Nominal Grit 

Ra measurement

Typical applications and techniques

 Micron (micrometer)

Micro-inch 

 80

2.5 

100 

Dull polish - applicable for tube, bends and tees in general food processing subject to daily cleaning in place (CIP). Normal abrasive techniques achieve this.

 100

1.2

48

120

1.0

40

150

0.8

32

Satin polish - used by high end food and beverage plants, cosmetics, toiletries and with standard pharmaceutical and biotechnology applications. Easier to CIP. Sequential use of abrasives is required.

180 

0.6

24

240

0.5

20

320

0.4

16

Bright polish - top end pharmaceutical (water for injection), high value biotechnology materials, semi-conductors, solvents and pure gases. Abrasives plus electropolishing normally required.

500

0.1

4-8