5. Tolerance of Weight and dimensions.
Weight: As the table on this specification mentioned, the weight shall not vary by more than ±10%；notice: the weight tolerance also suitable to single pipe sizes over NPS4(DN100)
Diameter: For the pipe NPS 1 1/2(DN40) and under, outside diameter tolerance shall not vary more than ±1/64 in.(0.4mm), for pipe NPS 2(DN50) and over, the outside diameter shall not vary more than ±1%.
Thickness: The minimum wall thickness at any point shall not more than 12.5% under the nominal wall thickness specified.
6. End Finish
Unless otherwise specified, the pipe shall furnish as the following practice:
Unless specified on the purchase order, NPS 1 1/2(DN40) and smaller, end finish shall be at the option of the manufacturer.
The pipe size is NPS 2(DN50) and above, thickness less than 0.5 in.(12.7mm), shall with beveled ends, the thickness larger shall be plain ends.
Usually the beveled ends angle is 30°, +5°, -0°, and with a roof face of 1/16 in. +/-1/32 in. (1.6mm+/-0.8mm).
The threaded ends will be discussed with the client as the purchase order requirement.
7. Numbers of Tests
For continuous-welded pipe, the sizes NPS 1 1/2（DN40） and smaller, the lot shall contain no more than 25tons of pipe. For the size of NPS 2 and larger, it should no more than 50tons, For seamless pipe and electric-resistance-welded pipe, a lot shall contain no more than one heat, and at the option of the manufacturer shall contain no more than 500 lengths of pipe or 50 tons of pipe.
8. Galvanized Pipe
Galvanized pipe ordered under this specification shall be coated with zinc inside and outside by the hot dipped process. The zinc coating weight and test should according as the specification requirement.