Surface Finish and Oiling

Surface Finish
Classification Specification
Dull Finish 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 electro discharge texturing machine. The
dull finish is usefull in drawing because lubricant oil can be
evenly spread over the entire surface, thereby reducing the
possibility of friction. The fine grains also help to boost paint
adherence and extend the steel life span of the steel.
Dull Finish Ra (μm)
E3 E5 E7 E9
1.50~2.50 1.00~1.80 0.70~1.30 0.40~0.80
Oiling

It is recommended that customers use product promptly to avoid the possibilities of rusting during storage or shipment Customer can choose kind of oil and quantity. Oiling improves corrosion resistance but cannot be the perfect way to protect steel from rust. Also, non-oiled and DOS oiled products are easy to rusting so, POSCO Maharashtra strongly recommends to apply general oil and use the product as soon as possible.

Classification Quantity (Mg/m²) (Both Sides)
Heavy 3,000~4,500
General 1,800~3,000
Light 800~1,800
Thin 200~800
DOS - D 50~100
DOS - S 20~50
DOS - U 10~20