135M Finishing Mill Group

The finishing mill group is located in the high-speed wire-rod workshop. Rolling by 10 unit rack continuous micro-tension rolling mill , rolling the ∅17 ~ ∅21mm of rolled piece transported from upstream into ∅5.5 ~ ∅16mm finished wire rod. The mill guaranteed exit speed is 90m/s. (When the specification of finished product is ∅5.5mm)

Process parameters:

● Incoming specifications: 17～21mm

● Incoming material temperature: 850℃

● Finished product specifications: 5.5～14mm

● Rolled steel types: plain carbon steel, low alloy steel, high alloy steel, high-quality carbon structural steel

● Exit speed of the 10th aircraft: 90m/s.

Equipment performance

1．Technological parameter:

● Incoming material Specification： ∅17～21mm

● Incoming material temperature： >850℃

● Finished product specification： ∅5.5～14mm

● Rolled steel type：carbon steel, low alloy steel, high alloy steel, high-quality carbon steel, structural steel.

● Exit speed of the tenth rack：90m/s。

2．Equipment performance：

● Mill form：Cantilever roller ring rolling mill

● Rack quantity：10 stands(1~5 stands are ∅230 rolling mills,6~10 stands are ∅170 rolling mill)

● Arrangement form：Top cross 45°,10 stands combined drive

● Roller ring size：∅230 rolling mill：∅228.34~∅205×∅126×72mm; ∅170 rolling mill：∅170.66~∅153.5×∅95×62mm;

● Rolling force： ∅230rolling mill：152kN; ∅170rolling mill：107.8kN

● Rolling torque： ∅230rolling mill：2.86kNm; ∅170rolling mill：1.61kNm

● Driving motor： DC motor; Power：1600kW×3stand. or 5500 kWAc frequency conversion motor. Revolving speed：700~1200 r/min; Working revolving speed：900~1100r/min

● The unit lubrication way：Thin oil lubrication; System oil pressure：0.35～0.6MPa; Total consumption：1500L/min; Oils：Mobil 525; Cleanliness：10m

● Roll cooling water： water pressure： 0.6MPa; Consumption：Maximum 10´30m3/h

● Guard hydraulic system：Working pressure：20MPa; Systems flow：35 l/min

● Mounted roller working pressure：Max 25MPa

● Unload roller working pressure：Max 45MPa

● Attachment：Unload roller tool(∅230) 1set; Mounted roller tool(∅230) 1set; Unload roller tool(∅170) 1set; Mounted roller tool(∅170) 1set; Changing roller hydraulic pump 1set

● Unit composition ：∅230 rolling mill (5 stands), 170 rolling mill (5 stands),speed increasing box, large base, breakwater and capillary groove, buffer tank, protective cover,couplings, pipes of finishing train etc.

Structural characteristics of finishing mill：

Finishing mill totally contains 10 units,composed by 5 stands 230 rolling mill and 5 stands 170 rolling mill ,the 10 stands racks is arranged by 45 top cross type . Before 5 stands roller ring diameter is 228.34 ~ 205 × 72mm, after five stands roller ring diameter is 170.66 ~ 153.5 × 70mm, 10 stands racks driving intensively.

Finishing mill unit is combined by ten mills, speed increasing box, big support base, arc tooth coupling, baffle board, the protective cover and guides etc.

Main structural characteristics of finishing mill as following:

● Unit composed by 5 stands 230 rolling mill and 5 stands 170 rolling mill, the strength of the unit is more powerfully.

● The unit uses top cross 45 layout, reducing equipment center of gravity height, increasing the stability of the unit,reducing the weight of the equipment, operation and maintenance more convenient as well.

● Adjacent racks are arranged at 90 °to each other,achieving twist-free rolling.

● Roll box with plug-in structure, cantilevered roll ring, cabinets equipped with eccentric mechanism for adjusting the roll gap. Eccentric sleeve is equipped with an oil film bearing and roller shaft, fixing roller ring with taper sleeve at the cantilever roller shaft end;

● Bevel gearbox is composed of box, transmission shaft, spiral bevel gear pair. All gears are hardened grinding gear, axial modification,The accuracy level of spiral bevel gear is six, and cylindric spiral gear bevel is five to insure the smooth working of high speed.

● Roll box and bevel gearbox are connected by bolts, a part of roller box body plug into the bevel gearbox to let roller shaft gear and 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 exchanged.

● Roller shaft at the roll side oil film bearing was designed tapered structure, so that, at the racks with a strong load,roll shaft can still get a uniform load distribution from the oil film bearing when the roll shaft bending. Thereby the lifetime of the roll shaft is increased.

● The axial force of the roll shaft beared by a pair of thrust ball bearings , this ball bearing mounted on the no axial clearance resilient, because of the very small axial clearance of ball bearing itself, therefore,the roll shaft can accurately locate at the axial direction, which ensured the rolling precision of roll, meanwhile, ensured the dimensional accuracy of the rolled piece.

● Roll gap adjustment is by rotating screw rod which having left and right screw thread and nut, so that two eccentric relative rotation, the spacing between the roll shafts changes roll gap with the eccentric relative rolling line symmetry movement of eccentric sleeve, and maintain the existing rolling line and guides position unchanged.

● Collars are tungsten carbide,connected on the cantilever roll shaft by taper sleeve, we replace the collars by special hydraulic roll change tools, which are more convenient and easy.