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Standard: Q/CNPC 38-200Z
Coating grade: strengthening level
Technical specification: minimum thickness of deep bottom is more than 300 m.
"Surface" is more than 500 m
The total depth is more than 80 m.
24h or 48h. cathode stripping: less than 6
Porosity at the bottom section: grade 1-4
Porosity of bottom bonding surface: grade 1-4
Adhesion of 24h or 48h: grade 1-2
0 degrees C or -30 C, resistance to 1.5 degree bending: no crack.
Anti 15J impact: pinhole free
50kg scratch resistance: scratch depth less than 500 m without leakage point.