Size variance or dimensions exceeding the standard of tolerance. Where "size" mainly refers to the outside diameter and wall thickness of the pipe. Usually someone size variance used to call "tolerances in particular" that equate the term deviations and tolerances are less strict, should be called "deviations in particular." Error herein may be "positive" or "negative", and rarely appear in the same pipe, "positive and negative" deviation of line.
Note: calculate theoretical weight calculation formula of common profiles:
M-mass Kg; f-area m2/m; L-m in length; density ρ-*Kg/m3
☆ F cross section calculation method:
1, square F= A2
2, steel F=3.1416x$ (D-$) $-D-diameter thickness
3, width steel, flat steel F= AX$ a-