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4. OPERATION PROCEDURES
4.1 Pre Dive Checks tool visual check
Vortex Dredge - Mini Gas Sampling Tool - Version 2.2
10,000psi rated, ROV specific, main
isolation valve and orientation.
Main relief valve.
Vortex relief setting is
1800psi (124 bar)
It is not uncommon to see around 200 psi
drop in pressure after closing main
isolating valve during ascent to surface
whilst main relief valve ‘resets’