Quality inspection standard of aluminium alloys extruded tubes for ships
1.Surface quality
the aluminium alloys extruded tubes surface does not allow cracks, corrosion exists.
the surface of the aluminium alloys extruded tubes from the skin, the bubble should be cleared, but the removal process should not make the aluminium alloys extruded tubes for ships diameter or wall thickness deviation beyond the allowable range.
marine grade aluminum alloys extruded tubes
Marine grade aluminium alloys extruded tubes surface of the bumps, scratches, scratches, pressure pit and other defects should not exceed the depth of aluminium alloys extruded tubes for ships diameter to allow negative deviation, and should not make marine grade aluminium alloys extruded tubes diameter or wall thickness deviation exceeds the allowable range.
Aluminum tubes surface straightening depth should not be greater than 0.5mm, and should not make aluminum tubes diameter or wall thickness deviation exceeds the allowable range.
Aluminum tubes surface allows the presence of oxidized color, not rough white and dark spots.
2.Low magnification organization
Aluminum tube on the low-volume tissue samples are not allowed to crack, shrink, stomata, bright grain exists, The depth of the layer on the low magnification of the aluminum tubes shall not exceed the allowable negative deviation of the pipe wall thickness and the wall thickness deviation of the aluminum tube shall not exceed the allowable range.
3.Mechanical properties
The mechanical properties of aluminum tubes include tensile strength, specified non-proportional elongation strength, elongation at break and so on.
In addition, the extruded aluminum profiles inspection also includes ultrasonic testing, etc., by the supply and demand sides to agree on the inspection site and inspection level, and in the drawings or contracts sp