哪位高手指导下下面是什么标准？

dayao605

FINISH:
NICKEL PLATE PER
1 Z- i5 a: e- C4 l- x+ s, ZQQN290 CLASS1 GRADE G

wjxwin2006

QQ-N-290是美国的电镀镍标准
CLASS和GRADE 的意义如下：
; O  |! j0 I3 m' o8 n/ v8 ^Class 1    Corrosion protective plating
" O1 G' ?: F" r/ t* r. d8 DClass 2    Engineering plating
9 q* g7 ]) Z1 c8 B5 ~4 `
Grades- Class 1 plating shall be of the following grades
- h* Y) x1 k3 ]% [8 PGrade A    0.0016 inch thick
% I% `6 W% t7 FGrade B    0.0012 inch thick
- @5 p) j* d5 d6 D* X+ hGrade C    0.0010 inch thick
Grade D    0.0008 inch thick
" Y' b3 q# v, u0 ~7 ~& @; EGrade E    0.0006 inch thick
Grade F    0.0004 inch thick
9 k9 v8 R2 G2 K- QGrade G    0.0002 inch thick