“Test procedures are to confirm the water-tightness of tanks and watertight boundaries, the structural adequacy of tanks and the weather-tightness of structures/shipboard outfitting.”
THERE’RE TWO TYPE OF TEST
1- Structure test
Structural Testing is a test to verify the structural adequacy of the construction of the tank (hydro static test)
Structural testing may be carried out after the vessel is launched, some shipyard, they can be done in dry-dock.
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2-Air leak test
Leak Testing is a test to verify the tightness of the boundary (air testing, compressed air fillet weld testing, vacuum box testing)
Tank air test may be carried during Block stage, Pre-erection stage or erection stage in dry-dock. Depending on yard work flow and schedule.
For speedup the process, The fillet air test can be carried out during block stage as below description:
As the require, “2Bar during the test”
Pressure is Stactic pressure of included the Dynamic pressure ???
Pressure in Hose or Hose nozzle ??? ( Pressure in nozzle is Dynamic pressure v^2/2g)
Nozzle ~ 12.5mm – Fixed diameter
Hose diameter ??? how much is required (HHI use Fie hose 65 mm in Diameter)
The Bigger Hose the lower Velocity of Water jet
There’s unavoidable some area can not be carried out Air test, as per the flexibility and agreement with Class site, MPI both side or PT can be done as alternatives (due to damaging equipment, inaccessible ect.,)