mass transport through the insulation
The upgrade system can be applied for repair of damaged insulation as well as for improved thermal performance of otherwise sound existing systems. The method can be used on complete tanks or only upper hemisphere according to the owners needs and requests.
An upgraded SG insulation system will be improved with respect to operational stability, environmental impact, safety and thermal performance:
Depending on the size of the vessel and the quality of the original insulation, this could potentially reduce the need for expensive reliquefaction with 30 – 60 tons of LNG pr. day
Ill conditioned insulation will result in increased heat ingress with corresponding loss of cargo as well as higher maintenance and operational costs. A well maintained insulation system saves money as well as the environment. MGI Thermo can offer insulation repair and upgrade solutions for most any kind of self supporting tanks for liquefied gas, independent of cargo temperature.
MGI Thermo can offer tailor made insulation solutions for any kind of self supported tanks. When possible, our principle is to rectify damaged areas with polyurethane spray foam, ensuring best possible bonding to the cargo tank as well as to adjoining original insulation. For IMO type B tanks or A and C where the original insulation is not bonded to the tank surface it will be a case by case consideration if the repair insulation will be new panel inserts, spray foam or a combination of both. No repair job is the same so detail knowledge of each different system as well as practical experience is important for a satisfactory result.
MGI Thermo offer various solutions for pipe insulation repair in cooperation with our partners: