Nominal
Pipe
Size
(mm)
KCF Inner Surface Roughness Assurance Value
AP Grade BA/MP Grade EP Grade
Ry Ra Ry Ra Ry Ra
1/8" 25
m
2.5
m
100
inch
4.5
m
0.6
m
20
inch
1.0
m
0.2
m
7
inch
1/4"`2"
6A`40A
3.0
m
0.5
m
20
inch
0.5
m
0.12
m
5
inch
2-1/2"`4"
50A`100A
4.0
m
0.6
m
25
inch
5"`6"
125A`300A
0.7
m
0.15
m
6
inch
Measured range 12.5mm 4.0mm 4.0mm
Cutoff 2.5mm 0.8mm 0.8mm
EP is an abbreviation for Electropolishing BA (MP) for Bright Annealing (Mechanical Polishing), and AP for Acid.