1. The purpose of the equipment
The finishing mill group is composed of top crossed 45° High-speed wire-rod finishing mills.
The finishing mill group is located in high-speed wire-rod workshop. Through 10 unit rack the continuous micro-tension rolling mill will be transported upstream Æ 17 ~ Æ 21mm of rolling, rolling become Æ 5.5 ~ Æ 16mm finished wire. The working speed of 90m/s is insured. The specification of end product is Æ 5.5mm.
2. Parameters
As follow table:
3. Structural characteristics of the high speed wire rod rolling mill
Finishing mill unit is combined with ten mills, speed increasing box, support base, arc coupling, waterproof slot, waterproof plate, the protective cover, piping and guide of finishing mill. Mill frame is composed of three Æ 200mills and seven Æ 150 mills, frame use top crossed 45° Composition form to achieve no twisting, no contact axis, little axis and shock for equipment, besides, it decrease the center of gravity height, the stability increased as well, in the mean time, the total weigh has decrease and it is easy to maintain. Ten frames are concentrated transmission.
Roll frame is composed of roller box, bevel gearbox and spare parts of bevel gearbox.
Roller box and bevel gearbox adopt outside combinational instruction, decrease the size of bevel gearbox to decrease the weight of finishing mill, decrease the space of mills to make their structure compact. Roller box used cantilever roll loop, there is eccentric locking collar in the box to adjust roll gap. Film bearing and roll shaft are inside eccentric locking collar, taper sleeve is used to fix roll loop which is in the end of roll shaft.
Bevel gearbox is composed of box, transmission box, spiral bevel gear roll and synchronized gears. All gears are hardened grinding gear, geartooth correction is needed. The accuracy level of spiral bevel gearbox is six and round bevel gearbox is five to insure the smooth working of high speed.
Roller box and bevel gearbox are connected by bolts, a part of roller box plug into the bevel gearbox to let two synchronized gears in bevel gearbox meshed. Roller box and bevel gearbox are fixed by two locating pin, the roller box with same specification can be changed.
The axial force of the roll shaft beared by a pair of thrust ball bearings, this ball bearing mounted on the axial clearance in the absence of the resilient washer, because the very small axial clearance ball itself, therefore the roll shaft to accurately positioned in the axial direction, which ensures accurate roll rolling precision, which is to ensure the dimensional accuracy of the workpiece.
The roller shaft near the film bearing is designed in the form with taper, so the roller shaft can bear uniform load distribution even it is bend. So the lifetime of roller can be improved.
The adjustment of roll gap is to rotate feed screw with left and right thread and nut. When the two eccentric rotated relatively, the distance of two rollers changed with the symmetrical eccentric relative movement of eccentric locking collar, so the location of former roller line and guide can be maintain.
Roller loop is tungsten carbide, it is connected on the cantilever roll shaft, we use the specific hydraulic changing roll equipment to replace roll loop, it is convenient and easy.
Material specification | Æ17~21mm |
Material temperature | >900ºC |
Produce specification | Æ5.5~16mm |
The kinds of rolling steel | Carbon steel, low alloy steel, high alloy steel, high-quality carbon structural steel |
Speed of the exit of tenth frame | 75m/s |