Large Diameter In-Tank Repair on Ropes

Overview

An in-situ repair was required to reinstate the integrity of a leaking sea-water ballast tank caisson. The application environment was hot with high relative humidity.

The repair site was 6 meters above base level of the tank, requiring the work to be carried out on ropes.

Scope

The line had the following specifications:

Structure Ballast Tank Caisson
Surface Preparation Sa 2.5
Class Approval ABS & Lloyds
Design Pressure 300 kPa
Design Temperature 900C
Application Temperature 300C
Design Life 10 years
Wrap Length 1.2 m
Pipe Diameter 1.1 m
Geometry Pipe, metal clamp, bolts, and seal nut
Corrosion Type Internal
Defect Details 100 mm circumferential slot

Solution

  • Confined space and rope access trained personnel were required
  • Temporary clamp used to seal live leak
  • Technowrap 2K™ HA system used to wrap the large diameter pipe and temporary steel clamps, which created complex geometries
  • Fatigue management system employed due to the hot and humid environment inside the ballast tank
  • Detailed QA/QC procedures captured repair details for future reference

Benefits

  • No hot works required
  • The Applicator's extensive experience ensured the wrap was applied to a high quality despite quick curing times due to the application temperature
  • A commitment to the Client's safety processes and ongoing communication ensured the job was completed safely with high productivity
  • Careful monitoring and documenting of QA procedures ensured a high quality wrap despite the high ambient temperature and relative humidity

IC Integrity

iasgroup is a partner in the IC Integrity JV, providing leading production critical cold work solutions that remove or minimise the need for shutdowns. The JV is home to market leading technologies such as TechnowrapTM and QuickflangeTM.