Effect of Emulsion Lubrication Process on Surface Quality of Cold-rolled Uncoated-tin Steel Plate

The micro-morphologies of the cold-rolled uncoated tinplate surface was observed by means of three-dimensional profile microscope and scanning electronic microscope. Fricological properties of the two rolled lubricating oils were tested by a four-ball extreme pressure tester. The results show that the linear chromatism and scratches of cold-rolled uncoated tinplate base are related to the lubrication effect of cold roll gap area. The specifications used in working site are as follows: use rolling oil with high film strength, concentration（mass fraction） of（4.5 ±0.8）% for tank No.3, content of iron powder is not greater than 400×10^-6, the reduction rate of 4th mill is 30%-35%, the reduction rate of 5th mill is 27%-33%, the work roll surface roughness of the 5th mill is 0.4-0.6 μm. The linear chromatism and scratches on the uncoated tinplate have been reduced obviously by the use of the optimized lubrication process.