METHOD OF PRODUCING COLD-ROLLED AUTOMOBILE SHEET Russian patent published in 2011 - IPC B21B1/28 B21B1/36 

FIELD: process engineering.

SUBSTANCE: invention aims at increasing quality of sheets intended for producing automotive face parts. Proposed method comprises cold rolling at reversing or continuous mills, strip coil annealing and temper rolling. Cold rolling of strips with thickness h-0.5…2.0 mm and width of 1.0…1.65 m at reversing mill is carried out at grain-oriented rolls with microrelief of the final stand: Ra=3.2…3.7 mcm and Pc=70…80 units/cm for first 70 km of strip length after roll changing. Note here that, at h=0.5…0.7 mm, specific rolling tension T_sp is taken to equal 55…46 N/mm², while at h=0.8…1.0 mm, T_sp =46…37 N/mm², and, at h=1.1…2.0 mm, T_sp =35…29 N/mm², while additional T_sp for h=0.5 mm is set to equal 70 N/mm², for h=0.6…0.8 mm T_sp = 60 N/mm², for rest h, T_sp = 50 N/mm². Cold rolling at continuous mill is carried out in grain-oriented rolls of final stand with microrelief: Ra=3.2…3.7 mcm and Pc=70...80 units/cm in first 1000 t after roll changing, tension T at downcoilers of this mill at h=0.5… 1.3 mm is 1.2…1.6 times higher with increase in h, while for h= 1.4…2.0 mm, T increases with increase in h equal to 1.2…1.8 times for all widths of the strip. Note here that, after annealing, wet temper rolling is carried out at oriented rolls with Ra=2.9…3.5 mcm and Pc = 70…90 units/cm with consumption of temper rolling fluid varying from 40% to 60%, at concentration of said fluid of 3-5% and temperature of 40…55°C.

EFFECT: production of required sheet micro geometry.

4 ex