Surface Finishes
Dull finish, which is attained by attaching numerous fine grains onto the steel surface, is often called pear-skin finish or ‘egg-shell texture’.
The grains are made by steel grit blasted roll. The dull finish is useful in drawing because lubricant oil can be evenly spread over the entire surface, thereby reducing the possibility of friction. The fine grains also help boost paint adherence and extend the steel life span.
Dull finish Ra ( m) |
||
|---|---|---|
| D5 | D7 | D9 |
| 1.00~1.80 | 0.70~1.30 | 0.40~0.80 |
Oiling
It is recommended that customers use product promptly to avoid the possibility of rusting during storage or shipment. Customers can choose kind of oil and quantity. Oiling improves corrosion resistance but can not be perfect way to protect products from rust. Also, non-oiled and DOS oiled products are easy to rust ing so., POSCO strongly recommend to apply with general oil and use the products as soon as possible.
| Classification | CODE | Oiling weight (mg/m2 ), both sides standard |
|---|---|---|
| Normal, HEAVY | AH | 3,000~4,500 |
| Normal, GENERAL | AG | 1,800~3,000 |
| Normal, LIGHT | AL | 800~1,800 |
| DOS-A | BD | 80~140 |
| DOS-A | BS | 40~80 |
| DOS-A | BU | 10~25 |
